FI59084B - FOERFARANDE OCH ANORDNING FOER FRAMSTAELLNING AV MATTOR AV FIBER AV THERMOPLASTIC MATERIAL SAOSOM GLAS - Google Patents

Description

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France-France (FR) 750UO39 (71) Saint-Gobain Industries, 62, Bd Victor-Hugo, F-92209 Neuilly Sur Seine,

Ran ska-Frankrike (FR) (72) Marcel Levecque, Saint-Gratien, Jean A. Battigelli, Rantigny,

Ran ska-Frankrike (FR) (7 * 0 Berggren Oy Ab (5 * 0 Method and apparatus for making mattresses from thermoplastic material such as glass fibers - Förfarande och anordning för framställning av mattor av fibrer av thermoplastiskt material, sasom glas

The invention relates to a method for converting materials, such as glass, which can be thermally softened into fibers, by providing a gas stream and a gas jet, called a carrier jet, the jet direction of which is such that it encounters a gas stream and kinetic energy large enough to penetrate , so that an interaction zone is thus formed in the vicinity of the gas stream penetration path of the gas jet, and the thermally softened substance is fed to the interface of the gas stream where the gas jet penetrates, so that the substance enters the interaction zone where the substance then turns into fibers. Such a method is the subject of French Patent Publication No. 73 11525, entitled "Method and apparatus for producing fibers from thermoplastics".

It is an object of the present invention to provide a method which. According to the present invention, the fibers thus obtained can be made into layers, i.e. mattresses, in which the distribution and orientation of the fibers can be controlled and the excellent advantageous technical effects described below can be achieved.

* 2 59084

The invention therefore relates to a method of making a mattress of fibers made of thermoplastic material, in particular fiberglass, in which the thermoplastic material is stretched when introduced in a stretchable state into a zone where a secondary gas jet is penetrated into a main gas stream with less kinetic energy per unit volume and the fibers formed in the defibering zone are collected on a torn receiving surface, and the method of the invention is characterized in that the gases flowing from the defibering zone are divided, after passing through the fiber receiving surface, into at least two parts recycled to different positions in the chamber surrounding the receiving surface. to the defibering zone, and the other portion is recycled in the vicinity of the fiber receiving surface.

According to the invention, a second part of the gases is recycled back into the receiving chamber so that the gases flow practically parallel to the receiving surface of the fibers.

According to one feature of the invention, the portion of the gases recycled to the defibering zone is contacted with the main stream in a direction substantially parallel to the mainstream flow, and the other portion of the gases is recycled to the position between the defibering zone and the fiber receiving surface.

When spraying a liquid resin binder onto the fibers, the process of the invention is to partially purify the gases before they are recycled back to the receiving chamber to remove at least a portion of the resin components of the binder.

According to another feature of the invention, the amounts of gas recirculated in the vicinity of and above the receiving surface of the fibers are controlled to control the direction and distribution of the fibers on the felt.

The invention also relates to an apparatus for carrying out a method according to the invention, which apparatus comprises a main gas flow generator and at least one secondary gas jet discharge nozzle, the jet forming an angle with the main gas, a thermoplastic feed source provided with feed openings, each opening being connected to the jet discharge a plurality of defibering centers, a conveyor for receiving fibers having a suction chamber downstream, and a device according to the invention characterized in that the conveyor forms one of the substantially closed receiving chambers in which the defibering takes place and the outlet of the recirculation tube is connected to the suction chamber through two recirculation channels, with the first channel entering the level of the fiberization zone and the second channel opening in the vicinity of the fiber receiving conveyor.

The features of the invention are explained in more detail below in connection with the accompanying drawing, which more or less schematically shows the apparatus according to the invention.

The various figures in the drawing can be briefly explained as follows:

Figure 1 is a schematic representation of a combination of all members of a plant connected to a device for defibering molten glass by feeding glass to the main gas stream and gas jet interaction zone and a device for assembling fibers into a mattress, and various devices for eliminating contamination.

Figures 2-12 are schematic views of a plant analogous to the plant of Figure 1, but with some additional structures and their connections; in these figures: 4,59084

Fig. 2 is a perspective diagram of the main members of both the defibering device and the decontamination device according to the second embodiment of the invention; Figure 3 is a plan view of the apparatus of Figure 2 the direction of arrow C direction in Figure 2; Figure 4 is an elevational view of the device according to the reach of Figure 4, seen in the direction of arrow D in Figure 2, but certain elements of the omitted for simplicity; Figure 5 is an elevational view as seen from the direction of arrow E direction of Figure 2, but certain elements of the omitted and some other means out of the hacked to expose the other, they cover bodies; Fig. 6 is an enlarged schematic view of an apparatus associated with one of the defibering stations seen in the same direction as Fig. 5, some means for simplifying the drawing schematically shown; Figs. 7 and 8 are flow diagrams showing the operation of the control devices used to promote uniformity of fiber distribution in the emerging fiber mattress; and Figures 9 and 10 are further diagrams of fiber distribution modes that may be obtained by adjusting certain devices schematically shown in Figures 11 and 12.

Referring first to Figure 1, and with reference to this figure, it should be noted that the defibering device and fiber receiving device shown in this figure may be different and that the invention is directed to arrangements other than those shown in Figures 2-12.

It should also be noted in connection with the following description of Figure 1 that some of the elements of the defibering device shown therein are similar to, or analogous to, the corresponding elements described in the aforementioned French Patent 73,115,255 (see Figures 15A, 15B, 15C and 15D of this publication). the organs can be found in French Patent Publication No. 73 36169, which is also referenced above.

The defibering apparatus of Figure 1 comprises main gas stream generators 154, 156 and 158 and secondary gas jet or carrier jet generators 148, 150 and 152. Each such pair of generators, as described in French Patent 73 11525, provides an interaction zone 142 in which molten glass 146 is fed in a crucible. through the existing holes. The molten glass can be fed to 59084 crucibles, e.g. up to the branches 136, 138 and 140 of the front tank.

As described in French Patent 73 11525, a plurality of carrier jets are preferably connected to each main stream; then a plurality of glass wires, each associated with a single carrier jet, are fed to each main stream, with the result that a group of defibering centers is obtained in connection with each of the main stream generators 154, 156 and 158. In addition, as described in said patent publication, in the transverse direction of the device there are several main current-generated and carrier-gas-generated jets and glass wire supply holes. Thus, as shown in Figure 1, each main current generator, e.g., generator 154, is only one developer in a set of peripherals in which the generators are in extension with each other. All of the defibering centers formed by the developer groups feed the stretched fibers into a hollow guide 168, 170, or 172. These guides act as channels for directing fibers from the various defibering center groups in an inclined direction from the defibering zone and feeding them to the perforated fiber receiving conveyor 180.

As will be appreciated, the gases from the main gas generators and the carrier jet generators of each group flow with the fibers to the upper or inlet ends of the channels formed in the hollow guides 168, 170 and 172, and each of these fiber and gas streams is indicated in Figure 1 by reference numeral 12.

As shown in Figure 1, the defibering device is located some distance from the fiber receiving conveyor 180 in a receiving chamber 100 formed of a plurality of wall elements, which is preferably substantially closed. The fiber receiving conveyor forms at least a large part of one wall of the receiving chamber, and the function of this conveyor is to transport the obtained fiber mattress to the left of the chamber under this left wall. As will be appreciated, the walls have appropriate openings for the supply of fuel and air needed by the main gas stream and the carrier jet generators. In addition, there are openings suitable as passage openings for the melt glass pre-furnace branches and crucibles for feeding the molten glass to the defibering device.

For collecting the fibers, suction chambers 16 are arranged below the fiber receiving zone of the conveyor for the perforated fiber receiving conveyor, which are open upwards and provided with a line 7 6 59084 for connecting them to each of its own vortex separators 18. Each vortex separator has a flow line 19 connected to , which presses the sucked gases into a conduit 34 which forms a recirculation line connected to one end of the fiber receiving chamber 100. The guide partitions 132, which are arranged in the area of the line where this is connected to the chamber 100, uniformly distribute the recycle gases to the fiber receiving chamber.

To cool the fibers as they exit the guides 168, 170, and 172, water atomizers 50 are preferably located both above and below the fiber and gas streams 12 from the hollow guides. Second spray nozzles 13 are arranged downstream of the water sprayers; from these nozzles a binder liquid, which is a resin substance, preferably an adhesive, is sprayed onto the fibers, which hardens or solidifies when the formed mattress is subsequently heated, for example in an oven through which the mattress passes to the left in Fig. 1.

Due to the spraying of water and liquid resin glue on the fibers, the gases leaving the suction chambers 16 carry with them considerable amounts of moisture and resin components. These components, as well as those small fiber chips that may pass through the receiving conveyor when carried by the gases during suction, must be removed from the gases before the gases are recycled back into the fiber receiving chamber.

This removal takes place in the embodiment shown by vortex separators 18. The separation is promoted and assisted by the washing effect of the water sprayers 45 arranged inside the suction chambers 16.

The general flow pattern of the gases in the recirculation system of Figure 1 is indicated by arrows 29. The flow of gas in the fiber receiving chamber is not only provided by the suction fans 19, but is further enhanced by the effect of the main gas flow and carrier jets in the fiberization centers. Because the upper ends of the guide tubes 168, 170, and 172 are open toward the zones of the defibering centers, circulating gases enter from the upper ends of the guide tubes and the remainder are associated with the fiber and gas streams 12 after the guide tube outlet ends.

The liquid and other similarly entrained components separated by the vortex separators 18 are removed from the bottom of the separators through the outlets 25 and collected in the outlet 103. In this way, the various liquid and solid components accumulated in or entrained in the gas stream can be removed and separated. so that they do not have to enter the fiber receiving chamber with the recycled gases. To further eliminate contamination, these separated liquids are specifically treated as described below, but it should be noted at the outset that although virtually all of the gas exiting the receiving chamber through the fiber receiving conveyor is recycled back to the fiber receiving chamber, some of these gases exit the receiving chamber 35 down to the action of the vacuum cleaner 44. This part of recycled gases. represents an order of magnitude of 5 * 10% of the total volume flowing through the perforated fiber receiving conveyor and corresponds approximately to the amount of additional gas at which the main gas stream and carrier jet continuously supply generators are located in the defibering centers. The gases escaped by the vacuum cleaner 44 are led to an incinerator 39, where the temperature preferably rises above 600 ° C, after which the treated gases can be removed to the atmosphere without adversely contaminating it. 90-95% of the gases passing through the fiber mattress in the formation zone are recycled and do not pollute the atmosphere.

In addition to the recirculation of gases in the arrangement according to Figure 1, the water coming from the vortex separators 18 can also be treated and recycled. For this purpose, the pump 104 presses water from the collecting well 103 into the tank 52; a flicker or other screen, schematically marked at 51, is interposed to retain solid particles before water enters the tank. Water is circulated from the tank 52 by a pump 53 through a heat exchanger 105 to cool the water, and the cooled water is returned to the tank 52. The heat exchanger 105 is cooled by a heat transfer medium which is circulated by a pump 107 through a cooling system 106. The structural details of these bodies may vary and will not be explained or shown herein as they do not form part of the invention.

Water from the tank 52 is also pumped by a pump 55, preferably equipped with appropriate control devices (not shown), to water spray nozzles 50 and 45. Pump 55 may also send water to fiber binder manufacturing station 108, which may be of any suitable construction and from which binder is fed to spray nozzles 13. .

In addition, a portion of the water is preferably fed to station 109 for treatment to remove binder components dissolved therein. This removal is preferably carried out in the manner described in detail in French Patent No. 7,288,683, according to which the water is exposed to high pressures and high temperatures and then cooled. This treatment results in the resin components becoming insoluble, after which they can be easily removed, for example by centrifugation. The purified water is then passed to tank 52 for reuse. The solid components removed by the station 109 and also by the screen 51 connected to the tank 52 are transferred by suitable conveyors 112 and 57 to the waste treatment station 113, which, as described in French Patent 73 36169, may consist of a heater or burner raising the solid waste temperature by 600-700 ° C to burn the resin binder components contained in the waste and to sinter any fibers present. If desired, the latter can be returned to the fiber cycle, i. among the ingredients from which molten glass is made for defibering.

Make-up water can be introduced into the system up to the supply pipe 111, which opens into the tank 52.

Many of the structural and functional features described above in connection with Figure 1 are also included in the embodiment shown in Figures 2-12, but in addition some parts of the device are adapted in different ways and other preferred features are included in the embodiment shown in said figures.

In this regard, reference is made to Figure 6, which is a schematic representation of a number of defibering units or centers included in the apparatus more generally shown in Figures 2, 3 and 5 and 5. As mentioned above, Figure 6 also schematically shows the number of defibering centers in the area. details of different devices on a much larger scale than other patterns in this group of patterns. The molten glass can be fed to the center shown in Fig. 6 in generally the same way as described above in connection with Fig. 1, i. downstream of the pre-furnace branch 136, which communicates with the crucible 1 ^ 2, from which the molten glass filaments can be fed to the defibering zones created by the combined action of the carrier jets generated by the developer 1 ^ 8 and the main current generated by the main stream generator 15 ^. The gas and fiber stream 12 leaving the defibering center enters the upper end of the guide tube 168, i.e. the inlet end, which directs the stream to the downstream fiber receiving conveyor 180 (see Figures 2, 3 and 5) · 9 59084

As shown in Fig. 1, in addition to the application form of the French patch 73 11526, part of this firefighting is shown in Figs. 15A, 15B, 110, the defibering centers are located on the receiving conveyor. and in addition, the defibering units or centers are distributed along the length of the receiving conveyor, as schematically shown in Fig. 3, which shows five pre-furnace branches 136-140, and five associated hollow guides 168-172.

In Fig. 3, the repetition of the defibering stations in the transverse direction of the receiving conveyor 180 is schematically indicated by the letters a-f.

Figure 3 also schematically shows in broken lines the pre-furnace branches 136-1 * 10 with which each fiberization station group a-f is fed. These pre-furnace branches can be fed from the pre-furnace shown in FH.

As can be seen, each defibering station a-f includes a plurality of defibering centers, i. a plurality of carrier jets in a position relative to the individual strands of molten glass as described in detail in French Patent 73 11525 ·

In the embodiment shown in Figures 2-12 and especially in Figures 2-4, several parts corresponding to the parts according to Figure 1 are denoted by the same reference numerals. However, it will be seen that Figures 2-12 schematically show a different arrangement and arrangement of a number of utilized structural members and devices. Here are some important differences.

As shown in the perspective view of Fig. 2 and Figs. 5 and 6, the fiber receiving chamber 100 is located above the fiber receiving conveyor 180 and the fiber receiving chamber is provided with upward extensions 100a at each guide 168-172, with defibering devices positioned at the top of each extension. Parts of two of these upwardly extending extensions are generally shown in Figure 6, which shows that the neighboring extensions 100a are so far apart that they leave room for the worker to access some adjustable devices, which have not yet been explained.

As shown in Figs. 1-6, the suction chambers 16 are located under the fiber receiving belt of the conveyor 180, and these chambers are connected by wires 17,590 to the vortex separators 18. The suction fans 19 cause the gases from the suction chambers 16 to pass through the vortex separators 18 and, after the liquid suspended therein has been separated, feed them to the gas recirculation duct 34. In the embodiment shown in Figures 2-6, the recycle gas stream is divided and directed to different points in the system. Thus, the duct branches 34a and 34b branch laterally from the main duct 34, and as best seen in Figures 2 and 3, the left-hand extension of the duct 34 in the figures comprises a U-shaped portion 34c that feeds a portion of the recycle gas directly into the chamber 100 at the upstream end.

As best seen in Figure 6, the gases flowing in the branch duct 34a are fed through openings in the vicinity of the upper end, i.e. the inlet end, of the proximal guide, which in this figure has the number 168. At its upper end, the guide 168 is shaped to prevent vortices in the flow, and gases from said source penetrate the upper end of the guide in part by suction, which tends to result from the combined action of main gas streams and carrier jets and the guide 168. Figure 6 shows only one main current generator 154 and only one carrier jet generator 148, but it is clear that these devices are arranged in groups as schematically shown in a-f in Figures 2 and 3.

Referring further to Figure 6, it can be seen that some of the gases circulating along the branch duct 34b are also fed from openings in the vicinity of the upper end, i.e. the inlet end, of the guide 168, which are also profiled to reduce the turbulence of the flow. In addition, this wall of the guide has an adjustable movable part, i.e. a flap 168a, which pivots on the hinge 168b and is provided with an adjustable screw system 16c including a handwheel located in the space between the adjacent extensions 100a of the receiving chamber so that the worker can adjust the position of this wall part. This independently adjustable wall portion is preferably in extension with each of the fiberization stations a-f, so that the distribution of the fibers can thus be adjusted, as will be explained more fully below. The apparatus may have one or more inspection hatches ad to allow the worker to more easily monitor the operating conditions of the defibering and to service the equipment parts of the defibering stations.

11 59084

Referring further to Figure 6, both branch passages 34a and 34b are provided with additional openings for conducting a portion of the gases from either side of the guide 168 to spaces inside the upwardly extending extension 100a of the guide 168.

It is also preferred to fit a flexible portion 16d to the lower end of at least one wall of the guide 168, the shape of which can be changed by adjusting screws 16e to allow the worker to adjust the position and shape of the flexible wall portion and thus perform further fiber distribution adjustment as described below.

In industrial activities, it is necessary to manufacture products in which the weight of the fibers per unit area, i.e. distribution is uniform. This result is usually not achieved by nature, but to achieve this, suitable devices must be available to direct the fibers to specific points in the mattress formation zone. Namely, the irregularities in the distribution of the fibers can be either local or affect the whole mattress.

Consider now Figures 7 and 8, each showing a plan view of a guide 168 having an upper or inlet end shown at the top of the figures and a fiber outlet end at the bottom. These figures show devices for correcting local irregularities in the distribution, namely swivel flaps 168a. Each of them is articulated and independently adjustable as described above in connection with Figure 6. These flaps 188a can be turned more or less into the medium stream 29 provided by the fiber and stretching gas stream 12. When one of these passages, e.g. 29 there are return flows. These return currents bend the flight path of the fibers locally inward on the downstream side of the flap. In this way, as shown in Fig. 8, a regrouping of fibers on the downstream side of the flap is achieved, which tends to harmonize the fiber distribution in the mattress.

12 59084

Figures 9 and 10, in which the guides 168 are shown in plan view, show an irregularity in the overall distribution of fibers with too high a fiber density at the left edge compared to the right edge when viewed in Figure 9.

Figures 11 and 12 show an apparatus for correcting such an irregularity in the fiber distribution. By modifying the cross-sectional shape of the exit point of the medium guide 168 by changing the shape of the flexible wall l68d with the adjusting screws l68e so that, as shown in Fig. 12, the cross-sectional area of the guide 168 is larger on the right than on the left, the amount of medium in Figure 10, is magnified. By appropriately arranging the screws 168e, the fiber distribution is made uniform in the fiber stream exiting the guide 168.

It is clear from the above that the devices according to the invention effectively eliminate the environmental pollution which occurs in factories which manufacture fiberglass mattresses, in particular in factories which use the fiber manufacturing technique described in French patent publication 73 11525 ·

The method of recycling back the utensils inside and around the defibering device is utilized in an advantageous manner, in particular by dividing the recyclable gas stream into parts which are recycled at different points in the system, thus improving the regularity of fiber distribution in the fiber mattress during its manufacture. Inconsistencies in fiber distribution can be corrected by means of adjustable devices that are easily accessible to the worker during the manufacture of the fibers.

The possibility of dividing the recyclable gas stream into parts which are returned to different points in the system offers another considerable advantage, namely that the structure of the fibrous mattress, i.e. the orientation of the fibers in the finished product can be modified.

In fact, referring to Figures 5 and 6, a portion of the recirculated gas stream 29 is brought into contact with the stream 12 in the region of the upper end of the guide 168, in a zone close to the defibering device 142-148-154, and follows the stream 12 to the receiving member 180. The other part of this current is brought into contact with the current 12 13 59084 in a zone located near the lower end of the controller 168 and follows this current up to the receiving member 180. The resulting flow of the mixture of stream 12 and gases 29 returned to the system as described above follows a groove directed from the defibering device to the receiving conveyor and forms a large angle with the receiving member 180. This angle is generally between 60 and 90 °, so that this flow can be considered substantially vertical.

A third of the recycle gases is directed down the duct 34c extension 34c directly to the end of the chamber 100 upstream of the series of defibering stations, to a zone immediately adjacent to the receiving conveyor 180 above it, and in a direction substantially the same as the direction of this conveyor.

The flap set 101 can be used to adjust the amount of recycle gases 29 entering the passage 34c and thus adjust the intensity of the flow along the conveyor 180 with respect to the flow that descends and forms a large angle with the conveyor as described above.

When the flow rate in the direction of the conveyor is high compared to the intensity of the descending flow, there is a strong tendency for the fibers or fiber pieces to settle in layers parallel to the conveyor 180, giving the fiber mattress and final product better heat dissipation and flexibility

When the intensity of the descending, i.e. substantially vertical, flow is high compared to the intensity of the horizontal flow, there is a strong tendency for the fibers to descend to the conveyor as a very messy structure, thus giving the fiber mattress and the final product better flattening resistance. This makes it possible to give the finished product the most suitable properties for its intended use.

The device also includes safety members and are shown in Figure 2.

These members comprise a chimney 34f, which may be separated or connected to the duct 34 by a set of flaps 34d. Door 34a allows the plant to be connected to the atmosphere, if necessary, especially during plant start-up.

Claims (13)

14 59084 A method for producing a mattress made of fibers of thermoplastic material, in particular fiberglass, in which the thermoplastic material is stretched when introduced in a stretchable state into a zone where a secondary gas jet is introduced into a main gas stream having less kinetic energy per unit volume than jet -fibers formed in the zone are collected on a torn receiving surface, characterized in that the gases flowing from the fiberization zone are divided, after passing through the receiving surface of the fibers, into at least two parts which are recycled to different positions in the chamber surrounding the receiving surface. , and the other part is recycled in the vicinity of the fiber receiving surface. A method according to claim 1, characterized in that the second part of the gases is recycled back to the receiving chamber so that the gases flow substantially parallel to the receiving surface of the fibers. Method according to Claim 1 or 2, characterized in that the part of the gases recycled to the defibering zone is brought into contact with the main stream in a direction which is substantially parallel to the main stream flow. Method according to one of Claims 1 to 3, characterized in that the second part of the gases is recycled to the position between the defibering zone and the fiber receiving surface. A method according to any one of the preceding claims, wherein the liquid resin binder is sprayed onto the fibers, characterized in that the gases are partially purified before being recycled back to the receiving chamber to remove at least some of the binder resin components. Method according to one of the preceding claims, characterized in that the amounts of gas recirculated in the vicinity of and above the receiving surface of the fibers are regulated in order to adjust the direction and distribution of the fibers on the mattress. 59084 15 Apparatus for carrying out a method according to any one of claims 1 to 6, comprising a main gas flow generator and at least one secondary gas jet discharge nozzle, the jet forming an angle with the main gas, a thermoplastic material supply source provided with supply openings, each opening being connected to the jet discharge nozzle a fiberizing center, and a conveyor for receiving fibers with a suction chamber downstream, characterized in that the conveyor (180) forms one of the walls of the substantially closed receiving chamber (100) in which the defibering takes place and that the outlet of the recirculation tube (17, 3 * 0 is connected to the suction chamber (16) and the tube opens at the inlet end to the receiving chamber (100) through at least two recirculation passages (34a, 34c_), with the first passage (34a) entering the level of the fiberization zone and the second passage (3 ^) opening in the vicinity of the fiber receiving conveyor (180). Apparatus according to claim 7, comprising binder and water spray nozzles (13, 50) located in the receiving chamber, characterized in that the separator (18) is arranged on the recirculation pipe, downstream of the suction chamber, in which the spray nozzles (45) are distributed for recirculating gases . Apparatus according to claim 7 or 8, comprising a fiber guide member located between the defibering centers and the conveyor, characterized in that the first channel (34a) terminates substantially at the height of the top of the fiber guide member (168). Device according to one of Claims 7 to 9, characterized in that the second channel (34c0), which is connected to the receiving chamber near the conveyor, terminates at the upstream end of the receiving chamber (100). Device according to one of Claims 7 to 10, characterized in that the additional recirculation channel (34b) terminates in a receiving chamber between the upper part of the fiber guide device (168) and the conveyor (180). 16 59084 Device according to one of Claims 7 to 11, characterized in that the at least one adjustable valve (101) is connected to at least one recirculation channel (23a, 3b, 3c) for controlling the amount of gases distributed and recirculated to these different channels. Device according to one of Claims 7 to 12, characterized in that the fiber guide element (168) is provided with an adjustable wall (168a, 168b, 1668d) for adjusting the gas inlet and the distribution of the fibers to the conveyor (180).