US2058461A - Nozzle for machines for preparing soles for cement shoes - Google Patents

Description

Oct. 27, 1936. J. w. JOHNSON 2,055,461

NOZZLE FOR MACHINES FOR PREPARING SOLES FOR CEMENT SHOES Original Filed Oct. 3, 1933 2 Sheets-Sheet 1 wk .u

.......V. e 1 "EH? Z M? a Oct. 27, 1936. J. w. JOHNSON NOZZLE FOR MACHINES FOR PREPARING SOLES FOR CEMENT SHOES Original Filed Oct. 3, 1953 2 Sheets-Sheet 2 3nneutor Patented Oct. 27, 1936 UNITED STATES PATENT. OFFICE NOZZLE FOR MACHINES FOR PREPARING SOLES FOB CEMENT SHOES Original application October 3, 1933, Serial No.

ber 31, 1934, Serial ,No. 759,915.

Divided and this application Decem- In Great Britain October 10, 1932 1 Claim.

This invention relates to machines for preparing soles for incorporation in shoes. The invention is herein illustratively described in connection with the application of a solvent to acti- 5 vate a dry coating of cement upon a sole which is to be permanently attached to a shoe by means of cement and as embodied in a nozzle for a machine for applying a fluid, such as solvent, progressively to the margin of a piece 01 work, al-

though in various respects the invention is not so limited.

In the manufacture of compo shoes in which theoutsole is secured to the shoe bottom by cement, a common practice is to apply a coating 5 of'cement containing pyroxylin or other cellulose derivative to the flesh surface or attaching face 01' 'an outsole. Frequently this is applied in the form 01 a marginal stripe which may not extend fully to the edge of the sole and this coating is usually allowed to dry as the soles are accumulated prior to the time when they are needed for incorporation in shoes. Usually, the shoe bottom is also provided with a stripe of cement which is allowed to dry. Just before the outsole is to be applied tothe shoe bottom, the cement coatind on the outsole is activated by applying thereto a solvent for the cement, whereupon the shoe and outsole are brought into close contact in a press, such, for example, as that described in Letters Patent of the United States No. 2,047,185,

granted July 14, 1936, on the application of Milton H. Ballard, et al., until the cement has dried sufllciently to secure the outsole properly in place on the shoe.-

It has been a common practice hitherto. to apply a liquid solvent to the cement coating on the sole and to put it on manually by means of a brush. This practice is, however, disadvantageous from many points of view since, for example, 40 the application may be uneven and the cement may be displaced by the dragging action of the brush, and the solvent, unless great care is taken, may spread over the mid-portion of the sole where it is not needed or get on the edge and tread surface of the sole with a consequent danger of staining. More recently there has been used with great satisfaction an activator in the form of a highly viscous solvent. One form of such a softener is described in United States Letters Patent No. 1,959,321, granted May 15, 1934 upon an application filed in the name of Walter H. Wedger, wherein there are set forth certain desirable results which accrue from the use or such a solvent, such as the ability to apply the solvent in a predetermined position from which it is not readily displaced, the greater ease with which the sole thus coated may be handled and the reduction in the length of time during which the shoe must remain in the press. A lessened danger of squeeze-out, when pressure is applied, is another important advantage.

Quite clearly, too much solvent means a waste of material as well as an increase in the time required for the volatile constituents of the solvent to evaporate and, hence, an increase in the time during which the shoe must be kept in the press. On the other hand, too little solvent may readily result in starved joints and, hence, imperfect adhesion of the sole to the shoe. A moth-,- od providing for the application of a predetermined amount of viscous solvent in a plurality of separated threads is not claimed hereinsince it forms the subject matter of an application for Letters Patent of the United States Serial No. 692,043, filed October 3, 1933, in my name, for improvements in Method of preparing soles for cement shoes, of which this application is a division.

As illustratively described, the threads of viscous solvent are applied in ridges of sutllcient height to enable the solvent to be spread laterally under pressure. It is possible, however, by controlling the dimensions of these ridges to make the spreading extend over Just the required distance, thus eliminating squeeze-out. Solvent thus applied attacks immediately the cement directly beneath the threads, and as the liquid component of the solvent is absorbed in the cement the threads tend to stiffen or to form a thin surface skin. After the sole has been positioned upon the shoe and pressure has been applied, the ridges of solvent are spread laterally and, being capable of control as to their cross-sectional dimensions, can spread only so far as is desired to make them effective in activating the whole surface of the stripe -oi cement with a minimum of wetness in the joint. This makes it possible to absorb the wetness in a short time dwell and to keep the spread of solvent toward the edge iully under control so as thereby to eliminate squeeze-out.

If the dry cement is to be thoroughly activated, the solvent must be applied theretoin exactly the desired overlying relation. The determined position will vary slightly'in accordance with the wishes of the particular manufacturer but usually he will wish to keep the margin clean between the cement and the edge of the sole. This can be very readily accomplished when the solvent is applied in ridges or threads.

Inasmuch as the time interval between the oppllcation of solvent and the bringing together of a sole and shoe depends upon the particular operator, it is important that there shall be as little loss as possible of the volatile constituents of the solvent during this time interval. Another advantage of the application of solvent in a plurality of separated threads or ridges lies in the fact that the escape of the volatile constituents is less for any Pa t cular mass of solvent per running inch of margin to be activated when applied in separated threads than it is when applied in a ribbon or band. The reason for this is twofold: first, the area of contact between the threads of solvent and the band of cement is less than the area between a ribbon of solvent and the cement and, therefore, there is less opportunity for the escape of the volatile or active constituents of the solvent into the cement, and, second, the surface area of the threads of solvent is less, for that predetermined mass per unit length of margin which is needed to activate the cement, when it is applied in threads than when it is applied in a broad ribbon. Therefore, the opportunity for surface evaporation is less.

To get a perfect bond between the sole and the shoe by means of cement it is necessary that the whole band of cement shall be activated. On the other hand, if too much solvent is applied there is immediate danger of squeeze-out and there has been deposited upon the shoe an excess of solvent which must be volatilized and dried out before the shoe may be released from the press. The minimizing of the time dwell during which the shoe remains in the press is dependent upon the promptness with which the solvent is dried or absorbed and solvent fumes driven out of the cement joint. It will be understood that, if a given production is to be obtained, any increase in this time dwell causes an increase in the number of presses required. On the other hand, a reduction in time dwell means that the same machinery will produce more shoes in a given period. It is not always necessary that the joint shall have become completely dry at the time when the shoe is removed from the press but it must have at least attained that condition in which there shall be no subsequent separation of the sole from the shoe and, if the arrangement is such that the extreme edge of the sole is held adhesively when the shoe is removed from the press, then the margin will dry out safely as the interior portion of the Joint proceeds to harden.

Many difliculties are attendant upon the application of solvent by machine in such a way that a small quantity which is just enough but not too much will be deposited upon the cement uniformly. The continued application of a uniform quantity of material containing a cellulose derivative, such as pyroxylln, with its quick drying properties, depends not only upon the provision of a work feeding mechanism by means of which the pieces, such as unattached soles, are moved progressively at a suhst'antially constant speed but also upon the use of an applying device in which the exposure of the material to the air at the delivery opening does not affect the uniformity of application. By using a machine of the extrusion type in which the substance is forced under pressure through a nozzle, the diflleulty of applying a uniform quantity is minimized as compared with a machine employing a rotary brush or roll for the application of the coating material. It is found, however, that such material cannot be extruded with precision and witha,oss,4s1

out interruption of operation through the usual nozzle having a slit-like opening. The pressure cannot be'very large without extruding more than the desired quantity and, ifthe pressure is small and the opening narrow, it is almost impossible to keep the whole of the nozzle opening clear for any length of time. The clogging of even a small part of a slit, which happens frequently, leaves a bare portion and prevents the application of a uniform band. Furthermore, the diillculties of manufacturing a nozzle with such a slit-like opening of the desired restricted size, with suillcient mechanical precision to enable it to operate uniformly, are very severe.

An object of the invention is to provide a solution of these problems and this is accomplished in the present instance by the provision of an improved nozzle for this type of machine by means of which a predetermined and controllable amount of solvent may be applied to a sole and in Just the required position.

In accordance with a feature of the invention,

the illustrated nozzle comprises a plurality of capillary tubes through which the solvent is forced and by which it is applied in threads or ridges occupying approximately parallel separated positions around the margin of a sole.

In common with most machines of this class, the illustrated machine, in which this nozzle is embodied, provides a valve for interrupting the flow of solvent when there is no work in the machine, and it is essential that any material left in the nozzle between the valve and the nozzle outlet shall not run out or drop upon the machine or the pieces of work. Another feature of the invention resides in the provision of an improved nozzle comprising capillary tubes the internal diameter of each of which bears such a relation to the viscosity of the solvent that the capillary action oi the tube on the solvent will retain the solvent in the tube upon removal of the feeding pressure, thus eliminating dripping from the outlet ends of the tubes in the intervals between the presentation of successive pieces of work to the machine. In the illustrated machine,

pressure to extrude the solvent through the tubes is provided by means of a gear pump which, while commercially satisfactory, is liable to relatively large momentary variations in pressure. Accordingly, the length of the capillary tubes of the nozzle is made many times the diameter of each tube. As a result, the frictional resistance provided by the inner walls of the tubes, which increases approximately as the square of the velocity of the stream passing through the tubes, is sumcient to offset the effect of the relatively large momentary variationsin pressure and to reduce to a minimum variations in the quantity of solvent extruded per unit of time. Since the viscosity of the fluid varies with the temperature of the room and for other reasons, it has been found desirable in the illustrated machine to provide a. spring controlled by-pass valve connected across the pump and to include means for varying the spring pressure thereby to control the pressure applied to the solvent. The construction, therefore, enables the threads of solvent to be extruded at a speed equal to or slightly greater than the speed of movement of the work, thus providing for unbroken and substantially uniform threads of solvent.

For a better understanding of the various features of the invention as described in the following specification, reference may be had to the accompanying drawings, in which Fig. l is a perspective view of a machine provided with a nozzle embodying the invention;

Figs. 2 and 3 are vertical sections,- taken in planes at right angles to one another, through a nozzle for use in the machine;

Fig. 4 shows a sole having a band of dried cement and to the upper portion of which threads of solvent have been applied;

Fig. S'shows it treated sole positioned in a soleattaching machine with a shoe held above the sole with the elements somewhat exaggerated. and i Fig. 8 indicates'thecondition which obtains after the shoe has been brought into contact with the-sole and pressure applied, therebyflattening the threads ofso'lvent;

The operating parts-of a'machine embodying my invention are supported in a hollow frame II which may be carried on the head of a column [-2. A receptacle ll secured on the frame III de-' livers viscous solvent through'an outlet pipe ll to a gear pump II. This pump is driven through gears by means of power supplied to a drive shaft. The pump I8 is effective to force the solvent through a passage ina block 24 and to a flexible pipe 2i which is connected to a nozzle 28. A valve is interposed between the nozzle 28 and the pipe 26, and a gage 32 is provided to indicate the pressure. In the block 24 is a by-pass controlled by a spring pressed valve and the pressure at which the solvent is delivered to the nozzle may be controlled by regulating the pressure of the spring against this by-pass valve by turning a knurled head 34 of a screw.

In order that the sole may be fed at a uniform speed past the nozzle 28, the machine is provided with an upper feed roll 36 and a coacting lower feed roll 38. The upper feed roll is mounted on a shaft journaled in an arm 40 which is rigidly mounted upon the frame and extends outwardly therefrom and the lower feed roll is mounted on a shaft journaled in an arm 42 which is supported by. pivot screws so that the arm may tilt.-and the lower feed roll 18 may be dropped (as shown in Fig. 1) to provide for the presentation of a piece of work; or be raised to grip the work rested against the arm 40. The shafts carrying these feed rolls 3i and 38 are driven from the drive shaft 22 by means of gears 46 and are interconnected by gears 48. It is to be'observed that the nozzle 28 is carried in a forked arm ill pivotally mounted upon the arm 40, thus permitting the nozzle to float on the surface of the work. The limit of downward movement of the forked arm carrying the nozzle is determined by a stop screw 52. An edge gage 54 is also mounted on the arm ll and determines the relation of the sole to the outlet openings of the nozzle. Carried upon the arm 42 is a supporting roll which is Joumaled in a carrier ll pivotally mounted upon the arm 42 and held upward resiliently by a spring 6| to a position determined by a stop screw 82. This provides a proper support for portions of non-uniform thickness transversely of the margin, such as shank portions of the sole. The arm 42 has an inward extension 64 through which passes a rod 86 connected, through an intermediate lever N and a rod 12. with a treadle (not shown). The upper end of the rod 68 is joined to a lever it upon a valve rod ll. It is to be observed that the valve rod 18. detachably connected to the valve ill, is provided with universal Joints so that this connection does not interfere with the floating action of the nozzle. A spring ll is interposed between a collar on the rod 6' and a washer resting upon the arm extension ll! When the operator presents a piece of work to the machine and operates the treadle, he will simultaneously raise the lower rolls 3! and II into engagement with the sole and will open the valve permitting a flow of solvent through the nozzle to the work.

In order that the solvent may be applied to the work in ridge-like threads X (Fig. 4) which will be located in just the desired position upon a stripe of dried cement C upon a sole S, I have provided the nozzlewith a series of laterally separated capillary tubes T positioned beside one another. These tubes are manufactured inexpensively and with considerable exactness and I have found that tubes having an internal diameter of 20 to 25 thousandths of an inch, for example, are suitable for the use of the particular solvents having a cellulose derivative which are now employed by the trade. It is essential for cleanliness in the machine and in order that succeeding pieces of work may not be soiled that there shall be no' dripping from the nozzle. This result will be attained with the capillary tubes already described. I have found that by choosing tubes of the proper diameter for use with a solvent of a particular viscosity there will be no dripping from the noz- '21s when the valve is closed. The capillary action of the tubes is responsible for this valuable effect.

The tubes T may be secured in any desired fashion to the pipe 26 leading from the pump, as by mounting the upper ends of the tubes in a 1 block of metal, not shown, but the tubes will be better protected from mechanical displacement if they are mounted in a casing 50 (Figs. 2 and 3), the lower end of which is provided with a groove 92 from which holes are drilled to the interior of the casing. The tubes T are inserted in these holes with their upper ends within the hollow casing and are secured in liquid-tight relation by means of solder 94 filling the groove 92 around the tubes. The lower ends of these tubes are beveled flush with an inclined surface 98 upon the forward side of the nozzle casing while the trailing side is provided with a toe 98 which rests upon the work. The upper end of the casing 00 is secured in a block m detachably secured to the forked arm ill and attached by means of screws (Fig. 3) to a portion of the casing of the valve 30.

As the sole is fed through the machine at a substantially uniform rate, being guided with respect to the nozzle. in such a way that the lower end of the nozzle maintains a uniform relation to the edge of the sole, solvent will be distributed upon the sole in parallel threads X (Fig. 4) of ridge-like formation and deposited in exactly the desiredposition upon the stripe of dried cement C. This construction provides a nozzle by means of which a uniform quantity is extruded per unit of time and, by reason of the uniform feeding of the sole, per unit of area of the cement coated margin. The arrangement greatly simplifies the construction and reduces the cost of manufacture. There is no difilculty in keeping the tubes free and, perhaps partly because of the reduced area of the solvent which is exposed to the air at the outlets of the tubes during the intervals between presentation to pieces of work, there is no dimculty about the continued application, day in and day out, of exactly the desired quantity of material to the work.

The gear pump provides a satisfactory means of applying pressure to the solvent to force it iii fit

10 ameter of a single tube, and is of the order of an inch and-one-half, then the fluctuations in pressure are almost entirely offset, presumably by the frictional resistance provided between the stream of solvent and the inner walls of the tubes.

15 This resistance increases approximately as the square of the velocity of the stream of solvent passing through the tubes and reduces to a minimum variations in the quantity of solvent extruded per unit of time. By regulating the pres- '0 sure of the spring acting on the by-pass valve,

as by turning the screw head 34, it is possible to control the pressure applied and to enable the threads of solvent to be extruded at a speed equal to or slightly greater than the speed of movement 86 of the work, thus insuring unbroken and substantially uniform threads of solvent.

Certain features of the machine illustrated in the drawings are not claimed herein since they are claimed in Letters Patent of the United States so No. 2,042,479, granted June 2, 1936, on the application of Carl A. Newhall.

After the solvent has been applied around the band of cement, the sole is immediately positioned upon a pad Ill forming a unit of the sole at- 36 taching press of the application of Ballard et al.

mentioned above. The condition is somewhat as illustrated in exaggerated dimensions in Fig. 5. The solvent will immediately attack a portion of the cement directly under the threads of solvent and a slight skin will form upon the top of these ridge-like threads X. To the overlasted upper U of a shoe upon the last L there has been applied a band of cement C which is allowed to dry. As soon. however, as the shoe is brought down against member Ill, the threads of solvent will be spread laterally to meet one another and to form a continuous band as indicated at x' in Pig. 8, which will completely cover the bands of cement C and C. Being carefully controlled as to quantity and as to position, the solvent will not spread laterally beyond the conflnes of the bands C and 0' thereby to cause a disadvantageous squeeze-out which is all too common when a liquid solvent is employed.

In usingthe machine, the operator will present a sole to the nozzle with its edge against the gage II and, depressing the treadle, will cause the sole to be gripped between the feed rolls I and II. This same depression of the treadle will open the valve II and allow a flow of solvent through the nozzle. The sole will be guided past the gage substantially automatically by the mechanism more fully illustrated in the Newhall application to which reference has been made above. and a series of stripes x of the solvent will be applied upon the band of dried cement C around such portion oi the margin of the sole as is desired by the manufacturer. Usually, this will include all except part of the heel seat oi the sole. The

treadle is then released and the sole removed from the machine. Release of the treadle shuts the valve Ill and the action of the capillary tubes prevents any dripping from the nozzle.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the so United States is: 1

In a solvent extruding machine of the type in which solvent is forced through a noaxle under fluid pressure which is subject to fluctuation, said nozzle being so positioned as to tend to drip upon as cessation of supply pressure, a shut-oi! valve interpose'd between the pressure-producing means and the nozzle, the discharge means of said nozzle comprising a plurality of capillary tubes relatively positioned "laterally of one another and having 49 their flow passages so proportioned to the viscosity of the solvent to be extruded that be no dripping of solvent from the tubes when said shut-off valve is closed.

a the sole and pressure has been applied through a SEPH W- mf li 45 CERTIFICATE OF CORRECTION.

Patent No. 2,058,461. October 2'7, 1936 JOSEPH w. JOHNSON.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, first column, line 47, strike out the words "rested against the arm line 56, after the numeral "52" 'and before the period insert resting against the arm 40; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record. of the case in the Patent Office.

Signed and sealed this 23rd day of February, A. D. 1937.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.

10 ameter of a single tube, and is of the order of an inch and-one-half, then the fluctuations in pressure are almost entirely offset, presumably by the frictional resistance provided between the stream of solvent and the inner walls of the tubes.

15 This resistance increases approximately as the square of the velocity of the stream of solvent passing through the tubes and reduces to a minimum variations in the quantity of solvent extruded per unit of time. By regulating the pres- '0 sure of the spring acting on the by-pass valve,

as by turning the screw head 34, it is possible to control the pressure applied and to enable the threads of solvent to be extruded at a speed equal to or slightly greater than the speed of movement 86 of the work, thus insuring unbroken and substantially uniform threads of solvent.

Certain features of the machine illustrated in the drawings are not claimed herein since they are claimed in Letters Patent of the United States so No. 2,042,479, granted June 2, 1936, on the application of Carl A. Newhall.

After the solvent has been applied around the band of cement, the sole is immediately positioned upon a pad Ill forming a unit of the sole at- 36 taching press of the application of Ballard et al.

mentioned above. The condition is somewhat as illustrated in exaggerated dimensions in Fig. 5. The solvent will immediately attack a portion of the cement directly under the threads of solvent and a slight skin will form upon the top of these ridge-like threads X. To the overlasted upper U of a shoe upon the last L there has been applied a band of cement C which is allowed to dry. As soon. however, as the shoe is brought down against member Ill, the threads of solvent will be spread laterally to meet one another and to form a continuous band as indicated at x' in Pig. 8, which will completely cover the bands of cement C and C. Being carefully controlled as to quantity and as to position, the solvent will not spread laterally beyond the conflnes of the bands C and 0' thereby to cause a disadvantageous squeeze-out which is all too common when a liquid solvent is employed.

In usingthe machine, the operator will present a sole to the nozzle with its edge against the gage II and, depressing the treadle, will cause the sole to be gripped between the feed rolls I and II. This same depression of the treadle will open the valve II and allow a flow of solvent through the nozzle. The sole will be guided past the gage substantially automatically by the mechanism more fully illustrated in the Newhall application to which reference has been made above. and a series of stripes x of the solvent will be applied upon the band of dried cement C around such portion oi the margin of the sole as is desired by the manufacturer. Usually, this will include all except part of the heel seat oi the sole. The

treadle is then released and the sole removed from the machine. Release of the treadle shuts the valve Ill and the action of the capillary tubes prevents any dripping from the nozzle.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the so United States is: 1

In a solvent extruding machine of the type in which solvent is forced through a noaxle under fluid pressure which is subject to fluctuation, said nozzle being so positioned as to tend to drip upon as cessation of supply pressure, a shut-oi! valve interpose'd between the pressure-producing means and the nozzle, the discharge means of said nozzle comprising a plurality of capillary tubes relatively positioned "laterally of one another and having 49 their flow passages so proportioned to the viscosity of the solvent to be extruded that be no dripping of solvent from the tubes when said shut-off valve is closed.

a the sole and pressure has been applied through a SEPH W- mf li 45 CERTIFICATE OF CORRECTION.

Patent No. 2,058,461. October 2'7, 1936 JOSEPH w. JOHNSON.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, first column, line 47, strike out the words "rested against the arm line 56, after the numeral "52" 'and before the period insert resting against the arm 40; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record. of the case in the Patent Office.

Signed and sealed this 23rd day of February, A. D. 1937.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.

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