Liquid ejection apparatus, liquid container, and manufacturing method thereof

There are provided a liquid ejection apparatus with low costs, a liquid container, and a manufacturing method thereof. To this end, a rocking body is assembled to the liquid container to suppress the drop thereof by melting and swaging of a support shaft.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a liquid ejection apparatus capable of containing liquid and including a detection unit configured to detect a remaining amount of the liquid, and to a liquid container.

Description of the Related Art

A liquid ejection apparatus includes a supply system that supplies liquid such as ink to a liquid ejection head. In the upstream of the supply system, a liquid container that holds the liquid is detachably attached. Some liquid ejection apparatus includes a detection unit configured to detect a remaining amount of liquid in the liquid container. In the case where the remaining amount of the liquid in the liquid container mounted in the liquid ejection apparatus is small, the fact is detected and the liquid container is exchanged to a new one, thereby allowing continuous use of the liquid ejection apparatus.

Japanese Patent Laid-Open No. 2012-000861 discloses a liquid container that includes a rocking member (rocking body) that rocks around a support shaft depending on a remaining amount of liquid in the liquid container and detects the remaining amount of the liquid, based on a position of the rocking body.

SUMMARY OF THE INVENTION

The present invention is a liquid ejection apparatus that ejects liquid contained in a liquid container and can mount the liquid container capable of containing liquid and having a rocking body rotatable around a support shaft depending on an amount of contained liquid, wherein the rocking body is assembled to the liquid container by melting of a part of the support shaft.

DESCRIPTION OF THE EMBODIMENTS

In order to reliably catch the change in liquid surface in a liquid container and detect the change in remaining amount of the liquid, it is necessary to support a rocking body without disturbing the motion of the rocking body. With a configuration disclosed in Japanese Patent Laid-Open No. 2012-000861, after a support shaft is passed through a shaft hole of the rocking body, a cap member is fit onto the support shaft, thereby suppressing the drop of the rocking body without disturbing the operation of the rocking body.

First Embodiment

However, with the configuration disclosed in Japanese Patent Laid-Open No. 2012-000861, the cap member is required to suppress the drop of the rocking body and there is a problem of an increase in costs due to an increase in the number of parts.

Therefore, according to the present invention, there are provided a liquid ejection apparatus with low costs, a liquid container, and a manufacturing method thereof.

Hereinbelow, a description will be given of a first embodiment of the present invention with reference to the drawings.

FIG. 1is a schematic diagram showing a main portion of a liquid ejection apparatus to which the present embodiment can be applied. The liquid ejection apparatus includes: an ejection head40that ejects liquid; a plurality of detachable liquid containers1that is connected to the ejection head40; and a control unit50that controls the ejection of the liquid from the ejection head40. Further, the control unit50includes a liquid remaining-amount detection unit51that can detect a remaining amount of liquid in the liquid container1based on information from a sensor52provided in a container mounting unit55to which the liquid container1is mounted.

The ejection head40is connected to the liquid container1with a soft tubular member. The ejection head40ejects liquid supplied from the liquid container1based on information from the control unit50. The sensor52includes a light reception unit53and a light emission unit54. The light reception unit53receives light emitted by the light emission unit54and sends a signal to the liquid remaining-amount detection unit51.

FIG. 2is a perspective view showing the liquid container1mountable in the liquid ejection apparatus.FIG. 3is an exploded perspective view of the liquid container1. The liquid container1has a rectangular-parallelepiped outer shape in which a length in a width direction (arrow y direction) is small and each of a length in a height direction (arrow z direction) and a length of a depth direction (arrow x direction) is longer than the length in the width direction. The width direction, the height direction, and the depth direction are perpendicular to each other, and a main body frame7is formed along the directions.

In the liquid container1, a part of a portion storing liquid is formed of a flexible film. The main body frame7includes a side surface9that is widened in a depth direction and a height direction. Another side surface facing the side surface9is covered with a film, thereby forming a liquid storage chamber4that can store (contain) the liquid inside the main body frame7. Further, the liquid container1includes a remaining-amount detection chamber3that is formed by communication with the liquid storage chamber4and by projection of the main body frame7and a supply port2that can supply the liquid in the liquid storage chamber4to the outside of the liquid container1.

The liquid container1includes a support shaft5and a support post8that are vertically provided with respect to the side surface9, and further includes a rocking body11that rotates (rotatable) around the support shaft5. The rocking body11includes a float unit12and a detection unit13. In the case of rotating the rocking body11, the movement of the float unit12is regulated (limited) with the support post8. Further, it is so configured that by rotation of the rocking body11, the detection unit13moves in the remaining-amount detection chamber3, corresponding to the position of the float unit12. In the case where there is sufficient liquid in the liquid storage chamber4, the float unit12rises with buoyant force of the liquid and is located above in the height direction (arrow z direction).

In this case, the detection unit13is configured to be located at the lowest position of the remaining-amount detection chamber3, between the light reception unit53and the light emission unit54of the sensor52. That is, in the case where there is sufficient liquid in the liquid storage chamber4, light of the sensor52is blocked with the detection unit13, and the liquid remaining-amount detection unit51does not receive a signal from the sensor52. In the case of consuming the liquid in the liquid storage chamber4, the liquid surface of the liquid in the liquid storage chamber4gradually lowers, and the position of the float unit12thus gradually lowers, and the position of the detection unit13gradually rises.

In the case where the remaining amount of the liquid in the liquid storage chamber4is extremely small, the float unit12is located at the lowest position and the detection unit13is located at the highest position and reaches a position where the light from the sensor52is not blocked. At this time, the liquid remaining-amount detection unit51receives a signal from the sensor52, there is not the liquid in the liquid container1and the liquid remaining-amount detection unit51recognizes an exchange timing. As mentioned above, it is so configured that ON/OFF operation of the sensor52is performed depending on the position of the detection unit13, and the remaining amount of the liquid in the liquid container1is detected (detectable).

Note that, according to the present embodiment, the description is given of the example of using an optical sensor as the sensor52. However, the present invention is not limited to this, and may use another system (e.g., magnetic sensor). In the case of the magnetic sensor, the detection unit13needs to include a magnetic body.

As mentioned above, the rocking body11rocks in accordance with the change in the remaining amount of liquid in the liquid storage chamber4, and it is necessary to allow rocking of the rocking body11and suppress the drop thereof in a state in which the support shaft5is passed through a support shaft through-hole of the rocking body11. According to the present embodiment, the following method realizes a configuration in which the rocking body11can rock and does not drop.

FIG. 4is a cross-sectional view showing a state in which the support shaft5and the rocking body11are combined. According to the present embodiment, in the case of assembling the rocking body11, the support shaft5is passed through the through-hole provided in the rocking body11. Thereafter, the tip end portion of the support shaft5having passed through the through-hole is swaged and a stop portion6is formed with an area wider than an opening area of the through-hole, thereby suppressing the drop of the rocking body11. That is, the rocking body11is assembled to the liquid container by melting of the tip end portion as a part of the support shaft5. Swaging by the melting of the tip end portion of the support shaft5is performed by use of a method for heating a metallic block21by using a constant heater or an impulse heater and pressing the metallic block21to the tip end portion of the support shaft5or a method for generating friction heat due to an ultrasonic welding machine or a twist oscillation welding machine at the tip end portion of the support shaft5.

As a state after the swaging, clearance is provided to some degree among the main body frame7, the stop portion6, and the rocking body11, and thus the motion of the rocking body11is required not to be disturbed as much as possible. To this end, the swaging is performed so that a length dimension L of the support shaft5is longer than a thickness dimension H of the rocking body11. As such a swaging method that the motion of the rocking body11is unlikely to be disturbed, there is a method for controlling a swaging amount. The control of the swaging amount includes control of reach height of a welding tool for descending a welding tool such as the metallic block21to a constant height from a reference position for fixing the main body frame7in the height direction and control of a displacement amount for detecting the tip end position of the support shaft5and descending the welding tool by a constant amount with a detection position as a reference. Further, such swaging control is possible that the clearance is provided among the main body frame, the swaging portion, and the rocking body by keeping a given amount of energy to be constant with the tip end position of the support shaft5as a reference.

As mentioned above, with melting and swaging of the support shaft, the rocking body is assembled to the liquid container, thereby suppressing the drop thereof. Thus, the liquid container can be manufactured with low costs.

Note that, it is preferable that the length of the support shaft5is longer and the height of the stop portion6after the swaging is higher than that of a frame portion of the liquid container1and, in the case of welding the film for sealing the liquid storage chamber4, the end of the support shaft is simultaneously welded to the film. Thus, it is possible to suppress the flattering and the deflection of the film.

Further, in the case where the sealing member is a member harder than the film such as a resin plate, the length of the stop portion6is lower than the height of the frame portion, and thereby it can be configured such that the assembling of the resin plate or the like is unlikely to be disturbed.

Second Embodiment

Hereinbelow, a description is given of a second embodiment of the present invention with reference to the drawings. Note that, since the basic configuration of the present embodiment is similar to that of the first embodiment, only a characteristic configuration is described in the present embodiment hereinbelow.

FIG. 5is a cross-sectional view showing a state in which the support shaft5and the rocking body11are combined in the present embodiment. In the present embodiment, in the case of assembling the rocking body11, the support shaft5is passed through a through-hole provided in the rocking body11. Thereafter, the support shaft5is passed through a hole of a spacer15with a predetermined width, and a tip end portion of the support shaft5is swaged, thereby forming a stop portion6with an area wider than that of the through-hole. After the formation of the stop portion6, the spacer15is removed. The above-formed stop portion6suppresses the drop thereof so as not to disturb the operation of the rocking body11.

In the present embodiment, in the case of swaging with a swaging tool such as a metallic block, a position where the formed stop portion6reaches the spacer is a reference of the end, and the swaging is possible in a state in which influence of tolerance of parts such as thickness of a main body frame, the length of the support shaft, and thickness of the rocking body is unlikely to receive. A material such as metal is used for the spacer15so as not to be melted with the support shaft5or the rocking body11. Here, the material of the spacer is not limited to metal and resin or the like may be used which has been subjected to surface treatment so as not to be welded.

FIGS. 6A to 6Dare diagrams showing the spacer15. As shown inFIG. 6A, the spacer15is divided into two parts. The parts are set to cover the circumference of the support shaft5as shown inFIG. 6Band swaging is performed. After completion of the swaging as shown inFIG. 6C, the spacer15is detached as shown inFIG. 6D. Here, the division of the spacer15is not limited to the two-division, and may be plural-division.

The spacer15can be inserted between the main body frame7and the rocking body11. In the case where the side of a swaging surface of the rocking body11is an end reference, the rocking body11is also melted in swaging the support shaft5. In this case, the materials of the support shaft5and the rocking body11are combination of materials having a melting point of the support shaft5lower than that of the rocking body11, thereby suppressing the welding of the rocking body11. For example, in the case where the material of the main body frame7to which the support shaft5is formed is a polyethylene (PE) material and the material of the rocking body11is polypropylene (PP) material, the melting point of the PE material is lower than that of the PP material, and therefore it is possible to melt and swage only the support shaft5without melting the rocking body11.

Other Embodiments

FIGS. 7, 8A, and 8Bare diagrams showing other embodiments of the present invention. In the above described embodiments, the description is given of a form of forming the liquid storage chamber4by forming the one side of the main body frame7by molding and by attaching the film or the like to the other side. However, the present invention is not limited to this. As shown inFIG. 7, the present invention can be applied to a main body frame in a form of forming both the sides with a film or the like without forming a wall surface by molding except for the circumference of the support shaft5.

Further, a relationship between the support shaft of the main body frame and the support shaft through-hole of the rocking body can be embodied also in a configuration in which the support shaft is provided in the rocking body and the support shaft through-hole is formed in the main body frame as shown inFIG. 8B. In this case, preferably, the support shaft formed in the rocking body is swaged from an outer surface of the main body frame and a swaging portion is covered with a film or the like, thereby suppressing the leakage of the liquid.

This application claims the benefit of Japanese Patent Application No. 2015-224951 filed Nov. 17, 2015, which is hereby incorporated by reference wherein in its entirety.