Incremental printing of symbolic information – Ink jet – Ejector mechanism
Reexamination Certificate
1999-01-26
2001-07-17
Le, N. (Department: 2861)
Incremental printing of symbolic information
Ink jet
Ejector mechanism
C347S029000
Reexamination Certificate
active
06260943
ABSTRACT:
This application is based on Patent Application No. 19507/1998 filed on Jan. 30, 1998 in Japan, the content of which is incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an ink-jet printing apparatus, more particularly to an ink-jet printing apparatus performing the printing by ejecting an ink from a printing head toward a printing medium.
2. Description of the Related Art
Conventionally, in an ink-jet printing apparatus performing the printing by ejecting an ink from an ink ejection opening of a printing head toward a printing medium, means for protecting the ejection opening and the ejection recovery processing means are provided for solving the problems of plugging of the ink ejecting opening portion of the printing head due to the drying or ejection failure of the ink due to the dart, the bubble or the like within the ink ejection opening.
Here, throughout the disclosure, the words “ejection recovery” represents not only for resolving of the problem of the ejection failure but also, in the broader sense, for maintaining appropriately the ejection performance of the ink in the ink ejection opening of the printing head.
Major construction of such ink ejection protecting means is a cap formed with an elastic material, such as rubber or the like. The cap covers an ejection opening forming surface formed on the printing head (hereinafter occasionally referred to simply as “head”). Major construction and function of the ejection recovery processing means is to suck air within the cap by a vacuum generating means, such as a pump or the like to reduce the pressure therein for causing the forced discharge of the ink through the ejection opening and whereby to resolve the problem of the ejection failure of the ink.
Furthermore, another ejection recovery means is a preparatory ejection process for ejecting the ink from the head for a predetermined times for elimination of cause of the ejection failure. In this preparatory ejection process, it is typical to use the cap as a receptacle for ejected ink. The reason is that, by using the existing cap as the receptacle, it becomes unnecessary to provide special ink receptacle means to permit down-sizing by space saving or cost-down.
Furthermore, as a mechanism for moving the cap between an open condition (a condition moved away from the ejection opening forming surface of the head) and a closed condition (a condition where the head and the ejection opening forming surface are in contact), it is typical to pivot the cap about a cap supporting member or a pivot center. Advantage of employment of the method set forth above is that the down-sizing is possible and the high precise control of the relative position between the ejection opening forming surface of the head and the cap can be easily performed.
Furthermore, when the relatively high precision is required in the positional relationship between the cap and the head in order to certainly cover the ejection opening forming surface of the head with the cap and certainly maintaining sealing ability with the ejection opening forming surface, it is possible to provide a relative positioning means respectively for a head unit (including a carriage and so on) and a cap unit (including the cap supporting member and so on). As one example, the relative positioning of the cap and the head can be certainly performed by providing a positioning boss in the cap supporting member and a positioning hole, in which the positioning boss is inserted, in the carriage.
However, when the conventional method is used, in order to place the cap in an open condition, namely in a condition where the cap unit is placed away from the head unit, a necessary magnitude of pivoting of the cap supporting member inherently becomes large. Particularly, when a projection, such as a boss-shaped projection or the like is provided as the positioning means, this tendency becomes significant to hinder the down-sizing of the printing apparatus.
Another reason is that the accurate positioning is difficult unless the posture of the cap upon the positioning is in a parallel position to the posture of the cap in the capping position.
SUMMARY OF THE INVENTION
In order to solve such problems in the prior art, it is an object of the present invention to provide an ink-jet printing apparatus which can accurately position a head unit and a cap unit at a desired posture upon the opening and closing of the cap.
It is another object of the present invention to provide an ink-jet printing apparatus comprising a cap for covering a surface in which the ink ejection openings of an ink-jet printing head is formed, a cap supporting member pivoted with holding of the cap for opening or closing the ink-jet printing head, and posture control means for controlling posture of the cap for placing the cap in parallel to the surface at least at first and second positions between opening state and closing state of the cap.
Also, an ink-jet printing apparatus of the present invention is characterized in that the first position is a position at a cap opening state and a second position is a position at initiating state of positioning for the cap with respect to the surface for performing the cap closing.
Furthermore, an ink-jet printing apparatus of the present invention is characterized in that the posture control means includes rocking means provided on the cap supporting member for rocking the cap, rotational moment applying means for applying a rotational moment to the cap for rocking motion of the cap about a rocking center of the rocking means, a first stopper for stopping the cap at the first position with respect to the ink-jet printing head by restricting rocking motion by the rotational moment in the cap opening during the cap is substantially in the cap opening state, and a second stopper for stopping the cap at the second position by restricting rocking motion by the rotational moment in the cap closing state during the cap is substantially in the cap closing state.
Stillmore, an ink-jet printing apparatus of the present invention is characterized in that further comprises positioning means for performing relative positioning of the cap and the ink-jet printing head.
An ink-jet printing apparatus of the present invention is characterized in that the relative positioning means has projecting member on one of the capping unit or the head unit and a hole portion, in which the projecting member is inserted, on the other of the capping unit or the head unit.
Also, an ink-jet printing apparatus of the present invention is characterized in that the rotational moment by the rotational moment applying means is applied by a spring.
Furthermore, an ink-jet printing apparatus of the present invention is characterized in that further comprises means as ejection recovery means for the ink-jet printing head, for performing preparatory ejection by the ink-jet printing head at the first position, in which the preparatory ejected ink is received within the cap.
Stillmore, an ink-jet printing apparatus of the present invention is characterized in that the ejection recovery means has means for discharging ink from the ejection opening by acting a suction force via the cap.
An ink-jet printing apparatus of the present invention is characterized in that the ink-jet printing head has an electrothermal transducer generating a thermal energy in response to application of an electric power to be used for ink ejection.
Also, an ink-jet printing apparatus of the present invention is characterized in that the ink-jet printing head performs ejection of an ink toward a printing medium through the ejection openings, utilizing film boiling caused in the ink by thermal energy to be applied by the electromagnetic transducer.
As set forth above, in the present invention, the ink-jet printing apparatus can restrict necessary pivoting magnitude of the cap supporting member upon opening and closing the cap, to be minimum by the above construction. Also, it is possible to take a construction in which the
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
Le N.
Nguyen Lamson D.
LandOfFree
Ink-jet printing apparatus with multi-position cap does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ink-jet printing apparatus with multi-position cap, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink-jet printing apparatus with multi-position cap will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2503407