US3162337A - Flow control plunger assembly - Google Patents

Description

Dec. 22, 1964 SABAKA 3,162,337

FLOW CONTROL PLUNGER ASSEMBLY Filed NOV. 15, 1965 FIGURE l FIGURE 2 GEORGE SABAKA mvzrnon BY fiamy/ j), MW

- ATTORNEY United States Patent 3,162,337 FLOW CONTROL PLUNGER ASSEMBLY George Sabalka, RD. 3, Hanover, Pa. Filed Nov. 15, 1963, Ser. No. 324,026 1 Claim. (Cl. 222327) The present invention is broadly concerned with plungers for feeding or expelling material from a container. The present invention is more particularly concerned with a plunger, especially a plunger assembly which is adapted for controlling the flow of viscous, mastic-like or semi-fluid materials such as, for example, a caulking compound from the cartridges or containers in which such materials are sold or dispensed.

Thus, the present invention is more particularly concerned with a caulking gun and cartridge therefor, and relates to a caulking assembly that utilizes a disposable cartridge having a dispensing spout at one end thereof and a piston at the other end thereof.

Caulking guns that employ disposable cartridges are Well known in the art and generally comprise a gun which supports the cartridge and which is provided with a lever actuated plunger that is adapted to engage and move the cartridge piston of the disposable cartridge toward the spout. Thus, movement of the cartridge piston exerts pressure on the caulking material within the cartridge and displaces the caulking material through the dispensing spout of the cartridge. However, an annoying problem encountered with this type of caulking assembly is that, when the assembly is set aside after use or between uses, the caulking material remaining in the cartridge expands and thus oozes or drips from the spout. This is evidently due to the relatively high compressibility and relatively slow recovery of the caulking material. It might also be due to some extent, especially with a paper cartridge, to a slight swelling of the cartridge body. The expansion of the caulking material, during use, from the spout builds up pressure in the cartridge with resulting compression of the material which, unless permitted to expand within the cartridge, will subsequently expand through the spout.

This is particularly annoying since, when the gun is set aside, the caulking material or compound which remains in the cartridge oozes and drips on the table or other support upon which it is placed, creating an untidy and undesirable situation.

Various expedients have been used heretofore to prevent the caulking compound or other semi-fluid material from thus oozing or dripping from the spout. For instance, the use of a flexible diaphragm among other things have been proposed. However, none of these have proven satisfactory since the diaphragm has a tendency to adhere to the compound and cannot overcome this adherence sufficiently or quickly enough to prevent the oozing or loss of compound from the dispensing spout. Moreover, in all cases where such a diaphragm has been employed, no provision has been made for the release of the air which is confined between the diaphragm and the caulking compound so that it becomes extremely difiicult to actuate the diaphragm with any degree of efiiciency.

The present invention is concerned with a unique caulking assembly whereby positive control can be exerted on the remaining material within the caulking gun when it is not in use to positively control and prevent the flow or seepage of material from the gun. The present invention in particular comprises an integrated assembly comprising the plunger of the gun and the movable piston element of the disposable cartridge.

In essence, the piston element movable within the cartridge is a cuplike cylindrical element, the diameter of which is substantially equivalent to the inner diameter of the disposable cartridge, having sufficient tolerance to 3,152,337 Patented Dec. 22, 1964 permit the piston to move within and through the cartridge and to substantially prevent any leakage of the compound behind the piston. The piston has a circumferential skirt element extending rearwardly substantially vertical from about the circumference of the base. The distance that the skirt element of the piston extends from the base element of the piston may vary appreciably, but is generally in the range from about A" to /3" to The distance the skirt element extends rearwardly from the base of the piston may be varied depending upon related conditions such as upon the diameter of the base.

In accordance with the present invention, ears or lugs or projections extend inwardly from the skirt element of the piston. These may be attached by any means desirable, but are preferably punched lugs or ears which are secured by punching from the outer surface of the skirt element of the piston. These extending projections which extend inwardly from the skirt element are sufliciently distant from the flat surface of the base of the piston so as to permit engagement of the plunger of the gun as hereinafter described. Generally it is preferred that these projections be from to A5" to A" distant or away from the flat surface of the base element of the piston.

As pointed out heretofore, the gun is substantially a conventional one wherein the piston of a cartridge is caused to move through the cartridge by a plunger element of the gun which is actuated by a lever and a ratchet assembly. Any type of ratchet assembly may be used as, for example, one described in US. Patent 2,889,085 issued June 2, 1959; inventor: H. B. Collins; entitled Drive Means for Caulking Gun Plungers.

In accordance with the present invention, the plunger element of the gun is actuated by the ratchet assembly of the gun. This plunger element is a disclike metallic element and contains a number of cuts around the periphery thereof which are of a dimension or depth to permit the disclike plunger to pass by the projections of the piston skirt and to seat securely on the base of the piston. Orientation to permit this passage can be secured by rotating the cylindrical dispensable cartridge to the desired spot or alignment of the projections with the cuts or indentations. When it is desired that no further caulking is necessary, the handle controlling the plunger rod is rotated disengaging the notches from the ratchet or plunger rod and, at the same time, moving the nonindented portion of the plunger edges behind the protruding ears of the piston. A backward thrust can then be exerted on the handle, pulling back the plunger and the piston from the nozzle, thereby creating a positive thrust of air in a negative direction through the nozzle and thereby actually causing the mastic or caulking compound to move backwardly within the cartridge itself.

The apparatus assembly of the present invention may be particularly understood by reference to the drawings illustrating one embodiment of the same. FIGURE 1 shows the gun and the cartridge, and the cartridge piston and gun plunger within the cartridge in a nonengaged position. FIGURE 2 shows the gun plunger and cartridge piston in a locked or engaged position whereby as a rearward thrust is exerted on the handle a rearward thrust will be exerted on the piston by the plunger causthe piston to move away from the cartridge nozzle.

Referring specifically to the drawing, a caulking gun I is shown having disposed therein a dispensible cartridge 2 having a dispensing nozzle or equivalent means 3 at the front end thereof. The cartridge 3 is positioned in caulking gun I in a conventional manner; namely, by thrusting the same rearwardly within housing 4 of gun I and then permitting the nozzle 3 to seat in slot 5 and to be locked therein by housing 6 of the caulking gun. Movable piston element 7 comprising a piston base 8 and a backwardly extending piston skirt 9 is shown approximately halfway through the disposable caulking cylinder 2 or container 2. Punched inwardly from piston skirt 9 of the piston 7 are projections 10 which are a distance above or away from piston base 8. The gun plunger element or disc 11 is actuated by means of plunger rod 14 having notches 12 and a ratchet assembly 13, in conjunction with lever 21 (not shown in detail), within handle 1. Plunger or disc 14 is shown disposed a distance apart from the piston 7 in a nonengaged position. Plunger 11- contains'a number of peripheral notches 15 or in-,

dentations which will permit the placing of plunger 11 on piston base element 8 of piston'7 by permitting the protrusions or projections 10 to pass through the notches --When it is no longer desired to utilize, the gun, gun or plunger rod 14 is rotated by means of handle approximately 180. This places the slots 15 in nonalignment with the ratchet in the handle; This rotative'rnovement disengages notches 12 of gun or plunger rod 14-,from the ratchet assembly andpermits free movementof' the plunger hind projections 10 of the piston skirt.v It is to be noted that rotation of handle 20 approximately -180..disengages the notches of the plunger rod from the ratchet and, at

the same time, rotates plunger 11 in a manner to seat and narrow nozzle of the material when not in use, thereby preventing hardening of the material and subsequent chokingof the nozzle. 7

What is claimed is:

, An assembly whichcornprises in combination, a disposable cylindrical cartridge containing a viscous'material,

rod backwardly' since it is not engaged in the ratchet assembly. j 7

The rotative movement, as-pointed out,-- also places 7 slots 15 of the disc or plunger 11 in nonaxial alignment with projections 10 of piston skirt=9, therebyplacing pro jections 10 in direct contact with theback surface of plunger 11. e e e Upon exerting a backward thrust on handle 20, plunger rod 14 will move freely to the rear, causing plunger 11 to move to the rear and also causing piston 7 to move toward the rear by means of the thrust exerted by the back surfaceofplunger 11 on the projections 10 of skirt, 9.

This positive-effort and thrust will cause' air to back-1 flow through nozzle 3, thereby clearing this nozzle of the havinga spout at one end and "an :axially movable piston element at the. other end; and a gun which supports the cartridge provided with an axial movableplunger and in-' cluding'a'plunger rod containing indentations about part of its circumference for meshing with meansffor incrernentally advancing said plunger; rod and said plunger, said piston element being characterized by having a piston base and a'circumferentially backwardly extending piston skirt, said pistonskirt' containing projections and perforatio ns both formed by portionsjof the skirt being punched V with saidprojections extending inwardly from said piston mastic or caulking compound and causing the same to.

move into the main body of the cylinder. This has two extremely desirable features.

terial or caulking compound, and also effectively clears nozzle 3 of caulking compound and mastic material. ;As

is well known in the art, the retention of arelatively small amount of caulking compound in a narrow area such as a nozzle 3 causes this material to harden and, in many instances, makes it extremely diificult to use the cartridge subsequently. V r a 'The number of projections and slots on the piston and plunger may be varied appreciably,dcpending upon the other features of the assembly. However, it is preferred that the notches and slots approximate from about 2' to 6, preferably about 3. The exten'tto which the projections v In the first place, it prevents oozing and seeping of the mastic ma- 5 skirt, distant from said piston base; said plunger being characterized by containin'gfa number of indentations about itsperiphery so as to permit said plunger to pass by'said projections and bear against said piston base, meansfonrotating said plunger and said plunger rod so 'as to secure a no nalignm'ent between. said indentations and said projections and to secure a demeshing of the indentations of'the plunger rod from said means for increl mentally advancing said plunger rod and said plunger,

whereby"as"said plunger is withdrawn rearwardly, said projections bear against the top surface of said plunger causing said piston element'to move rearwardly within are extended within the skirts of the piston may be .also

varied appreciably; They should be of sufiicie'nt length so as to have the necessary mechanical strength to avoid shearing of the same upon exerting a backward thrust upon the'piece which is interlocked. FIGURE '2, as pointed out heretofore, shows the plunger 11 engaged in piston 7 be- "said cartridge causing; air to backflow through said spout. m

References Cited by th'eExaminer UNITED STATESPATENTS RAPHAEL'M. LUPO, Primary Examiner; i

Lou s DEMBO, Examiner;

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