JP2010064429A - Inkjet recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a high image quality head which ensures positioning of a head to produce images with less irregularity and the like in a removable head of a so-called low profile structure having a reduced height. <P>SOLUTION: The aspect ratio of the length in the transverse direction of a contact pad to the length in the height direction thereof is twice or more of the aspect ratio of the length in the transverse direction of the head to the length in the height direction thereof. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ink jet recording head that performs recording by ejecting ink droplets from ejection ports and attaching them to a recording medium.

  As a typical method of an ink jet recording head and a recording apparatus, there is a method using an energy generating element, and droplets are ejected from minute ejection ports to perform recording on a recording medium. The energy generating element used to eject ink from the ink ejection port of the recording head uses an electromechanical transducer such as a piezo element, or heats a liquid by an electrothermal transducer element having a heating resistor. and so on.

  The ink jet recording head performs recording on a recording medium by ejecting ink based on an electric signal from the recording apparatus main body, and the head and the apparatus are electrically connected. As for the connection, there are a head and a main body that are directly connected by wiring or the like, and a head that can be detached from the main body, and an electrical connection is made almost simultaneously when the head is attached to the main body.

  The head that can be detached from the main body has an advantage that it can be easily replaced even when the head deteriorates over time or breaks down.

  The structure of such a head is as follows. An electric substrate on which contact pads for exchanging electrical signals are formed with respect to a support member (so-called chip tank) including an ink flow path, and an ink discharge port is formed connected to the electric substrate. The recording element substrate and the like. The chip tank has an engaging portion fixed to the main body.

The main body and the contact pad are connected via contact pins provided on the main body side, and the connection is ensured by pressing the contact pins. At the same time, the head receives a reaction force through the contact pad. An engagement reference between the chip tank and the main body is provided in the direction in which the reaction force acts, and the chip tank and the main body are engaged so that the reference is applied.
JP 2001-63053 A

  The demand for the ink jet recording main body includes high image quality and miniaturization, and along with this, the ink-jet head has been promoted to make the ink multi-color and miniaturize. As a means for downsizing while maintaining multi-colored ink, it is necessary to reduce the height in the vertical direction while maintaining the horizontal width in the inkjet head so-called low profile. .

  However, if an inkjet head with a horizontal aspect that is low in the width direction is positioned, the left and right weight balance tends to be unbalanced and it is easy to mount it at an angle. On the other hand, the abutting becomes insufficient, and it becomes difficult to mount with high accuracy.

  When printing is performed with the head attached to the carriage in an inclined state, ink does not land at a desired position, ruled line deviation occurs, print unevenness occurs, and the image is seriously affected.

  In view of such a situation, the present invention can reliably attach a low profile head to a main body with high accuracy, and achieve miniaturization and high-precision printing at the same time.

  Therefore, in an ink jet recording head that can be attached to and detached from the scanning carriage of the ink jet recording apparatus, the ink jet recording head has a support member including an ink flow path and an electric substrate, and a contact pad formed on the electric substrate, A plurality of electrical connections are made with the inkjet recording apparatus head via contact-type contact pins, and abutting against the positioning portion of the scanning carriage by the reaction force of the contact pressure by the contact pins, the electrical connection portion In the distance between the outermost contact points, the ratio of the horizontal distance to the vertical distance is at least twice the ratio of the horizontal width to the vertical height of the ink jet recording head.

  Accordingly, the aspect ratio of the area to which the contact load is applied becomes a horizontally long shape with respect to the aspect ratio of the head, so that the head is widely loaded. A closer position is urged with respect to the engaging portion including the reference position with respect to the carriage, and the reaction force from the contact pin can be reliably transmitted to the engaging portion and the reference position. Can be done

  Next, details of the present invention will be described in accordance with the description of the embodiments.

  Now, specific examples according to the present invention will be described.

  FIG. 1 is a view of an ink jet recording head as viewed from the contact wiring substrate side, FIG. 2 is a perspective view of the recording head, and FIG. 3 shows a schematic configuration of a printer using an ink jet recording method in which the recording head is removable.

  The recording head 100 includes a recording element substrate 1, a support substrate 2, a flow path forming member 3, a filter (not shown), a chip tank 4, and the like. The recording element substrate 1 is formed with a plurality of recording elements for discharging ink to the silicon substrate and electric wiring for supplying electric power to each recording element by a film forming technique, and a plurality of ink flows corresponding to the recording elements are formed. The passages and the plurality of discharge ports are formed by a photolithography technique to form a discharge nozzle row, and the ink supply ports for supplying ink to the plurality of discharge nozzle rows are formed to open in a plurality of rows on the back surface. The recording element substrate 1 is bonded and fixed to a support substrate 2, and a liquid chamber (not shown) for holding ink is constituted by the ink supply port and a space provided in the support substrate 2. Further, a plurality of recording element substrates 1 having a plurality of ejection nozzle arrays 1a are arranged, and a configuration is adopted in which a plurality of types of ink can be ejected.

  Further, the support substrate 2 holds the flexible wiring substrate 5 so that the flexible wiring substrate 5 and the recording element substrate 1 are electrically connected. The flexible wiring board 5 is connected to the contact wiring board 6 and constitutes an electric wiring portion 13. The contact wiring board 6 has an external signal input terminal (hereinafter referred to as contact pad) 6 a for receiving an electric signal from the main body, and the contact wiring board 6 is positioned and fixed on the back side of the chip tank 4. In addition, an electrical signal for ejecting ink is input from the recording apparatus main body to the recording element substrate 1 through the electrical wiring portion.

  The contact wiring board 6 has 58 contact pads 6a arranged in four rows in a staggered arrangement. The contact pads 6a have a width of 1.6 mm and a length of 2.6 mm for the contact pads arranged in the lowest vertical row, and the contact pads of the other rows have a width of 1.6 mm and a length of 2. mm. 2 mm. The distance between the contact pads is 0.8 mm in the horizontal direction and 0.4 mm in the vertical direction. The distance between the centers of the contact pads located at the outermost positions in the horizontal direction is 34.8 mm, and the distance between the centers of the uppermost and lowermost contact pads in the vertical direction is 7.8 mm. The ratio of the horizontal distance Wc to the vertical distance Hc at the center of the contact pad is about 4.5 times.

  On the recording element substrate 1, nozzle rows for ejecting ink are formed, and a large number of electrothermal conversion elements (hereinafter referred to as heaters) are provided.

  A flow path forming member 3 is welded to the chip tank 4 to form an ink flow path (not shown) from the ink tank to the support substrate 2.

  Further, a chip tank unit 101 composed of a chip tank 4, a flow path forming member 3, a filter (not shown), etc., and a recording element unit 102 composed of a recording element substrate, a support substrate, and an electric wiring portion are coupled with screws. Thus, the recording head 100 is configured. The chip tank 4 has a horizontal width Wh of 93.7 mm and a vertical height Hh of 44 mm. The ratio of the horizontal width Wh to the vertical height Hh of the chip tank is about 2.1 times.

  The carriage 103 engages with the recording head 100 and engages with a carriage cover for guiding the recording head 100 to the mounting position of the carriage 103 and a chip tank of the recording head, and presses the recording head to be set at a predetermined mounting position. A headset lever 104 is provided. In other words, the head set lever is provided so as to be rotatable with respect to the upper shaft of the carriage, and a head set plate (not shown) is provided via a spring at the engaging portion with the print head 100, and the print head 100 is driven by this spring force. Is configured to be mounted on the carriage 103 while pressing.

  FIG. 4 is a schematic diagram for explaining a process in which the ink jet recording head according to the embodiment of the present invention is mounted on the carriage of the recording apparatus main body. The contact pins 10 of the recording apparatus main body are provided on the connector base 11 and can be displaced in the pushing direction. The contact pin 10 of this embodiment protrudes 1.5 mm from the connector base 11, and the push-in amount from 0.1 mm to 1.1 mm is the contact guarantee area. The carriage 103 has a guide rail 12 for guiding the guide shaft 13.

  As shown in FIGS. 4A to 4C, the ink jet recording head 100 is mounted on the carriage 103 while the guide shaft 13 is guided to the guide rail 12 and draws a rotation locus. As shown in FIG. 4 (b), the contact pin 10 contacts the contact pin 10 from the contact pad 6a closer to the guide shaft 13, and the contact pin 10 drags the contact pad 6a. Connect. In the state where the electrical connection is completed as shown in FIG. 4 (c), the contact pin 10 is pushed in by about 0.5 mm, and the reaction force of the contact pin at this time is about 40 g per pin, which is 2400 gf as a whole. The reaction force of

  The reaction force from the contact pin 10 applies a load to the chip tank 4 and causes the chip tank 4 to be deformed. Therefore, the reaction force and the load position from the connector base 11 are set so that the deformation of the chip tank is within the contact guarantee area of the contact pin 10 while the head is attached.

  There are two engagement portions between the carriage and the head as the reference position vertically below, and two engagement portions with the head set lever 104 at the outermost portion in the horizontal direction above the head vertical. When mounted on the carriage 103, since the vertical height is small, the rotation angle from the start of contact with the headset lever 104 to the fixing becomes large. At this time, the reaction force from the contact pin 10 gradually increases in the direction of pushing to the reference position. The weighted position due to the reaction force occurs in a horizontal direction (left and right) because the vertical and horizontal aspect ratio of the weighted portion to the contact pad 6a is about twice the vertical and horizontal aspect ratio of the chip tank. Thereby, the abutting to the reference position is performed substantially uniformly on both the left and right sides. Further, since the reaction force spreads in the horizontal direction (left and right), even if the attachment is performed at an incline, contact with the connector is started at an early stage of attachment. Therefore, the larger the push-in, the greater the reaction force from the connector, and the smaller the push-in, the smaller the reaction force. When it is finally fixed to the carriage, the tilt is corrected and fixed in the normal state. Is done.

  As described above, according to the present invention, an ink jet recording head, particularly a low profile head, can be attached to a carriage reliably and with high accuracy without increasing the number of components. As a result, it is possible to achieve downsizing and high accuracy without affecting the print quality and the like.

Recording head viewed from the contact pad surface Perspective view of recording head Schematic configuration of printer using ink jet recording system Explanatory diagram of the process of mounting the recording head on the carriage

Explanation of symbols

2a / 2b Reference engagement part 4 Chip tank 4a / 4b Engagement part

Claims (5)

In a detachable inkjet recording head with respect to the scanning carriage of the inkjet recording apparatus,
The ink jet recording head has a support member including an ink flow path and an electric substrate. A contact pad formed on the electric substrate is electrically connected to the ink jet recording apparatus head via a contact type contact pin. And is abutted against the positioning part of the scanning carriage by the reaction force of the contact pressure by the contact pin,
In the distance between the outermost contact points of the electrical connection portion, the ratio of the horizontal distance to the vertical distance is more than twice the ratio of the horizontal width to the vertical height of the ink jet recording head. Inkjet recording head.   2. The ink jet recording head according to claim 1, wherein a plurality of engaging portions with the scanning carriage are arranged near the outside.   2. The ink jet recording head according to claim 1, wherein an engaging portion serving as a reference with the scanning carriage is disposed at a lower portion in the vertical direction.   2. The ink jet recording head according to claim 1, wherein the centers of gravity of the plurality of electrical contacts are substantially the same as the horizontal center of the ink jet recording head.   2. The ink jet recording head according to claim 1, wherein the supporting member is made of a material that is elastically deformed.

Images