JP5619469B2 - Valve mechanism, ink storage container - Google Patents

Description

  The present invention relates to a valve mechanism and an ink storage container that stores ink having the valve mechanism therein.

  Examples of ink storage containers include ink tanks for writing instruments and ink (tank) cartridges for inkjet printers. In response to the amount of ink consumed for writing and printing to form letters and images, outside air is taken into the tank and the air is exchanged so that changes in atmospheric pressure in the tank do not adversely affect ink consumption. Examples of the mechanism include a mechanism in which a simple hole is formed as an outside air intake port, and a mechanism in which an air passage with a valve mechanism that allows only ventilation but does not allow liquid to pass therethrough.

  However, if a simple hole is provided as an outside air intake, ink from this hole may leak. In addition, in the case where only a film that allows gas to pass but does not allow liquid to pass is disposed, the inside of the ink cartridge becomes the same as the atmospheric pressure, and thus ink may blow out from the ejection port. Therefore, it is necessary to hold an ink by disposing an ink occlusion body such as a sponge on the ink discharge port.

  However, when ink is held by an ink storage body such as a sponge as described above, the amount of ink retained is smaller than that of an empty ink storage section that does not have an ink storage body, and printing is performed by reducing the amount of ink in the same volume. The number decreases.

  Therefore, as disclosed in Patent Document 1 or 2, for example, an ink storage container has been proposed in which an air flow rate control unit capable of controlling the air flow rate is built in the upper lid of the storage container. According to this ink storage container, it is possible to avoid a decrease in the amount of ink retained as compared with the case where the ink occlusion body is arranged inside the container, and further, the air flow control unit makes the inside of the container have a negative pressure. Therefore, it is possible to prevent the ink inside from being easily blown out from the discharge nozzle.

  Further, as disclosed in Patent Document 3, a valve using an elastic member that does not have a through hole is disposed inside the ink cartridge, and a negative pressure generation dedicated space is provided on one surface side of the elastic member. A valve mechanism has been proposed in which an ink supply dedicated space is formed on the other surface to control ink supply by deformation of an elastic member.

JP 2001-277777 A Japanese Patent No. 4246787 Japanese Patent No. 3991853

  The ink storage container described in Patent Document 2 and the like is basically extremely excellent, and since the atmospheric pressure in the container is appropriately maintained at a negative pressure, stable printing is possible. On the other hand, according to an unknown experiment conducted by the present inventors, this type of ink storage container has a structure for controlling ink discharge indirectly by controlling the flow rate on the air side. For example, if the ink suction force on the printer side increases, there is a risk that ink will be excessively discharged.

  Further, the valve mechanism of Patent Document 3 has a problem that the valve structure is complicated because it is necessary to provide a space exclusively for negative pressure generation and a space exclusively for ink supply.

  The present invention has been made to solve such problems, and while maximizing the utilization efficiency of the ink storage space in the ink storage container, it suppresses excessive discharge of ink, etc. The main object of the present invention is to provide an ink storage container that can reliably perform stable ink ejection control from a slight change in atmospheric pressure to a large change in atmospheric pressure, including troubles on the printer side.

The present invention that achieves the above object is a valve mechanism that is disposed in an ink storage container and disposed between an ink storage part and an ink discharge part, and is configured as an elastically deformable film and penetrates therethrough. An elastic valve having a hole; a negative pressure forming space disposed on the downstream side of the elastic valve and communicating with the ink ejection unit; and disposed on the upstream side of the elastic valve and communicating with the ink storage unit. An ink supply space that supplies ink to the elastic valve side, a blocking portion that is disposed on the ink supply space side and contacts the elastic valve and blocks between the ink supply space and the through hole, and the negative electrode A spring disposed on the pressure forming space side, biasing the elastic valve toward the ink supply space side to abut the blocking portion and the elastic valve; and a spring disposed on the negative pressure forming space side. When the valve is displaced downstream, And the displacement restricting portion for restricting a displacement amount of the elastic valve abuts, wherein the the displacement restricting portion, flow communicating the said through hole negative pressure forming space in a state where said elastic valve abuts A path is formed, and the negative pressure applied to the negative pressure forming space causes the elastic valve to be displaced downstream against the bias of the spring, and the blocking portion and the elastic valve are separated from each other, In the valve mechanism, ink flows from the ink supply space to the negative pressure forming space through the through hole.

  The valve mechanism that achieves the above object is further characterized in that one end of the spring is held by the displacement restricting portion.

  The displacement restricting portion of the valve mechanism that achieves the above object further includes a circular protrusion that fits inside the spring and holds one end of the spring.

  In the valve mechanism that achieves the above object, the clearance between the displacement restricting portion and the elastic valve is set to 3 mm or less in a state where the elastic valve is biased by the spring and is in contact with the blocking portion. It is characterized by that.

  In the valve mechanism that achieves the above object, the clearance between the blocking portion and the elastic valve is set to 2 mm or less in a state where the elastic valve is in contact with the displacement restricting portion against the spring. It is characterized by that.

  In the valve mechanism that achieves the above object, the inner diameter of the through hole is set to 1.5 mm or less.

  The elastic valve of the valve mechanism that achieves the above object is further characterized in that an annular thick part surrounding the outer periphery of the through hole is formed.

  The thick portion of the valve mechanism that achieves the above object is further characterized by being fitted inside the spring and holding the other end of the spring.

  The valve mechanism that achieves the above object is further characterized in that the maximum outer diameter of the thick part is set to 2 mm or more.

  The blocking portion of the valve mechanism that achieves the above object further includes an annular blocking protrusion that surrounds the vicinity of the outer periphery of the through hole of the elastic valve, and the inner diameter of the spring is equal to the outer diameter of the blocking protrusion or It is characterized by being set large.

  The ink supply space of the valve mechanism that achieves the above object further includes an ink suction port that is arranged close to the bottom surface of the ink storage unit.

  The present invention that achieves the above object includes the valve mechanism according to any one of the above, and an air flow rate control unit that is provided above the ink storage unit and controls an air flow rate between the inside and the outside. Ink storage container.

  The air flow rate control unit of the ink storage container that achieves the above-described object can further be elastically deformed so that air is not normally circulated, but air is exchanged with the outside in accordance with a change in internal pressure of the ink storage unit. A continuous porous valve body, and a liquid repellent film body that is disposed closer to the ink storage unit than the valve body and has air permeability and has been subjected to water repellent treatment. .

  The ink storage container that achieves the above object further includes a movement valve that moves up and down by an urging force from an external member in the ink discharge section provided below the ink storage section, and the movement valve moves up and down. The ink discharge / stop is switched.

  According to the present invention, it is possible to obtain an excellent effect that the supply of ink can always be stabilized.

It is sectional drawing which shows the structure of the ink storage container which concerns on embodiment of this invention. It is sectional drawing of an air flow control part. It is a perspective view of each member with which an air flow control part is provided. FIG. 4A is a cross-sectional view along the horizontal direction of the valve mechanism in a closed state, and FIG. 4B is a cross-sectional view along the vertical direction. It is a top view which shows the 2nd plate of a valve mechanism. It is sectional drawing along the (A) horizontal direction of the valve mechanism in an open state, (B) The sectional view along the vertical direction.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. In addition, the case where the ink storage container in each of the following embodiments is applied to an ink cartridge for an ink jet printer will be described as an example.

  FIG. 1 is a cross-sectional view showing the structure of an ink storage container 100 according to this embodiment. The ink storage container 100 is made of a suitable synthetic resin, and as shown in the figure, the flow rate of air is controlled between the ink storage unit 10 that stores the ink M inside and the inside and outside of the ink storage unit 10. An air flow rate control unit 20, an ink discharge unit 30 for controlling the discharge of the ink M stored in the ink storage unit 10, and a valve mechanism 70 disposed between the ink storage unit 10 and the ink discharge unit 30. It is configured.

<Ink storage unit>
The ink storage unit 10 includes a hollow main body 11 having an open top and an upper surface 12 that is combined at the top as a lid that closes the opening of the main body 11. The main body 11 is formed in a substantially rectangular parallelepiped shape having a depth dimension smaller than the vertical and horizontal dimensions in the figure. An ink discharge unit 30 is provided at the bottom of the main body 11.

  The top surface portion 12 has a top plate 12a that is a horizontally long rectangular plate in plan view (when viewed from above), and a fitting wall 12b that protrudes downward from a slightly inner bottom surface of the periphery of the top plate 12a. It is composed of The upper surface portion 12 is combined with the main body portion 11 by fitting the fitting wall 12 b into the main body portion 11.

<Air flow control unit>
As shown in FIG. 1, the top plate 12 a of the upper surface portion 12 is provided with an air flow rate control unit 20 in the vicinity of the longitudinal end portion on the right side of the drawing. FIG. 2 is a cross-sectional view of the air flow rate control unit 20. As shown in the figure, the top plate 12a of the upper surface portion 12 is formed with a recessed portion 12e having a circular cross section that is depressed, and the air flow rate control portion 20 is a valve body accommodated in the recessed portion 12e. 22, a water repellent film body 24, a pressing ring 26 and a cap 28 are provided. The air flow rate control unit 20 places the water-repellent film body 24 in the recess 12e, places the pressing ring 26 thereon, and further places the valve body 22 thereon, and from above these The cap 28 is fitted into the recess 12e, and the valve body 22, the water repellent film body 24, and the pressing ring 26 are sandwiched between the cap 28 and the recess 12e.

  The bottom 12f of the recess 12e is formed with a circular cross-sectional conduction port 12g communicating with the inside 13 of the ink storage unit 10 at the center thereof. The conduction port 12 g is formed so that the inner diameter increases toward the inside 13. Note that the water repellent treatment may be applied to the inner surface and the peripheral edge of the conduction port 12g. By applying the water-repellent treatment, the ink adhering to the inner surface and peripheral edge of the conduction port 12g or the lower surface of the water-repellent film body 24 is efficiently dropped to obstruct the plugging of the conduction port 12g or the water-repellent film body 24 in advance. Can be prevented.

  A water repellent film seating portion 12h and a lower end receiving portion 12i are provided around the conduction port 12g of the bottom portion 12f. The water repellent film body seating portion 12h is an annular recess (annular step) that positions and receives the water repellent film body 24. The lower end receiving portion 12i is an annular groove provided concentrically on the outer periphery of the water repellent film body seating portion 12h, and has a structure for receiving the lower end of a peripheral surface portion 28b of the cap 28 described later.

  The water repellent film body seating portion 12h is formed of an olefin resin material and is formed as a smooth surface. When the water repellent film body 24 is seated on the water repellent film body seating portion 12h, the water repellent film body seating portion 12h is formed. 24 is set so as to increase the degree of adhesion to the water-repellent film body seating portion 12 h and to prevent the ink M from entering between the contact surfaces as much as possible. In particular, since the olefin resin material has low wettability, the water repellent effect is high. Therefore, when the water repellent film body 24 is in close contact, the ink cannot enter the gap. In addition, although there exist various raw materials, such as a polypropylene and polyethylene, as an olefin resin, a polypropylene is employ | adopted in this embodiment.

  Between the water repellent film body seating portion 12h and the lower end receiving portion 12i, an annular ridge portion 12j protruding upward in the drawing is formed. The protruding portion 12j is positioned so that the water-repellent film body 24 is not displaced in the lateral direction, and also functions as a guide for smooth entry of the peripheral surface portion 28b of the cap 28.

  FIG. 3 is a perspective view of each member provided in the air flow rate control unit 20. As shown in the figure, the valve body 22 is a substantially disk-shaped flat plate made of an elastic material in which a plurality of micropores communicate with each other, and is configured by using a material such as polyurethane as a compressed porous body.

  In the normal state where there is no pressure difference between the inside 13 and the outside of the ink storage unit 10, the valve body 22 is blocked from air permeability and does not enter and exit air, but if a pressure difference greater than a predetermined value occurs, It is extended by minute elastic deformation, which causes the micropores to be expanded and air permeability is generated, so that air flows from the high pressure side to the low pressure side, so that the function of controlling the air flow rate is exhibited. It is configured.

  That is, the air flow rate control unit 20 changes the amount of air passing through the plurality of fine holes of the valve body 22 according to the pressure difference between the outside and the inside 13 of the ink storage unit 10, and this change causes ink storage from the outside. It has a function of controlling the air flow rate to the inside 13 of the unit 10. In addition, the material of the valve body 22, a structure, etc. are not specifically limited, As the valve body 22, what was disclosed by the said patent document 1 and a commercial item are employable.

  In this embodiment, the valve body 22 is a compression body so as not to have air permeability when compressed. In other words, the communicating porous body made of an elastic material is compressed until air permeability is lost, and the compressed porous body is formed so that the air flow rate control function can be exerted more. In such a compressed porous body, a large number of irregular spaces formed by smashing and folding the elastic body constituting the communicating porous body are formed inside, but in the compressed state, the air permeability is lost. . However, since a large number of irregular spaces formed in the compressed porous body communicate with each other, when a pressure difference between the inside and outside occurs, the space is compressed from the outside due to a pressure difference greater than a predetermined pressure generated by the extension of the valve body 22. Air is pushed into the inside of the porous body, and the air deforms the valve body while expanding the air holes connecting the networked space in the compressed porous body, so that the opposite side of the compressed porous body, that is, the ink reservoir. By moving to the inside 13 side of 10, air permeability is produced.

  This air flow rate (air flow rate) is determined by the ease of passage of the space networked in the compressed porous body. Therefore, when the pressure difference is large, the valve body 22 extends greatly, and the air is passed through the space networked in the compressed porous body. Becomes easier to pass, and the air flow becomes larger. On the other hand, when the pressure difference is equal to or greater than the predetermined pressure difference and the pressure difference is small, the valve element 22 extends small, the amount of air passing through the space networked in the compressed porous body is reduced, and the air flow rate is reduced. When the pressure difference decreases due to ventilation by the valve body 22, the valve body 22 also contracts, and the ventilation amount decreases. Further, when the pressure difference is less than the predetermined pressure difference, the valve body 22 is compressed again, so that the air permeability of the valve body 22 is lost. As described above, since the air flow amount also depends on the magnitude of the atmospheric pressure difference, it is possible to quickly and appropriately adjust the atmospheric pressure within the ink storage unit 10 to be constant.

The degree of the pressure difference between the outside (atmosphere) and the inside of the ink storage unit 10 may be determined by appropriately selecting the degree of communication, the degree of compression, etc. For example, when the pressure difference is 20 mmH ₂ O or less, there is no air permeability, and when the pressure difference is 20 mmH ₂ O or more, the air pressure difference is preferably compressed so as to have air permeability.

  The elastic material constituting the valve body 22 is sufficient if it has a plurality of micropores and passes through the micropores in a stretched state, and examples thereof include polypropylene, various rubbers, and various elastomers. In the case of a continuous porous body, a rubber and / or plastic raw material is mixed with an inert gas, a decomposable foaming agent, and a volatile organic liquid, and foam is formed by forming bubbles inside to form a continuous pore. And a rubber / plastic raw material in which inorganic particles such as calcium carbonate are kneaded and formed into a plate shape, and then the inorganic particles are eluted to form continuous pores. As raw materials, elastic materials such as natural rubber, styrene butadiene rubber, acrylonitrile butadiene rubber, chloroprene rubber, neoprene rubber, polyvinyl chloride, polyethylene, polypropylene, acrylonitrile butadiene, polystyrene, polyamide, polyurethane, silicone resin, epoxy resin, phenol resin , Urea resin, fluorine resin, etc. It is. Among these, ether-based polyurethane resins and the like are preferable in view of durability against liquids, ease of formation of a continuous porous body, productivity, and the like.

  The elastic material constituting the valve body 22 is stretched when a pressure difference acts, and the pressure difference decreases when ventilating, and finally returns to the original state, and even when there is no ventilation, the first compressed state without air permeability is always present Is preferably maintained. For this purpose, the compression set is preferably excellent in compression set characteristics. In this compression, the compression rate is preferably 5% or more and 40% or less of the thickness of the material before compression, and thus, when the pressure difference is less than a predetermined value, it is easy to be surely blocked.

  The water repellent film body 24 is a substantially disk-shaped flat plate made of a water repellent material having air permeability. In this embodiment, a breathable water-repellent material is used as the material of the water-repellent film body 24, but the present invention is not limited to this, and the ink component is prevented from contacting the waterproof material and the valve body 22. As long as it is a film to be used, a material having a large critical surface tension may be used. Further, the air permeability may not be necessary when the membrane does not block the entire conduction port 12g and at least a part thereof penetrates.

  The water-repellent material used in the present embodiment may be a material that itself has air permeability. In particular, a water repellent material having a critical surface tension of 25 dyn / cm or less is preferable. As such a material, various resin films and inorganic films are used, and fluororesin, fluororubber, and the like can be preferably used, and Teflon (registered trademark), that is, polytetrafluoroethylene (PTFE) is more preferable. It is.

  The water repellent film body 24 has a plurality of fine holes communicating in consideration of air permeability, and the diameter of the plurality of fine holes is preferably 5 μm or less, more preferably 0.1 μm or less.

  The pressing ring 26 is a so-called donut-shaped flat plate in which a through hole 26a having a substantially circular cross section is formed at the center of a substantially circular flat plate. In the present embodiment, an air layer 29 (see FIG. 2) is formed between the water repellent film body 24 and the valve body 22 by forming the pressing ring 26 into a donut shape. This air layer is preferable because the air layer 29 is present even if it passes through the water-repellent film body 24, so that the ink M stored in the ink storage unit 10 can be prevented from reaching the valve body 22.

  In the present embodiment, the so-called donut-shaped pressing ring 26 is illustrated, but the present invention is not limited to this, and a structure that can form the air layer 29 can be used instead. That is, any member shape and arrangement that can form an air layer between the water repellent film body 24 and the valve body 22 can be substituted. In the present embodiment, as described above, since the valve body 22 is pressed uniformly, it is preferable to use the hollow substantially disk-shaped pressing ring 26.

  In addition, the pressing ring 26 is formed using metal as a material in the present embodiment. As a result, the smoothness of the upper and lower surfaces of the pressure ring 26 is increased, and a uniform surface pressure acts on the valve body 22 and the water repellent film body 24 to increase the close contact between the contact surfaces, thereby leaking ink. It is possible to prevent.

  The cap 28 is formed of a resin material having an appropriate rigidity, and includes a disk-shaped ceiling portion 28a and a cylindrical peripheral surface portion 28b extending in the axial direction from the periphery thereof. The ceiling portion 28a is formed with an annular valve body seating portion 28c having a flat surface at a position facing the water repellent film body seating portion 12f (the lower surface in the figure), and the valve body seating portion 28c includes three pieces. A vent hole 28d is provided.

  Returning to FIG. 2, the corners on the inside of the ceiling portion 28 a and the peripheral surface portion 28 b of the cap 28, in other words, the peripheral edge on the lower surface side of the ceiling portion 28 a (the root on the inner peripheral side of the peripheral surface portion 28 b) are formed thin. An elastic hinge P is provided. In this way, the peripheral surface portion 28b is easily elastically deformed with the hinge P existing near the outside of the circular protrusion 28f forming the valve body seating portion 28c as a base point. Further, the lower end of the peripheral surface portion 28b is formed so as to be in contact with the lower end receiving portion 12i.

  In the present embodiment, the lower end abuts on the lower end receiving portion 12i, so that the pushing amount of the cap 28 is limited to a constant value, and the air flow control unit 20 is prevented from being forcibly compressed. That is, the lower end of the peripheral surface portion 28a functions as a stopper that temporarily comes into contact with the lower end receiving portion 12i when the cap 28 is attached to the recess 12e. As a result, it is possible to prevent an overload from acting on the valve body 22 and the water repellent film body 24 at the time of assembly, and the function of the air flow rate control unit 20 from being deteriorated.

  After the assembly is completed, the cap 28 is urged upward by the restoring force of the valve body 22 and the water repellent film body 24, and there is a slight gap between the lower end of the peripheral surface portion 28a of the cap 28 and the lower end receiving portion 12i. Gaps are formed. In this way, when the cap 28 is attached to the recess 12e, the valve body 22, the pressing ring 26, and the water repellent film body 24 are attached to the valve body seating portion 28c of the cap 28 and the water repellent film body seating of the recess 12e. It can be held between the portions 12h with an appropriate pressure.

  That is, the air flow rate control unit 20 is made elastically deformable, so that the communicating porous valve body 22 can perform positive and negative bidirectional air exchange with the outside in accordance with a change in the internal pressure of the ink storage unit. On the other hand, the pressure ring 26 is disposed so as to contact the ink M side, and further, the water repellent film body 24 is disposed so as to contact the ink M side of the pressure ring 26. Further, a gap for elastic deformation of the valve body 22 is formed on both outer sides of the valve body 22 in the air passage direction, and the water repellent film body 24, the pressing ring 26, and the valve body 22 are held under pressure. It becomes.

<Ink ejection part>
Returning to FIG. 1, the ink ejection unit 30 includes a cylindrical projecting portion 31 formed to project outward (downward in the drawing) on the bottom surface of the main body portion 11, and an inner side (see FIG. A cylindrical cylinder 34 protruding toward the upper side). An insertion hole 15 having a circular cross section is formed inside the protrusion 31. The insertion hole 15 has an inverted mortar shape that decreases as it advances toward the cylinder 34. A guide hole 34 a is formed inside the cylinder 34. The insertion hole 15 and the guide hole 34a are continuous in a coaxial state.

  A movement valve 33 is disposed inside the insertion hole 15 and the guide hole 34a. Since the movement valve 33 has a gap (play) between the insertion hole 15 and the guide hole 34a, the ink supplied through the guide hole 34a is held around the movement valve 33. The moving valve 33 moves along the guide hole 34a on the cylinder 34 side and is guided in the vertical direction. A ring-shaped seal member 32 is provided at the lower end of the insertion hole 15 (projection 31). Further, a coil spring 35 that urges the moving valve 33 toward the seal member 32 is accommodated in the guide hole 34a on the cylinder 34 side. The upper end of the coil spring 35 is in contact with the bottom of the cylinder 34, and the lower end of the coil spring 35 is engaged with the moving valve 33. As a result, the moving valve 33 is guided in the axial direction by the guide hole 34 a and is always urged toward the seal member 32 by the coil spring 35.

  The seal member 32 is a substantially cylindrical member and is made of an elastic material such as rubber. The seal member 32 is fixed by being press-fitted into the insertion hole 15. The upper end of the seal member 32 protrudes inward in the radial direction, and the lower end of the moving valve 33 contacts. When the moving valve 33 is pushed in from the outside against the force of the coil spring 35, this contact state is released and the ink around the moving valve 33 is discharged from the seal member 32 to the outside. When the ink cartridge is set in the printer, the contact state is always open. Further, when printing is performed on the printer side, negative pressure is applied from the printer side to the ink ejection unit 30 to suck the ink M.

<Valve mechanism>
A valve mechanism 70 is disposed in the vicinity of the upper end of the cylinder 34. The valve mechanism 70 includes an ink suction port 74 disposed in close proximity to the bottom surface of the ink storage unit 10 and an ink outflow path 72 connected to the cylinder 34. When a negative pressure is applied to the inside of the valve mechanism 70 from the ink discharge section 30 via the ink outflow path 72, the valve in the valve mechanism 70 is opened, and the ink M is sucked up from the ink suction port 74, and the ink is discharged. Ink M is supplied to the ink ejection unit 30 via the outflow path 72. On the other hand, when the application of the negative pressure from the ink ejection unit 30 side is stopped, the valve inside the valve mechanism 70 is closed and the supply of the ink M is mechanically cut off.

  4A is a cross-sectional view along the horizontal direction of the valve mechanism 70 in the closed state, and FIG. 4B is a cross-sectional view along the vertical direction of the valve mechanism 70 in the closed state. The valve mechanism 70 includes an elastic valve 76, a first case 78, a second case 80, a negative pressure forming space 82, an ink supply space 84, a spring 86, a displacement restricting portion 88, and a blocking portion 90.

  The elastic valve 76 is a circular thin film made of an elastic material such as silicon, and a holding portion 76A having an annular thickness is formed on the outer peripheral edge, a through hole 76B is formed in the center, and the through hole 76B is surrounded. An annular thick portion 76C is formed. The inner diameter of the through hole 76B is set to 1.5 mm or less, desirably 1.0 mm or less, more preferably 0.8 mm or less. In this embodiment, it is 0.8 mm. Further, the elastic valve 76 has a bent portion 76D formed in the circumferential direction between the holding portion 76A and the thick portion 76C. The bent portion 76D is bent so as to protrude in a U-shaped cross section in the axial direction. Therefore, the elastic valve 76 can expand and contract in the radial direction, and the flexibility at the time of elastic deformation is enhanced.

  The first case 78 is a substantially circular plate material, and is disposed in parallel to and upstream of the elastic valve 76. An annular first connection protrusion 78A is formed on the outer peripheral edge of the first case 78, and the first connection protrusion 78A engages with a second case 80 described later. An annular first valve fixing projection 78B is formed on the radially inner side of the first connecting projection 78A in the first case 78, and bites into and engages with the holding portion 76A of the elastic valve 76. Further, a blocking portion 90 is formed at the center of the first case 78, that is, at a location facing the through hole 76 </ b> B of the elastic valve 76. The blocking portion 90 contacts the periphery of the through hole 76B. A space formed by the elastic valve 76 and the first case 78 is defined herein as an ink supply space 84. Accordingly, when the blocking portion 90 and the elastic valve 76 come into contact with each other, the ink supply space 84 and the through hole 76B are blocked, and the supply of the ink M is stopped. On the other hand, when the blocking portion 90 and the elastic valve 76 are separated from each other, the ink supply space 84 and the through hole 76B are communicated, and the ink M is supplied.

  In the vicinity of the lower edge of the first case 78 arranged along the vertical direction, an ink suction path 78C is formed to suck up the ink M. That is, the ink supply space 84 communicates with the ink storage unit 10 through the ink suction path 78C. As described above, since the ink suction port 74 formed at the lower end of the ink suction path 78C is disposed in close proximity to the bottom surface of the ink storage unit 10, the ink suction port 74 and the ink suction path 78C. The ink M is sucked into the ink supply space 84 via the.

  The second case 80 is a substantially circular plate material, and is disposed in parallel to and downstream of the elastic valve 76. An annular second connection protrusion 80 </ b> A is formed on the outer peripheral edge of the second case 80 and engages with the first connection protrusion 78 </ b> A of the first case 78. An annular second valve fixing protrusion 80B is formed inside the second connecting protrusion 80A in the second case 80 in the radial direction. The peripheral edge of the elastic valve 76 is sandwiched in the circumferential direction by the first valve fixing protrusion 78B of the first case 78 and the second valve fixing protrusion 80B of the second case 80.

  Further, a displacement restricting portion 88 is formed at the center of the second case 80, that is, at a location facing the through hole 76 </ b> B of the elastic valve 76, and abuts the periphery of the through hole 76 </ b> B of the elastic valve 76. Here, the space formed by the elastic valve 76 and the second case 80 is defined as a negative pressure forming space 82. As will be described in detail later, the displacement regulating portion 88 is provided with a spring 86, and the spring 86 biases the thick portion 76 </ b> C of the elastic valve 76 toward the blocking portion 90 of the first plate 78. When negative pressure is applied to the negative pressure forming space 82, the elastic valve 76 is elastically deformed toward the negative pressure forming space 82 against the bias of the spring 86, and the thick portion 76C is moved toward the second case 80 side. It moves and abuts against the displacement restricting portion 88. As a result, the displacement amount of the thick portion 76C is limited by the displacement restricting portion 88.

  The ink outflow path 72 connected to the cylinder 34 is formed in the vicinity of the side portion of the second case 80 arranged along the vertical direction. That is, the negative pressure forming space 82 communicates with the cylinder 34 of the ink discharge unit 30 through the ink outflow path 72.

  The blocking portion 90 formed on the first plate 78 includes an annular blocking protrusion 90A that protrudes toward the elastic valve 76 side. The blocking protrusion 90A has a partially conical inclined surface 90B whose diameter gradually decreases toward the elastic valve 76 side. The protruding end of the blocking protrusion 90A comes into contact with the elastic valve 76 so as to surround the periphery of the through hole 76B. Compared with the case of surface contact, the pressure of the contact portion is increased by bringing the blocking protrusion 90A into line contact with the elastic valve 76. As a result, the blocking force between the ink supply space 84 and the through hole 76B is increased. Further, the diameter of the protruding end of the blocking protrusion 90A is set to be larger than the inner diameter (0.8 mm) of the through hole 76A, while being set to be substantially equal to or less than the inner diameter of the spring 86. Specifically, since the inner diameter of the spring 86 is about 2.5 mm, the diameter of the protruding end of the blocking protrusion 90A is set within a range of 0.8 mm to 2.5 mm. In this embodiment, it is set to about 2 mm. By doing in this way, since the thick part 76C of the elastic valve 76 urged by the spring 86 is deformed along the inclined surface 90B of the blocking protrusion 90A, the mutual adhesion is improved.

  As shown in FIG. 5, the displacement restricting portion 88 formed on the second plate 80 is a circular protrusion that protrudes toward the elastic valve 76 side. The protruding end surface 88E of the displacement restricting portion 88 abuts the through hole 76B and the thick portion 76C of the elastic valve 76, thereby restricting the amount of displacement of the thick portion 76C. Further, the displacement restricting portion 88 is formed with an annular groove 88A, and a range surrounded by the annular groove 88A is a circular central protrusion 88D. Since the outer diameter of the outer peripheral wall of the central projection 88D (the inner diameter of the annular groove 88A) is set slightly smaller than the inner diameter of the spring 86, the central projection 88D is fitted inside the spring 86. One end of the spring 86 is held. Since the outer diameter of the thick part 76C of the elastic valve 76 is set slightly smaller than the inner diameter of the spring 86, the thick part 76C is fitted inside the spring 86 so that the other end of the spring 86 is fitted. Is held. That is, the outer diameters of the thick part 76C and the central protrusion 88D are set to be substantially the same.

  As shown in FIG. 4, the spring 86 biases the thick portion 76 </ b> C of the elastic valve 76 toward the shut-off portion 90, so that when the thick portion 76 </ b> C comes into contact with the shut-off portion 90, The blocking protrusion 90A bites into the thick portion 76C by about 1 mm. In this state, the gap between the elastic valve 76 (thick part 76C) and the projecting end face 88E is set to 5 mm or less, preferably 3 mm or less, and is 3 mm here. As shown in FIG. 6, when the thick portion 76C of the elastic valve 76 and the blocking portion 90 are separated from each other and the thick portion 76C comes into contact with the displacement regulating portion 88, the elastic valve 76 (thick portion 76C) and The gap between the protruding ends of the blocking protrusion 90A of the blocking portion 90 is set to 4 mm or less, preferably 2 mm or less, and is 2 mm here.

  One inner slit 88B extending in the radial direction is formed inside the annular groove 88A of the displacement restricting portion 88. In addition, four outer slits 88C extending in the radial direction are formed at intervals of 90 degrees in the circumferential direction on the outer side of the annular groove 88A of the displacement restricting portion 88. The inner slit 88B and the outer slit 88C function as a flow path for the ink M flowing from the through hole 76B of the elastic valve 76 to flow out from the displacement regulating portion 88 to the negative pressure forming space 82 side.

  Next, the operation of the ink storage container 100 will be described.

  As shown in FIG. 1, when the ink M is stored in the ink storage unit 10 and is set in an inkjet printer (not shown), the moving valve 33 of the ink discharge unit 30 is pushed upward. In this state, the valve mechanism 70 is in the state shown in FIG. 4, and the thick portion 76 </ b> C of the elastic valve 76 is displaced toward the blocking portion 90 side by the spring 86, and the ink supply space 84. And the through hole 76B is blocked. As a result, the ink M does not leak out.

  When printing is performed, negative pressure is applied to the ink ejection unit 30 from the inkjet printer side. This negative pressure is applied to the negative pressure forming space 82 via the ink outflow path 72, and the elastic valve 76 is elastically deformed toward the negative pressure forming space 82 against the force of the spring 86 by this negative pressure. As a result, since the ink supply space 84 and the through hole 76B are communicated with each other, the negative pressure on the negative pressure forming space 82 side is also applied to the ink supply space 84 through the through hole 76B. Due to the negative pressure, the ink M in the ink storage unit 10 is sucked into the ink supply space 84 via the ink suction port 74 and the ink suction path 78C, flows into the through hole 76B, and slits 88B and 88C of the displacement regulating unit 88. Then, it is supplied to the negative pressure forming space 82. The ink M is discharged from the ink outflow path 72 to the ink jet printer through the ink discharge unit 30.

  In this process, since the amount of ink M in the ink storage unit 10 decreases, the space S above the ink M also becomes negative pressure. When an air pressure difference more than necessary is generated between the inside and the outside, the air flow control unit 20 expands the valve body 22 by a slight elastic deformation, and thereby the micropores are expanded and air permeability is caused. Air flows from the higher side to the lower side to control the air flow rate. However, when the desired (rated) pressure difference does not occur, the amount of elastic deformation of the valve body 22 is small, so that air exchange is not performed. That is, the space S above the ink M is basically maintained at a negative pressure by the atmospheric pressure bias of the air flow rate control unit 20.

  When the printing by the ink jet printer is finished and the application of the negative pressure to the ink discharge unit 30 is stopped, the negative pressure in the negative pressure forming space 82 disappears, so that the elastic valve 76 is blocked by the biasing force of the spring 86 as shown in FIG. Displacement to the 90 side stops the supply of ink M. At this time, in addition to the amount of deformation of the elastic valve 76 being set to 2 mm by the displacement restricting portion 88, a negative pressure bias is acting on the inner space S side by the air flow rate control portion 20. Since the mechanism 70 is quickly closed, the leakage of the ink M is suppressed.

  As described above, according to the ink storage container 100 of the present embodiment, since the ink supply path is mechanically opened and closed by the valve mechanism 70, the ink when not used (when printing is not performed) in the state set in the ink jet printer. Can prevent leakage. In particular, in this valve mechanism 70, the displacement amount of the elastic valve 76 is limited to 5 mm or less, preferably 3 mm or less by the displacement restricting portion 88, so that the open / close response is improved. In particular, when shifting from the open state to the closed state, the elastic valve 76 and the blocking portion 90 are brought into contact with each other by movement of the displacement amount of about 4 mm or less, preferably 2 mm or less, so that the valve can be quickly closed. .

  Furthermore, since the thick part 76C of the valve mechanism 70 is fitted in the inner periphery of the spring 86, the stability of the thick part 76C during the opening / closing operation is increased, and the displacement of the thick part 76C is reduced. As a result, the contact state between the thick portion 76C and the blocking portion 90 and the contact state between the thick portion 76C and the displacement restricting portion 88 are improved, and the reliability of the product can be improved.

  Further, in order to quickly open the valve mechanism 70 when a negative pressure is applied to the ink discharge unit 30 from the ink jet printer side, it is preferable to make the force of the spring 86 as weak as possible. On the other hand, since the positive pressure is not positively applied from the ink jet printer to the valve mechanism 70 even after printing by the ink jet printer is completed, the elastic valve 76 of the valve mechanism 70 takes time (for example, about one hour). Close gradually while applying. In order to shorten this time as much as possible, it is preferable to increase the force of the spring 86. That is, in the valve mechanism 70, the quick opening and the quick closing are contradictory.

Therefore, in this embodiment, the contradiction is resolved by using the air flow rate control unit 20 and the valve mechanism 70 together and making the force of the spring 86 as weak as possible. For example, the spring 86 set in the valve mechanism 70 urges the elastic valve 76 with a weak force (here, 5 gf) of 3 gf (weight gram) to 20 gf (weight gram) when the elastic valve 76 is closed. The air flow rate control unit 20 maintains the internal pressure of the ink storage container 100 in a minute negative pressure state (−20 mmH ₂ O) as compared with the atmospheric pressure, and when the pressure difference more than that occurs, the air flow control unit 20 performs ventilation while taking time. Ensure sex. Accordingly, when a negative pressure is applied from the ink jet printer side to the ink discharge unit 30 during printing, the elastic valve 76 opens quickly because the biasing force of the spring 86 is relatively weak. During printing, negative pressure is continuously applied to the valve mechanism 70 and the amount of ink is reduced, so that the internal pressure of the ink storage container 100 further decreases. Due to this negative pressure, the valve body 22 of the air flow rate control unit 20 has air permeability and takes in air from the outside of the container. However, since this requires a certain amount of time, the internal pressure of the ink storage container 100 during printing is It continues to decrease and decreases to a negative pressure state of −200 mmH ₂ O, for example.

Even when printing by the ink jet printer is completed, the air flow rate control unit 20 generates a ventilation resistance, so that the internal pressure of the ink storage container 100 is maintained in the vicinity of −40 mmH ₂ O for a while (this is called a time difference action). . Accordingly, in addition to the restoring force of the spring 86, the negative pressure in the ink storage container 100 attempts to force the elastic valve 76 to return, so that the elastic valve 76 is quickly closed within, for example, 30 minutes. Even after the elastic valve 76 is closed, the internal pressure is maintained at −20 mmH ₂ O by the bias action of the air flow rate control unit 20, so that the elastic valve 76 opens unexpectedly even if environmental changes or vibrations occur. Can be prevented.

  As a result, the responsiveness of both the opening and closing operations can be further enhanced by the synergistic effect of the air flow rate control unit 20 and the valve mechanism 70.

  In addition, by using the air flow rate control unit 20 and the valve mechanism 70 in this manner, it is possible to suppress ink leakage even if one function is lost. For example, even if the elastic valve 76 does not close for some reason, the air flow rate control unit 20 can maintain the inside of the container at a negative pressure, so that ink does not easily leak. Similarly, even if the valve body 22 of the air flow rate control unit 20 is damaged and the inside of the ink storage container 100 is always at atmospheric pressure, the ink hardly leaks because the valve mechanism 70 exists.

  In addition, since the ink storage container 100 has a slit 88A (ink flow path) formed in the displacement regulating portion 88 of the valve structure 70, the through hole 76B is used while regulating the displacement amount of the elastic valve 76. Ink can be supplied smoothly. Further, since the inner diameter of the through hole 76B is set to 1 mm or less and the periphery thereof is surrounded by the thick portion 76C, the rigidity of the elastic valve 76 near the through hole 76C is partially increased, and the deformation amount is reduced. It is out. As a result, the contact accuracy when contacting the blocking portion 90 and the displacement restricting portion 88 is increased. Furthermore, since the inner diameter of the spring 86 is set to be equal to or larger than the diameter of the blocking protrusion 90A in the blocking portion 90, the spring 86 urges the elastic valve 76 to spread and block Adhesiveness with the protrusion 90A can be improved.

  In this embodiment, the ink M is supplied through the cylinder 34. However, the present invention is not limited to this, and for example, the ink M may be supplied from a part different from the cylinder 34. good.

  Although the present invention has been described in detail with reference to the embodiments, the specific configuration is not limited to these embodiments, and design changes and the like within the scope of the present invention are also included in the scope of the present invention. Is.

  The present invention can be used as an ink storage container, particularly an ink cartridge for an ink jet printer.

DESCRIPTION OF SYMBOLS 10 Ink storage part 11 Main body part 12 Upper surface part 13 Inside of ink storage part 20 Air flow control part 22 Valve body 24 Water-repellent film body 30 Ink ejection part 33 Moving valve 34 Cylinder 70 Valve mechanism 72 Ink outflow path 74 Ink suction port 76 Elastic valve 82 Negative pressure forming space 84 Ink supply space 86 Spring 88 Displacement restricting portion 90 Blocking portion 100 Ink storage container M ink

Claims (14)

A valve mechanism disposed in the ink storage container and disposed between the ink storage unit and the ink discharge unit;
An elastic valve configured to be elastically deformable and having a through-hole penetrating;
A negative pressure forming space that is disposed on the downstream side of the elastic valve and communicates with the ink ejection unit ;
An ink supply space that is disposed on the upstream side of the elastic valve and that communicates with the ink storage unit to supply ink to the elastic valve side;
A blocking portion disposed on the ink supply space side and in contact with the elastic valve to block between the ink supply space and the through hole;
A spring that is disposed on the negative pressure forming space side and biases the elastic valve toward the ink supply space to bring the blocking portion and the elastic valve into contact with each other;
A displacement restricting portion that is disposed on the negative pressure forming space side and contacts the vicinity of the through hole when the elastic valve is displaced downstream, and restricts the amount of displacement of the elastic valve ;
In the displacement restricting portion, a flow path is formed that communicates the through hole and the negative pressure forming space in a state in contact with the elastic valve.
Due to the negative pressure applied to the negative pressure forming space, the elastic valve is displaced downstream against the biasing of the spring, and the blocking portion and the elastic valve are separated from each other, and the ink supply space A valve mechanism characterized in that ink flows into the negative pressure forming space through a through hole. By the displacement restricting portion, the valve mechanism according to claim 1, characterized in that one end of the spring is held. The valve mechanism according to claim 2 , wherein the displacement restricting portion has a circular protrusion that fits inside the spring and holds one end of the spring. In a state where the elastic valve has contact with the blocking portion is biased to said spring, according to claim 1 to 3 gaps between the displacement restricting portion and the elastic valve is characterized in that it is set to 3mm or less The valve mechanism according to any one of the above. In a state where the elastic valve is the contact with the displacement restricting portion equivalent against said spring, of claims 1 to 4 gaps between the blocking portion and the elastic valve is characterized in that it is set to 2mm or less The valve mechanism according to any one of the above. The valve mechanism according to any one of claims 1 to 5 , wherein an inner diameter of the through hole is set to 1.5 mm or less. The valve mechanism according to any one of claims 1 to 6 , wherein the elastic valve is formed with an annular thick portion surrounding an outer periphery of the through hole. The valve mechanism according to claim 7 , wherein the thick portion is fitted inside the spring to hold the other end of the spring. The valve mechanism according to claim 7 or 8 , wherein a maximum outer diameter of the thick portion is set to 2 mm or more. The blocking portion is formed with an annular blocking protrusion that surrounds the vicinity of the outer periphery of the through hole of the elastic valve,
The inner diameter of the spring, the valve mechanism according to any of claims 1 to 9, characterized in that it is an outer diameter equal to or larger set of the blocking protrusion. The ink supply space, the valve mechanism according to any of claims 1 to 10, characterized in that it has an ink suction port located proximate while facing the bottom surface of the ink reservoir. A valve mechanism according to any one of claims 1 to 11 ,
An ink storage container, comprising: an air flow rate control unit that is provided above the ink storage unit and controls an air flow rate between the inside and the outside. The air flow rate control unit
Normally, air is not circulated, but an elastically deformable communicating porous valve body that exchanges air with the outside in accordance with a change in internal pressure of the ink storage unit;
The ink storage container according to claim 12 , further comprising: a liquid repellent film body that is disposed closer to the ink storage unit than the valve body and has air permeability and is subjected to a water repellent treatment. . The ink discharge section provided below the ink storage section is provided with a movement valve that moves up and down by urging from an external member, and the ink discharge and stop is switched by the movement of the movement valve up and down. the ink storage container according to claim 12 or 13, characterized in that there.

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