US3645063A

US3645063A - Machine for assembling an insecticidal device

Info

Publication number: US3645063A
Application number: US62546A
Authority: US
Inventors: Jacques Foirest
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 1969-09-16
Filing date: 1970-08-10
Publication date: 1972-02-29
Anticipated expiration: 1989-02-28
Also published as: DE2045594C3; DE2045594A1; DE7034287U; GB1293663A; FR2060219B1; GB1293662A; DE2045594B2; FR2060219A1; BE750818A

Abstract

Machine for impregnating absorbent sheets and inserting them in receptacles comprises a conveyor passing said sheets through an oven to dry them, a rotating table carrying a plurality of presses for receiving and impregnating the dried sheets, and an assembly line comprising a conveyor belt, means for placing a receptacle half on the belt, followed by an impregnated sheet and a second receptacle half, and means for squeezing the resulting stack to produce a complete receptacle enclosing an impregnated sheet.

Description

United States Patent Foirest 1 Feb. 29, 1972 MACHINE FOR ASSEMBLING AN INSECTICIDAL DEVICE Inventor: Jacques Fcirest, Monfermeil, France L'Oreal, Paris, France Aug. 10, 1970 Assignee:

Filed:

Appl. No.:

Foreign Application Priority Data Sept. 16, 1969 France ..693 1461 11.8. C1 ..53/53, 53/111, 53/127 Int. Cl. ...B65b 57/02, B6Sb 63/08 Field of Search ..53/53, 111, 127

llllllll llllllllll [56] References Cited UNITED STATES PATENTS 2,232,783 2/1941 Hausheer ..53/1 11 R X 2,913,862 11/1959 Sabee Primary Examiner-Travis S. McGehee Attorney-Holcombe, Wetherill & Brisebois [57] ABSTRACT Machine for impregnating absorbent sheets and inserting them in receptacles comprises a conveyor passing said sheets through an oven to dry them, a rotating table carrying a plurality of presses for receiving and impregnating the dried sheets, and an assembly line comprising a conveyor belt, means for placing a receptacle half on the belt, followed by an impregnated sheet and a second receptacle half, and means for squeezing the resulting stack to produce a complete receptacle enclosing an impregnated sheet.

17 Claims, 4 Drawing Figures e 2e TN 38 42 4 3 4 Patented Feb. 29, 1972 3 Sheets-Sheet 1 Patented Feb. 29, 1972 5 Sheets-Sheet 2 Patented Feb. 29, 1972 3 Sheets-Sheet 5 MACHINE FOR ASSEMBLING AN INSECTICIDAL DEVICE SUMMARY OF THE INVENTION Certain insecticidal products tend to evaporate while emitting toxic vapors, and the size of the zone of toxicity is a function of the size of the surface over which the insecticidal product is in contact with the atmosphere. In order to improve the efficacy of such liquid insecticides, it has been suggested that small sheets of absorbent material be impregnated therewith and a particular insecticidal sheet has been proposed which consists of an absorbent support impregnated with a mixture of an active compound such as 'dimethyldichlorovinyl phosphate and a liquid chlorinated terpene having a very high viscosity. In order to permit efficacious evaporation of the active insecticidal compounds carried by such absorbent materials, it has been suggested that a receptacle for the insecticidal sheet or the like he provided which is made in two parts which are partially hollow. This receptacle also comprises in combination male and female members located on each of the two parts so as to position them relatively to each other by reciprocal interfitting, and hook members which permit the two parts to be snapped together.

It is the object of the present invention to provide an automatic machine for continuously impregnating sheets of absorbent material and introducing them into receptacles which said sheets are adapted to fit. It should be emphasized that the absorbent sheets must be introduced into their receptacles quite rapidly because of the large commercial market for this product and the small cost for putting together the assembly consisting of the receptacle and its insecticidal sheet which is commercially acceptable. Moreover it is advantageous to provide an automatic machine for this type of assembly work because of the relative toxicity of the chemical products impregnating the sheets of absorbent material, to which product the laborers would be continuously exposed if the process could not be carried out without manual intervention.

It is accordingly an object of the present invention to provide as a new article of manufacture a machine adapted to impregnate sheets of absorbent material with, for example, an insecticide. This machine comprises, means for feeding the sheet of absorbent material, which means consists of an endless carrier which traverses a tunnel oven at a temperature high enough to insure that the plates of absorbent material are dried without being damaged. The machine also comprises a device for impregnating the sheets of absorbent material introduced by the aforesaid feeding means. This impregnating device consists of a rotating table carrying at least one press, between the two plates of which the absorbent material is introduced. The two plates of the press are adapted to grip the sheet between them and distribute thereover the chemical product with which they are tobe impregnated. Finally, the device comprises an assembly line consisting of an endless belt made of supports placed side by side and connected to each other, said supports first receiving from a first distributor one of the components of the receptacle in which the sheet is to be placed, and then receiving from transfer means the impregnated sheets issuing from the impregnating device, and finally receiving from a second distributor the second com ponent of said receptacle, which is attached to the first by means of a press positioned in alignment with the assembly line.

In a preferred embodiment of the invention the feeding means comprises an endless chain traveling over a pair of drums, one at each end of the path of travel. This chain carries supports perpendicular to its path of travel. The feeding chain moves step by step and it advances at each step through a distance equal to the distance between two adjacent supports on the chain. The tunnel oven through which the feed chain passes is at a temperature between 110 and 150, and preferably about 130. It takes from 3 to 5 minutes for an article to pass through the furnace, depending upon the temperature selected. Transfer means is positioned between the feed means and the impregnating means and comprises two parallel moving belts on each of which one of the edges of the sheets leaving the furnace rest. The supports on the chain pass between the two belts, which are driven in a direction which brings the sheets toward the impregnating device. The impregnating device comprises several impregnating presses regularly spaced about the rotating table. This table is intermittently rotated to produce an angular displacement equal to the angular distance between two adjacent presses. They are driven at the same frequency as the feed chain. The rotating table of the impregnating device carries the lower stationary plates of the impregnating presses and the upper plates of said presses are actuated by movement of a lever in a direction perpendicular to the plane of the rotating table. This movement is caused by contact with a stationary circular cam. The upper and lower plates of each impregnating press comprise surface sheets of sintered metal or porcelain, one face of which comes in contact with the sheet of absorbent material while the other face defines an injection cavity supplied through a metering pump. The injection cavities are fed at a pressure between 2 and 3 kgJcmF, with equal quantities being injected through the upper plate and the lower plate of the press. The cavities are supplied only when the press is closed, with the two sintered metal sheets of each press gripping the sheet of absorbent material. Each of the lower and upper plates of an impregnating press is connected to a metering pump which injects into the injection cavity of the corresponding plate half the quantity of the product with which each sheet is to be impregnated. The metering pumps are valved pumps actuated by the passage of a movable member over a stationary cam. These pumps are all carried by the rotating table of the impregnating device. The metering pumps are supplied from a reservoir having a constant level, which is substantially equal to that of the valves of said pumps. The impregnating device comprises eight presses, five of which are simultaneously in closed position. The sheets are supplied and ejected at positions situated at from each other, and the edges of the sheets project outside the plates of the impregnating presses. The sheets are ejected from the presses by an ejector acting on the edges of the sheet outside the plates of the press, which ejector is actuated by an eccentric synchronized with the rotation of the rotating table. Transfer means at the output of the impregnating device comprises a stationary grill and a movable grill actuated for translational movement by two connecting rods. The bars of the movable grill pass between the bars of the fixed grill. The transfer means also comprises drive rollers which turn about their axis, and over which the impregnated sheets travel. The transfer means is positioned between the impregnating device and the conveyor belt and leads the impregnated sheets to a centering device which positions the sheets with respect to the support "at the right of said sheets which support already carries the lower part of the receptacle for the sheet. Each support on the conveyor belt carries a positioning pin. The conveyor belt comprises, between the second distributor and the press which fastens the two parts of the receptacle together, control means for relatively positioning the components of the receptacle and the sheet with respect to each other.

The press is followed by a hydraulic cylinder which laterally feeds tabs which may be attached to one side of the assembly of the receptacle, after closing thereof by pressing the two elements thereof against each other. These tabs are adapted to maintain the equilibrium of the receptacle in a desired position at its moment of use. The combination of the movements of the feeding chain, the rotating table, the impregnating device, the movable grill and the transfer means at the output of the impregnating device, and the conveyor belt are synchronized by a single programmer, for example a cam-type programmer.

In order that the invention may be better understood, a preferred embodiment thereof will now be described, purely by way of illustration and example, with reference to the accompanying drawings on which:

I 1v- 1v of FIG. 1.

In the example which will now be described a sheet about 12.5 cm. square will be impregnated. This sheet consists of cardboard made from a cotton and asbestos base. Each sheet is about 3.5 mm. thick and is impregnated with a mixture having insecticidal properties which evaporates slowly. This mixture consists of 10 to 40 percent dimethyldichlorovinyl phosphate and 90 to 60 percent of chlorinated terpene, such as is sold under the trademark STROBANE. Each sheet is impregnated with 30 grams of this mixture.

The receptacle in which the sheet impregnated in this manner must be inserted comprises two identical members adapted to be snap-fastened together, with each of said members forming one half of the receptacle and consisting essentially of parallel strips forming a grating. Said receptacle comprises a lateral tab adapted to hold it in position when it is placed in use. This tab is made of a plastic such as polypropylene.

Referring now to the drawings, it will be seen that reference numeral 1 indicated the feeding means for the machine as a whole, while reference numeral 2 indicates the impregnating device and 3 indicates the conveyor belt on which the sheet is positioned between the two components of the receptacle which is to contain it.

The feeding means 1 comprises an endless chain 4 turning at its two ends over two drums 5 and 6. The chain 4 carries supports 7 which project perpendicularly to its path of travel and are spaced from each other by a distance of several centimeters. The drum 5 drives the chain 4 in an intermittent step-by-step manner. At each step the chain advances by a distance equal to the distance between two successive supports. At the right of the drum 6 is a distributor 8 where the sheets 9 which are to receive the insecticidal product are stacked. The distributor 8 may be replaced by a hand feed. Between the drums 5 and 6 is an oven 10 through which the upper lap of the endless chain 4 passes, that is to say the part of this chain on which the sheets 9 are positioned between the supports 7.

The temperature of the oven 10 is 130 C. Its length is so calculated, with reference to the speed of movement of chain 4, that the sheets 9 remain about 4 minutes inside the furnace. When they reach the end of the chain 4 near the drum 5 the sheets 9 have been dried as a consequence of their passage through the oven 10. This drying is necessary to avoid hydrolysis of the product impregnating the sheet by the water initially contained in the absorbent material constituting the sheet. The sheets 9 which have been dried in this manner are placed on transfer means consisting of two parallel belts, l1a-l 1b, which belts travel around three

pulleys

12, 13 and 14. The portion of the belts between the pulleys l2 and 13 is horizontal. The pulley 14 drives the two belts 11a and 11b in the direction indicated by the arrow in FIGS. 1 and 2. The supports 7 pass between the edges of the belts and travel toward the impregnating device 2. Above the belts 11a and 11b is a roller 120 which is rotatably driven in order to assist in driving the sheets 9. In certain cases extracting means controlled by a pneumatic jack may be used to push the sheets 9 in the direction in which the belts 11a and 11b of the transfer means are moving.

The impregnating device 2 comprises a rotating horizontal table 15, the axis of rotation 16 of this table being vertical. The table carries eight identical presses 17 distributed about its periphery. Each press 17 consists of a lower plate 17a which is stationary and supported by the table 15 and a movable upper plate 17b actuated by a set of

levers

18, 19, 20, with the lower part of lever 20 engaging a circular cam 21 through a roller 22. The table 15 may be rotated intermittently in angular steps of 45. When the table is in rest position, one of the presses 17 is located in axial alignment with the transfer means consisting of the belts 11a and 11b. The movement of the table 15 is synchronized with the movement of the chain 4 so that a sheet 9 is placed on the belts 11a and 11b when the table 15 is at rest, and the table is rotated through an angle of 45 only after the sheet 9 mounted on the belts 11a and 11b has been engaged between the

plates

17a and 17b of the press 17 in axial alignment with the transfer means.

The profile of the cam 21 is such that the press 17 in axial alignment with transfer means Ila-11b is open while the press 17 at 45 to this position in the direction of rotation of the table shown on FIG. 1, is closed. The presses 17 between the said 45 position and the 225 position from the position of the press in alignment with the transfer means Ila-11b (said angles being taken in the direction of rotation of the table 15) are all closed. The three other positions of the press 17 are all, on the contrary, open. The

plates

17a and 17b of presses 17 are provided with a support, which is substantially square when seen in plan, and inside which is a central injection cavity of small volume, which cavity is closed by a sintered steel sheet. The sintered steel sheets carried by the two

plates

17a and 17b are face to face. The injection cavities of the two plates are supplied through flexible tubing 23a-23b connected to the plates 17al7b respectively. These flexible tubes 23a-23b are each connected to a metering pump 26. The pumps 26 are supported by the rotating table 15 and are valve pumps, controlled by a movable member associated with each pump and in contact with the stationary cam. The metering pumps 26 are supplied from a constant level reservoir 27. This level lies substantially in the same horizontal plane as the valves of the pumps 26. The pumps 26 are supplied only when the presses corresponding to the pumps are in closed position. The reservoir 27 contains the insecticidal product with which the sheets 9 are to be impregnated. This product is injected through the tubes 23a-23b in back of the sintered metal sheets under a pressure of 2.8 kg./cm. The

plates

17a and 17b are closed and grip between them a sheet 9. It should be noted that the dimensions of the sheets 9 are slightly greater than the dimensions of the

plates

17a, 17b so that the edges of these plates are not gripped between the plates of the press and only the central part of the sheet is impregnated.

The product contained in the reservoir 27 passes through the sintered metal surface and is absorbed by the sheet 9. During one revolution of the table 15 through 45 25 to 30 g. of the product is injected each 1.5 seconds in each sheet 9. When the sheet 9 inside a press 17a has gone through three-quarters of a revolution of the rotating table, the press 17 is again opened by the cam 21. At this moment, an arm 28 positioned on the part of the plate 17a furtherest from the center of the rotating table 15 is struck by a lever 29 at the bottom of the table 15. The lever 29 is actuated by an eccentric 30 and a spring 31. The arm 28 actuated by the lever 29 moves in guides formed in the table 15 parallel to the radius on which the center of the press with which said support 28 is associated lies. It is obvious that the drive means 29, 30, 31 are stationary and situated in alignment with the position which the press 17 occupies after having passed through three-quarters of a revolution from the position which this press occupied when it received a sheet 9 from the transfer means formed by the belts 1 la and 11!).

Transfer means 32 is positioned perpendicularly to the axis of the transfer means formed by the belts 11a and 11b. The transfer means 32 comprises a stationary grill 33, the bars of which are perpendicular to the axis of the transfer means 32 and a movable grill 34 actuated for translational movement by two

shafts

35 and 36 through two connecting

rods

35a and 36a. The grill 34 remains constantly horizontal in the course of this movement. The bars of the grill 34 pass between the bars of the fixed grill 33. At the end of this pair of

grills

33 and 34, on the side remote from the impregnating means 2, is an assembly of rollers 37 rotated by a motor 37a. The grill 33 is IIHA'I: mum

attached to electrical weighing means which makes it possible to verify, when the impregnated sheets 9 are positioned thereon, that the impregnation of said sheets is in fact sufficient.

At the output of this transfer means 32, that is to say on the side remote from the impregnating device 2, is centering means 38, which receives the impregnated plates from the transfer means 32, positions them, and places them in alignment with the assembly line 3. The assembly line 3 comprises a conveyor belt 3a carrying substantially square supports 39. At the four corners of each support 39 are positioning pins 40. The square defined by the four pins 40 of a support 39 corresponds exactly to the dimensions of a receptacle which is to receive the sheet 9. The assembly line comprising the conveyor belt 3a and its supports 39 travels from a vertical distributor 41 on which the lower parts 42 of the receptacle in which the impregnated sheets 9 are to be inserted are stacked. The conveyor belt then passes under the centering device 38. This device consists of two U-shaped supports 43, one of the arms of the supports being attached to the piston 44 of a pnuematic cylinder 45, while the other arms of the supports are formed by rollers 46 driven by a motor and a set of belts and pulleys. The supports 43 are pivotally mounted to turn about an axis 47 positioned at the point at which the center parts of the supports 43 are connected to the arms of those supports which are connected to the piston 44. When a sheet 9 is brought to the centering position 38 by the transfer means 32, this sheet rests on the rollers 46 which drive it up against an abutment and thus insure its accurate positioning. At this moment the hydraulic cylinder separates the rollers 46 by turning the supports 43 about this axis 47. The sheet 9 falls vertically in a well defined position and is located exactly in the central part of the lower member 42 of thereceptacle adapted to receive it. it is obvious that the conveyor belt 3a is driven intermittently step by step, with each step equal to the distance which separates two successive supports 39. The chain is stopped with one support 39 in alignment with the distributor 41 and another support 39 in alignment with the centering means 38.

A support 39 carrying a lower member of thereceptacle 42 and the impregnated sheet 9 is then led in two successive steps to a position beneath a distributor 48 supplying the upper members 49 of the receptacle in question. This distributor causes a member 49 to be positioned on the stack formed by the member 42 and the sheet 9. Beyond the distributor 48 in the direction of advancement of the conveyor belt 3 is a control device comprising a photoelectric cell 50 which makes it possible to verify the proper relative positioning of the

members

42, 9 and 49. These three components, after two steps by the conveyor belt 3, come into alignment with a press 51 which snaps the

members

49, 42 together. The press 51 is actuated by a pneumatic cylinder 52. Beyond the press 51 along the path of travel of the conveyor belt is a device 53 which attaches a tab 54 to the side of the receptacle which has been assembled by the press 51. This attaching step is effectuated by means of a hydraulic cylinder. The receptacle is then dropped from the end of the conveyor belt 3 through a passage 55 leading in the direction of the wrapping machine. The machine according to the invention may also be provided with a selecting and ejecting device at the end of the conveyor belt 3 for ejecting the receptacles. Such a device may also, of course, be positioned upstream of the passage 55. It should be noted that the movements of the supply chain, the rotating table, and the conveyor belt are synchronized by a cam type programmer.

The machine which has just been described operates as follows:

The sheets of absorbent material 9 mounted on the distributor 8 are located between two supports 7 on the chain 4 and stay inside the oven 10 for 4 minutes.

The chain 4 moves step by step, with each step equal to the distance between two successive supports 7. At the output of the oven 10 the sheet 9 is dried. It is then positioned by the chain 4 on the belts 11a and 11b which are driven by the pulley 14. The sheet 9, after being thus positioned, is inserted between the

plates

17a and 17b of the press 17, which is in axial alignment with the transfer means formed by the belts Ila-11. The table 15 is driven in rotation in angular steps of 45. At the beginning of the first step, the two

plates

17a and 17b of the press 17 close on the sheet 9, the edges of which extend beyond these plates. The injection cavities behind the sintered metal surfaces of each of the

plates

17a and 17b are fed at a pressure of 2.8 kg./cm. through the tubings 25, the rotating distributor 24, and the

passages

23a and 23b, with an insecticidal product contained in the reservoir 27. This supply is maintained until the press 17 is about to open, and is discontinued a little before the sheet 9 has traveled three-fourths of a revolution around the rotating table 15. When the sheet 9 has completed three-fourths of a revolution, the press 17 is opened, and the arm 28 pushes the sheet 9 in the direction of the transfer means 32, as a consequence of the action of the lever 29 on the arm 28. Sheet 9 is thus moved onto the bars of the fixed grill 33. The movable grill 34 advances the impregnated sheet 9 in several steps along the axis of the transfer means 32. The sheet thus reaches the rotating rollers 37 and passes from them into the centering device 38.

A support 39 on the conveyor belt 3, after having been loaded with the lower component of the receptacle 42 by the distributor 41, reaches a position beneath the centering device 38. Centering is effectuated by the rollers 46 which are power driven and force the sheet 9 against the stop. The piston 44 of cylinder 45 then acts on the supports 43 to separate the rollers 46. The impregnated sheet 9 falls inside the lower member of the receptacle.

In the course of the step-by-step advancement of the conveyor belt 3, the assembly comprising the member 42 and the sheet 9 comes into alignment with the second distributor 48, which adds to this assembly the upper member 49 of the receptacle, and then into alignment with the press 51 which snaps the two

members

42 and 49 together. The device 53 then attaches the tab 54. The insecticide dispenser thus completed is removed in the direction of the wrapping machine through the passage 55.

it will, of course, be appreciated that the embodiment which has just been described has been given purely by way of illustration and example and may be modified as to detail without thereby departing from the basis principles of the invention. ln particular, the parts of the machine in which the impregnated sheets are found, as -well as the impregnating device, may be placed inside a ventilated casing to prevent any toxic contamination due to the impregnating product.

, What is claimed is:

1. Machine for impregnating sheets of absorbent material with a liquid and for inserting each sheet in a receptacle consisting of two parts adapted to be snap-fastened together, with each of said parts forming one side of the receptacle, said machine comprising a device for feeding in the sheets of absorbent material, which feeding device comprises an endless conveyor which passes through an oven maintained at a temperature sufficient to dry the sheets of absorbent material without causing deterioration thereof, a device for impregnating the sheets of absorbent material supplied by the said feeding device, which impregnating device comprises a rotating table carrying at least one press having a pair of plates between which successive sheets of absorbent material are introduced, the two plates of the press being adapted to grip said sheets between them and to distribute therethrough the liquid product with which the sheet is to be impregnated, and an assembly line chain comprising conveyor means provided with longitudinally spaced supports adapted to receive a receptacle part, a first distributor positioned to place a first receptacle part on each support as it passes by, transfer means downstream of said first distributor positioned to transfer an impregnated sheet from said table to a position on a support above said first receptacle part and a second distributor downstream of said transfer means positioned to deposit a second part of said receptacle on each support above said Insane Anna sheet and first part, and a press positioned downstream of said second distributor to press the two parts of said receptacle together.

2. Machine as claimed in claim 1 in which the feeding device is formed of an endless carrier travelling over two spaced drums, said belt being equipped with supports perpendicular to its path of travel.

3. Machine as claimed in claim 2 in which the feeding means is actuated step by step, with the length of a step being equal to the distance between two adjacent supports on the chain.

4. Machine as claimed in claim 1 in which the oven through which the feeding conveyor passes is set for a temperature between 110 and 150 C., said feed conveyor operates at a speed such that a sheet thereon takes 3 to 5 minutes to pass through the furnace, depending upon the temperature of the furnace.

5. Machine as claimed in claim 1 comprising transfer means between the feeding device and the impregnating means, which transfer means comprises two parallel movable belts spaced to carry the edges of sheets leaving the oven so that the supports of said endless conveyor pass between the two belts.

6. Machine as claimed in claim 1 in which the impregnating device comprises a plurality of impregnating presses regularly spaced about the rotating table, and means for driving said table in rotation step by step through an angle equal to the angular distance between two adjacent presses, at the same frequency that the feeding device is operated.

7. Machine as claimed in claim 1 in which the rotating table of the impregnating device carries the lower stationary plates of the impregnating presses and the upper plates of these presses are actuated by lever means for movement in a direction perpendicular to the rotating table, said lever means being actuated by contact with a stationary cam.

8. Machine as claimed in claim 1 in which the upper plate and lower plate of each impregnating press comprise sheets of sintered metal or porcelain, one face of which comes in contact with the sheets of absorbent material, whereas the other face defines one side of an injection cavity supplied by a metering pump, each plate of the press being connected to an individual metering pump supplied from a constant level reser- 9. Machine as claimed in claim 8 in which the injection cavities are supplied with impregnating fluid under a pressure of between 2 and 3 kg./cm. with equal quantities injected into the upper and lower plates of the press, said injection taking place only when the two plates grip a sheet of absorbent material therebetween.

10. Machine as claimed in claim 6 in which the impregnating device comprises eight presses, five of which are simultaneously in closed position, and sheets are supplied from said feeding device and removed over said transfer means at positions spaced 270 from each other.

11. Machine as claimed in claim 7 comprising means for ejecting said sheets from the presses including an arm positioned to engage an edge of a sheet which projects outside the plates of the press, said arm being actuated by eccentric means which rotates with the rotating table.

12. Machine as claimed in claim 1 in which said transfer means comprises a stationary grill and a movable grill actuated for translational movement, the bars of the movable grill passing between the bars of the stationary grill, and the stationary grill being attached to electrical balancing means.

13. Machine as claimed in claim 12 in which the transfer means between the impregnating device and the conveyor means in said assembly line comprises drive rollers which are positively driven and on which the impregnated sheets travel.

14. Machine as claimed in claim 12 in which the transfer means between the impregnating device and the conveyor means in the assembly line leads the impregnated sheets to a centering device which positions the sheets with respect to a conveyor support in alignment with said sheet on which one part of said receptacle is already positi oned.

15. Machine as claimed in claim 14 in which each support in the assembly line carries positioning pins.

16. Machine as claimed in claim 1 in which the assembly line comprises between the second distributor and the press for assembling the two components of the receptacle, control means for positioning the components of the receptacle and the sheet with respect to each other and ejection means for ejecting defective assemblies.

17. Machine as claimed in claim 1 in which the press in the assembly line comprises lateral feeding means for bringing in tabs adapted to be fastened to the assembled receptacle after closing thereof said tabs being adapted to maintain the position of the receptacle when in use.

Claims

1. Machine for impregnating sheets of absorbent material with a liquid and for inserting each sheet in a receptacle consisting of two parts adapted to be snap-fastened together, with each of said parts forming one side of the receptacle, said machine comprising a device for feeding in the sheets of absorbent material, which feeding device comprises an endless conveyor which passes through an oven maintained at a temperature sufficient to dry the sheets of absorbent material without causing deterioration thereof, a device for impregnating the sheets of absorbent material supplied by the said feeding device, which impregnating device comprises a rotating table carrying at least one press having a pair of plates between which successive sheets of absorbent material are introduced, the two plates of the press being adapted to grip said sheets between them and to distribute therethrough the liquid product with which the sheet is to be impregnated, and an assembly line chain comprising conveyor means provided with longitudinally spaced supports adapted to receive a receptacle part, a first distributor positioned to place a first receptacle part on each support as it passes by, transfer means downstream of said first distributor positioned to transfer an impregnated sheet from said table to a position on a support above said first receptacle part and a second distributor downstream of said transfer means positioned to deposit a second part of said receptacle on each support above said sheet and first part, and a press positioned downstream of said second distributor to press the two parts of said receptacle together.

4. Machine as claimed in claim 1 in which the oven through which the feeding conveyor passes is set for a temperature between 110* and 150* C., said feed conveyor operates at a speed such that a sheet thereon takes 3 to 5 minutes to pass through the furnace, Depending upon the temperature of the furnace.

8. Machine as claimed in claim 1 in which the upper plate and lower plate of each impregnating press comprise sheets of sintered metal or porcelain, one face of which comes in contact with the sheets of absorbent material, whereas the other face defines one side of an injection cavity supplied by a metering pump, each plate of the press being connected to an individual metering pump supplied from a constant level reservoir.

9. Machine as claimed in claim 8 in which the injection cavities are supplied with impregnating fluid under a pressure of between 2 and 3 kg./cm.2, with equal quantities injected into the upper and lower plates of the press, said injection taking place only when the two plates grip a sheet of absorbent material therebetween.

10. Machine as claimed in claim 6 in which the impregnating device comprises eight presses, five of which are simultaneously in closed position, and sheets are supplied from said feeding device and removed over said transfer means at positions spaced 270* from each other.

14. Machine as claimed in claim 12 in which the transfer means between the impregnating device and the conveyor means in the assembly line leads the impregnated sheets to a centering device which positions the sheets with respect to a conveyor support in alignment with said sheet on which one part of said receptacle is already positioned.