JP2003065406A - Belt tension applicator and recording device equipped with it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt tension applicator capable of being embodied at a low cost and exerting a high stability when the applicator is in high speed operation. SOLUTION: A power transmission device 50 uses a drive motor 69 as a drive source and transmits the power to a transmission gear 49, etc., by a pinion 78 mounted on a drive shaft 69a and an endless belt 51 set around the pinion 78. A frame 61 is furnished with a guide hole 75 in which a bearing part 69b slides, and a tension is given to the endless belt 51 by a spring 71 installed between the drive motor 69 and frame 61. The drive motor 69 is fixed by a stationary screw 74 and a pin 72 under the condition that the tension of the belt 51 is balanced with the spring force of the spring 71 to maintain a properly tensioned condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt tension applying device for applying a predetermined tension to an endless belt that is engaged with a drive shaft of a drive motor and at least two or more rotating shafts. The present invention also relates to a recording device that is provided with the belt tension applying device and that records on a recording material.

[0002]

2. Description of the Related Art An endless belt, which is engaged with a drive shaft of a drive motor and a plurality of rotation shafts to transmit the power of the drive motor to the plurality of rotation shafts, is driven by a tension state of the endless belt. Good or bad, especially stability at high speed operation is determined, so it is desirable that the endless belt be given appropriate tension. Therefore, in order to properly maintain the tension state of the endless belt, there may be used a configuration in which, for example, a driven roller for tension adjustment is provided between any two rotary shafts and the tension is adjusted by the driven roller.

More specifically, the driven roller is provided so as to be displaceable in a tension increasing direction and a tension decreasing direction, and
The urging means (for example, a spring) is always urged in the tension increasing direction. Therefore, the endless belt is operated in such a state that the tension of the endless belt and the urging force of the urging means are balanced by the driven roller thus configured.

[0004]

However, when the driven roller as described above is provided, the driven roller can be displaced in the direction of increasing the tension and the direction of decreasing the tension, so that the driving state of the belt becomes unstable during high speed operation. At the same time, the provision of the driven roller increases the cost.

Therefore, the present invention has been made in view of such a situation, and an object thereof is to obtain a belt tension applying device which can exhibit high stability at high speed operation at low cost.

[0006]

In order to solve the above-mentioned problems, the belt tension imparting device according to claim 1 of the present invention comprises:
A belt tension imparting device for imparting a predetermined tension to an endless belt which is engaged with a drive shaft of a drive motor and at least two or more rotating shafts, wherein the drive shaft is inserted through the belt tension applying device. A guide hole extending in a frame member to which the drive motor is attached, the guide hole being slidable in a tension increasing direction and a tension decreasing direction,
And a fixing means for fixing the drive motor to the frame member in a balance state of the tension of the endless belt and the urging force of the urging means. Is characterized by.

According to the first aspect of the present invention, the belt tension imparting device capable of exhibiting high stability even at high speed operation at low cost is provided without providing the endless belt with the driven roller for tension adjustment. be able to. That is, a drive motor in which an endless belt is engaged with a drive shaft is slidably provided in a frame member to which the drive motor is attached in a direction of increasing and decreasing a tension of the endless belt, and the drive motor is energized. The device is urged in the direction of increasing the tension, and the urging force of the urging device applies the tension.

The belt tension applying device is provided with fixing means for fixing the drive motor to the frame member in a state where the tension of the endless belt and the urging force of the urging means are balanced. Therefore, by the fixing means, the drive motor can exhibit high stability without displacing its position even during high-speed operation, and the desired tension can be maintained for a long period of time. It can be maintained stably.

According to a second aspect of the present invention, in the belt tension imparting device according to the first aspect, the clearance between the outer periphery of the bearing portion of the drive shaft that slides on the inner periphery of the guide hole and the inner periphery of the guide hole is small. It is characterized in that it is configured. According to the invention of claim 2 of the present application, the clearance between the outer circumference of the bearing portion of the drive shaft that slides on the inner circumference of the guide hole and the inner circumference of the guide hole is small. The drive motor slides without rattling, and therefore, the fixed position of the drive motor is uniformly determined without variation, so that the desired tension state can be surely realized.

A belt tension applying device according to claim 3 of the present application is the device according to claim 1 or 2, wherein the fixing means is
From a screw insertion hole extending in the frame member in parallel with the extending direction of the guide hole, and a fixing screw inserted into the screw insertion hole and screwed into the screw hole formed in the drive motor. And the biasing means comprises a tension coil spring attached between a first spring retaining portion provided on the drive motor and a second spring retaining portion provided on the frame member. It is characterized by

According to the third aspect of the present invention, since the fixing means is a fixing screw which is screwed into the screw hole formed in the drive motor, the fixing means of the drive motor is simple and inexpensive. In addition, since the urging means is composed of a tension coil spring, the urging means can also be constructed at a low cost with a simple structure.

The belt tension applying device according to claim 4 of the present application is the belt tension applying device according to claim 3, wherein the first spring retaining portion is
A pin which is inserted into a pin insertion hole extending in the frame member in a direction parallel to the extending direction of the guide hole, and in which a screw portion formed at a tip end is screwed into a screw hole formed in the drive motor. It is characterized by being made of a member.

According to the fourth aspect of the present invention, since the first spring retaining portion is a pin member that is inserted into a pin insertion hole that extends parallel to the extending direction of the guide hole,
With the pin insertion hole and the pin member, the sliding direction of the drive motor can be regulated more reliably.

According to a fifth aspect of the present invention, in the belt tension applying device according to the fourth aspect, the clearance between the pin member and the inner circumference of the pin insertion hole is small.

According to the fifth aspect of the present invention, since the clearance between the pin member and the inner circumference of the pin insertion hole is small, the pin member slides without rattling. Therefore, it becomes possible to more reliably regulate the sliding direction of the drive motor.

A belt tension imparting device according to claim 6 of the present application is the device according to claim 4 or 5, wherein the pin member is
It is characterized in that it is configured so as to also serve as the fixing means by being screwed into a screw hole formed in the drive motor while sandwiching the frame member with the drive motor.

According to the sixth aspect of the present invention, the pin member is pinched between the frame member and the drive motor and is screwed into a screw hole formed in the drive motor to fix the fixing means. The drive motor can be more firmly fixed to the frame member.

A belt tension imparting device according to a seventh aspect of the present invention is characterized in that, in any one of the first to sixth aspects, the drive motor is urged straight in the extending direction of the guide hole. To do.

According to the invention of claim 7, the drive motor is urged straight in the extending direction of the guide hole, so that the drive shaft sliding on the inner circumference of the guide hole or the drive shaft The bearing portion of the drive shaft does not press strongly against the inner circumference of the guide hole, and the endless belt can be provided with a small transmission loss of the urging force of the urging means, thereby achieving the desired tension state. You can

In the recording apparatus according to claim 8 of the present application, the recording section for recording on the recording material, the conveyance drive roller for conveying the recording material to the recording section at a constant pitch, and the recording section perform recording. A paper discharge drive roller for discharging the recording material, and driving the transport drive roller and the paper discharge drive roller,
A recording apparatus comprising: the drive motor according to any one of claims 1 to 7, wherein a gear that rotates the transport drive roller, and a gear that rotates the discharge drive roller; A pinion gear provided on the drive shaft of the drive motor, and a belton tensioning device according to any one of claims 1 to 7, which applies tension to an endless belt that is engaged with the pinion gear. Characterize.

According to the eighth aspect of the present invention, in the recording apparatus for recording on the recording material, the gear for rotating the conveying drive roller, the gear for rotating the paper discharge drive roller, and the drive motor drive. The pinion gear provided on the shaft and the endless belt that is engaged with the endless belt are tensioned.
Since the belt tensioning device according to any one of claims 1 to 7 is provided, the same operation as the invention according to any one of claims 1 to 7 of the present application in the recording device for recording on a recording material is performed. The effect can be obtained.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. <Structure of Apparatus Main Body of Inkjet Printer> The structure of the apparatus main body of the inkjet printer according to the embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Here, FIG. 1 is an external perspective view of an apparatus main body of the inkjet printer (hereinafter abbreviated as “printer”) 100, FIG. 2 is the same exploded perspective view, FIG. 3 is the same side sectional view, and FIG. It is a figure.

In FIG. 1 and FIG. 2, the printer 100 is divided into a plurality of units, and the plurality of units are combined to form the main unit. In the figure, reference numeral 1 is a paper feeding unit as a paper feeding device capable of feeding a paper P (see FIG. 3) as a recording material or roll paper (not shown), and reference numeral 20 is an inkjet recording head 24 (see FIG. 3)), a carriage unit including a carriage 22 having a carriage 22 having a reference numeral 60, a conveyance unit 60 for conveying a recording material, and a reference numeral 80 an ink system unit for performing maintenance of the inkjet recording head 24. Is divided into these four units as shown in FIG.
It is constructed by combining two units as shown in FIG. Incidentally, in the present embodiment, the carriage unit 20 and the ink system unit 80 are respectively the upper side and the right side of the transport unit 60 (the right side in FIG. 4).
And the paper feeding unit 1 is connected to the carriage unit 20.
The four units are configured to be united by connecting to the back side of the.

Next, referring to FIG. 3, the printer 100
The paper transporting route will be described. In addition, in the following, FIG.
The left side (rear side of the printer 100) is referred to as “upstream side”, and the right side of FIG. 3 (front side of the printer 100) is referred to as downstream side. The printer 100 is provided with a hopper 6 on the upstream side, and the sheets P as cut sheets are accumulated and stored on the hopper 6 in an inclined posture. The hopper 6 is rotatably provided in a clockwise direction and a counterclockwise direction in FIG. It is designed to be pressed and separated. Further, the hopper 6 is provided with a movable guide 4 that can slide in the width direction of the paper P (see FIG. 1), and a fixed guide 5 (see FIG. 1).
(See reference), the side edge of the accumulated paper P is guided.
Then, the topmost one of the accumulated sheets P is the hopper 6
Performs a pressure contact operation with respect to the paper feed roller 3, and in the pressure contact state, the paper feed roller 3 rotates and is fed to the downstream side. The paper feed roller 3 has a substantially D-shape when viewed from the side, and is rotated when the rotation shaft 3a is driven to rotate. The paper feed roller 3 is controlled so that the flat portion thereof faces the paper P during the printing operation (the state of FIG. 3), thereby preventing the paper P from being conveyed.

Next, a paper guide 67 as a plate-like member is provided substantially horizontally below the paper feed roller 3, and the front end of the paper P fed out by the paper feed roller 3 is provided in the paper guide 67.
It obliquely abuts and is smoothly guided to the downstream side. The transport drive roller 62 that is rotationally driven downstream from the paper guide 67.
And the transport driven roller 6 that is in pressure contact with the transport drive roller 62.
3 is provided, the sheet P is nipped between the conveyance driving roller 62 and the conveyance driven roller 63, and is conveyed to the downstream side at a constant pitch.

The transport driven roller 63 is axially supported on the downstream side of the transport driven roller holder 64, and the transport driven roller holder 64 rotates in the clockwise direction and the counterclockwise direction in FIG. 3 about the rotation shaft 64a. The transport driven roller 63 is rotatably biased in a direction in which the transport driven roller 63 is constantly in pressure contact with the transport drive roller 62 (clockwise direction in FIG. 3) by a torsion coil spring (not shown). The transport drive roller 62 is composed of a rotary shaft that is long in the main scanning direction. Therefore, in the present embodiment, the transport drive roller 62 and the transport drive roller 62 are provided.
Is the same as the rotation axis of.

Next, in the vicinity of the conveyance driven roller holder 64 located on the most one-digit side (on the right front side in FIG. 2), the sheet detection consisting of the sensor body 36b and the detector 36a for detecting the passage of the sheet P is detected. A container 36 is provided. Detector 36a
Is formed in a substantially V shape in a side view, and is rotatably provided in a clockwise direction and a counterclockwise direction in FIG. 2 around a rotation shaft 36c near the center thereof. The sensor main body portion 36b located above the detector 36a includes a light emitting portion (not shown) and a light receiving portion (not shown) that receives light from the light emitting portion, and the sensor main portion 36b is placed above the rotating shaft 36c of the detector 36a. The rotation operation blocks and passes the light traveling from the light emitting section to the light receiving section. Therefore, as shown in FIG. 3, when the detector 36a is rotated so as to be pushed upward with the passage of the paper P, the upper side of the detector 36a is disengaged from the sensor body 36b, whereby the light receiving portion is in the light receiving state. Therefore, the passage of the paper P is detected.

Then, downstream of the transport drive roller 62,
The platen 66 and the inkjet recording head 24 are arranged so as to face each other vertically. The platen 66 is long in the main scanning direction (see FIG. 2), and the paper P conveyed below the inkjet recording head 24 by the rotation of the conveyance driving roller 62 is supported from below by the platen 66. The ink jet recording head 24 is the ink cartridge 2
The carriage 22 is provided at the bottom of the carriage 22 for mounting the carriage 3. The carriage 22 reciprocates in the main scanning direction while being guided by a carriage guide shaft 25 extending in the main scanning direction. still,
In this embodiment, the ink cartridge 23 is composed of four cartridges as shown in FIG. 4, that is, four cartridges in which four color inks (black, yellow, cyan, and magenta) are separately and independently filled. It can be exchanged separately.

Next, a sheet discharge section of the printer 100 is provided downstream from the ink jet recording head 24, and a sheet discharge drive roller 65, a sheet discharge driven roller 31, and a sheet discharge auxiliary roller 32 are arranged. . A plurality of paper ejection drive rollers 65 are attached in the axial direction of the paper ejection drive roller shaft 65a that is rotationally driven (see FIG. 4), and the paper ejection driven roller holder 3
The paper discharge driven roller 31 pivotally supported by 1a is provided so as to be driven to rotate by being lightly pressed against the paper discharge drive roller 65. Therefore, the paper P printed by the inkjet recording head 24 is rotated in a state where it is nipped by the paper ejection drive roller 65 and the paper ejection driven roller 31, so that the paper ejection direction (FIG. Three
Is discharged in the direction of arrow). The paper ejection auxiliary roller 32 pivotally supported by the paper ejection auxiliary roller holder 32a is provided on the slightly upstream side of the paper ejection driven roller 31, and presses the paper P slightly downward from the platen 66 of the paper P. Lifting is prevented and thus the distance between the paper P and the inkjet recording head 24 is regulated.

Here, the hopper 6, the movable guide 4, the fixed guide 5, and the paper feed roller 3 described above are provided in the above-mentioned paper feed unit 1 shown in FIGS. As shown in FIG. 2, the sheet feeding unit 1 includes a mounting portion right 2a and a mounting portion left 2 which are vertically arranged on both sides of a hopper 6 and have a substantially columnar shape.
The base of the paper feeding unit frame 2 is provided with a rotary shaft 3a of the hopper 6 and the paper feeding roller 3.
Etc. are provided in the paper feeding unit frame 2.
Then, the paper feeding unit 1 includes the mounting portion 2a and the mounting portion 2b.
Is connected to the back side of the carriage unit 20 at the upper part of the.

Next, the paper guide 67 and the conveyance drive roller 6
2, transport driven roller holder 64, paper ejection drive roller shaft 65
a is provided in the transport unit 60 shown in FIGS. 1 and 2. As shown in FIG. 2, the transport unit 60 includes a transport unit frame 61 having a substantially U-shaped plan view as a base body, a power supply unit 68 that is a power supply unit of the printer 100 at the rear, and a paper discharge at the front. The drive roller shaft 65a is attached to the transport drive roller 62 in the middle of the main body.
Further, a platen 66 is provided in the upper front part, and a transport driven roller holder 64 is provided in the middle upper part. In the lower left part of the transport unit 60, a drive that serves as a common drive source for the paper feed roller 3, the transport drive roller 62, the paper discharge drive roller 65, a pump device 82 described later, and the blade unit 84. A motor 69 (see FIG. 4) is provided. Power transmission from the drive motor 69 to the paper feed roller 3, the transport drive roller 64, and the paper discharge drive roller 65 is performed by a power transmission device 50, which will be described later, provided on the left side surface of the transport unit 60. The power transmission to the pump device 82 and the blade unit 84 provided on the right side surface of the paper is carried out via the paper ejection drive roller shaft 65a, and a power transmission device (gear device not shown) provided at the right end of the paper ejection drive roller shaft 65a. ).

Connected to the right side of the transport unit 60,
The ink system unit 80 as a maintenance means of the inkjet recording head 24 includes a frame 81, which is connected to the right side surface of the transport unit frame 61 and serves as a base of the unit, as shown in FIG.
Further, a cap device 83, a pump device 82, and a blade unit 84 are provided. The cap device 83 protects the nozzle surface (not shown) by capping the inkjet recording head 24 when the carriage 22 moves to the home position (in the area a _{1 in} FIG. 4), and the pump device 82 is in the cap state. A negative pressure is supplied to the cap device 83 to suck ink from the nozzle openings of the inkjet recording head 24. Further, the blade unit 84 is used for the carriage 22.
Reciprocating region and position across the a position retracted from the reciprocating area have movable, moves to a position crossing the reciprocating area of the carriage 22, and a ₀ region of the carriage 22 is print area (Fig. 4 ) To the home position (Fig. 4
By moving the to a ₁ zone), or by moving in the opposite direction, for cleaning by wiping the nozzle surface of the inkjet recording head 24 (not shown).

The carriage guide shaft 25 and the paper detector 36 are provided in the carriage unit 20. As shown in FIG. 2, the carriage unit 20 includes a main frame 21a, a side frame right 21b and a side frame left 21c that are erected on both sides of the main frame 21a. 25 is pivotally supported.

Further, as shown in FIG. 4, the carriage unit 20 is provided with a carriage motor 27 on the rear surface on the left side of the unit, and a drive pulley 28 is attached to the carriage motor 27. A driven pulley 29 is provided on the right side of the unit, a carriage belt 26 is hung between the drive pulley 28 and the driven pulley 29, and a part of the carriage belt 26 is fixed to the carriage 22. . Therefore, the carriage 22 reciprocates in the main scanning direction (left and right direction in FIG. 4) by the rotation of the carriage motor 27.

Although the paper discharge frame 30 is attached to the carriage unit 20 side in FIG. 2, the paper discharge frame 30 can be attached to the carriage unit 20 side or the transport unit 60 side. It is possible to belong to either side. The above is the configuration of the apparatus main body of the printer 100, and the printer 100 becomes movable by combining and connecting the four units.

<Structure of Power Transmission Device> Next, the structure of the power transmission device 50 provided on the left side surface of the transport unit 60 will be described with reference to FIGS. here,
5 is a left side view of the transport unit 60, and FIG. 6 is a rotation shaft 48.
FIG. 7 is an enlarged view of the shaft end portion of FIG. 7, and FIG. 7 is a perspective view of the power transmission device 50.

In FIG. 5, the drive motor 69, which is the drive source of the power transmission device 50, has a lower front side (the left side surface in FIG. 4) of the left side surface (the left side surface in FIG. 4) of the transfer unit frame 61 which is the base of the transfer unit 60. (Lower right)
The transport drive roller 62, the paper discharge drive roller shaft 65a, and the paper feed roller shaft 3a (see FIG. 3) described above with reference to FIG.

A pinion gear 78 is attached to the drive shaft 69a of the drive motor 69, and the pinion gear 78, a transmission gear 49 provided above the drive motor 69, and a transmission provided in the middle of the rear of the carrying unit frame 61. An endless belt 51 to which a tension is applied by a belt tension applying device 70 described later is wound between the gear 52 and the gear 52. Therefore, when the drive motor 69 rotates, the transmission gears 49, 52 are transmitted via the endless belt 51.
Rotate at the same time.

The transmission gear 49, which is rotatably driven around the rotation shaft 49a, is attached to the gear (not shown) with which the endless belt 51 meshes and the shaft end of the paper discharge drive roller shaft 65a. The discharge driving roller gear 65b is a two-stage gear composed of a gear (not shown) meshing with the discharge driving roller gear 65b. Therefore, the discharge driving roller shaft 65a is rotationally driven by this.

The transmission gear 52 rotatably driven by the rotation shaft 48 is a two-stage gear like the transmission gear 49, and the endless belt 51 engages with the transmission gear 52a.
And a gear 52b that engages with the transport drive roller gear 62b attached to the shaft end of the transport drive roller 62 are integrally formed, and are provided so as to be rotatable about the rotary shaft 48. Therefore, as a result, the transport drive roller 62 is rotationally driven.

A disc-shaped scale 41 constituting the encoder 40 is attached to the transmission gear 52. The encoder 40 includes a sensor holder 53 attached to the transport unit frame 61, a photo interrupter (optical sensor) 44 attached to the sensor holder 53, and a disc-shaped scale 41. The photo interrupter 44 is attached to the sensor holder 53 with the printed circuit board 45 attached, and is connected to a control device (not shown). The photo interrupter 44 receives a light emitting unit (not shown) and light emitted from the light emitting unit, and a light receiving unit (not shown) provided at a distance from the light emitting unit.
And the outer peripheral portion of the disk-shaped scale 41 is sandwiched between them.

The disc-shaped scale 41 has a light-transmitting portion (not shown) and a light-shielding portion (not shown), which have substantially the same width, and are alternately formed on the outer peripheral portion thereof at a constant pitch in the circumferential direction. It has a slit-shaped rotation detection pattern (not shown). Then, when the disc-shaped scale 41 rotates,
The photointerrupter 44 repeats transmission and blocking of light by the rotation detection pattern, and the photointerrupter 44 outputs a rectangular wave signal that alternately repeats ON and OFF to a control device (not shown) of the printer 100.
The control unit (not shown) of the printer 100 obtains the carry amount of the paper P from the number of the rectangular waves, and also obtains the carry speed of the paper P from the repetition period of the rectangular waves.

Here, the rotation shaft 48, which is the rotation shaft of the transmission gear 52 and the disc-shaped scale 41, is locked by the shaft stop member 56. That is, as shown in FIG.
Is a ring-shaped member that fits in a groove 48a formed along the circumferential direction at the shaft end of the rotating shaft 48.
The transmission gear 52 and the disc-shaped scale 41 are held between the transport unit frame 61 and the rotary shaft 48 at the same time. As shown in FIG. 6, half (upper side in FIG. 6) of the shaft stopper member 56 has a ring shape (circular shape) in plan view.
And the remaining half (the lower side in FIG. 6) has a square shape, and the knob 56 is formed by the corner of the square shape.
b and 56b are formed. Further, a slit 56a is formed in the vicinity of the middle of the rectangular shape, by which the pinch portions 56b and 56b are pinched by tweezers or the like, and twisted so that they are staggered so that the shaft stopper member 56 can be easily attached. It can be removed from the groove 48a. Therefore, for example, even when disassembling the printer 100, the disassembling work becomes easy, and the printer 1
The components of 00 are easily recycled. The shaft stopper member 56 is also used for another rotation shaft, for example, the paper discharge drive roller shaft 65a as shown in FIG.

Next, a transmission gear 50 that meshes with the conveyance drive roller gear 62b is provided behind the conveyance drive roller gear 62b (on the left side in FIG. 5). The transmission gear 59 provided on the side is engaged with the sheet feeding unit 1 by being connected to the carriage unit 20. Accordingly, this causes the paper feed roller shaft 3a (see FIG. 3) to rotate.

The above is the general structure of the power transmission device 50 provided on the left side surface of the transport unit 60. Next, the belt tension applying device 70 for applying an appropriate tension to the endless belt 51 will be described in detail. In FIG. 7, a belt tension imparting device 70 for imparting tension to the endless belt 51 includes a guide hole 75 formed in the transport unit frame 61 for inserting the drive shaft 69 a of the drive motor 69 and the drive motor 69 into the endless belt 51. A tension coil spring 71 as an urging means for urging in the direction of increasing the tension, a fixing screw 74 for fixing the drive motor 69 to the transport unit frame 61, and a pin member 72 as a "first engaging portion". , And a spring retaining portion 73 as a “second engaging portion”.

The guide hole 75 is provided in the carrying unit frame 61.
In the vertical direction (direction from the upper rear side of the printer 100 toward the lower front side of the apparatus), the drive motor 6
The drive shaft 69a of 9 is inserted, and the bearing portion 69b of the drive motor 69 slides along the inner circumference of the guide hole 75. The clearance between the outer periphery of the bearing portion 69b and the inner periphery of the guide hole 75 is formed to be small, which allows the drive motor 69 to linearly slide in the extending direction of the guide hole 75 without rattling. Has become.

Upper left of the guide hole 75 (upper left in FIG. 5:
A screw insertion hole 77 extends in the same direction as the guide hole 75 at the device rear upper side), and a pin insertion hole 76 is inserted at the lower right of the guide hole 75 (lower right in FIG. 5: lower front of the device). Like the hole 77, it extends in the same direction as the extending direction of the guide hole 75. A fixing screw 74 that is screwed into a screw hole (not shown) formed in the drive motor 69 is inserted into the screw insertion hole 77, and the pin insertion hole 76 is formed in the drive motor 69 similarly to the fixing screw 74. A pin member 72 screwed into a screw hole (not shown) provided is inserted, and these are driven motors 69.
It is slidable in the same direction as the (bearing portion 69b).

Here, the non-screw portion 72a of the pin member 72 is a member that is long in the axial direction of the drive shaft 69a, and the screw portion (not shown) formed at the tip end thereof is the drive motor 6 as described above.
A portion that is screwed into a screw hole (not shown) formed in 9 and slides with the pin insertion hole 76 is a non-screw portion 72b (see FIG. 5) having substantially the same width as the pin insertion hole 76. As a result, the non-threaded portion 72b slides in the pin insertion hole 76 without rattling. And further pin member 7
2 has a stepped shape in which the transport unit frame 61 is pinched between the drive motor 69 and the non-screw portion 72a having a diameter larger than that of the non-screw portion 72b that slides with the pin insertion hole 76. Together with the fixing screw 74, it has a function as a fixing means for fixing the drive motor 69 to the transport unit frame 61.

Next, the guide hole 75, the screw insertion hole 77, and the pin insertion hole 76 described above, the drive shaft 69a,
The fixing screw 74 and the pin member 72 are extended in the same direction so as to slide on the same straight line, and further, on the extension line of the straight line, a spring hook as a "second spring hook portion" is provided. A stop 73 is provided on the transport unit frame 61. A tension coil spring 71 as an urging means is attached to the spring retaining portion 73 and the pin member 72, so that the drive motor 69 is pulled straight in the extending direction of the guide hole 75. ing. Therefore,
The pulling direction is the tension increasing direction of the endless belt 51, and the opposite direction is the tension decreasing direction.

The operation and effect of the belt tension applying device 70 for applying a tension to the endless belt 51 having the above structure will be described below. As described above, the drive motor 69 is slidable in the extending direction of the guide hole 75 by the tension coil spring 71, and the urging force of the tension coil spring 71 can apply appropriate tension to the endless belt 51. It has become. Therefore, for example, between the pinion gear 78 and the transmission gear 49,
The belt tension applying device 70 that applies tension to the endless belt 51 at low cost is configured without the need to separately provide a driven roller for applying tension.

Next, the drive motor 69 is slidably provided, and is fixed to the transport unit frame 61 with a simple and inexpensive structure by the fixing screw 74 and the pin member 72. Therefore, by the fixing means including the fixing screw 74 and the pin member 72, the drive motor 69 does not slide even at the time of high-speed operation, and thus high stability can be exhibited, and a desired proper tension can be obtained. It is possible to maintain a stable state for a long period of time.

The inner circumference of the guide hole 75 and the bearing portion 75
Since the clearance between the drive motor 69 and the outer circumference of the drive motor 69 is small, the drive motor 69 slides without rattling, and therefore the fixed position of the drive motor 69 is uniformly determined without variation. Quality can be kept constant between devices. Further, the pin member 72 is also configured to slide in the pin insertion hole 76 without rattling, so that the fixing position of the drive motor 69 is more uniformly determined, and the above-described action and effect are further enhanced. You can get more.

In addition, since the pin member 72 and the tension coil spring 71 are arranged in the outer region of the endless belt 51, the biasing force is applied to the drive motor 69 in a stable state on the side far from the endless belt 51. It becomes possible to do. Further, as described above, the drive motor 69 is connected to the guide hole 7
Since the bearing portion 69b is not urged against the inner circumference of the guide hole 75, the bearing portion 69b does not come into pressure contact with the inner periphery of the guide hole 75, so that the urging force of the tension coil spring 71 is accurately transmitted without loss. It can be applied to the belt 51.

<Structure of Motor Positioning Device> Next, the drive motor 69 described above is positioned by the motor positioning device 200 described below so as to be attached to the transport unit frame 61 in a more appropriate state, and then the transport unit frame is moved. It is attached to 61. Below, FIG.
Through FIG. 10, the motor positioning device 20
The configuration of 0 will be described. Here, FIG. 8 is an external perspective view of the motor positioning device 200, FIG. 9 is a side view (partially sectional view) of the motor positioning device 200, and FIG.
FIG. 10B is a sectional view taken along line xx in FIG.

In FIG. 8, the motor positioning device 200
Is a frame mounting plate 101 made of a plate-like body, and a right-angled triangular shape in a side view, which stands upright in the vicinity of both side ends of the frame mounting plate 101 and supports the frame mounting plate 101 in an inclined posture. The supporting plate 102 (only one side is shown in FIG. 8) constitutes a main body. The transport unit frame 61 is placed on the frame placing plate 101 so as to be in an inclined posture, and the holding blocks 103 and 104 provided on the frame placing plate 101 allow the carrying unit frame 61 to move downward and sideward (in FIG. 8). It is held so that it does not move to the left). That is, the frame mounting plate 101,
The holding blocks 103 and 104 configure the “frame member supporting means” of the transport unit frame 61.

Further, a rectangular window hole portion 101a is formed at a position slightly upper right of the center of the frame mounting plate 101, and the motor supporting means 110 for supporting the drive motor 69 from the window hole portion 101a. Is exposed.
The motor support means 110, as shown in FIG.
9 and a motor support portion 111 for supporting the motor support portion 1.
A base portion 112 to which 11 is attached and which has an inverted T-shape when viewed from the front, and a linear guide 11 for sliding the base portion 112 smoothly in the horizontal direction (the arrow direction in FIG. 9)
3 and 3.

Next, returning to FIG. 8, a protection plate 115 having two cylindrical members 114, 114 is provided upright on the right side end of the motor mounting plate 101. The protective plate 115 is
When the tension of the endless belt 51 is adjusted while rotating the drive motor 69, the cylindrical members 114 and 114 are protective members provided for safety of work so that fingers are not caught in the endless belt 51. , The above-mentioned fixing screw 7
4 performs a function of a guide member for vertically abutting the driver toward the fixing screw 74 and the pin member 72 when fastening the fixing screw 74 and the pin member 72, thereby fastening the fixing screw 74 and the pin member 72. However, many people can do it easily, properly and uniformly.

Next, a power supply connector 105 and a power switch 106 are provided on the slightly upper left side of the motor supporting means 110.
Is provided. The drive motor 69 supported by the motor support means 110 is connected to the power supply connector 105, and is rotated when the power switch 106 is turned on.

A frame pressing means 108 is provided near the upper right corner of the frame mounting plate 101. The frame pressing means 108 is a lever device having an elastically deformable elastic member 108a.
When a is pressed against a part of the transport unit frame 61, the transport unit frame 61 is pressed from above (see FIG. 10A) so that the transport unit frame 61 does not float upward during positioning of the drive motor 69. It plays the function of holding down.

Next, a method of positioning the drive motor 69 using the motor positioning device 200 configured as described above will be described. First, the fixing screw 74 and the pin member 72 shown in FIG. 7 are lightly tightened, the drive motor 69 is temporarily fixed to the transport unit frame 61, the endless belt 51 is rotated, and the transport unit frame 61 is framed in this state. It is placed on the placing plate 101. At this time, the inclination angle of the frame mounting plate 101 is set to the guide hole 7 shown in FIG.
The inclination angle of 5 (the angle formed by the extending direction of the guide hole 75 and the horizontal direction) is set to the same angle. Therefore, when the transport unit frame 61 is mounted on the frame mounting plate 101, the guide hole 75 is formed. Is in a state of extending horizontally as shown in FIG. When the transport unit frame 61 is mounted on the frame mounting plate 101, the drive motor 69
However, as shown in FIG. 10A, the transport unit frame 61 is placed so as to be supported by the motor support portion 111. Since the support surface of the support portion 111 has a concave shape (V shape in the present embodiment) as shown in FIG. 10B, this supports the drive motor 69 on the support portion 111 without rolling. You can do it.

Next, in FIG. 9, the fixing screw 74 and the pin member 72 are loosened. At this time, the drive motor 69 is supported in a horizontal posture (horizontal direction in FIG. 10A) by the motor support portion 111 and is slidable in the arrow direction in FIG. 9, so that the fixing screw 74 and the pin member are provided. 72
By loosening, the drive motor 69 slides to a position where the spring force of the tension coil spring 71 and the tension of the endless belt 51 are in a balanced state, and stops at that position. At this time, the fixing screw 74 and the drive shaft 69
Since a, the pin member 72, and the spring retaining portion 73 are linearly arranged along the extending direction of the guide hole 75,
The bearing portion 69b is urged straight in the extending direction of the guide hole 75, whereby the drive shaft 69b does not come into pressure contact with the inner circumference of the guide hole 75, and therefore the urging force of the tension coil spring 71 is applied to the endless belt 51 as it is. Therefore, it is possible to set an appropriate tension.

Next, the drive motor 69 is connected to the power supply connector 105, the power switch 106 is turned on, and the endless belt 51 is operated. By operating the endless belt 51, the tension distribution of the endless belt 51 becomes uniform, the axial position of the drive shaft 69b of the endless belt 51 becomes stable, and the fixing screw 74 and the pin member 72 are fastened in this state. Then, the drive motor 69 is securely fixed to the transport unit frame 61. 8 and 10
In FIG. 10A, reference numeral 107 is a screw fastening holding portion that holds the transport unit frame 61 so as not to move in the screw fastening direction (rightward in FIG. 10A) when fastening the fixing screw 74 and the pin member 72. Shows the holding block of.

Therefore, according to the above, the motor positioning device 2
00 has the following effects. That is, since the motor positioning device 200 supports the drive motor 69 in the horizontal posture, the drive motor 69 is not fixed in the inclined posture by this, and the tension of the endless belt 51 and the spring force of the tension coil spring 71 described above are exerted. Is balanced, that is, the drive motor 69 can be fixed without breaking the proper tension state. Further, the motor positioning device 200 supports the transport unit frame 61 so that the guide holes 75 extend in the horizontal direction, and slides the drive motor 69 in the horizontal direction.
The endless belt 5 described above is thus provided.
In the balanced state of the tension of 1 and the spring force of the tension coil spring 71, the self-weight of the drive motor 69 is not applied to the endless belt 51, and the tension coil spring 71
It is possible to form the tension state of the endless belt 51 as it is and to accurately apply the target tension.

In the present embodiment, the motor holding means 110 supports the rear portion of the drive motor 69 as shown in FIG. 10A, and the motor support portion 111 and the guide hole 75 cause the drive motor 69 to be in a horizontal position. The height position of the motor support portion 111 is set in advance so that the height position of the motor support portion 111 can be finely adjusted to more accurately support the drive motor 69 in a horizontal posture. Will also be possible.

[0065]

As described above, according to the present invention, the belt tension applying device causes the drive motor to move against the frame member in a state where the tension of the endless belt and the urging force of the urging means are balanced. Since the fixing means for fixing is provided, the drive motor can exhibit high stability without displacing its position even during high-speed operation, and a state in which an appropriate tension as intended is obtained, It is possible to maintain the tension stably for a long time without changing the tension.

[Brief description of drawings]

FIG. 1 is an external perspective view of an apparatus main body of an inkjet printer according to the present invention.

FIG. 2 is an exploded perspective view of the apparatus body of the inkjet printer according to the present invention.

FIG. 3 is a side sectional view of the inkjet printer according to the present invention.

FIG. 4 is a front view of the apparatus main body of the inkjet printer according to the present invention.

FIG. 5 is a left side view of a transport unit that constitutes the inkjet printer according to the present invention.

FIG. 6 is an enlarged view of an end of a rotary shaft on the left side surface of the transport unit.

FIG. 7 is a perspective view of a power transmission device provided on the left side surface of the transport unit.

FIG. 8 is an external perspective view of a motor positioning device.

FIG. 9 is a side view of the motor positioning device.

10A is a view taken in the direction of the arrow y in FIG. 9, and FIG. 10B is a sectional view taken along line xx in FIG.

[Explanation of symbols]

1 Paper feeding unit 20 Carriage unit 22 carriage 24 inkjet recording head 40 encoder 50 power transmission device 51 endless belt 52 transmission gear 56 Shaft stop member 60 transport units 61 Transport unit frame 62 Transport drive roller 69 drive motor 69a drive shaft 69b Bearing part 70 pinion gear 71 tension coil spring 72 pin member 73 Spring hook 74 fixing screw 75 Guide hole 76 pin insertion hole 77 screw insertion hole 100 inkjet printer 101 Frame mounting plate 102 support plate 103, 104 holding block 105 Power supply connector 106 power switch 107 holding block 108 Push lever 110 Motor support means 111 Motor support 112 Base 113 Linear guide 114 Cylindrical member 115 Protective plate 200 Motor positioning device

Continued front page    F term (reference) 3F049 AA10 DA11 DA12 LA01 LB03                 3J049 AA03 AB03 BA03 BB14 BC03                       BH10 CA10

Claims (8)

[Claims] 1. A belt tension imparting device for imparting a predetermined tension to an endless belt which is engaged with a drive shaft of a drive motor and at least two or more rotating shafts, wherein the drive shaft is inserted through the endless belt. A guide hole extending in a frame member for mounting the drive motor, the guide motor being slidable in a tension increasing direction and a tension decreasing direction; and an urging means for urging the drive motor in the tension increasing direction. A belt tension imparting device, comprising: a fixing unit that fixes the drive motor to the frame member in a balance state between the tension of the endless belt and the urging force of the urging unit. 2. The structure according to claim 1, wherein the clearance between the outer circumference of the bearing portion of the drive shaft that slides on the inner circumference of the guide hole and the inner circumference of the guide hole is small. Belt tensioning device. 3. The driving means according to claim 1, wherein the fixing means is a screw insertion hole extending in the frame member in parallel with an extending direction of the guide hole, and the screw insertion hole is inserted into the screw insertion hole. The motor includes a screw hole formed in the motor and a fixing screw that is screwed into the motor, and the urging means includes a first spring retaining portion provided in the drive motor and a second spring retaining portion provided in the frame member. A belt tension applying device comprising a tension coil spring mounted between the spring retaining portion and the spring retaining portion. 4. The third spring retaining portion according to claim 3, wherein the first spring retaining portion is inserted into a pin insertion hole extending in the frame member in parallel with an extending direction of the guide hole, and is attached to a tip end portion. A belt tension imparting device, wherein the formed screw portion comprises a pin member screwed into a screw hole formed in the drive motor. 5. The belt tension applying device according to claim 4, wherein a clearance between the pin member and an inner circumference of the pin insertion hole is small. 6. The fixing means according to claim 4 or 5, wherein the pin member is screwed into a screw hole formed in the drive motor while pinching the frame member between the frame member and the precursor drive motor. A belt tension imparting device characterized by being configured to be used in combination. 7. The belt tension imparting device according to claim 1, wherein the drive motor is urged straight in the extending direction of the guide hole. 8. A recording unit for performing recording on a recording material, a conveyance drive roller for conveying the recording material to the recording unit at a constant pitch, and ejecting the recording material on which recording has been performed by the recording unit. A recording apparatus comprising: a paper discharge drive roller; and the drive motor according to any one of claims 1 to 7, which drives the transport drive roller and the paper discharge drive roller, The tension is applied to an endless belt that is rotated by a gear that rotates a roller, a gear that rotates the paper discharge drive roller, and a pinion gear provided on a drive shaft of the drive motor. A recording apparatus, comprising the belt tensioning device according to any one of 1 to 7.