US 3140078 A
Description (OCR text may contain errors)
July 7, 1 964 D. C. KRAHE ETAL MIXING AND DISPENSING DEVICE Filed June 15. 1961 INVENTORS: #525527 621/55 DOA/4L0 C. IKE/WE f A TTOENEYS United States Patent 3,140,078 MIXING AND DISPENSING DEVICE Donald C. Krahe and Herbert E. Grubb, San Carlos, Calif, assignors, by mesne assignments, to Adhesive Engineering Company, a corporation of California Filed June 15, 1961, Ser. No. 117,305 2 Claims. (Cl. 259-47) This invention relates to a device for storing, mixing and dispensing a two part composition. Such compositions must be kept separate until just prior to the dispensing operation and they must be mixed thoroughly before they can be used. Although the invention is primarily applicable to an inexpensive throw-away mixer and dispenser, the device can be cleaned and reused. The device of the present invention is particularly useful with an epoxy resin wherein a catalyst must be mixed with the resin and the mixture used almost immediately but it can be used in any situation wherein two components must be mixed just prior to use.
It is therefore an object of the present invention to provide a simple yet effective device wherein a two-component mixture may be stored with the components separated until just prior to use whereupon the two components can be thoroughly mixed and then dispensed.
Other objects and features of the invention will be apparent from the specification which follows.
In the drawings forming part of this application:
FIGURE 1 is a perspective view, with certain parts cut away, of a device embodying the present invention;
FIGURE 2 is an enlarged side view, partially in section, of a device embodying the present invention;
FIGURE 3 is a section on the line 33 of FIGURE 2 showing the piston;
FIGURE 4 is a section on the same line as FIGURE 3 but showing the piston in open position;
FIGURE 5 is an exploded view of an alternate form of piston and FIGURE 6 is a partial view of a device embodying the invention utilizing the piston of FIGURE 6.
Referring now to the drawing by reference characters, there is shown in FIGURES 1 through 4 a storage, mixing and dispensing device generally designated 8 having a cylindrical chamber 10 one end of which is provided with a dispensing nozzle 12 which is closed by a removable cap 14. At the opposite end of cylinder 10 is an end plate 16 having a central boss 18 adapted to receive a piston rod 20. The boss 18 may be provided with an O ring 22 to insure a tight seal. Further, the end 16 is provided with a small vent opening 24 which is normally closed with a snap-01f fitting 26. The piston rod is provided at one end with a knob 28 so that it can be easily manipulated while the opposite end is provided with the composite piston generally designated 30.
The composite piston 30 is composed of two parts, namely a first disc 32 of a relatively hard plastic which may be formed as part of or rigidly affixed to piston rod 20 and the second disc 34 of a relatively soft plastic, such as polyethylene, which has a lip 36 on its periphery so that the discs 32 and 34 are held by the lip 36 in face-toface engagement yet are free to turn relative to each other. The disc 32, of hard plastic, has at least one pro jection 38 on its periphery while the disc 34 has at least one slot 40 located within the lip 36. Thus, the projection and slot limit the rotational movement possible between the discs. The disc 32 has a series of openings 42 therein while the disc 34 has corresponding openings 44. It will be understood that the openings 42 and 44 correspond with each other while the solid portions between the openings, respectively 48 and 50, are slightly larger than the openings so that when the piston is in the closed position, as is illustrated in FIGURE 3, there will be a slight overlapping of the solid portions 48 and 50 of the two discs.
3,148,878 Patented July 7, 1964 The openings are made as large as possible, while retaining the sealing possibility, so that when the discs are in the open position shown in FIGURE 4, the openings through the piston will be as large as possible. It will also be understood that the length of the slot 40 will determine the amount of movement possible between the two pistons and that the length of this slot, minus the width of a projection 38 will determine the relative motion. Further, although six openings have been shown in each of the pistons, the number of openings might be decreased in which the slot 30 would become larger or the number of openings might be increased in which case the slot would be made shorter. Further, instead of using a single projection 38 and single slot 40, the entire periphery of two pistons can be provided with mating projections and slots.
In FIGURES 5 and 6 there is shown an alternate embodiment wherein a piston rod 52 has attached thereto a first disc 54 having a series of slots 56 therein. The rod 52 extends beyond the disc 54 as at 58 and has a small slot 60 therein. A second disc 62 is provided with an annular slot 64 which is adapted to receive an O-ring 66. A small radial hole 68 leads from the slot 64 to the bearing hole 70 in the center of the disc. The bearing hole 70 is of such size that the disc can turn freely on the rod extension 58. The device is assembled as is shown in the FIGURE 6. The disc 62 is placed on the end of the shaft 58 and a pin 74 is placed in the hole 68. The O ring 66 is then placed in the slot 64, the O-ring serving the dual purpose of holding the pin 74 in place and providing a substantially fluid-tight seal with the piston wall 76. It will be noted that in this case the leading face 78 of the second disc 62 is made convex to conform with the configuration of the front wall 80 of the injection device so that there will be no dead space, insuring a complete mixing of the contents as well as complete ejection.
Turning now to a description of the operation of the device it will be noted in FIGURE 2 that the cylindrical portion is divided by the piston into two chambers 82 and 84. In dealing with many compositions it will be desirable to have the two chambers of equal size although the size relationship can be altered by moving the piston. The device will be assembled and filled as is shown in FIGURE 2 with the composite piston in its closed position with one of the components in the chamber 82 and the other of the components in the chamber 84. For instance, the chamber 84 might be filled with a setting catalyst for an epoxy resin while the chamber 82 is filled with the resin itself. The device would be stored and sold in this condition. When the user wished to utilize the composition he would rotate the handle 28 slightly to move one disc relative to the other. There is sufficient friction between the forward disc and the cylinder so that when the rear disc rotates the forward disc will tend to remain stationary. The piston would then be worked back and forth a number of times thoroughly mixing the contents of the compartments 82 and 84. After mixing is complete, the handle 28 would be retracted to its extreme rear position and given a slight rotational movement to close the piston. The cap 14 would then be taken off and the air vent 24 opened by breaking off the small projection 26. The contents would then be expelled by pushing on the handle 28. The contents might be expelled at one time or might be expelled a small amount at a time over a considerable period, the period being determined by the setting rate of the particular plastic employed.
It is believed apparent from the foregoing that we have provided a simple yet effective device which serves as a storage chamber, a mixing chamber and dispensing device for a two-component plastic. Although after expelling the contents the device might be cleaned and refilled, nor mally the device is so inexpensive that it would be discarded after a single usage.
3 i We claim: first disc being loosely secured in the said channel for 1. A storage, mixing and dispensing device for a tworotation relative to said second disc, said first and component mixture comprising: second discs being held in a unitary relationship sole- (a) a cylinder having a discharge opening at one end ly by means of said channel, said second disc having thereof and a normally sealed air inlet at the opposite 5 an integral rod at the center thereof extending through end with a snap-off fitting for opening said vent; and the end of the cylinder opposite the discharge open- (b) a normally closed piston dividing the cylinder into ing, said rod having a handle on the exposed end two chambers, said piston being formed of a first and thereof. a second disc each having holes therein, said holes be- 2. The structure of claim 1 wherein the said collar has ing in registration when said discs are in a first posi- 10 an internal groove and the first of said discs has a tongue tion and forming a solid piston when the first of said along the periphery thereof adapted to register with the discs is rotated to a second position relative to the said groove, the size of the said groove being such as to persecond of Said discs, the first of said discs being of a mit the discs to be rotated relative to one another suifidiameter slightly less than the interior diameter of ciently far that in a first position said holes are in registrathe said cylinder and the second of said discs having 15 tion and in a second position said holes are not in reg- 'a cylindrical collar securedat right angles thereto at istration, thus forming asolid piston. the extreme outer edge thereof, said collar passing between said first disc and the internal wall of the said R f r n Cited in the fil f this pa en cylinder, said collar having an integral lip parallel UNITED STATES PATENTS to the said second disc extending from the said collar inwardly toward the center of said disc whereby said 20 ggg ggg fi'g 'g lip and said collar together with said second disc 2,571,542 Collins Oct. 16, 1951 form a channel for the receipt of said first disc, said