JP2670209B2 - Inkjet printer drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device for an ink jet printer.

[0002]

2. Description of the Related Art Conventionally, JP-A-3-10843, JP-A-3-55253, JP-A-3-65347, JP-A-3-101944, and JP-A-2-151.
445, JP-A-2-178050, JP-A-2-17851, JP-A-2-188246, JP-A-1-125238, JP-A-62-23
As described in Japanese Patent Publication No. 4942, an ink cartridge in which an ink tank and an inkjet head are unitized is mounted on a reciprocating carriage, and ink is ejected from nozzles of the inkjet head in the process of moving the carriage. There are inkjet printers that print by doing so.

[0005] Here, the ink cartridge and the carriage require connecting means for inputting a print signal to the ink jet head. There is a connection method in which a pin terminal is provided on the ink cartridge, a commercially available connector is provided on the carriage, and the pin terminal on the ink cartridge is connected to the connector of the carriage when the ink cartridge is mounted on the carriage. The structure for moving the connector relative to the pin terminal for mounting is complicated.

For this reason, there is one shown in FIG. This will be described below with reference to FIG. 61 is a rubber pad, and this rubber pad 61 is held by a carriage (not shown) provided to be able to reciprocate. A large number of protrusions 62 are formed on the surface of the rubber pad 61. Reference numeral 63 denotes a vinyl chloride-based flexible cable opposed to the rubber pad 61 and held by the carriage. The flexible cable 63 has a large number of connecting portions 64 swelling to the surface side opposed to the protrusions 62 made of thin-film metal. Has been formed. These connecting portions 64 are flexible cables 6
It is connected to a drive unit (not shown) by a connection line 65 formed on the No. 3. A connection pattern 66 is formed of a metal foil on one surface of an inkjet head (not shown) of an ink cartridge that is detachably held by the carriage. The connection pattern 66 has a large number of terminals 67 that come into contact with the connection portion 64. These terminals 67 are connected to heating elements provided inside each nozzle of the inkjet head.

Therefore, when the ink cartridge is mounted on the carriage, the connection portion 64 connected to the driving portion is connected to the terminal 67 of the ink jet head.
Here, since the protruding height of the connecting portion 64 is not uniform and the contact with the terminal 67 is incomplete, the connecting portion 64 is pressed against the terminal 67 by the protrusion 62 of the rubber pad 61. At the time of printing, a voltage is applied to the selected terminal 67, and this terminal 67
A heating element connected to the nozzle heats the ink in the nozzle to boil, and the pressure increased by the boiling causes the ink to fly from the nozzle. Ink is supplied to each nozzle from an ink tank (not shown).

[0006]

Since the protrusion 62 of the rubber pad 61 has a small amount of bending, it is difficult to securely press the entire connecting portion 64 against the terminal 67 if there is a variation in the mounting position of the ink jet head with respect to the carriage. Is. Further, since the rubber pad 61 is required, the number of parts is increased and the cost is increased.

[0007]

According to a first aspect of the present invention, an ink jet head having an ink tank having a carriage reciprocally movable, a large number of ink ejection means for individually ejecting ink from nozzles, and an ink tank are provided. An ink cartridge which is coupled to the carriage and is detachably mounted on the carriage, a wiring board provided on the ink cartridge having a large number of input contacts, and at least the metal plate having elasticity. A part of a large number of connection pieces elastically contacted with the contacts is fixed to an insulating material, and is constituted by a connector attached to the carriage.

According to a second aspect of the present invention, in the first aspect, a large number of connecting pieces contacting the contacts of the ink cartridge are included.
The carriage is provided with a connector having a grounding connecting piece defined in a shape to be brought into contact with the grounding surface of the ink cartridge before these connecting pieces come into contact with the contact.

According to a third aspect of the present invention, in the first aspect, the carriage is provided with an insulator having a plurality of grooves into which the connection pieces are inserted.

According to a fourth aspect of the present invention, in the first aspect, the bottom surface which is in contact with the free ends of the connecting pieces and determines the return position of the connecting pieces is formed in the groove of the insulator.

According to a fifth aspect of the present invention, in the second, third or fourth aspect, a contact portion protruding toward the ground plane side of the ink cartridge is formed on a part of the grounding connecting piece, and the ink cartridge is formed on the other connecting piece. A contact portion protruding from the contact side of the groove is formed, and the depth of the bottom surface of the groove into which the grounding connection piece is inserted is made smaller than the depth of the bottom surface of the groove into which the other connection piece is inserted.

[0012]

According to the first aspect of the present invention, when the ink cartridge is mounted on the carriage, each contact of the ink cartridge is connected to the drive portion through the connecting piece on the carriage side, but the connecting piece has an elastic metal plate. By making it possible to increase the bending amount of the connecting piece, it is possible to reliably bring the connecting piece into contact with the ink cartridge side contact or the like even if an error occurs in the mounting dimension of the ink cartridge with respect to the carriage. Moreover, the number of parts can be reduced and the cost can be reduced.

According to the second aspect of the present invention, even when the ink cartridge is mounted on the carriage while the signal from the drive unit is applied to the connecting piece of the connector, the connecting piece for grounding is connected to the ink cartridge side. Another contact piece can be brought into contact with the contact point on the ink cartridge side after the contact with the ground surface, whereby the circuit element on the ink cartridge side can be prevented from being destroyed.

According to the third aspect of the invention, by inserting each connecting piece into the groove formed in the insulator, it is possible to maintain the insulating state between the connecting pieces.

According to the fourth aspect of the present invention, the pressure contact force of each connecting piece with respect to the ink cartridge can be increased by bringing the free ends of the elastically bending connecting pieces into contact with the bottom surface of the groove. .

According to the fifth aspect of the present invention, the contact portion of the grounding connecting piece is provided on the ink cartridge side by making the depth of the bottom surface of the groove with which the free end of each connecting piece abuts. By projecting to the ground plane side, the contact part of the other connecting piece can be kept in a state of being retracted from the contact part of the connecting piece for grounding. Therefore, the signal from the drive part is applied to the connecting piece of the connector. In this state, even if the ink cartridge is mounted on the carriage, it is possible to bring another connection piece into contact with the contact on the ink cartridge side after the connection piece for grounding comes into contact with the grounding surface on the ink cartridge side, As a result, it is possible to prevent the destruction of the circuit element on the ink cartridge side.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. First, FIGS. 5, 8, and 9 show the structure of the ink cartridge 1. FIG. This ink cartridge 1 is
It is formed by combining an ink tank 3 having a cap 2 on one side to store ink, a metal head substrate 4, and a cartridge cover 5. A recess 6 is formed on the surface of the ink tank 3 opposite to the cap 2, and openings 7, 8 and 9 are formed on the bottom surface, the top surface and the front surface of the recess 6, respectively. The head substrate 4 is fixed to a boss 11 protruding from a wall surface 10 of the recess 6. The flat head substrate 4 has flat surfaces 12 and 13 parallel to each other, a circular positioning hole 14, and an oval positioning hole 15. An ink jet head, which will be described later, is formed on the flat surface 13 of the head substrate 4, and the periphery of the nozzle on the front surface of the ink jet head is covered with a face plate 16. Further, the cartridge cover 5 has three openings 17 that open a part of the head substrate 4.

As shown in FIG. 6, an ink jet head 18 is provided on the inner flat surface 13 of the head substrate 4.
A wiring board 20 having a large number of contacts 19 is provided. A connector 24 is provided in which a large number of connection pieces 21 and one connection piece 22 are embedded in an insulating material 23. The connection piece 21 is projected in the shape of a letter "C" and the contact 1
9 has a contact portion 21a which resiliently contacts, and the connecting piece 22 has a contact portion 22a which protrudes in a U-shape and which resiliently contacts the metal surface of the head substrate 4. As shown in FIG. 4, the rear ends of the connection pieces 21 and 22 are the substrate 23a.
The substrate 23a is fixed to a second carriage frame 32 which will be described later.

As shown in FIG. 7, in the ink jet head 18, a silicon substrate 26 having a plurality of heating elements 27, which are ink ejecting means, is joined in front of the inner flat surface 13 of the head substrate 4. Then, the silicon substrate 29 on which the ink reservoir 28 is formed by a large number of grooves for locating the heating element 27 is bonded onto the silicon substrate 26. The opening surface at the tip of each of the ink reservoirs 28 is a nozzle 25 facing the print medium. Further, a matrix circuit (not shown) for driving the heating element 27 is formed on the silicon substrate 26.

Next, the carriage 30 is shown in FIGS.
The structure of is shown. First, as shown in FIG.
Reference numeral 0 indicates a first carriage frame 31 and a second carriage frame 32 which are made of insulating resin.
And are slidably fitted along a carrier shaft (not shown). That is, the first carriage frame 31 has a support wall 33 facing the flat surface 12 outside the head substrate 4, and the support wall 33.
And a cylindrical portion 34 which is continuous from the inner surface of and is slidably fitted to the carrier shaft. The ink cartridge 1 is attached to the second carriage frame 32.
A column-shaped cartridge holding portion 35 which is a pressurizing means that presses the flat surface 13 of the head substrate 4 through the opening 7 through the opening 7 and a protruding portion 36 along the upper surface of the cylindrical portion 34. An inverted U-shaped wall portion 37 formed at the tip of the protruding portion 36 is formed. The cartridge holder 35 is held by one end of a leaf spring 38 and presses the head substrate 4 resiliently.
Having. On the inner surface of the wall 37, a spiral cam 40 is formed integrally with a straight line passing through the center of the wall 37 along the longitudinal direction of the protrusion 36 as an axis.

As shown in FIG. 2, the support wall 33 of the first carriage frame 31 is formed with a modified hole 41 for projecting the projecting portion 36 and the wall portion 37. On both sides of 41, grooves 43 are formed to slidably hold ribs 42 formed on both sides of the protrusion 36. Further, the second carriage frame 32 has a U-shaped claw 45 slidably holding ribs 44 formed on both sides of the cylindrical portion 34 of the first carriage frame 31, A protruding shaft 46 is formed, and a spring 47 for pressing the support wall 33 is fitted to the shaft 46.

Further, as shown in FIG. 3, the flat surface 12 of the first carriage frame 31 opposite to the contact 19 of the head substrate 4 is brought into contact with the inner surface of the support wall 33. One projection 48 and two positioning portions 49 fitted into the positioning holes 14 or 15 formed in the head substrate 4 are formed so as to protrude. The tip surface of the protrusion 48 is located in a predetermined plane substantially orthogonal to the above-mentioned carrier shaft.

Next, the second carriage frame 32
FIG. 11 shows a vertical front view of a part of the cartridge holding portion 35 of FIG. The contact portion 22a of the connection piece 22 for grounding is bent into a shape positioned on the head substrate 4 side and above the contact portion 21a of the other connection piece 21. Further, the cartridge holding portion 35 as an insulator is provided with the connector 24.
The connection pieces 2 that hold the upper portions of the connection pieces 21 and 22 of the
A large number of grooves 5 for insulating between 1 and between the connection pieces 21 and 22.
0 is formed. The depth of the bottom surface of the groove 50 holding the connection piece 21 is set to be deeper than the depth of the bottom surface of the groove 50 holding the grounding connection piece 22. Thus, the contact portion 22a of the ground connection piece 22 protrudes more toward the head substrate 4 than the contact portion 21a of the other connection piece 21. Further, the connection piece 22 and the connection piece 21 closest to the connection piece 22 are provided with an interval approximately twice the arrangement pitch of the connection pieces 21, but an empty groove 50 is formed between them. ing. That is, the grooves 50 are formed at equal intervals, and the thickness between the grooves 50 is set to be thin and uniform.
This prevents dimensional irregularities due to sink during molding.

Next, FIG. 2 shows the clamp mechanism 51.
The clamp mechanism 51 has a clamp shaft 53 having a flange 52 formed at one end, and a clamp lever 55 having a cylindrical fitting portion 54 rotatably fitted to the clamp shaft 53. A spiral cam 56 is formed at one end of the fitting portion 54 to be in contact with the spiral cam 40 (see FIG. 1) formed on the inner surface of the wall portion 37. At the other end, a helical cam 58 is formed which comes into contact with a helical cam 57 formed on the outer periphery of the clamp shaft 53 on the flange 52 side. The cams 56 and 58 of the clamp lever 55 are formed with their lead directions reversed.
The lead directions of the cams 40, 56 are equal, and the cams 57, 58
Are determined equally. Further, projecting pieces 59 are formed on both sides of the flange 52 of the clamp shaft 53, and receiving surfaces 60 for receiving these projecting pieces 59 are formed on both sides of the modified hole 41 of the first carriage frame 31. .

When assembling such a clamp mechanism 51, first, the ribs 42 of the second carriage frame 32 are fitted into the grooves 43 of the first carriage frame 31, and the ribs 4 of the first carriage frame 31 are fitted.
The first and second carriage frames 31 and 32 are slidably connected along the carrier shaft by engaging 4 with the claws 45 of the second carriage frame 32. Then
The wall portion 37 of the second carriage frame 32 is made to protrude to the maximum in the deformed hole 41 of the first carriage frame 31,
The clamp shaft 53 in which the fitting portion 54 of the clamp lever 55 is fitted is positioned between the support wall 33 and the wall portion 37 of the first carriage frame 31, and the projecting piece 59 of the flange 52 is received by the support wall 33. It is brought into contact with the surface 60. In this state, the support wall 33 is moved by the urging force of the spring 47 to the wall portion 37.
The distal end of the clamp shaft 53 is fitted to the wall 37 by moving the clamp shaft 53 to the side. Further, the clamp shaft 53 is prevented from rotating since the flange 52 is surrounded by a wall around the irregular hole 41.

Therefore, by rotating the clamp lever 55 in the clamp releasing direction, the spiral surfaces of the cams 40 and 56 are brought into full contact with each other and the cams 57 and 58 are contacted.
The second carriage frame 32 moves in a direction away from the support wall 33 by the biasing force of the spring 47 while making the spiral surface of the second contact entirely. Conversely, when the clamp lever 55 is rotated in the clamp direction, the cam 40
Presses the protrusion of the cam 56 toward the support wall 33, and the protrusion of the cam 58 presses the protrusion of the cam 57 toward the support wall 33,
The support wall 33 of the first carriage frame 31 is pushed toward the cartridge holding section 35. In other words, the cartridge holding portion 35 is pulled into the support wall 33 side.

When the ink cartridge 1 is mounted on the carriage 30 with such a structure, the support wall 33 and the cartridge holding portion 35 are rotated by rotating the clamp lever 55 in the clamp releasing direction as described above.
Increase the space between and. In this state, the support wall 33 can be separated from the cartridge holding portion 35 to the maximum by the urging force of the spring 47. Therefore, the openings 7 and 8 can be easily fitted to the cartridge holding portion 35 without causing the ink cartridge 1 to interfere with the protrusion 48 and the positioning portion 49.

In this state, the contact portion 22a of the grounding connecting piece 22 is located on the head substrate 4 side and above the contacting portion 21a of the other connecting piece 21. The contact portion 22a is elastically contacted with the metal surface (ground plane) of the head substrate 4, and subsequently, the contact portion 21a of the connection piece 21 of the connector 24 is elastically contacted with the contact 19 of the head substrate 4. . Therefore, even when the ink cartridge 1 is mounted in the cartridge holding portion 35 while the voltage is applied to the connection piece 21, the silicon substrate 2
It is possible to prevent the matrix circuit of 6 from being destroyed.

Further, since the connecting pieces 21 and 22 are formed of a metal plate having elasticity, it is possible to increase the amount of bending of the connecting pieces 21 and 22. As a result, the connecting piece 21 is formed.
Can be reliably brought into contact with the contact 19 and the connection piece 22 can be reliably brought into contact with the metal surface (ground surface) of the head substrate 4. Furthermore, since the amount of bending of the connection pieces 21 and 22 is large, fatigue can be prevented and reliability can be improved. In addition, since the rubber pad used in the related art can be omitted, the number of parts can be reduced and the cost can be reduced.

Then, as described above, when the clamp lever 55 is rotated in the clamp direction, the second carriage frame 32 moves in the direction in which the distance between the cartridge holding portion 35 and the support wall 33 becomes narrow. As a result, the head substrate 4 is pressed by the cartridge holding portion 35 and comes into contact with the projection 48 of the support wall 33, and the positioning portions 49 are fitted into the positioning holes 14 and 15.

In this state, the position of the head substrate 4 in the plane direction is determined by the positioning portion 49, and the flat surface 12 of the head substrate 4 is brought into contact with the tips of the three protrusions 48 located in the same vertical plane. As a result, the position and perpendicularity of the flat surface 12 in the direction along the carrier shaft becomes constant. Further, since the inkjet head 18 is formed integrally with the head substrate 4, the relative position of the inkjet head 18 with respect to the head substrate 4 can be accurately determined. Therefore, by positioning the head substrate 4, the position of the nozzle of the inkjet head 18 with respect to the recording medium can be determined very accurately.

Further, the support wall 33 of the first carriage frame 31 and the wall portion 37 of the second carriage frame 32.
The head substrate 4 can be reliably pressed against the projection 48 of the support wall 33 and the positioning holes 14 and 15 can be reliably engaged with the positioning portions 49 simply by widening the distance between the head substrate 4 and the projections 48 of the support wall 33 by the cams 40, 56, 57 and 58. . In this case, the clamp lever 5
5, cams 56 having different lead directions are provided at both ends of the fitting portion 54.
58 is formed, the cam 40 abutting on the cam 56 is formed on the wall 37, and the cam 57 abutting on the cam 58 is formed on the clamp shaft 53, so that the stroke of the clamp shaft 53 is increased. be able to. Accordingly, the distance between the support wall 33 and the cartridge holding portion 35 can be greatly increased, and therefore, the operation of attaching and detaching the ink cartridge 1 to and from the carriage 30 can be further facilitated. Of course, the pair of cams 40, 56 or the cam 5
Even if one of 7 and 58 is omitted, the distance between the support wall 33 and the cartridge holding portion 35 can be changed by operating the clamp lever 55.

Further, even if there is some variation in the relative position between the support wall 33 of the first carriage frame 31 and the cartridge holding portion 35 of the second carriage frame 32, the head substrate 4 is supported by the pressing body 39. It is possible to surely press the 33.

Further, the support wall 33 having the three protrusions 48 that abut the flat surface 12 of the head substrate 4 has the carriage 3
0, a silicon substrate 26 on which a heating element 27 as an ink discharge means is formed, and a silicon substrate 29 on which a large number of ink reservoirs 28 are formed, are laminated on the flat surface 13 of the head substrate 4. By this method, it is possible to extremely easily form the ink jet head 18 in which the nozzles 25 connected to the respective ink reservoirs 28 face the print medium.

The connector 24 is provided on the inner surface of the support wall 33, the contact 19 and the ink jet head 18 are formed on the flat surface 12 of the head substrate 4 on the support wall 33 side, and the head substrate 4 is supported by the cartridge holding portion 35. It is also possible to connect the contact 19 and the connector 24 by pressing against the wall 33.

[0036]

According to the first aspect of the present invention, a carriage provided so as to be reciprocally movable, an ink jet head having a large number of ink discharging means for individually discharging ink from nozzles, and an ink tank are integrally connected. An ink cartridge detachably mounted on the carriage, a wiring board having a number of contacts for input and provided on the ink cartridge, and a metal plate having elasticity, each of which is elastically attached to at least the contacts; A part of the large number of connecting pieces contacted with the carriage is fixed to an insulating material and is constituted by a connector attached to the carriage, so that when the ink cartridge is mounted on the carriage, each contact of the ink cartridge is connected to the carriage side. Although it is connected to the drive unit via the connecting piece, the connecting piece is made of a metal plate having elasticity, so that the connection is made. The amount of deflection of the piece can be increased, so that even if there is an error in the mounting dimension of the ink cartridge with respect to the carriage, the connecting piece can be reliably brought into contact with the contact or the like on the ink cartridge side. A second aspect of the present invention is capable of reducing the cost by reducing the number of connecting pieces that contact the contact points of the ink cartridge, and the ink before the connecting pieces contact the contact points. Since the connector having the grounding connection piece defined in a shape to be in contact with the ground surface of the cartridge is provided in the carriage, the signal from the drive unit is applied to the connection piece of the connector,
Even if you attach an ink cartridge to the carriage,
After the connecting piece for grounding is brought into contact with the grounding surface on the ink cartridge side, the other connecting piece can be brought into contact with the contact on the ink cartridge side, thereby preventing the circuit element on the ink cartridge side from being destroyed. Has the effect that can.

According to a third aspect of the present invention, in the first aspect, the insulator provided with a large number of grooves into which the connecting pieces are inserted is provided in the carriage. Therefore, each connecting piece is inserted into the grooves formed in the insulating body. By doing so, it is possible to maintain an insulating state between the connection pieces.

According to the invention of claim 4, in the invention of claim 1, since the bottom surfaces which are respectively brought into contact with the free ends of the connecting pieces and which define the returning positions of these connecting pieces are formed in the grooves of the insulator, the elastic means is elastic. By bringing the free end of each bending connection piece into contact with the bottom surface of the groove, the pressing force of each connection piece against the ink cartridge can be increased.

According to a fifth aspect of the present invention, in the second, third or fourth aspect, a contact portion protruding toward the ground plane side of the ink cartridge is formed on a part of the grounding connecting piece, and the ink cartridge is formed on the other connecting piece. Since the contact portion protruding from the contact side of the groove is formed and the depth of the bottom surface of the groove into which the connecting piece for grounding is inserted is made shallower than the depth of the bottom surface of the groove into which the other connecting piece is inserted, It is possible to project the contact portion of the connection piece of the above into the ground surface side of the ink cartridge side, and to keep the contact portions of the other connection pieces retracted from the contact portion of the connection piece for grounding. Even if the ink cartridge is mounted on the carriage while the signal from the drive unit is applied to the connection piece of, the contact piece on the ink cartridge side is contacted with the contact piece on the ink cartridge side after the connection piece for grounding is contacted with the ground surface of the ink cartridge side. Other connection Can be brought into contact with, thereby, an effect capable of preventing the destruction of the circuit elements of the ink cartridge.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a relationship between a head substrate and first and second carriage frames, according to an embodiment of the present invention, with an ink tank omitted.

FIG. 2 is an exploded perspective view showing first and second carriage frames and a clamp mechanism.

FIG. 3 is a perspective view showing a first carriage frame.

FIG. 4 is a perspective view showing a relationship between a head substrate and a connector.

FIG. 5 is an exploded perspective view of the ink cartridge.

FIG. 6 is an exploded perspective view showing a relationship between a contact point of a head substrate and a connection piece of a connector.

FIG. 7 is an enlarged front view showing the tip of the inkjet head.

FIG. 8 is a perspective view showing the inside of the ink cartridge.

FIG. 9 is a perspective view of the ink cartridge.

FIG. 10 is a perspective view showing a state in which a head substrate is fixed to a carriage without an ink tank.

FIG. 11 is a longitudinal sectional front view showing a connector support structure in a second carriage frame.

FIG. 12 is a perspective view of a state in which the entire ink cartridge is mounted on the carriage as viewed from the front.

FIG. 13 is a perspective view of a state in which the entire ink cartridge is mounted on the carriage as viewed from the rear.

FIG. 14 is a perspective view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink cartridge 3 Ink tank 18 Ink jet head 19 Contact point 21, 22 Connection piece 21a, 22a Contact part 23 Insulation material 24 Connector 25 Nozzle 27 Ink ejection means 30 Carriage 35 Insulator 50 Groove

Continuation of front page (72) Inventor Stephen Jay. Dettle USA New York 14580, Webster 311-01c Philips Roadville 800 Xerox In-house (72) Inventor Donald M. Stevens United States New York 14580, Webster 311-01c Philips Roadville 800 Xerox In-house (56) Reference JP-A-3-246038 (JP, A) JP-A-2-194956 (JP, A) SAIKAI HEI 4-33550 (JP, U)

Claims (5)

(57) [Claims] 1. A carriage reciprocally provided,
It has an ink cartridge detachably attached to the carriage, which is formed by integrally connecting an ink jet head having a large number of ink ejecting means for individually ejecting ink from nozzles, and an ink tank, and a large number of input contacts. And a wiring board provided in the ink cartridge, and at least a part of a large number of connecting pieces that are elastically contacted with the contacts and are formed of a metal plate having elasticity, are fixed to an insulating material, and A driving device for an ink jet printer, which comprises an attached connector. 2. A large number of connecting pieces for contacting the contacts of the ink cartridge, and a grounding connection shaped to make contact with the ground plane of the ink cartridge before these connecting pieces make contact with the contacts. The drive device for an ink jet printer according to claim 1, wherein a connector having one piece is provided on the carriage. 3. The driving device for an ink jet printer according to claim 1, wherein the carriage is provided with an insulator having a large number of grooves into which the connecting pieces are inserted. 4. The driving device for an ink jet printer according to claim 1, wherein bottom surfaces of the connecting pieces, which are in contact with the free ends of the connecting pieces and define the return positions of the connecting pieces, are formed in the grooves of the insulator. . 5. The grounding connection piece is formed with a contact portion projecting toward the ground surface side of the ink cartridge, and the other connection piece is formed with a contact portion projecting toward the contact side of the ink cartridge. 5. The inkjet printer drive according to claim 2, 3 or 4, wherein the depth of the bottom surface of the groove into which the connection piece for insertion is inserted is shallower than the depth of the bottom surface of the groove into which the other connection piece is inserted. apparatus.