US3059856A - Applicator for liquid adhesive and folding box machines - Google Patents

Description

Oct. 23, 1962 R. v. PAGENDARM APPLICATOR FOR LIQUID ADHESIVE AND FOLDING BOX MACHINES 6 Sheets-Sheet 1 Filed March 6, 1959 m r Y a md w N W E8 T V T wlm V /w m a m M B Oct. 23, 1962 R, v, PAGENDARM 3,059,856

APPLICATOR FOR LIQUID ADHESIVE AND FOLDING BOX MACHINES Filed March 6, 1959 6 Sheets-Sheet 2 44; A TTORA/E Y Oct. 23, 1962 v, PAGENDARM 3,059,856

APPLICATOR FOR LIQUID ADHESIVE AND FOLDING BOX MACHINES Filed March 6, 1959 6 Sheets-Sheet 5 INVENTOR. R z c/mrd K Pagendarm Oct. 23, 1962 R. v. PAGENDARM APPLICATOR FOR LIQUID ADHESIVE AND FOLDING BOX MACHINES 6 Sheets-Sheet 4 Filed March 6, 1959 JNVENTOR. Ric/lard Z Page/7 darn? R. V. PAGENDARM Oct. 23, 1962 APPLICATOR FOR LIQUID ADHESIVE AND FOLDING BOX MACHINES 6 Sheets-Sheet 5 Filed March 6, 1959 ATTORNEY 1962 R. v. PAGENDARM ,0

APPLICATOR FOR LIQUID ADHESIVE AND FOLDING BOX MACHINES Filed March 6, 1959 6 Sheets-Sheet 6 INVENTOR- Richard V Pagendarm BY MM '9. 64 as;

furrow F hired 3,059,856 APPLICATGR FUR LIQUID ADHESIVE ANT) FULDTNG 30X MAQHINES Richard V. Pagendarm, San Mateo, Calif., assignnr, by mesne assignments, to Atlas General Industries, line, a corporation of Massachusetts Filed Mar. 6, 1959, Ser. No. 797,72 5 Claims. (Qi. 239-117) This invention relates to improvements in devices for applying adhesive to the surface of foldable sheet material, such as box board, paperboard, or paper which is to be adhesively secured to another surface of the same or of a different material.

In the gluing of paper, paperboard, and box board several difficulties are encountered. The board dust which is ever-present in a folding box plant tends to adhere to all parts of the machine carrying exposed adhesive, such as glue wheels, glue nozzles, glue spreaders and the like, interferes with their operation and makes repeated cleaning necessary. Exposed adhesive dries quickly and it is for this reason necessary to remove, or empty and clean, glue applicators, such as glue wheels, when the machine is shut down overnight.

Glue applicators of the paperboard-operated ball-valve type present similar difiiculties because the relatively thin coating of adhesive on the outside of the valves tends to seal the valve ports so tightly, even within short shutdown periods, that thereafter the pressure exerted by the board on the valve elements cannot be depended upon to open the valves when the operation is resumed.

Another problem is the deterioration of adhesive due to oxidation caused by exposure of large surfaces of the adhesive, for example by the large surface of the adhesive coated applicator wheel, to the atmosphere.

Certain gluing operations require the application of a measured quantity of adhesive within a limited portion of a larger area, for example the application of a certain amount of adhesive to a flap in such a manner that no adhesive is deposited within a certain distance from the borders of the flap. It has been proposed to accomplish this by glue wheels having raised portions on a periphery which print adhesive on a limited area only. Wheels of this type make it difficult to control the thickness of the coating and are impractical for the application of quick drying adhesives because the time interval between the application of the adhesive and the completion of the bond is generally too long to prevent partial drying of the adhesive in the interval. Quick drying adhesives are required in fast operating box assembly machines in which there is neither space nor time for an extended application of pressure to the adhesively secured portions.

The invention provides an improved adhesive applicator which overcomes the aforementioned difficulties and limitations. Applicators incorporating the principles of the invention avoid exposure of the adhesive to air prior to the actual application of the adhesive to the board or paper, thereby eliminating the dust and oxidation problem. The invention permits use of very fast drying adhesive composition by depositing the adhesive in slow drying drop or bead form, rather than as a quick drying thin film exposed to air. The drops or beads are converted into the form of a thin film by contact of the surfaces which are to be adhesively secured. This contact takes place under in tea fine high pressure and causes the deposited quantity of adhesive to be spread out as a thin film. The film thus formed is not exposed to air, but only to the action of the surfaces which in most instances are absorbent to the carrier or solvent component of the adhesive.

The invention further provides an assembly in which the adhesive applicator forms a certain prefolding operation of the blank portion to which adhesive is to be applied, so that the blank may thereafter be quickly folded into final box shape, for example by a relatively simple plunger and die mechanism into which the adhesive coated blank is moved.

These and various other objects, features and advantages of this invention will appear more fully from the detailed description which follows accompanied by drawings showing, for the purpose of illustration, a preferred embodiment of this invention. The invention also resides in certain new and original features of construction and a combination of elements hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to be novel will be particularly pointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it may be carried out may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of it in which:

FIG. 1 is a perspective view of a device for converting a flat blank into the form of a glued box, the device comprising four adhesive applicators embodying the invention;

FIG. 2 is a perspective view of the device of FIG. 1 after prefolding of the blank at the instant of application of the adhesive;

FIG. 3 is a perspective view of an adhesive applicator;

FIG. 4 is a perspective view of the adhesive applicator of FIG. 3 after removal of the cover which is shown in inverted position;

FIG. 5 is a perspective exploded view of the device of FIGS. 3 and 4;

FIG. 6 is a plan view, partly in section, of a modified form of the adhesive applicator;

FIG. 7 is a plan view of a modified element of the applicator of FIG. 6; and

FIGURE 8 is a perspective view of the pump actuating mechanism.

In the following description and in the claims various details will be identified by specific names for convenience. The names, however, are intended to be generic in their application. Corresponding reference characters refer to corresponding parts in the several figures of the drawings.

The drawings accompanying, and forming part of, this specification disclose certain specific details of construction of the invention for the purpose of explanation of broader aspects, but it is understood that constructional details may be modified in various respects without departure from the principles of the invention and that the invention may be incorporated in other structural form than shown.

The device shown in FIG. 1 comprises a rigid framework 11 on which a mounting plate 12 is mounted by means of knurled nuts 13.

A main box folding die is composed in the illustrated embodiment by pairs of opposed folding members mounted on the plate 12. A pair of box side wall folding plates 14 and 15 and a pair of box end wall folding plates 16 and 17 define a central die aperture 18 of substantially rectangular outline. Each of the folding plates comprises a substantially horizontal portion as seen, for example, at 19 and a downwardly curved portion 20 bordering the die aperture, using plate 17 as an example. The horizontal portions are provided with suitable apertures 21 through which mounting bolts 22 extend into the mounting plate 12. The side wall forming plates 14 and 15 are further provided with apertures 23 through which spring urged fingers 24 extend. The purpose of these fingers is to prevent withdrawal of a box from the die aperture 18 in an upward direction.

A pair of pressure plates is arranged below the end wall folding plates 16 and 17. Only one of these plates is visible at 25. The pressure plates are movable towards, and away from, each other by an appropriate linkage of levers operated by a hydraulic servo-motor 26 in the framework 11. The servo-motor consists basically of a cylinder 27 subdivided into two chambers by a piston. Hydraulic lines 28 and 29 lead to the two cylinder chambers and permit the opposite pressure plates to be moved towards each other with great force of the order of several tons for the purpose of exerting compressive force on the box supported by a plunger 30 visible above the die 18. As will later be seen, the plunger is movable into and out of the die and acts as a box supporting mandrel or block.

F our adhesive applicators 31, 32, 33, and 34 are mounted on the plate 12 in substantially symmetrical arrangement with respect to the die aperture 18. Taking the adhesive applicator 32 as an example, each applicator comprises a base or bracket 35 supporting the applicator housing 36 at a slant with respect to the mounting plate 12 to which the bracket is secured by bolts 37. As a result of the slanted mounting of the housing the front wall 38 of the housing extends at an angle 02 with respect to the vertical, and the front walls 38 of oppositely mounted housings present a funnel or V into which a box blank may be pressed.

The front walls are provided with a plurality of adhesive discharge apertures 39 arranged in a predetermined pattern, as is best seen by inspecting the front wall 38 of the applicator 34. The individual discharge apertures 39 are controlled by suitable valve elements later to be described in greater detail. At this point it will be suificient to note that certain or all of the discharge apertures may either be opened to permit discharge of adhesive therethrough, or be closed to maintain the interior of the housing 36 sealed from the atmospheric air.

Flexible ducts 4-0 extend to the individual applicators and supply them with adhesive from a reservoir 41 seen at the far right in FIG. 1. A duct 42 extends from the reservoir to a suitable pump preferably of the positive displacement type (not shown) which is periodically operated and feeds measured quantities of adhesive to the four applicators for discharge through their individual apertures or nozzles 39. Each aperture thus discharges a droplet of adhesive, the size of the droplet being adjustable by adjustment of the pump.

The plunger 30 is attached to vertical plunger rods 43 which are reciprocated in a vertical direction to move the plunger into and out of the die in such a manner that the plunger may dwell in the die for a short period during which compressive force is applied by the pressure plate 25 against a box supported by the plunger. The plunger 30 has vertical grooves 44 in it which provide clearance for the spring urged fingers 24 so that the fingers will not interfere with the movement of the plunger out of the die, but will merely grasp the box on the plunger and prevent its upward withdrawal.

A blank feeder 45 is visible behind the plunger 30 and comprises suction cups 46 adapted to grip a box blank B for the purpose of removing the blank from a magazine 47 (see FIG. 2) and depositing the blank above the die aperture, as will presently be described.

The blank B comprises a main panel M, outer end panels E and corner flaps F extending from the side panels S not visible in FIG. 1 but seen in FIG. 2.

The action of the blank feeder 45 is so timed with respect to the action of the plunger 30 that the feeder deposits a blank above the die when the plunger is withdrawn and moves out of the way of the plunger when the plunger enters the die in its downward stroke. In the position in which the plunger is shown in FIG. 1, the plunger is on its upward stroke while the feeder 45 is about to swing the blank B from its originally nearly vertical position into a horizontal position above the die. It will be noted that the feeder 45 comprises two substantially parallel rails 48 whose outer edges are spaced slightly less than the distance between the front walls 38 of the adhesive applicators measured at the narrowest point.

The geometry of the feeder mechanism is such that the blank B is swung into horizontal position at a certain distance above the four adhesive applicators 31, 32, 33 and 34, whereafter the feeder performs a downward motion as a result of which the rails 4% move between the slanted front walls 38 of the applicators and cause the corner flaps F to be folded into a slanted position with respect to the side panels S which remain substantially fiat and horizontal. The folding operation is assisted and accurately controlled by the rails which engage the blank immediately adjacent the folding scores along which the flaps F are articulated to the side panels S.

In order to assist the folding operation and reduce friction between the adhesive applicators and the blank, the front edge of the cover plate 49 is rounded at 50 to present a curved or cam surface. It Will be noted that this cam surface lies at a level appreciably above the horizontal portions of the box end wall folding plates 16 and 17 and may thus be considered portions of a prefolding die in advance of the main folding die constituted by the downwardly curved portions 20 of the main folding die.

In the position shown in FIG. 2 the flaps F are either parallel to, and in full contact with, the front walls 38 of the adhesive applicators and thus rest on the discharge apertures, or they are spaced very slightly from the discharge apertures as a result of the setting of the slant of the adhesive applicators so that the flaps F contact the front walls 38 immediately adjacent the curved portions '50 and are spaced from the lower portion of the front walls including the discharge apertures very slightly by a distance of the order of a millimeter or less. The adjustment of the setting of the adhesive applicators is accomplished by moving opposite applicators either towards or away from each other and by adjusting the slant of the brackets 35. The first adjustment is possible by reason of oversize holes in the brackets 35 through which the bolts 37 extend. The latter adjustment is possible by shimming up the portion of the bracket to which the housing 36 is attached.

When the feeder 45 deposits the blank B on the die, as a result of which the four corner flaps F are folded into an upwardly slanting position, the feeder releases the blank and moves out of the way of the plunger 30 which is about to descend. During this phase the blank B is locked in the die by four catches 51 mounted adjacent the front walls of the adhesive applicators. Each catch 51! comprises an angle bracket 52 bolted to the mounting plate 12 at 53. The bracket 52 carries a stud on which a lock plate 55 is pivoted. The lock plate is under the action of a spring 56 which normally pulls the plate into projecting position and causes it to snap over the edge of the side wall S of the blank thereby locking the blank in place above the die aperture.

When the plunger descends and strikes the main panel M of the blank, the blank moves into the die aperture in such a way that the side walls S are folded into upward position against the sides of the plunger first whereby the flaps F, to which a predetermined amount of ad hesive was applied by the applicators, move over the end surfaces of the plunger. The end panels of the blank are then folded over the corner flaps to complete the blank folding operation. When the plunger 30 has reached its lowest position in the die, compressive force is exerted against the end panels whereby the adhesive is spread between the fiaps F and the end panels E as a very thin film which sets almost immediately.

Application of adhesive to the flaps F takes place shortly after the flaps F are folded into upwardly slanted position by the feeder and before the plunger 39 engages the blank. Each discharge aperture 39 of the applicators discharges a droplet of adhesive. These droplets are applied in a pattern which is preferably of such outline that no droplets are deposited within a marginal zone of the flaps F. In FIG. 2 the area within which adhesive is applied is indicated by a broken line at 57. The purpose of maintaining a marginal area free from adhesive is to prevent adhesive from being squeezed out beyond the boundaries of the flaps F When compressive force of the order of several tons is applied against the end walls of the box. Such excess adhesive would soil the machine and interfere with its operation.

The detailed construction of the adhesive applicator is apparent from FIGS. 3 to 5.

Referring first to FIG. 4 showing the cover 49 of the applicator removed and inverted to show its underside, the housing 36 contains a main base 58 supporting a plurality of pins 59 adapted to enter the discharge apertures 39 within a first area I. For this purpose the main base 58 may be moved towards the front wall 38 until its pins enter and seal the apertures 39. Preferably the length of the pins 59 and the freedom of motion of the main base 58 are such that the pins penetrate the discharge apertures fully so as not to leave any accumulation of adhesive therein which might dry and clog the aper tures. The pins thus act both as valve elements and as cleaning elements for the discharge apertures 39. The main base 58 is moved towards and away from the front wall 38 by an eccentric '60 on a shaft 61 extending through the cover plate and carrying a knurled knob 62. The knob has a pointer 63 readable against indicia 64 to indicate the extent to which the discharge apertures 39 within the front wall are open or closed.

A second base 65 carries pins 59 within a second area II and a third base 66 carries similar pins to control discharge apertures within a third area III. The second and third bases 65 and 66 are movable relatively to the main base 58, but their movement is restricted. Referring to FIG. 5, the base 65 is provided with a pin 67 engaging an elongated aperture 68 in the main base 58 and the third base 66 comprises a similar pin 69 engaging a similar, but longer, elongated aperture 70 in the main base. Springs 71 and 72 are placed between the ends of the second and third bases and a shoulder 73 on the main base. The springs urge the respective second and third bases into a position in which their pins close to their respective discharge apertures 39.

When the knob 62 is turned, the main base 58 is actuated directly by the eccentric 6t} engaging a recess 60 in the main base. Starting with the position in which all the aperture 39 are closed, rotation of the knob 62 to the right causes the main base 58 to move away from the front wall 38, thereby withdrawing its pins from the apertures within the area I which are then open. The springs 71 and 72 maintain the second and third bases 65 and 66 in the position in which their respective pins 59 seal the apertures within areas II and III until, upon further rotation of the knob, the main base i withdrawn so far that the pin 67 reaches the end of the elongated shorter aperture 68. The second base then follows the main base, and the apertures within the second area II are opened.

At this time the pin 69 of the third base has not yet reached the end of the elongated longest aperture 70 and the discharge apertures within area III remain sealed until, upon further rotation of the knob 62, the main base 58 is withdrawn so far that it takes the third base 66 with it, whereafter all the apertures 39 within the front wall 38 become operative as discharge nozzles.

The illustrated arrangement permits variation of the area of application so that it is not necessary to exchange adhesive applicators when the machine is changed over to handle a larger or a smaller box.

When the machine is shut down, even for brief periods, the operator simply turns the knob 62 of the applicators into the position in which all the dischargeapertures are closed. This prevents oxidation of the adhesive and also prevents drying of adhesive within the apertures. By turning the knobs in the opposite direction the applicators are rendered operative. The force available for opening and closing the apertures is considerably greater than the force available in conventional valved applicators responsive to the passage of a blank past the applicator. The force which may be exerted by a blank is small and the setting of conventional valved applicators is critical in that slight missetting results in inoperativeness of the mechanism.

FIG. 6 illustrates a modified form of applicator in which only one base 153 is provided. The base ha an elongated aperture or cam way 66' for engagement by the eccentric 60. The front wall 138 of the housing ran has three portions 74, 75 and 76 of different thickness. The apertures 39 within the area I are controlled by pins 59 securely mounted in the base 158. The apertures 1139 Within area 11 are controlled by pins 159 and apertures 239 within area III are controlled by pins 259. In order to provide for an equal resistance to flow of the adhesive through the respective apertures, the diameter of the holes and pins within the portion 74 of the least wall thickness may be made smaller than the diameter of those of the intermediate portion 75. The diameter of the apertures 239 and their corresponding pins 259 within the thickest wall portion 74 may be made even larger than the corresponding diameters within the intermediate portion 75.

FIG. 7 illustrates a further modification in which the base 258 is stepped at its pin carrying end, so that the protruding portion of the pins 59 of the smallest diameter is shorter than the protruding portions of the pins 159 and 259 of the larger diameter.

In the foregoing description only those portions of the mechanism which are essential for an understanding of the claimed invention have been described in detail. A detailed description of other elements of the mechanism such as the actuating mechanism of the feeder 45, the actuating mechanism of the plunger 36, and the actuating mechanism of the box compressing mechanism will be found in the copending application Serial No. 797,688, filed March 6, 1959, now Patent No. 3,038,389, dated June 12, 1962.

The actuating mechanism of the pump for feeding adhesive is shown in FIG. 8. A platform 163 is tiltably mounted on the framework 11 by means of an eccentric pivot 164 held in a bracket 165. The eccentricity of the pivot permits the end of the platform 163 nearest the observer to be raised and lowered for the purpose of adjustment. The adjustment is facilitated by a pointer 166 movable relatively to, and readable on, a setting dial 167 on the bracket 165. The far end of the platform 163 has a downwardly extending follower bracket 168 carrying a roller 169. The roller bears against the periphery of a pump actuating cam (not visible) on the main shaft of the machine. The cam has an elevated portion which lifts the roller 169' and causes the platform 163 to be tilted upwardly once for each revolution of the shaft 23.

A rail 172 is welded to the platform 1.63 at 173 and supports a carriage 174 which is slidable lengthwise with respect to the rail 172. A pneumatic servo-motor 175 is mounted on the platform 1.63 and comprises a cylinder within which a spring urged piston is movable to slide the carriage towards the observer under spring action, whereas vacuum applied to the line 178 results in movement of the piston in the opposite direction. The carriage E74 is connected to the servo-motor piston by a pin 179. The carriage 174 has a top surface 186 which is slidable into and out of engagement of an actuator 181 of a glue pump 18?, connected to the reservoir 41 of adhesive by the adhesive supply ducts 115.

When vacuum is applied to the servo-motor 175 through the line 178, the servo-motor moves the carriage in a direction away from the observer so that an upward tilt of the platform 1.63 causes the top surface 1% to engage the glue pump actuator. As a result, adhesive is pumped to the glue heads and is discharged through their respective discharge apertures The volume of adhesive may be varied by adjusting the pump stroke. When the eccentric pivot 164 is set high, more adhesive is pumped than when the pivot is set low. The dial 167 may there fore be calibrated in volumetric units.

A signal is derived from the pneumatic blank feeder for con-trolling the operation of the glue pump in such a manner that adhesive is discharged only when a blank is fed to the die, whereas the feeding of adhesive is interrupted when the supply of blanks is in terrupted.

Further details of the no-blank-no-glue mechanism are explained in the aforesaid copending application Serial No. 797,688, now Patent 3,038,389, dated June 12, 1962, but need not be described here.

What is claimed is:

1. An applicator for liquid adhesive, the applicator comprising, in combination, means forming a chamber enclosed by walls, at least one wall having a plurality of bores therethrough forming discharge nozzles, said nozzles being distributed over a certain wall area and adapted to discharge adhesive in a pattern, a portion of said Wall comprising certain nozzles being thicker than the remainder of the wall comprising other nozzles; a plurality of pins adapted to he moved into and out of said bores; a common base within said chamber for aid pins for moving said pins into and out of the respective bores jointly; means operable from the outside of the chamber for moving said base towards, and away from, said wall, the stroke of movement being suflicient for said pins to extend through said bore to the front of said wall in one extreme position, to withdraw the pins from said bores in the other extreme position, and to withdraw fully the pins from the bores of said certain nozzles while still leaving other pins inserted in said other nozzles in an intermediate position; and means for supplying adhesive under pressure into said chamber.

2. An applicator for liquid adhesive, the applicator comprising, in combination, means forming a chamber enclosed by walls, at least one wall having a portion of a certain thickness and another portion of a lesser thickness, said wall having a plurality of bores therethrough forming discharge nozzles, the bores within said certain portion being of a larger diameter than the bores within said other portion; a plurality of pins adapted to be moved into and out of said bores, the pins for said larger bores being thicker than the pins for the smaller bores; a common base within said chamber for supporting said pins, said base being movable towards, and away from, said wall to move said pins into and out of the respective bores jointly, the length of the pins being such that upon movement of said base away from said wall the smaller bores are exposed first to permit a discharge of adhesive therethrough, the larger bores being exposed upon additional movement of said base away from said wall; means operable from the outside of the chamber for moving said base towards, and away from, said wall; and means for supplying adhesive under pressure into said chamber.

3. An applicator for liquid adhesive, the applicator comprising, a housing including a front wall, said front wall having a plurality of bores therethrough forming discharge nozzles, certain of said bores representing a limited discharge pattern, other bores representing a supplemental discharge pattern; a plurality of pins adapted to be moved into and out of said bores; a main base mounted within said housing for movement towards, and away from, said wall, said main base supporting the pins associated with said certain bores; a second base mounted within said housing for movement towards, and away from, said wall, and for movement relatively to said main base, said second base supporting the pins associated with said other bores; spring means between said main base and said second base for urging said second base in a direction towards said Wall; means for limiting the freedom of movement of said second base relatively to said main base; means operable from the outside of said housing for moving said main base towards, and away from, said wall to insert the pin into, and withdraw the pins from, said bores; and means for admitting adhesive under pressure into said housing.

4. An applicator for liquid adhesive, the applicator comprising, a housing including a front wall, said front wall having a plurality of bores therethrough forming discharge nozzles, a first group of said bores representing a first discharge pattern, a second group representing a second discharge pattern, and a third group representing a third discharge pattern; a plurality of pins adapted to be moved into and out of said bores; a main base mounted within said housing for movement towards, and away from, said wall, said main base supporting the pins associated with the bores of the first group; a second base mounted within said housing for movement towards, and away from, said wall and for freedom of movement relatively to said main base, said second base supporting the pins associated with the bores of said second pattern; a third base mounted within said housing for movement towards, and away from, said wall and for freedom of movement relatively to said main and second base, said third base supporting the pins associated with the bores of said third pattern; spring means between said main base and said second base and between said main base and said third base for urging said second and third bases towards said wall; means for limiting the freedom of movement of said second base relatively to said main base; means for limiting the freedom of movement of said third base relatively to said main base, the limitation of the freedom of movement of the second and third bases being unequal; means operable from the outside of said housing for moving said main base towards, and away from, said wall to insert the pins into, and withdraw the pins from, their respective bores; and means for admitting adhesive under pressure into said housing.

5. An applicator for liquid adhesive, the applicator comprising, a housing including a front wall, said front wall having a plurality of bores therethrough forming discharge nozzles, certain of said bores representing a limited discharge pattern, other bores representing a supplemental discharge pattern; a plurality of pins adapted to be moved into and out of said bores; a main base mounted within said housing for movement towards, and away from, said wall, said main base supporting the pins associated with said certain bores; a econd base mounted within said housing for movement towards, and away from, said wall, and for movement relatively to said main base, said second base supporting the pins associated with said other bores; spring means between said main base and said second base for urging said second base in a direction towards said wall; means for limiting the freedom of movement of said second base relatively to said main base; a shaft extending into said housing from the outside; an eccentric on said shaft inside said housing, said eccentric engaging said main base, the stroke of the eccentric being sufficient to move said main base into the position in Which its pins close the respective bores in one extreme position and open the bores in the other extreme position; manually operable means mounted on said shaft on the outside of the housing for turning said shaft; and means for admitting adhesive under pressure into said housing.

References Cited in the file of this patent UNITED STATES PATENTS 1,018,020 Werner Feb. 20, 1912 11) Krumsiek et al July 29, Evans May 23, Falcon Feb. 12, Engstrum Sept. 22, Sinclair Sept. 11, Nickin et a1. Apr. 15, Martin July 29, Gusmer et al June 16, Gibbs July 28, Burke Sept. 22,

FOREIGN PATENTS Switzerland May 15,

Images