JP2000025862A - Liquid containing/dispensing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid containing/dispensing apparatus of a type having a self-supply built-in pump, which is effective in containing and dispensing printing ink for an ink-jet printer. SOLUTION: A diaphragm 24 mounted to a free edge of a peripheral wall 18 of a pumping chamber 16 disposed on a chassis 12 of a liquid containing/ dispensing apparatus 10 is premolded so as to have a protuberent central portion surrounded by a flat edge. When the diaphragm is secured to the free edge of the peripheral wall without forming wrinkles at the flat edge due to the protuberent central portion thereof, the diaphragm 24 is made possible to be deflected with respect to the pumping chamber. The diaphragm 24 has the innermost layer made of an LDPE, and the flat edge of the diaphragm 24 is fixed by heat sticking to the free edge of the peripheral wall of the chassis formed with a plastic material. A crimped ring 26 of aluminum is provided to tightly hold the flat edge of the diaphragm 24 with respect to the free edge of the peripheral wall of the chassis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid storage / distribution device, and more particularly to a self-contained built-in pump (self-contained pump).
(Contained pump). The apparatus of the present invention is useful for storing and distributing printing ink in an ink jet printer.

[0002]

BACKGROUND OF THE INVENTION Pending U.S. patent application Ser. No. 08 / 429,987 (now U.S. Pat. No. 5,784,087; the disclosure of which is incorporated herein by reference) and published European patent application EP 07.
41 038 A2 (the European patent application claims priority from the above-mentioned U.S. patent application) includes a self-contained self-contained self-contained built-in ink jet printer for use in containing and dispensing printing ink. A liquid storage and dispensing device with a pump is disclosed. The pump of the liquid storage and dispensing device has a linearly actuated pumping member reciprocating within a pumping chamber formed by a peripheral wall, the pumping chamber being covered by a thin flexible diaphragm formed of a thin film laminate. ing. The diaphragm is heat staked on the free edge of the peripheral wall surrounding the pumping chamber.

[0003]

However, such a diaphragm has a sufficient amount of material in its center to allow it to flex sufficiently to accommodate the pumping motion of the pumping chamber. The use of flexible diaphragms made from thin film laminates requires great care during heat staking to the peripheral wall of the pumping chamber, as it is left and therefore tends to wrinkle on its outer periphery. Also, the use of heat staking to secure the diaphragm to the peripheral wall caused excessively high temperatures to degrade the membrane used for the diaphragm, while excessively low temperatures degraded the sealing performance between the diaphragm and the peripheral wall. Therefore, great care is required for temperature control.

[0004]

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide an improved liquid storage and dispensing device of the type having a self-contained self-contained pump.
More specifically, an object of the present invention is to provide a liquid storage / distribution device of the above type that is effective for storing and distributing printing ink in an ink jet printer. Also,
It is another object of the present invention to provide an improved pumping chamber cover for use in a liquid storage and dispensing device of the type described above.

[0005]

According to the present invention, there is provided a liquid storage and dispensing apparatus, and more particularly, a liquid storage and dispensing apparatus which is effective for storing and distributing printing ink in an ink jet printer.
A dispensing device is provided that has a pumping chamber cover that does not wrinkle the outer periphery when joined to a free edge of a peripheral wall of the pumping chamber. The invention also relates to a pumping chamber, as described above, on the free edge of the peripheral wall of the pumping chamber.
It has a crimp-type metal ring that assists in fixing the cover, and improves the sealing performance formed between them by heat staking. Eliminating wrinkles in the pumping chamber cover according to the present invention involves preforming the sheet-like cover material by a thermoforming operation, thereby reciprocating the pumping element without requiring excess material on the periphery of the cover. This is achieved by providing a dome-shaped configuration in the center of the cover that provides sufficient flexibility to accommodate movement. In a preferred embodiment of the invention, the cover is formed from a sheet-like material that is a thin laminate of two or more polymer films, between adjacent layers of the laminate, suitable to prevent delamination of the layer. A suitable adhesive is provided.
At least one membrane is made of a material having excellent resistance to oxygen and water vapor transmission, such as ethylene vinyl alcohol copolymer (EVOH), the membrane comprising a laminate having an intermediate layer of low density polyethylene (LDPE). It is preferably used inside the body. LDPE has excellent flexibility and good adhesion to the pumping chamber peripheral wall when the peripheral wall of the pumping chamber and the chassis, which are parts of the liquid storage and dispensing device, are molded from polyethylene by injection molding. ing. In this case, the outermost layer of the pumping chamber cover has a high heat resistance, such as nylon (polyamide material), which has excellent wear resistance and prevents the membrane structure from adhering to the heat staking die. Formed of polymer.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention and its objects, a brief description of the accompanying drawings and the following drawings, the detailed description of the preferred embodiments of the invention and the appended claims are set forth. Please note the description. A liquid storage and dispensing device according to a preferred embodiment of the present invention is generally designated by the reference numeral 10 in FIG. The liquid storage / distribution device 10 is formed of a hard protective shell 12 having one end 12a closed. This end 12a
Is the upper end when the liquid storage and distribution device 10 is attached to, for example, an ink jet printer. Shell 1
A molded plastic chassis 14 is mounted in the open end 12b on the opposite side of the two,
It has a pumping chamber 16 formed and surrounded by a peripheral wall 18 integrally formed therewith.

Disposed within the pumping chamber 16 is a pumping element 20 (a portion of which is shown) that can reciprocate within the pumping chamber 16. A coil spring 22 is provided for biasing the pumping element 20 away from the closed end 12a of the shell 12. The pumping chamber 16 is closed by a cover or diaphragm 24, the outer part of which is heat staked on the free edge of the peripheral wall 18 surrounding the pumping chamber 16. Next, the diaphragm 24 is further fixed to the peripheral wall 18 by the aluminum crimp ring 26, and the seal between the diaphragm 24 and the peripheral wall 18 is used until the life of the ink storage and distribution device 10 is completed.
Maintaining a reliable state is further ensured.

The ink or other liquid deflects the center of the diaphragm 24 against the force of the coil spring 22 to displace the pumping element 20 in the pumping chamber 16, thereby causing the flexible bag ( Not shown, which is dispensed from the liquid storage and dispensing device 10 by pumping liquid from the exemplary arrangement (which is secured beneath the chassis 14 through a fluid outlet portion 28 of the chassis 14). As mentioned above, the liquid containing and dispensing device 10 is disclosed in US patent application Ser. No. 08 / 429,987 (European patent application EP 0 741 038 A).
2), but does not disclose the use of a crimp ring corresponding to the crimp ring 26 of the liquid containing and dispensing device 10 of FIG. In order to provide the diaphragm 24 with a dome-shaped central portion 24a and a flat peripheral portion 24b (this portion is a portion that is heat-staken on the peripheral wall 18 of the chassis 14), the liquid storage and distribution device 10 of FIG.
For example, the apparatus differs from the above-mentioned U.S. Patent Application in that the diaphragm 24 is preformed by a thermoforming operation.
Thus, the diaphragm 24 can be positioned in the central portion 24a without having to overload the material of the peripheral portion 24b, which is required to deflect when pumping ink or other liquid from the liquid containing and dispensing device 10 as described above. A sufficient excess of material can be obtained. If the peripheral material is excessive,
Wrinkling occurs in the diaphragm, which should be flat, which complicates the problem of properly heat staking the diaphragm at the free edge of the peripheral wall of a liquid containing and dispensing device of the type described above. Such wrinkles also cause premature failure of the diaphragm material due to repeated flexing.

As shown in FIG. 2 and more clearly in FIG. 3, diaphragm 24 is formed of a laminate of layers of polymeric material of various compositions. The layer may comprise a polyethylene-based material, such as LDPE, LLDPE, HDPE, metallocene PE, ethylene vinyl acetate, ethylene ethyl acetate, or a blend thereof (preferably having a density in the range of 0.880 to 0.964 g / cc). An innermost layer 24c made of an arbitrary member is provided. All of these materials have high strength and flexibility, and when the chassis 14 is formed of polyethylene, is well heat staked against the peripheral wall of the chassis 14. The diaphragm 24 also has an intermediate layer 24d made of a material having excellent resistance to permeation of gas and water vapor, such as nylon and nylon copolymer, PVD.
C and EVOH. Diaphragm 24 further has an outermost layer 24e of a polymer selected from those having a high melting point, abrasion resistance and flex life such as, for example, nylon and nylon copolymers and polypropylene. As described above, these layers 24c, 24d, 24e
Layers are not well bonded to each other, so these layers 24
Preferably, layers of adhesive 24f, 24g are provided between these adjacent layers of diaphragm 24 to prevent c, 24d, 24e from peeling during operation.

As mentioned above, the diaphragm 24 is preferably manufactured by a co-extrusion method. Because the adhesives used in the coextrusion process usually have a higher molecular weight than the adhesives used in the laminated composite, such high molecular weight adhesives are often used in dry tacky (aggressive) printing inks. This is because they are hardly dissolved. 2 and 3 may give the impression that the diaphragm 24 has a large thickness, but in practice, the liquid containing and dispensing device 10 designed to contain a standard size of 500 ml of printing ink. Diaphragm 24 is 5 mil (0.00
5 inches). As described above, the best mode for carrying out the present invention considered by the inventor has been shown and described as the best mode on the filing date of the present invention. Obviously, suitable changes can be made without departing from the scope of the invention and its legal equivalents only).

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a liquid storage and distribution device according to a preferred embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line 2-2 in FIG.

FIG. 3 is a partial sectional view further enlarging the element shown in FIG. 2;

[Explanation of symbols]

 Reference Signs List 10 Liquid storage / distribution device 14 Chassis 18 Peripheral wall of chassis 24 Diaphragm 24a Dome-shaped portion of diaphragm 24b Peripheral edge of diaphragm 24c Innermost layer of diaphragm 24d Intermediate layer of diaphragm 24e Outermost layer of diaphragm 24f, 24g Adhesive layer 26 Crimp ring

Claims (10)

[Claims] 1. A shell having an open end and an opposite end, and a chassis disposed within the open end of the shell, the chassis having a peripheral wall forming a pumping chamber, wherein the peripheral wall is free. A pumping element having an edge and disposed within the pumping chamber and capable of reciprocating within the pumping chamber, wherein the pumping element is moved from the opposite end of the shell. Further comprising means for biasing away, and a flexible diaphragm covering the pumping chamber, the flexible diaphragm being preformed with a raised central portion and a flat peripheral edge. The liquid storage / distribution device, wherein the peripheral edge is joined to the free edge of the peripheral wall in a sealing manner. 2. The chassis is formed by molding a plastic material, and the diaphragm is formed by a sheet-like co-extruded product or a laminate including an innermost layer of a plastic material heat-stakeable on the chassis. The peripheral edge of the diaphragm is joined to the free edge of the peripheral wall in a sealing manner by heat staking without forming wrinkles in the peripheral edge. Liquid storage described
Dispensing device. 3. The liquid container according to claim 2, wherein the sheet-shaped laminate further has an outermost layer and an intermediate layer, and the intermediate layer has excellent permeation resistance to oxygen and water vapor. Dispensing device. 4. The liquid storage and dispensing device according to claim 3, wherein the intermediate layer is selected from the group consisting of nylon, nylon copolymer, PVDC and EVOH. 5. The liquid containing and dispensing device according to claim 4, wherein the outermost layer is selected from the group consisting of nylon, nylon copolymer and polypropylene. 6. The liquid storage and distribution device according to claim 3, further comprising a first adhesive layer between the innermost layer and the intermediate layer. 7. The liquid storage and distribution device according to claim 6, further comprising a second adhesive layer between the intermediate layer and the outermost layer. 8. The liquid storage and dispensing device according to claim 2, further comprising a thin aluminum crimp ring for fixing and holding a peripheral edge of the diaphragm with respect to a free edge of the peripheral wall. 9. The liquid container according to claim 2, wherein the plastic material of the chassis consists essentially of polyethylene, and the plastic material of the innermost layer of the diaphragm is selected from the group consisting of polyethylene-based members.・ Distributor. 10. The liquid containment of claim 7, wherein the diaphragm has a total thickness, measured in a direction perpendicular to the flat perimeter, substantially no more than 5 mils.・ Distributor.