JPH07266642A - Picture recording device - Google Patents

Abstract

PURPOSE:To shorten a total recording time from the that of recording to the end of discharging, by constituting a driving force transmitting system so as to be capable of driving a platen roller, a discharging roller and a cutter by a common driving motor. CONSTITUTION:A motor gear 21a is fixed to the rotary shaft of a driving motor 21 while a swinging member 25, transmitting selectively a driving force in accordance with the normal and reverse rotation of the motor 21, is attached to the same shaft Swinging gears 25b, 25c, meshed with the motor gear 21a, are attached to the free side of the swinging member 25 whereby a platen roller shaft 22 and a discharging roller shaft 23 are rotated by the rotation of the swinging gear 25c through gears 26a, 26b, 22c, 23c. On the other hand, a gear 22d, fixed to the rear side plate 24b side of the platen roller shaft 22, is meshed with a sector gear 27d and a crankarm 29 is swung by the rotation of the sector gear 27d through the crank shaft 28 formed on the sector gear 27d to operate a cutter arm 31 attached to the tip end of a connecting shaft 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus for recording an image on a roll-shaped recording sheet, cutting the recording sheet after recording into a predetermined length, and discharging the cut recording sheet to the outside of the apparatus. Regarding

[0002]

2. Description of the Related Art Conventionally, in an image recording apparatus mainly used in a facsimile machine, a recording sheet wound in a roll shape is conveyed by a platen roller, an image is recorded by a thermal head, and the recorded recording sheet is cut by a cutter. Is cut into a predetermined length, and the cut recording sheet is discharged to the outside of the apparatus by a discharge roller. Then, in order to eliminate waste of the recording sheet between the platen roller and the cutter, the leading edge of the recording sheet is returned to the position of the platen roller from the cutter after the cutting, and is used for the next recording.

Therefore, the image recording apparatus is provided with two drive motors, a platen motor for driving the platen roller and a discharge / cutter motor for driving the discharge roller and the cutter. The platen motor conveys and rewinds the recording sheet by the forward and reverse rotations thereof, and the discharge / cutter motor switches the drive transmission between the discharge roller and the cutter by using a one-way clutch or a swinging arm having a gear. ing.

The operation of the image recording apparatus configured as described above will be described with reference to FIG. During image recording by the thermal head, both motors are normally driven to convey the recording sheet by the platen roller and the discharge roller, and after the recording for one page is finished, the recording sheet is conveyed to the cutting position. Stop the motor once. Then, after the discharge / cutter motor is driven in reverse to cut the recording sheet by the cutter, the platen motor is driven in the reverse direction by a predetermined amount to rewind the leading end of the unrecorded recording sheet to the recording position. After the cutter has returned to the standby position and stopped,
The discharge / cutter motor is driven in the forward direction again to discharge the cut recording sheet to the outside of the apparatus by the discharge roller. When recording multiple pages, do not record the next page after the ejection of the previous page is finished, but start recording the next page at the same time when the ejection of the previous page is started, I try not to spend a lot of time.

[0005]

However, in the above-mentioned conventional example, since two drive motors are required, the cost is high, and more space for the drive motors must be secured inside the device. Therefore, there is a problem that the device becomes large. Further, during recording, it is necessary to rotate and drive the platen roller and the discharge roller in synchronization with each other, which causes a problem that synchronization and control of each motor becomes complicated. Further, in order to discharge the recording sheet of the final page, it is necessary to rotate the discharge / cutter motor again in the forward direction after the cutter returns to the standby position, which causes a problem that extra time is required.

Further, since the platen roller and the platen motor are directly connected by a gear or a timing belt and a pulley or the like, the driving force from the platen motor is transmitted to the platen roller by the same drive transmission system. The reduction ratio of the rotation of the platen roller with respect to the rotation of was only the same value in the forward rotation and the reverse rotation.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to reduce the cost of the apparatus, reduce the size and weight thereof, by using a minimum number of drive motors without providing a plurality of drive motors. In addition to simplifying the drive control of the drive motor and shortening the total recording time.

[0008]

A typical constitution of the present invention for achieving the above object is a platen roller for supporting and conveying a recording sheet, and recording for recording an image by pressing the recording sheet against the platen roller. An image recording apparatus comprising: a means, a cutter that cuts a recorded recording sheet into a predetermined length, and a discharge roller that discharges the cut recording sheet to the outside of the apparatus; A common drive motor that drives the roller and the cutter, a normal rotation drive force transmission unit that transmits the drive force of the drive motor during normal rotation to the platen roller and the discharge roller, and a drive force during reverse rotation of the drive motor. To the platen roller, the discharge roller, and the cutter, and a drive mechanism for selectively transmitting the driving force of the drive motor to each of the driving force transmitting means. A force transmission switching means is characterized by having a control means for controlling driving of the drive motor and the drive force transmission switching means.

[0009]

According to the present invention, since the driving force transmission system for driving the platen roller, the discharging roller and the cutter by the common driving motor is constituted, the platen roller and the discharging roller are driven by separate motors. The control of rotating the two rollers in synchronization with each other, which was necessary in some cases, becomes unnecessary. Further, since the platen roller, the discharge roller, and the cutter are driven by a common drive motor, it is possible to reduce the cost and size and weight of the device.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of an image recording apparatus to which the present invention is applied will be described below with reference to the drawings.

[First Embodiment] An image recording apparatus according to this embodiment is configured as a recording system of a facsimile apparatus, and is generally called a thermal recording apparatus. FIG. 7 is an explanatory view of the entire structure of the facsimile apparatus, and FIG. 8 is an external perspective view.

{Overall Configuration of Facsimile Apparatus} First, the overall configuration of the facsimile apparatus will be described with reference to FIGS. 7 and 8. This facsimile apparatus has a recording system A as a recording apparatus for recording on a roll-shaped heat-sensitive recording sheet S.
And a reading system B for reading the image written on the original G
And an operation unit C.

(Recording System) The recording system A records an image on the recording sheet S in accordance with an image signal transmitted from another device or an image signal transmitted from a reading system B described later. That is, the recording sheet S is conveyed by pressing the recording sheet S toward the platen roller 2 side by the thermal head 1 and drivingly rotating the platen roller 2 in the sheet conveying direction, and the thermal head 1 outputs an image signal in synchronization with the conveyance. In accordance with the above, heat is generated to form an image on the recording sheet S. Then, the recording sheet S on which a predetermined image is formed is further conveyed, cut by the cutter 3, and then discharged and conveyed to the sheet tray 6 outside the apparatus by the discharge roller 4 and the discharge roller 5. At the same time, the platen roller 2 is driven and rotated in the direction opposite to the sheet conveying direction to pull back the leading end of the unrecorded recording sheet S to the recording position to prepare for the next recording. The recording sheet S is guided by a guide shaft 7 so as not to hit the thermal head 1 before the platen roller 2.

(Reading System) On the other hand, the reading system B irradiates the original G with light and converts the reflected light into an electric signal, and transmits this signal to another machine according to the operation mode, or its own recording system. A
To be transmitted to. That is, a plurality of originals G set on the original placing table 11 are fed to the preliminary conveying roller 12a and the pressing piece 12.
In addition to being preliminarily conveyed by b, the separation roller 13a and the pressure contact piece 13b in pressure contact with the separation roller 13a separate and feed the originals G, and the original G is conveyed by the conveyance roller pairs 14a, 14b and the discharge roller pair 15a,
It is conveyed by 15b and discharged to the discharge tray 16. While the document G is being conveyed, image information is read by a photoelectric conversion element 17 such as a contact sensor, and the image signal is transmitted to its own recording system A in the copy mode, and is transmitted to another device in the transmission mode. To the recording system.

(Operation Unit) The operation unit C is a panel for performing operations such as the mode switching operation, the copy operation, and the transmission operation, and is provided with keys corresponding to various operations. The operation section C is provided above the reading system B and is rotatably supported with respect to the apparatus body. In addition, a handset (telephone) that performs transmission / reception on one end side of the operation unit C
Equipped with 18. Further, in the figure, 19 is an electrical equipment substrate, and 20 is a power supply unit.

{Structure of Driving System} Next, the structure of the driving system of the recording system A will be described in detail with reference to FIGS.
1 is a plan view showing the main components of the recording system A (excluding the thermal head 1 and the ejection roller 5), and FIG. 2 is a side view of the power transmission mechanism of the recording system A shown in FIG. Figure,
3 is a side view of the power transmission mechanism of the recording system A shown in FIG. 1 as seen from the direction of the arrow Y, FIG. 4 is a perspective view of the power transmission mechanism shown in FIG. 3, and FIG. 5 is an enlarged view of a sector gear. In this embodiment, all the gears in the figure have a module m = 0.5.

The recording system A according to the present invention, as shown in FIG. 1, has a platen roller 2, a cutter 3, and a discharge roller 4.
Is configured to be driven by only one common drive motor 21. The drive motor 21 is fixed to a frame (not shown) of the apparatus main body, and a motor gear 21a (the number of teeth Z = 17) is attached to its shaft. The platen roller 2 and the discharge roller 4 are respectively the platen roller shaft 2
2, the discharge roller shaft 23 is attached to these shafts 2
Reference numerals 2 and 23 are attached to a front side plate 24a and a rear side plate 24b which form a part of the frame of the apparatus main body through bearings 22a and 22b and bearings 23a and 23b.

The structure of each driving force transmitting means for transmitting the driving force of the driving motor 21 to the platen roller 2, the cutter 3 and the discharge roller 4 will be described below.

(First Driving Force Transmission Means and Second Driving Force Transmission Means) As shown in FIGS. 1 and 2A, the drive motor 21
As described above, the motor gear 21a (the number of teeth Z
= 17) is fixed, and a swinging member 25 for selectively transmitting a driving force according to the forward / reverse rotation of the motor 21 is attached. A shaft 25a rotatably attached to an end of the swing member 25 has a first swing gear 25b (the number of teeth Z which is arranged so as to always mesh with the motor gear 21a).
= 61) and the second swing gear 25c with a large tooth width (number of teeth Z = 2
4) is attached. The second oscillating gear 25c has gears 26a and 26b of the same shape, which are rotatably attached to shafts 26 fixed to the front side plate 24a (number of teeth Z = 61).
Are arranged so as to mesh with each other at the same time. Further the gear
The gear 26a is arranged to mesh with a gear 22c attached to the platen roller shaft 22, and the gear 26b is arranged to mesh with a gear 23c attached to the discharge roller shaft 23.

The reduction ratio R _p of the platen roller 2 with respect to the drive motor 21 by the drive force transmission means having the above structure
Is R _p = (Z _25b / Z _21a ) × (Z _26a / Z _25c ) × (Z
The _{22c / Z 26a) = (61/17} ) × (61/24) × (61/61) ≒ 9.120.

(Third Driving Force Transmission Means, Fourth Driving Force Transmission Means, and Fifth Driving Force Transmission Means) In FIG. 1, 27 is a driving force transmission shaft, which is connected to the front side plate 24a via bearings 27a and 27b. Rear plate
It is attached across 24b. Driving force transmission shaft 27
A gear 27c (the number of teeth Z = 61) is fixed to the front side plate 24a side, and the second swing gear 25c meshes when the swing member 25 moves to the position shown in FIG. 2 (b). Are arranged as follows. Similarly, as shown in FIG. 3, a sector gear 27d with teeth cut off is fixed to the rear side plate 24b as shown in FIG.

As shown in FIG. 5, the sector gear 27d is a gear formed by leaving 20 teeth shown in the figure from a gear having a module m = 0.5 and the number of teeth Z = 61. The sector gear 27d is a gear in which the 20 teeth are fixed to the rear side plate 24b of the platen roller shaft 22 during one rotation.
It is arranged so as to mesh with 22d (the number of teeth Z = 61).

A crank shaft 28 is formed on the sector gear 27d at a position (about 10 mm in this embodiment) apart from the center of rotation by a predetermined amount. A crank arm 29 is attached to the crank shaft 28, and the tip of the crank arm 29 is attached to the connecting shaft 30.
It is connected to the cutter arm 31 via. The cutter 3 is connected to the cutter arm 31.

Here, the structure of the cutter 3 in this embodiment will be described. As shown in FIG. 4, the cutter 3 includes an upper blade 3a and a lower blade 3b. A torsion coil spring 3d is applied to a rotary shaft 3c provided at the end of the upper blade 3a,
Its tip is rotatably supported by the cutter side plate 3e. The upper blade 3a is pressed by the torsion coil spring 3d so as to rotate in the clockwise direction. Further, a stopper 3f is integrally formed at the end of the upper blade 3a, and the stopper 3f hits the lower blade 3b to stop the rotation of the upper blade 3a. A rotary shaft 3g provided at the end of the lower blade 3b is rotatably supported by the cutter side plate 3e, and its tip is fitted into the cutter arm 31. Further, a connecting shaft 3h is provided at the end of the lower blade 3b, and the connecting shaft 3h is fitted into the cutter arm 31 through an elongated hole 3i formed in the cutter side plate 3e. A cutter home position detection sensor (not shown) such as a micro switch is provided below the cutter arm 31 to detect whether the cutter 3 is in the standby position or the cutting position.

Further, as shown in FIGS. 3 and 4, the rear side plate
The gear 22d fixed to the platen roller shaft 22 on the 24b side is
It meshes with a gear 32a (the number of teeth Z = 38) rotatably attached to a shaft 32 fixed to the rear side plate 24b, and the gear 32a is rotatably attached to a shaft 33 fixed to the rear side plate 24b. Gear 33a (the number of teeth Z = 38). The gear 33a is provided on the rear plate 24 of the discharge roller shaft 23.
It meshes with a gear 23d (number of teeth Z = 24) attached to the b side. A one-way clutch 23e for transmitting the driving force only in one direction is built in the center of the gear 23d.

With the driving force transmitting means having the above structure, the drive motor when the gear 33d and the sector gear 27d mesh with each other.
The reduction ratio R _p ′ of the platen roller 2 with respect to 21 is R _p ′ = (Z _25b / Z _21a ) × (Z _27c / Z _25c ) ×
(Z _22d / Z _27d ) = (61/17) x (61/24) x (61/61) = 9.120.

Therefore, the speed reduction ratio R _p by the driving force transmission means at the time of the normal rotation of the drive motor and the speed reduction ratio R _p ′ by the driving force transmission means at the time of the reverse rotation of the drive motor are equal. That is,
The number of teeth of each gear of the driving force transmission means is set so that the reduction ratios are equal.

The driving force transmission shaft of the sector gear 27d
The positional relationship between the attachment to the 27 and the crankshaft 28 is such that the state shown in FIG. 3A is obtained when the cutter 3 is at the standby position.

{Operation of Driving System} Next, the operation of the driving system of the recording system A will be described with reference to FIGS.

(Operation at the time of normal rotation of the drive motor) First, the operation when the drive motor 21 rotates normally and the motor gear 21a rotates in the direction of arrow a will be described. As shown in FIG. 2A, when the motor gear 21a rotates in the arrow a direction, the first swing gear 25b swings while rotating in the arrow a direction, and at the same time, the second swing gear 25c moves in the arrow a direction. Rotating and rocking gear
It meshes with 26a and 26b. Thereby, the drive motor 21
Driving force is transmitted, the gear 22c fixed to the platen roller shaft 22 rotates in the direction of arrow c via the gear 26a, and the gear 23c fixed to the discharge roller shaft 23 moves in the direction of arrow d via the gear 26b. Rotate. That is, the normal rotation driving force of the drive motor 21 causes the platen roller 2 and the discharge roller 4 to rotate in the direction in which the recording sheet is conveyed.

Further, as the platen roller 2 and the discharge roller 4 rotate in the conveying direction of the recording sheet respectively, the gear 22d fixed to the rear side plate 24b of the platen roller shaft 22 rotates in the direction of arrow c, The gear 23d rotates in the arrow d'direction via the gears 32a and 33a. At this time,
Although the discharge roller shaft 23 rotates in the direction of arrow d, the one-way clutch 23 that transmits the driving force only in one direction (in this embodiment, the direction of arrow d) is interposed between the discharge roller shaft 23 and the gear 23d. The rotation of the gear 23d in the direction of the arrow d'is not transmitted to the discharge roller shaft 23.

As described above, when the drive motor 21 rotates in the direction of arrow a (normal rotation), the platen roller 2
The discharge roller 4 rotates in the direction of conveying the recording sheet, and the thermal head 1 records a predetermined image while conveying the sheet.

Here, when the transport amount when the platen roller 2 and the discharge roller 4 transport the recording sheet and the respective roller diameters are calculated, the reduction ratio R when the platen roller 2 rotates in the forward direction is calculated. _p is R _p ≈9.120, as calculated previously.

Similarly, the reduction ratio R _h when the discharge roller 4 rotates normally is R _h = (Z _25b / Z _21a ) × (Z _26b / Z _25c ) × (Z
The _{23c / Z 26b) = (61/17} ) × (61/24) × (43/61) ≒ 6.429.

The facsimile apparatus of this embodiment is a GIV facsimile, and the recording resolution in the recording sheet conveying direction (sub-scanning direction) is 400 dpi (dots / inch). Therefore, the length L ₀ of one dot in the sub-scanning direction is L ₀ = 25.4 / 400 = 0.0635 (mm).

The drive motor 21 has a step angle of 7.5 °,
Since it is a 2-phase PM type stepping motor and is operated by 1-2 phase drive, the minimum step angle θ ₀ when the drive motor 21 rotates is θ ₀ = 7.5 ° / 2 = 3.75 °.

Therefore, the diameter d _p of the platen roller 2 is
The minimum step angle θ _p0 (rad) of the platen roller 2 is obtained by the following equation.

L ₀ = (d _p / 2) × θ _p0

Here, θ _p0 = (θ ₀ × π / 180 °) R _p ∴d _p = 2 × L ₀ / θ _p0 = {2 × L ₀ / (θ ₀ × π / 180 °)} × R _p ≈ 17.697 (mm).

However, when the diameter d _p of the platen roller 2 is actually manufactured to have this size and an image is recorded, the surface of the platen roller 2 is deformed and the load for conveying the recording sheet causes the recording sheet to move. The carry amount decreases, and the image shrinks. Therefore, the design value of the diameter d _p of the platen roller 2 is set to a value slightly larger than the calculated value, and is determined as follows.

D _p = 17.90 ± 0.05 (mm)

During image recording, the drive motor 21 is set to 40
Since the driving is performed at 0 pps (pulses / sec), the length L ₁ that the recording sheet is conveyed by the platen roller 2 in one second is as follows assuming that the image does not expand or contract.

L ₁ = L ₀ × 400 = 25.40 (mm)

Thus, in order to prevent the recording sheet from being bent between the platen roller 2 and the discharge roller 4, the platen roller 2 conveys the length for which the discharge roller 4 conveys the recording sheet for one second. Slightly larger than the length,
When set to 25.42 (mm), the diameter d _{h of the} discharge roller 4
And the discharge roller angular rotation speed ω _h are as follows.

D _h / 2 × ω _h = 25.42

Here, the discharge roller angular rotation speed ω _h is ω _h = (3.75 ° × 400 × π / 180 °) / R _h ≈4.0722 (rad / s).

Therefore, d _h ≈12.4846 (mm).

The design value of the diameter d _h of the discharge roller 4 is set to a value slightly larger than the calculated value as in the case of the platen roller 2, and d _h = 12.70 ± 0.05 (mm).

(Operation when the drive motor reversely rotates) Next, the operation when the drive motor 21 reversely rotates and the motor gear 21a rotates in the direction of arrow a'will be described. As shown in FIG. 2B, when the motor gear 21a rotates in the direction of arrow a ', the first swing gear 25b and the second swing gear 25c swing while rotating in the direction of arrow a', and The swing gear 25c meshes with the gear 27c. As a result, the drive force of the drive motor 21 is transmitted, and the gear 27c fixed to the drive force transmission shaft 27 rotates in the arrow b'direction.

The rear side plate 24b of the driving force transmission shaft 27
The sector gear 27d fixed to the side rotates in the arrow b'direction, and at the same time, the crankshaft 28 provided on the sector gear 27d rotates in the arrow b'direction around the driving force transmission shaft 27. As a result, the reverse driving force of the drive motor 21 is transmitted to the cutter 4 via the crank arm 29 and the cutter arm 31. That is, the arrow b'of the crankshaft 28
By the rotation in the direction, the crank arm 29 and the cutter arm 31 move from the position shown in FIG. 3 (a) to the position shown in FIG. 3 (b), and the cutter 3 moves from the standby position to the cutting position. The trailing edge of the recording sheet on which predetermined recording has been performed is cut.

While the cutter 3 is moving from the standby position to the cutting position, the gear portion of the sector gear 27d does not mesh with the gear 33d as shown in FIG. 3B, so the platen roller 2 The driving force is not transmitted to the discharge roller 4, and is similarly not transmitted to the discharge roller 4. That is, the recording sheet is cut while the platen roller 2 and the discharge roller 4 are stopped.

When the sector gear 27d further rotates in the direction of arrow b'from the state shown in FIG. 3B, the state shown in FIG.
As shown in (c), the gear portion of the sector gear 27d meshes with the gear 22d fixed to the platen roller shaft 22, and the gear 22d rotates in the direction of arrow c '. As a result, the platen roller 2 rotates in the direction opposite to the sheet conveying direction, and the unrecorded recording sheet sandwiched between the roller 2 and the thermal head 1 is rewound. Further, the rotation of the gear 22d in the direction of the arrow c'through the gears 32a and 33a,
23d rotates in the direction of arrow d, and the discharge roller shaft 23 rotates in the direction of arrow d by the action of the one-way clutch 23e described above. As a result, the discharge roller 4 rotates in the sheet conveying direction, and the recording sheet, on which the predetermined recording is performed and the rear end side is cut, is discharged and conveyed onto the sheet tray 6 outside the apparatus by the discharge roller 4 and the discharge roller 5. That is, the operation of rewinding the leading end of the unrecorded recording sheet to the recording position and the recording sheet on which the predetermined recording is performed and the trailing end side is cut off
The operation of discharging upward is performed at the same time.

On the other hand, while the gear portion of the sector gear 27d and the gear 22d fixed to the platen roller shaft 22 are engaged, the gear 22c fixed to the front side plate 24a side of the platen roller shaft 22 is in the direction of arrow c '. The gear 26a that rotates and meshes with the gear 22c rotates in the direction of arrow e '. At the same time, a gear 23c fixed to the front plate side 24a of the discharge roller shaft 23
Rotates in the direction of arrow d, and the gear 26 meshes with the gear 23c.
b rotates in the direction of arrow e. However, the gear 26
Since a and 26b are independently rotatably attached to the shaft 26, there is no problem even if they rotate in opposite directions.

When the sector gear 27d further rotates in the direction of arrow b'from the state shown in FIG. 3C, the state shown in FIG.
As shown in (a), the meshed state of the gear portion of the sector gear 27d and the gear 22d is released, and the gear 22d stops rotating. As a result, the platen roller 2 and the discharge roller 4 stop rotating. At this time, the leading edge of the unrecorded recording sheet is rewound by about 2 mm from the recording position to the position of the cutter 3, and the recording sheet on which the predetermined recording is performed and the trailing edge is cut is completely discharged onto the sheet tray 6. Has been done. The rewinding amount of the recording sheet by the platen roller 2 is set by the number of teeth of the sector gear 27d and the distance relationship from the recording position to the cutting position. In this embodiment, the sector gear is
The number of teeth of 32d is 20, and the distance from the recording position to the cutting position is set to 20.4 mm. In addition, the discharge roller 3
Since the discharging amount of the recording sheet according to (4) needs to be larger than the distance from the cutting position to the discharging position, the number of teeth of the gears 32a, 33a, 23d is set in consideration of this, and in this embodiment, it is confirmed by the calculation described later. As described above, the distance is set to 24 mm.

Then, as shown in FIG.
When the cutter home position detection sensor (not shown) detects that the cutter 3 is at the standby position after the meshed state of 27d and 22d is released, the drive motor 21 stops rotating. When further recording is required, the motor is driven again and the above-described operation is repeated.

As described above, when the drive motor 21 rotates (reverses) in the direction of the arrow a ', the cutter 4 drives to cut the recording sheet, and after the cutting, the platen roller 2 moves in the sheet conveying direction. Rotates in the opposite direction to rewind the recording sheet, and at the same time, the discharge roller 4 rotates in the sheet conveying direction to discharge and convey the recording sheet.

In this embodiment, as described above, each drive transmission system is set so that the reduction ratio of the platen roller 2 with respect to the drive motor 21 is the same regardless of the forward / reverse rotation thereof. It is not limited to this. For example, when the number of teeth of the gear 27c forming the drive transmission system during reverse rotation of the platen roller 2 is changed from 61 to 55, the reduction ratio R _p ″ of the platen roller 24 during reverse rotation of the drive motor is R _p ″ = ( Z _25b / Z _21a ) x (Z _27c / Z _25c ) x
(Z _22d / Z _27d ) = (61/17) x (55/24) x (61/61) = 8.223. Therefore, the relationship of the reduction ratio is R _p ″ <R _p. Therefore, when the rotation speed of the drive motor 21 is the same, the platen roller 2 is more rewound during sheet rewinding than during sheet conveyance.
It turns out that the rotation speed of is fast. That is, the sheet rewinding time can be shortened by making the reduction ratio of the platen roller 2 at the time of reverse rotation of the drive motor smaller than the reduction ratio of the platen roller 2 at the time of normal rotation of the drive motor. A drive system can be realized.

Here, the rewinding amount of the recording sheet of the platen roller 2 in this embodiment is calculated. Sector gear 27
When d rotates once, the number of teeth meshing with the gear 22d (the number of teeth Z = 61) fixed to the platen roller shaft 22 is 20, so the rotation amount of the platen roller 2 is 20/61 rotations. Therefore, the rewound amount δ _p of the recording sheet by the platen roller 2 is δ _p = π · d _p × (22/61) ≈18.438 (mm).

The margin 2 mm of the margin of the head of the recording sheet is added to the above numerical values so that the distance from the recording position on the platen roller 2 to the cutting position of the cutter 3 is 20.4 mm, and the platen roller 2 and the cutter 3 Set the positional relationship of.

Next, the discharge / conveyance amount of the recording sheet by the discharge roller 4 in this embodiment is calculated. The rotation speed ratio R _ph of the discharge roller 4 to the platen roller 2 when the drive motor 21 is driven in the reverse direction is R _ph = (Z _32a / Z _22d ) × (Z _33a / Z _32a ) × (Z
_23d / Z _33a ) = (38/61) x (38/38) x (24/38) = 0.3934.

Therefore, the gear portion and the gear of the sector gear 27d are
The rotation amount of the discharge roller 4 when the 22d is meshed is 20/61 / R _ph ≈0.8333.

Therefore, the discharge conveyance amount δ _h of the recording sheet by the discharge roller 2 at this time is δ _h = 0.8333 × π · d _h ≈33.249 (mm).

In this embodiment, the distance from the recording sheet cutting position of the cutter 3 to the discharge roller 4 is set to 24 mm, so that the discharge roller 2 can completely discharge and convey the recording sheet.

The operation of the recording system A described above is shown in the timing chart of FIG. As is clear from comparison with the timing chart of FIG. 16 described in the conventional example, since there is only one drive motor for driving the recording system, it is necessary to move the two drive motors in synchronization as in the conventional example. There is no. Further, since the recording operation for one page only rotates the drive motor in the forward direction and the reverse direction, the drive control of the motor is simple. Further, the time required for the recording operation is shortened.

[Second Embodiment] Next, a second embodiment of the image recording apparatus to which the present invention is applied will be described with reference to the drawings. The image recording apparatus according to the present embodiment is also configured as a recording system of a facsimile apparatus in the same manner as the above-described embodiment, and is generally called a thermal recording apparatus. The members having the same functions and configurations as those of the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

{Structure of Drive System} The drive system of the recording system, which is a feature of this embodiment, will be described in detail below. FIG. 9 is a top plan view of the drive system of the image recording apparatus according to the present embodiment, and FIG.
FIG. 10 is a side view of the drive system shown in FIG. 9 viewed from the direction of arrow X. In this embodiment, all the gears in the figure have a module m = 0.5.

Similarly to the above-described embodiment, the recording system A according to the present invention drives the platen roller 2, the cutter 3, and the discharge roller 4 by only one common drive motor 21, as shown in FIG. Is configured as follows. The drive motor 21
Is fixed to a frame (not shown) of the apparatus main body, and a motor gear 21a (the number of teeth Z = 17) is attached to its shaft. The platen roller 2 and the discharge roller 4 are attached to a platen roller shaft 22 and a discharge roller shaft 23, respectively, and these shafts 22 and 23 are bearings 22a and 22b and bearings.
It is attached to a front side plate 24a and a rear side plate 24b which constitute a part of the frame of the apparatus main body via 23a and 23b.

The structure of each driving force transmitting means for transmitting the driving force of the driving motor 21 to the platen roller 2, the cutter 3 and the discharging roller 4 will be described below.

(First Driving Force Transmission Means and Second Driving Force Transmission Means) As shown in FIGS. 9 and 10 (a), the drive motor 21
As described above, the motor gear 21a (the number of teeth Z
= 17) is fixed, and a swinging member 25 for selectively transmitting a driving force according to the forward / reverse rotation of the motor 21 is attached. A shaft 25a rotatably attached to an end of the swing member 25 has a first swing gear 25b (the number of teeth Z which is arranged so as to always mesh with the motor gear 21a).
= 61), the second swing gear 25c (the number of teeth Z = 2), which is arranged so that it can selectively mesh with the gear 22c attached to the platen roller shaft 22 and other gears described later.
4) is attached.

Incidentally, the reduction ratio R _p of the platen roller 2 with respect to the drive motor 21 by the drive force transmission means having the above structure
Is R _p = (Z _25b / Z _21a ) × (Z _22c / Z _25c ) = (61/17) × (61/24) ≈9.120.

The gear 22c attached to the platen roller shaft 22 meshes with a gear 26c (the number of teeth Z = 38) rotatably attached to a shaft 26 fixed to the front side plate 24a, and further the gear 26c. Is arranged so as to mesh with a gear 23c (number of teeth Z = 43) attached to the discharge roller shaft 23. A one-way clutch 23f for transmitting the driving force in only one direction is built in the center of the gear 23c.

(Third Driving Force Transmission Means, Fourth Driving Force Transmission Means, and Fifth Driving Force Transmission Means) In FIG. 9, 27 is a driving force transmission shaft, which is connected to the front side plate 24a via bearings 27a and 27b. Rear plate
It is attached across 24b. Driving force transmission shaft 27
A gear 27c (the number of teeth Z = 61) is fixed to the side of the front plate 24a, and meshes with a gear 34a (the number of teeth Z = 61) rotatably attached to the shaft 34 fixed to the front plate 24a. Are arranged as follows. Further, the gear 34a is connected to the swing member 25.
Is arranged so that it can mesh with the second swing gear 25c when it moves to the position shown in FIG. 10 (b). Further, a sector gear 27d having teeth cut off at a part of its outer periphery is fixed to the rear plate 24b side of the driving force transmission shaft 27.

As shown in FIG. 5, the sector gear 27d is a gear formed by leaving 20 teeth shown in the drawing from a gear having a module m = 0.5 and the number of teeth Z = 61. The sector gear 27d is a gear in which the 20 teeth are fixed to the rear side plate 24b of the platen roller shaft 22 during one rotation.
It is arranged so as to mesh with 22d (the number of teeth Z = 61).

A crankshaft 28 is formed on the sector gear 27d at a position (about 10 mm in this embodiment) apart from the center of rotation by a predetermined amount. A crank arm 29 is attached to the crank shaft 28, and the tip of the crank arm 29 is attached to the connecting shaft 30.
It is connected to the cutter arm 31 via. The cutter 3 is connected to the cutter arm 31.

Now, the structure of the cutter 3 in this embodiment will be described. As shown in FIG. 4, the cutter 3 includes an upper blade 3a and a lower blade 3b. A torsion coil spring 3d is applied to a rotary shaft 3c provided at the end of the upper blade 3a,
Its tip is rotatably supported by the cutter side plate 3e. The upper blade 3a is pressed by the torsion coil spring 3d so as to rotate in the clockwise direction. Further, a stopper 3f is integrally formed at the end of the upper blade 3a, and the stopper 3f hits the lower blade 3b to stop the rotation of the upper blade 3a. A rotary shaft 3g provided at the end of the lower blade 3b is rotatably supported by the cutter side plate 3e, and its tip is fitted into the cutter arm 31. Further, a connecting shaft 3h is provided at the end of the lower blade 3b, and the connecting shaft 3h is fitted into the cutter arm 31 through an elongated hole 3i formed in the cutter side plate 3e. A cutter home position detection sensor (not shown) such as a micro switch is provided below the cutter arm 31 to detect whether the cutter 3 is in the standby position or the cutting position.

As shown in FIGS. 3 and 4, the rear side plate
The gear 22d fixed to the platen roller shaft 22 on the 24b side is
It meshes with a gear 32a (the number of teeth Z = 38) rotatably attached to a shaft 32 fixed to the rear side plate 24b, and the gear 32a is rotatably attached to a shaft 33 fixed to the rear side plate 24b. Gear 33a (the number of teeth Z = 38). The gear 33a is provided on the rear plate 24 of the discharge roller shaft 23.
It meshes with a gear 23d (number of teeth Z = 24) attached to the b side. A one-way clutch 23e for transmitting the driving force only in one direction is built in the center of the gear 23d.

With the driving force transmitting means having the above structure, the drive motor when the gear 33d and the sector gear 27d mesh with each other.
The reduction ratio R _p ′ of the platen roller 2 with respect to 21 is R _p ′ = (Z _25b / Z _21a ) × (Z _34a / Z _25c ) ×
The _{(Z 27c / Z 34a) ×} (Z 22d / Z 27d) = (61/17) × (61/24) × (61/61) × (61/61) ≒ 9.120.

Therefore, the speed reduction ratio R _p by the driving force transmission means at the time of the normal rotation of the drive motor and the speed reduction ratio R _p ′ by the driving force transmission means at the time of the reverse rotation of the drive motor are equal. That is,
The number of teeth of each gear of the driving force transmission means is set so that the reduction ratios are equal.

The driving force transmission shaft of the sector gear 27d
As for the positional relationship between the mounting method of the crankshaft 28 and the crankshaft 28, as in the above-described embodiment, when the cutter 3 is at the standby position, it is set so as to be in the state shown in FIG.

{Operation of Driving System} Next, the operation of the driving system of the recording system according to this embodiment will be described with reference to FIGS. 9, 10 and 3.

(Operation at Normal Rotation of Drive Motor) First, the operation when the drive motor 21 rotates in the forward direction and the motor gear 21a rotates in the direction of arrow a will be described. As shown in FIG. 10 (a), when the motor gear 21a rotates in the arrow a direction, the first swing gear 25b swings while rotating in the arrow a direction, and at the same time, the second swing gear 25c moves in the arrow a direction. It oscillates while rotating and meshes with a gear 22c fixed to the platen roller shaft 22. As a result, the driving force from the drive motor 21 is transmitted, and the gear 22c fixed to the platen roller shaft 22 rotates in the direction of arrow c. Further, the driving force of the drive motor 21 is equal to that of the gear 22.
It is transmitted to a gear 23c fixed to the discharge roller shaft 23 via a gear 26c meshing with c, and the gear 23c is indicated by an arrow d.
Rotate in the direction. Since the gear 23c has a built-in one-way clutch 23f that transmits the rotation in the direction of the arrow d to the roller shaft 23, the roller shaft 23 rotates in the same direction as the gear 23c. That is, the normal rotation driving force of the drive motor 21 causes the platen roller 2 and the discharge roller 4 to rotate in the direction in which the recording sheet is conveyed.

Further, as the platen roller 2 and the discharge roller 4 rotate in the conveying direction of the recording sheet respectively, the gear 22d fixed to the rear plate 24b side of the platen roller shaft 22 rotates in the direction of arrow c, The gear 23d rotates in the arrow d'direction via the gears 32a and 33a. At this time,
Although the discharge roller shaft 23 rotates in the direction of arrow d, the one-way clutch 23 that transmits the driving force only in one direction (in this embodiment, the direction of arrow d) is interposed between the discharge roller shaft 23 and the gear 23d. The rotation of the gear 23d in the direction of the arrow d'is not transmitted to the discharge roller shaft 23.

As described above, when the drive motor 21 rotates in the direction of arrow a (normal rotation), the platen roller 2
The discharge roller 4 rotates in the direction of conveying the recording sheet, and the thermal head 1 records a predetermined image while conveying the sheet.

Here, when the conveyance amount when the platen roller 2 and the discharge roller 4 convey the recording sheet and the respective roller diameters are calculated, the reduction ratio R when the platen roller 2 rotates in the forward direction is calculated. _p is R _p ≈9.120, as calculated previously.

Similarly, the speed reduction ratio R _h when the discharge roller 4 rotates normally is R _h = (Z _25b / Z _21a ) × (Z _22c / Z _25c ) × (Z
The _{26c / Z 22c) × (Z} 23c / Z 26c) = (61/17) × (61/24) × (38/61) × (43/38) ≒ 6.429.

The facsimile apparatus of this embodiment is a GIV facsimile machine, and the recording resolution in the sheet conveying direction (sub-scanning direction) is 400 dpi (dots / inch). Therefore, the length L ₀ of one dot in the sub-scanning direction is L ₀ = 25.4 / 400 = 0.0635 (mm).

The drive motor 21 has a step angle of 7.5 °,
Since it is a 2-phase PM type stepping motor and is operated by 1-2 phase drive, the minimum step angle θ ₀ when the drive motor 21 rotates is θ ₀ = 7.5 ° / 2 = 3.75 °.

Therefore, the diameter d _p of the platen roller 2 is
The minimum step angle θ _p0 (rad) of the platen roller 2 is obtained by the following equation.

L ₀ = (d _p / 2) × θ _p0

Here, θ _p0 = (θ ₀ × π / 180 °) R _p ∴d _p = 2 × L ₀ / θ _p0 = {2 × L ₀ / (θ ₀ × π / 180 °)} × R _p ≈ 17.697 (mm).

However, when the diameter d _p of the platen roller 2 is actually manufactured to have this size and an image is recorded, the surface of the platen roller 2 is deformed and the load for conveying the recording sheet causes the recording sheet to move. The carry amount decreases, and the image shrinks. Therefore, the design value of the diameter d _p of the platen roller 2 is set to a value slightly larger than the calculated value, and is determined as follows.

D _p = 17.90 ± 0.05 (mm)

At the time of image recording, the drive motor 21 is set to 40
Since the driving is performed at 0 pps (pulses / sec), the length L ₁ that the recording sheet is conveyed by the platen roller 2 in one second is as follows assuming that the image does not expand or contract.

L ₁ = L ₀ × 400 = 25.40 (mm)

Thus, in order to prevent the recording sheet from being bent between the platen roller 2 and the discharge roller 4, the platen roller 2 conveys the length for which the discharge roller 4 conveys the recording sheet in one second. Slightly larger than the length,
When set to 25.42 (mm), the diameter d _{h of the} discharge roller 4
And the discharge roller angular rotation speed ω _h are as follows.

D _h / 2 × ω _h = 25.42

Here, the discharge roller angular rotation speed ω _h is ω _h = (3.75 ° × 400 × π / 180 °) / R _h ≈4.0722 (rad / s).

Therefore, d _h ≈12.4846 (mm).

As with the platen roller 2, the design value of the diameter d _h of the discharge roller 4 is also slightly larger than the calculated value, and d _h = 12.70 ± 0.05 (mm).

(Operation when the drive motor reversely rotates) Next, the operation when the drive motor 21 reversely rotates and the motor gear 21a rotates in the arrow a'direction will be described. As shown in FIG. 10 (b), when the motor gear 21a rotates in the direction of arrow a ', the first swing gear 25b and the second swing gear 25c swing while rotating in the direction of arrow a', and The swing gear 25c meshes with the gear 34a. As a result, the drive force of the drive motor 21 is transmitted, and the gear 27c fixed to the drive force transmission shaft 27 via the gear 34a rotates in the direction of arrow b '.

Then, the rear side plate 24b of the driving force transmitting shaft 27
The sector gear 27d fixed to the side rotates in the arrow b'direction, and at the same time, the crankshaft 28 provided on the sector gear 27d rotates in the arrow b'direction around the driving force transmission shaft 27. As a result, the reverse driving force of the drive motor 21 is transmitted to the cutter 4 via the crank arm 29 and the cutter arm 31. That is, the arrow b'of the crankshaft 28
By the rotation in the direction, the crank arm 29 and the cutter arm 31 move from the position shown in FIG. 3 (a) to the position shown in FIG. 3 (b), and the cutter 3 moves from the standby position to the cutting position. The trailing edge of the recording sheet on which predetermined recording has been performed is cut.

It should be noted that while the cutter 3 is moving from the standby position to the cutting position, the gear portion of the sector gear 27d does not mesh with the gear 33d as shown in FIG. 3B, so that the platen roller 2 The driving force is not transmitted to the discharge roller 4, and is similarly not transmitted to the discharge roller 4. That is, the recording sheet is cut while the platen roller 2 and the discharge roller 4 are stopped.

When the sector gear 27d further rotates in the direction of arrow b'from the state shown in FIG. 3B, the state shown in FIG.
As shown in (c), the gear portion of the sector gear 27d meshes with the gear 22d fixed to the platen roller shaft 22, and the gear 22d rotates in the direction of arrow c '. As a result, the platen roller 2 rotates in the direction opposite to the sheet conveying direction, and the unrecorded recording sheet sandwiched between the roller 2 and the thermal head 1 is rewound. Further, the rotation of the gear 22d in the direction of the arrow c'through the gears 32a and 33a,
23d rotates in the direction of arrow d, and the discharge roller shaft 23 rotates in the direction of arrow d by the action of the one-way clutch 23e described above. As a result, the discharge roller 4 rotates in the sheet conveying direction, and the recording sheet, on which the predetermined recording is performed and the rear end side is cut, is discharged and conveyed onto the sheet tray 6 outside the apparatus by the discharge roller 4 and the discharge roller 5. That is, the operation of rewinding the leading end of the unrecorded recording sheet to the recording position and the recording sheet on which the predetermined recording is performed and the trailing end side is cut are set in the sheet tray 6.
The operation of discharging upward is performed at the same time.

On the other hand, while the gear portion of the sector gear 27d and the gear 22d fixed to the platen roller shaft 22 mesh with each other, the gear 22c fixed to the front side plate 24a side of the platen roller shaft 22 moves in the direction of arrow c '. Rotate. As a result, the gear 23c fixed to the front plate 24a side of the discharge roller shaft 23 via the gear 26c rotates in the direction of arrow d '. At this time, the roller shaft 23 is moved to the arrow d by the driving force transmission on the rear plate 24b side.
Is rotating in the direction. However, since the gear 23c incorporates the one-way clutch 23f that transmits only the rotation in the direction of the arrow d to the roller shaft 23, as described above,
There is no problem if they rotate in opposite directions.

When the sector gear 27d further rotates in the direction of arrow b'from the state shown in FIG. 3C, the state shown in FIG.
As shown in (a), the meshed state of the gear portion of the sector gear 27d and the gear 22d is released, and the gear 22d stops rotating. As a result, the platen roller 2 and the discharge roller 4 stop rotating. At this time, the leading edge of the unrecorded recording sheet is rewound by about 2 mm from the recording position to the position of the cutter 3, and the recording sheet on which the predetermined recording is performed and the trailing edge is cut is completely discharged onto the sheet tray 6. Has been done. The rewinding amount of the recording sheet by the platen roller 2 is set by the number of teeth of the sector gear 27d and the distance relationship from the recording position to the cutting position. In this embodiment, the sector gear is
The number of teeth of 32d is 20, and the distance from the recording position to the cutting position is set to 20.4 mm. In addition, the discharge roller 3
Since the discharging amount of the recording sheet according to (4) needs to be larger than the distance from the cutting position to the discharging position, the number of teeth of the gears 32a, 33a, 23d is set in consideration of this, and in this embodiment, it is confirmed by the calculation described later. As described above, the distance is set to 24 mm.

Then, as shown in FIG.
When the cutter home position detection sensor (not shown) detects that the cutter 3 is at the standby position after the meshed state of 27d and 22d is released, the drive motor 21 stops rotating. When further recording is required, the motor is driven again and the above-described operation is repeated.

As described above, when the drive motor 21 rotates (reverses) in the direction of the arrow a ', the cutter 4 drives to cut the recording sheet, and after the cutting, the platen roller 2 moves in the sheet conveying direction. Rotates in the opposite direction to rewind the recording sheet, and at the same time, the discharge roller 4 rotates in the sheet conveying direction to discharge and convey the recording sheet.

In this embodiment, as described above, each drive transmission system is set so that the speed reduction ratio of the platen roller 2 with respect to the drive motor 21 is equal irrespective of its forward and reverse rotation. It is not limited to this. For example, when the number of teeth of the gear 27c forming the drive transmission system during reverse rotation of the platen roller 2 is changed from 61 to 55, the reduction ratio R _p ″ of the platen roller 24 during reverse rotation of the drive motor is R _p ″ = ( Z _25b / Z _21a ) × (Z _34a / Z _25c ) ×
The _{(Z 27c / Z 34a) ×} (Z 22d / Z 27d) = (61/17) × (61/24) × (55/61) × (61/61) ≒ 8.223. Therefore, the relationship of the reduction ratio is R _p ″ <R _p. Therefore, when the rotation speed of the drive motor 21 is the same, the platen roller 2 is more rewound during sheet rewinding than during sheet conveyance.
It turns out that the rotation speed of is fast. That is, the sheet rewinding time can be shortened by making the reduction ratio of the platen roller 2 at the time of reverse rotation of the drive motor smaller than the reduction ratio of the platen roller 2 at the time of normal rotation of the drive motor. A drive system can be realized.

Here, the rewinding amount of the recording sheet of the platen roller 2 in this embodiment is calculated. Sector gear 27
When d rotates once, the number of teeth meshing with the gear 22d (the number of teeth Z = 61) fixed to the platen roller shaft 22 is 20, so the rotation amount of the platen roller 2 is 20/61 rotations. Therefore, the rewound amount δ _p of the recording sheet by the platen roller 2 is δ _p = π · d _p × (22/61) ≈18.438 (mm).

The margin 2 mm of the margin of the head of the recording sheet is added to the above numerical values so that the distance from the recording position on the platen roller 2 to the cutting position of the cutter 3 is 20.4 mm, and the platen roller 2 and the cutter 3 are Set the positional relationship of.

Next, the discharge / conveyance amount of the recording sheet by the discharge roller 4 in this embodiment will be calculated. The rotation speed ratio R _ph of the discharge roller 4 to the platen roller 2 when the drive motor 21 is driven in the reverse direction is R _ph = (Z _32a / Z _22d ) × (Z _33a / Z _32a ) × (Z
_23d / Z _33a ) = (38/61) x (38/38) x (24/38) = 0.3934.

Therefore, the gear portion and the gear of the sector gear 27d are
The rotation amount of the discharge roller 4 when the 22d is meshed is 20/61 / R _ph ≈0.8333.

Therefore, the discharge conveyance amount δ _h of the recording sheet by the discharge roller 2 at this time is δ _h = 0.8333 × π · d _h ≈33.249 (mm).

In the present embodiment, the distance from the recording sheet cutting position of the cutter 3 to the discharging roller 4 is set to 24 mm, so that the discharging roller 2 can completely discharge and convey the recording sheet.

The operation of the recording system A described above is as shown in the timing chart of FIG. 6 similarly to the above-mentioned embodiment. Therefore, as is clear from comparison with the timing chart of FIG. 16 described in the conventional example, since there is only one drive motor for driving the recording system, it is necessary to synchronize the two drive motors as in the conventional example. No need to move. Also, 1
The drive control of the motor is simple because the recording operation for the pages only rotates the drive motor in the forward direction and in the reverse direction. Further, the time required for the recording operation is shortened.

[Third Embodiment] Next, a third embodiment of the image recording apparatus to which the present invention is applied will be described with reference to the drawings. The image recording apparatus according to the present embodiment is also configured as a recording system of a facsimile apparatus in the same manner as the above-described embodiment, and is generally called a thermal recording apparatus. The members having the same functions and configurations as those of the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

{Structure of Drive System} The drive system of the recording system, which is a feature of this embodiment, will be described in detail below. FIG. 11 is a top plan view of the drive system of the image recording apparatus according to this embodiment, and FIG.
FIG. 12 is a side view of the drive system shown in FIG. 11 viewed from the direction of arrow X. In this embodiment, all the gears in the figure have a module m = 0.5.

The recording system A according to the present invention also drives the platen roller 2, the cutter 3, and the discharge roller 4 by only one common drive motor 21, as shown in FIG. Is configured as follows. The drive motor 21
Is fixed to a frame (not shown) of the apparatus main body, and a motor gear 21a (the number of teeth Z = 17) is attached to its shaft. The platen roller 2 and the discharge roller 4 are attached to a platen roller shaft 22 and a discharge roller shaft 23, respectively, and these shafts 22 and 23 are bearings 22a and 22b and bearings.
It is attached to a front side plate 24a and a rear side plate 24b which constitute a part of the frame of the apparatus main body via 23a and 23b.

The structure of each driving force transmitting means for transmitting the driving force of the drive motor 21 to the platen roller 2, the cutter 3 and the discharge roller 4 will be described below.

(First Driving Force Transmission Means and Second Driving Force Transmission Means) As shown in FIGS. 11 and 12, the motor gear 21a
The (number of teeth Z = 17) meshes with a gear 35a (number of teeth Z = 61) rotatably attached to a shaft 35 fixed to the front side plate 24a, and transmits a driving force from the drive motor 21. Then, a small-diameter gear 35b integrally formed with the gear 35a (the number of teeth Z =
24) is a front plate 24a and a rear plate 24 via bearings 27a and 27b.
front side plate of the driving force transmission shaft 27 mounted across b
The gear 27c (the number of teeth Z = 61) attached via the one-way clutch 27e is engaged with the 24a side. The one-way clutch 27e is formed integrally with the gear 27c, and transmits the driving force to the driving force transmission shaft 27b only when the gear 27c rotates in the direction of the arrow b '. Furthermore, the gear 27c
Engages with a gear 22c mounted on the front plate 24a side of the platen roller shaft 22 via a one-way clutch 22e. This one-way clutch 22e is also a gear
It is formed integrally with 22c and transmits the driving force to the roller shaft 22 only when the gear 22c rotates in the direction of arrow c.

The reduction ratio R _p of the platen roller 2 with respect to the drive motor 21 by the drive force transmission means having the above structure
Is R _p = (Z _35a / Z _21a ) × (Z _27c / Z _35b ) × (Z
The _{22c / Z 27c) = (61/17} ) × (61/24) × (61/61) ≒ 9.120.

Further, the front side plate 24a of the platen roller shaft 22
The gear 22c attached to the side meshes with the gear 26c (the number of teeth Z = 38) rotatably attached to the shaft 26 fixed to the front plate 24a, and the gear 26c is the discharge roller shaft.
The gear 23c (the number of teeth Z = 43) attached to the front side plate 24a of 23 through the one-way clutch 23f is meshed. The one-way clutch 23f is also integrally formed with the gear 23c, and transmits the driving force to the roller shaft 23 only when the gear 23c rotates in the direction of arrow d.

(Third Driving Force Transmission Means, Fourth Driving Force Transmission Means, and Fifth Driving Force Transmission Means) On the rear plate 24b side of the driving force transmission shaft 27, as shown in FIGS. A sector gear 27d whose teeth are cut is fixed to a part of the. As shown in FIG. 5, the sector gear 27d is a gear formed by leaving 20 teeth shown in the figure from a gear having a module m = 0.5 and the number of teeth Z = 61. And this sector gear
27d is a gear 22d (the number of teeth is Z =, where the 20 teeth are fixed to the rear plate 24b side of the platen roller shaft 22 during one rotation).
61) It is arranged so as to mesh with.

A crankshaft 28 is formed on the sector gear 27d at a position (about 10 mm in this embodiment) apart from the center of rotation by a predetermined amount. A crank arm 29 is attached to the crank shaft 28, and the tip of the crank arm 29 is attached to the connecting shaft 30.
It is connected to the cutter arm 31 via. The cutter 3 is connected to the cutter arm 31.

Now, the structure of the cutter 3 in this embodiment will be described. As shown in FIG. 4, the cutter 3 includes an upper blade 3a and a lower blade 3b. A torsion coil spring 3d is applied to a rotary shaft 3c provided at the end of the upper blade 3a,
Its tip is rotatably supported by the cutter side plate 3e. The upper blade 3a is pressed by the torsion coil spring 3d so as to rotate in the clockwise direction. Further, a stopper 3f is integrally formed at the end of the upper blade 3a, and the stopper 3f hits the lower blade 3b to stop the rotation of the upper blade 3a. A rotary shaft 3g provided at the end of the lower blade 3b is rotatably supported by the cutter side plate 3e, and its tip is fitted into the cutter arm 31. Further, a connecting shaft 3h is provided at the end of the lower blade 3b, and the connecting shaft 3h is fitted into the cutter arm 31 through an elongated hole 3i formed in the cutter side plate 3e. A cutter home position detection sensor (not shown) such as a micro switch is provided below the cutter arm 31 to detect whether the cutter 3 is in the standby position or the cutting position.

As shown in FIGS. 3 and 4, the rear side plate
The gear 22d fixed to the platen roller shaft 22 on the 24b side is
It meshes with a gear 32a (the number of teeth Z = 38) rotatably attached to a shaft 32 fixed to the rear side plate 24b, and the gear 32a is rotatably attached to a shaft 33 fixed to the rear side plate 24b. Gear 33a (the number of teeth Z = 38). The gear 33a is provided on the rear plate 24 of the discharge roller shaft 23.
It meshes with a gear 23d (number of teeth Z = 24) attached to the b side. A one-way clutch 23e for transmitting the driving force only in one direction is built in the center of the gear 23d.

With the driving force transmitting means having the above structure, the drive motor when the gear 33d and the sector gear 27d mesh with each other.
The reduction ratio R _p ′ of the platen roller 2 with respect to 21 is R _p ′ = (Z _35a / Z _21a ) × (Z _27c / Z _35b ) ×
(Z _22d / Z _27d ) = (61/17) x (61/24) x (61/61) = 9.120.

Therefore, the speed reduction ratio R _p by the drive force transmission means at the time of the normal rotation of the drive motor and the speed reduction ratio R _p ′ by the drive force transmission means at the time of the reverse rotation of the drive motor are equal. That is,
The number of teeth of each gear of the driving force transmission means is set so that the reduction ratios are equal.

The driving force transmission shaft of the sector gear 27d
As for the positional relationship between the mounting method of the crankshaft 28 and the crankshaft 28, as in the above-described embodiment, when the cutter 3 is at the standby position, it is set so as to be in the state shown in FIG.

{Operation of Driving System} Next, the operation of the driving system of the recording system according to the present embodiment will be described with reference to FIGS. 11, 12 and 3.

(Operation in Normal Rotation of Drive Motor) First, the operation when the drive motor 21 rotates in the normal direction and the motor gear 21a rotates in the direction of arrow a will be described. As shown in FIG. 12, when the motor gear 21a rotates in the direction of arrow a, the driving force is transmitted to the gear 35a and the gear 35 formed integrally with the gear 35a.
The driving force is transmitted from b to the gear 27c attached to the front plate 24a side of the driving force transmission shaft 27, and the gear 27c rotates in the direction of arrow b. Further, a gear meshing with the gear 27c.
22c rotates in the direction of arrow c, and the driving force is transmitted to the platen roller shaft 22 via the one-way clutch 22e. Further, the driving force of the drive motor 21 is fixed to the discharge roller shaft 23 via a gear 26c meshing with the gear 22c.
23c, the gear 23c rotates in the direction of arrow d,
The driving force is transmitted to the discharge roller shaft 23 via the one-way clutch 23f. That is, the normal rotation driving force of the drive motor 21 causes the platen roller 2 and the discharge roller 4 to rotate in the direction in which the recording sheet is conveyed. Since the one-way clutch 27e built in the gear 27c transmits only the rotational force in the direction of arrow b ', the driving force is transmitted to the driving force transmission shaft 27 when the drive motor 21 rotates in the normal direction (direction of arrow a). It will not be done.

Further, as the platen roller 2 and the discharge roller 4 rotate in the conveying direction of the recording sheet respectively, the gear 22d fixed to the rear side plate 24b of the platen roller shaft 22 rotates in the direction of arrow c, The gear 23d rotates in the arrow d'direction via the gears 32a and 33a. At this time,
Although the discharge roller shaft 23 rotates in the direction of arrow d, the one-way clutch 23 that transmits the driving force only in one direction (in this embodiment, the direction of arrow d) is interposed between the discharge roller shaft 23 and the gear 23d. The rotation of the gear 23d in the direction of the arrow d'is not transmitted to the discharge roller shaft 23.

As described above, when the drive motor 21 rotates in the direction of arrow a (normal rotation), the platen roller 2
The discharge roller 4 rotates in the direction of conveying the recording sheet, and the thermal head 1 records a predetermined image while conveying the sheet.

Here, when the transport amount when the platen roller 2 and the discharge roller 4 transport the recording sheet and the respective roller diameters in this embodiment are calculated, the reduction ratio R when the platen roller 2 rotates in the forward direction is calculated. _p is R _p ≈9.120, as calculated previously.

Similarly, the reduction ratio R _h when the discharge roller 4 rotates in the normal direction is R _h = (Z _35a / Z _21a ) × (Z _27c / Z _35c ) × (Z
_22c / Z _27c ) × (Z _26c / Z _22c ) × (Z _23c / Z
_26c ) = (61/17) x (61/24) x (61/61) x (38/61) x
(43/38) ≈ 6.429.

The facsimile apparatus of this embodiment is a GIV facsimile, and the recording resolution in the recording sheet conveying direction (sub-scanning direction) is 400 dpi (dots / inch). Therefore, the length L ₀ of one dot in the sub-scanning direction is L ₀ = 25.4 / 400 = 0.0635 (mm).

The drive motor 21 has a step angle of 7.5 °,
Since it is a 2-phase PM type stepping motor and is operated by 1-2 phase drive, the minimum step angle θ ₀ when the drive motor 21 rotates is θ ₀ = 7.5 ° / 2 = 3.75 °.

Therefore, the diameter d _p of the platen roller 2 is
The minimum step angle θ _p0 (rad) of the platen roller 2 is obtained by the following equation.

L ₀ = (d _p / 2) × θ _p0

Here, θ _p0 = (θ ₀ × π / 180 °) R _p ∴d _p = 2 × L ₀ / θ _p0 = {2 × L ₀ / (θ ₀ × π / 180 °)} × R _p ≈ 17.697 (mm).

However, when the diameter d _p of the platen roller 2 is actually manufactured with this size and an image is recorded, the surface of the platen roller 2 is deformed and the load for conveying the recording sheet causes the recording sheet to be damaged. The carry amount decreases, and the image shrinks. Therefore, the design value of the diameter d _p of the platen roller 2 is set to a value slightly larger than the calculated value, and is determined as follows.

D _p = 17.90 ± 0.05 (mm)

When recording an image, the drive motor 21 is set to 40
Since the driving is performed at 0 pps (pulses / sec), the length L ₁ that the recording sheet is conveyed by the platen roller 2 in one second is as follows assuming that the image does not expand or contract.

L ₁ = L ₀ × 400 = 25.40 (mm)

As a result, in order to prevent the recording sheet from being bent between the platen roller 2 and the discharge roller 4, the discharge roller 4 conveys the recording sheet for a length of 1 second. Slightly larger than the length,
When set to 25.42 (mm), the diameter d _{h of the} discharge roller 4
And the discharge roller angular rotation speed ω _h are as follows.

D _h / 2 × ω _h = 25.42

Here, the discharge roller angular rotation speed ω _h is ω _h = (3.75 ° × 400 × π / 180 °) / R _h ≈4.0722 (rad / s).

Therefore, d _h ≈12.4846 (mm).

As with the platen roller 2, the design value of the diameter d _h of the discharge roller 4 is set to a value slightly larger than the calculated value, and d _h = 12.70 ± 0.05 (mm).

(Operation when the drive motor reversely rotates) Next, the operation when the drive motor 21 reversely rotates and the motor gear 21a rotates in the direction of the arrow a'will be described. As shown in Figure 12,
When the motor gear 21a rotates in the direction of arrow a ', the gear 35a
Drive force is transmitted to the gear 35a and is integrally formed with the gear 35a.
The driving force is transmitted from b to the gear 27c attached to the front plate 24a side of the driving force transmission shaft 27, and the gear 27c is indicated by the arrow b '.
Rotate in the direction. The rotation of the gear 27c in the arrow c direction is transmitted to the driving force transmission shaft 27 via a one-way clutch 27e.

The rear side plate 24b of the driving force transmitting shaft 27
The sector gear 27d fixed to the side rotates in the arrow b'direction, and at the same time, the crankshaft 28 provided on the sector gear 27d rotates in the arrow b'direction around the driving force transmission shaft 27. As a result, the reverse driving force of the drive motor 21 is transmitted to the cutter 4 via the crank arm 29 and the cutter arm 31. That is, the arrow b'of the crankshaft 28
By the rotation in the direction, the crank arm 29 and the cutter arm 31 move from the position shown in FIG. 3 (a) to the position shown in FIG. 3 (b), and the cutter 3 moves from the standby position to the cutting position. The trailing edge of the recording sheet on which predetermined recording has been performed is cut.

While the cutter 3 is moving from the standby position to the cutting position, the gear portion of the sector gear 27d does not mesh with the gear 33d as shown in FIG. 3B, so the platen roller 2 The driving force is not transmitted to the discharge roller 4, and is similarly not transmitted to the discharge roller 4. That is, the recording sheet is cut while the platen roller 2 and the discharge roller 4 are stopped.

When the sector gear 27d further rotates in the direction of the arrow b'from the state shown in FIG. 3B, the state shown in FIG.
As shown in (c), the gear portion of the sector gear 27d meshes with the gear 22d fixed to the platen roller shaft 22, and the gear 22d rotates in the direction of arrow c '. As a result, the platen roller 2 rotates in the direction opposite to the sheet conveying direction, and the unrecorded recording sheet sandwiched between the roller 2 and the thermal head 1 is rewound. Further, the rotation of the gear 22d in the direction of the arrow c'through the gears 32a and 33a,
23d rotates in the direction of arrow d, and the discharge roller shaft 23 rotates in the direction of arrow d by the action of the one-way clutch 23e described above. As a result, the discharge roller 4 rotates in the sheet conveying direction, and the recording sheet, on which the predetermined recording is performed and the rear end side is cut, is discharged and conveyed onto the sheet tray 6 outside the apparatus by the discharge roller 4 and the discharge roller 5. That is, the operation of rewinding the leading end of the unrecorded recording sheet to the recording position and the recording sheet on which the predetermined recording is performed and the trailing end side is cut are set in the sheet tray 6.
The operation of discharging upward is performed at the same time.

On the other hand, while the gear portion of the sector gear 27d and the gear 22d fixed to the platen roller shaft 22 mesh with each other, the gear 22c fixed to the front plate 24a side of the platen roller shaft 22 moves in the direction of arrow c '. Rotate. At this time, the roller shaft 22 is driven by the driving force transmitted from the rear plate 24b to the arrow c '.
Is rotating in the direction. Here, the angular rotation speed of the gear 22c in the direction of arrow c'is ω ₁ , and the arrow c'of the platen roller shaft 22 is
When the direction of the angular rotation speed and ω _2, the one-way clutch 2
In order for 2e to operate normally, ω ₁ −ω ₂ ≧ 0, that is, ω ₁ ≧ ω ₂ . As described above, the speed reduction ratio R _p of the platen roller 2 for driving the motor 21 when the platen roller 2 is rotated forward, the speed reduction ratio R _p of the platen roller 2 for driving the motor 21 when the platen roller 2 is reversed 'is Since the number of teeth of the gear train is determined so as to be the same, the rotation speeds of the gear 22c and the platen roller shaft 22 are equal, and ω ₁ = ω ₂ . Therefore, the one-way clutch 22e does not affect the rotation of the gear 22c and the platen roller shaft 22.

Here, the relationship of the reduction ratio is R _p <R _p ′
If the number of teeth of the gears 22d and 27d is set so that the rotation speed of the platen roller shaft 22 when the drive motor 21 rotates in the reverse direction becomes lower than the rotation speed of the gear 22c. That is, ω ₁ >
It is ω ₂ . At this time, no problem occurs in the one-way clutch 22e.

However, assuming that the reduction ratio R _p and the rotation speed at the time of reverse rotation of the motor are the same, the relation of the reduction ratio is R _p <
When the number of teeth of the gears 22d and 27d is set so as to be R _p ′ and when the number of teeth of the gears 22 d and 27 d is set so that the reduction ratio is R _p = R _p ′, Comparing the rotation speeds of the platen roller 2 during reverse rotation, the rotation speed in the former case becomes slower than the rotation speed in the latter case. That is, it takes more time to rewind the recording sheet after cutting. Therefore, it is unsuitable for the present invention aimed at shortening the recording time. On the other hand, when the number of teeth of the gears 22d and 27d is set so that the speed reduction ratio relationship becomes R _p > R _p ′, the rotation speed of the platen roller shaft 22 during reverse rotation of the motor becomes faster than the rotation speed of the gear 22c. . That is, ω
₁ <ω ₂ . This may result in damage to the drive train.

Therefore, in the present invention aimed at shortening the recording time, it is found that it is optimal to set the relationship of the reduction ratio to R _p = R _p ′.

While the gear portion of the sector gear 27d and the gear 22d fixed to the platen roller shaft 22 are meshed, the gear 23c fixed to the front side plate 24a side of the discharge roller shaft 23 is It rotates in the direction of arrow d'via 26c. At this time, the roller shaft 23 is rotating in the direction of arrow d due to the transmission of the driving force on the side of the rear plate 24b. However, as described above, the gear 23c has the built-in one-way clutch 23f that transmits only the rotational force in the direction of the arrow d to the roller shaft 23, so there is no problem even if the gears rotate in the opposite directions.

When the sector gear 27d further rotates in the direction of arrow b'from the state shown in FIG. 3C, the state shown in FIG.
As shown in (a), the meshed state of the gear portion of the sector gear 27d and the gear 22d is released, and the gear 22d stops rotating. As a result, the platen roller 2 and the discharge roller 4 stop rotating. At this time, the leading edge of the unrecorded recording sheet is rewound by about 2 mm from the recording position to the position of the cutter 3, and the recording sheet on which the predetermined recording is performed and the trailing edge is cut is completely discharged onto the sheet tray 6. Has been done. The rewinding amount of the recording sheet by the platen roller 2 is set by the number of teeth of the sector gear 27d and the distance relationship from the recording position to the cutting position. In this embodiment, the sector gear is
The number of teeth of 32d is 20, and the distance from the recording position to the cutting position is set to 20.4 mm. In addition, the discharge roller 3
Since the discharging amount of the recording sheet according to (4) needs to be larger than the distance from the cutting position to the discharging position, the number of teeth of the gears 32a, 33a, 23d is set in consideration of this, and in this embodiment, it is confirmed by the calculation described later. As described above, the distance is set to 24 mm.

Then, as shown in FIG.
When the cutter home position detection sensor (not shown) detects that the cutter 3 is at the standby position after the meshed state of 27d and 22d is released, the drive motor 21 stops rotating. When further recording is required, the motor is driven again and the above-described operation is repeated.

As described above, when the drive motor 21 rotates (reverses) in the direction of the arrow a ', the cutter 4 drives to cut the recording sheet, and after the cutting, the platen roller 2 moves in the sheet conveying direction. Rotates in the opposite direction to rewind the recording sheet, and at the same time, the discharge roller 4 rotates in the sheet conveying direction to discharge and convey the recording sheet.

Here, the recording sheet rewinding amount of the platen roller 2 in this embodiment is calculated. Sector gear 27
When d rotates once, the number of teeth meshing with the gear 22d (the number of teeth Z = 61) fixed to the platen roller shaft 22 is 20, so the rotation amount of the platen roller 2 is 20/61 rotations. Therefore, the rewound amount δ _p of the recording sheet by the platen roller 2 is δ _p = π · d _p × (22/61) ≈18.438 (mm).

The margin 2 mm of the margin of the head of the recording sheet is added to the above numerical values so that the distance from the recording position on the platen roller 2 to the cutting position of the cutter 3 is 20.4 mm, and the platen roller 2 and the cutter 3 Set the positional relationship of.

Next, the discharge / conveyance amount of the recording sheet by the discharge roller 4 in this embodiment will be calculated. The rotation speed ratio R _ph of the discharge roller 4 to the platen roller 2 when the drive motor 21 is driven in the reverse direction is R _ph = (Z _32a / Z _22d ) × (Z _33a / Z _32a ) × (Z
_23d / Z _33a ) = (38/61) x (38/38) x (24/38) = 0.3934.

Therefore, the gear portion and the gear of the sector gear 27d are
The rotation amount of the discharge roller 4 when the 22d is meshed is 20/61 / R _ph ≈0.8333.

Therefore, the discharge conveyance amount δ _h of the recording sheet by the discharge roller 2 at this time is δ _h = 0.8333 × π · d _h ≈33.249 (mm).

In this embodiment, since the distance from the recording sheet cutting position of the cutter 3 to the discharge roller 4 is set to 24 mm, the discharge roller 2 can completely discharge and convey the recording sheet.

The operation of the recording system A described above is as shown in the timing chart of FIG. 6 similarly to the above-mentioned embodiment. Therefore, as is clear from comparison with the timing chart of FIG. 16 described in the conventional example, since there is only one drive motor for driving the recording system, it is necessary to synchronize the two drive motors as in the conventional example. No need to move. Also, 1
The drive control of the motor is simple because the recording operation for the pages only rotates the drive motor in the forward direction and in the reverse direction. Furthermore, the time required for the recording operation is shortened.

[Other Embodiments] In the third embodiment described above, the gears 35a, 35 to which the driving force is transmitted from the drive motor 21.
b is a gear 27c provided on the front plate 24a side of the driving force transmission shaft 27
However, the present invention is not limited to this. For example, as shown in FIG.
a and a gear 22 provided on the front side plate 24a side of the platen roller shaft 22
The gears 35a and 35b may be interposed between the gears c and c. As a result, the number of gears interposed between the drive motor 21 and the platen roller 2 is smaller than that in the third embodiment described above, and a more accurate sheet conveying operation can be performed.

Similarly, as shown in FIG. 14, the gears 35a and 35b are provided between the motor gear 21a and the gear 26c rotatably attached to the shaft 26 fixed to the front plate 24.
It may be configured to intervene.

Further, as shown in FIG. 15, the motor gear
21a and a gear provided on the front plate 24a side of the platen roller shaft 22
The gears 35a and 35b are interposed between the gears 22a and 22c, and similarly, between the motor gear 21a and the gear 23c provided on the front side plate 24a side of the discharge roller shaft 23, the gears 36a and 35a having the same configuration as the gears 35a and 35b, 36b may be interposed.

The operation of the drive system shown in FIGS. 13 to 15 is similar to that of the third embodiment described above.

[0173]

As described above, the platen roller,
By configuring a drive force transmission system for driving the discharge roller and cutter with a common drive motor, the two rollers that were required when the platen roller and the discharge roller were driven by different motors were synchronized with each other. It is not necessary to control the rotation to rotate, and the total recording time from the start of recording to the completion of discharge can be shortened.

Further, in the above-described first and second embodiments, the speed reduction ratio of the platen roller to the drive motor is changed between forward rotation and reverse rotation of the motor.
Even if the rotation speed of the motor is the same, the time from the start of recording to the start of recording of the next page can be shortened, and the total recording time can be further shortened in addition to the above effects. .

Further, since the platen roller, the discharge roller and the cutter are driven by the common drive motor, the cost and size and weight of the apparatus can be reduced.

Further, since the rewinding amount of the recording sheet by the platen roller is set by the number of teeth of the sector gear, the recording sheet can be indexed and waste of the recording sheet can be eliminated. Further, since the reverse rotation drive force transmission system is set so that the discharge amount of the recording sheet by the discharge roller during the reverse rotation of the motor becomes longer than the distance from the position of the cutter to the position of the discharge roller, the The recording sheet can be reliably discharged and conveyed outside the apparatus.

Further, by configuring the image recording apparatus of the present invention as the recording system of the facsimile apparatus, the operation of the recording system and the operation of the reading system can be made completely independent.
It is possible to provide a facsimile device that can perform a reading operation even during recording.

[Brief description of drawings]

FIG. 1 is a plan view of the main components of an image recording apparatus according to the present invention as viewed from above.

FIG. 2 is a side view of the drive system of the image recording apparatus shown in FIG. 1 viewed from the direction of arrow X.

FIG. 3 is a side view of the drive system of the image recording apparatus shown in FIG. 1, viewed from the direction of arrow Y.

FIG. 4 is a perspective view of the drive system shown in FIG.

FIG. 5 is an enlarged side view of a sector gear to which a crankshaft is attached.

FIG. 6 is a timing chart of a drive motor in the recording system.

FIG. 7 is a main cross-sectional view of a facsimile apparatus including the image recording apparatus of the present invention.

FIG. 8 is an external perspective view of the facsimile device.

FIG. 9 is a top plan view showing the main components of the image recording apparatus in the second embodiment.

FIG. 10 is a side view of the drive system of the image recording apparatus shown in FIG. 9 as seen in the direction of arrow X.

FIG. 11 is a top plan view showing the main components of the image recording apparatus in the third embodiment.

FIG. 12 is a side view of the drive system of the image recording apparatus shown in FIG. 11, viewed from the direction of arrow X.

13A and 13B are a plan view and a side view, respectively, showing main components of an image recording apparatus according to another embodiment.

14A and 14B are a plan view and a side view showing main components of an image recording apparatus according to another embodiment.

15A and 15B are a plan view and a side view showing the main components of an image recording apparatus according to another embodiment.

FIG. 16 is a diagram showing an operation of a recording system of a conventional facsimile apparatus.

[Explanation of symbols]

A ... recording system, B ... reading system, C ... operation unit, G ... original, S ...
Recording sheet, 1 ... Thermal head, 2 ... Platen roller, 3 ... Cutter, 3a ... Upper blade, 3b ... Lower blade, 3c ... Rotating shaft, 3d ... Torsion coil spring, 3e ... Cutter side plate,
3f ... Stopper, 3g ... Rotating shaft, 3h ... Connecting shaft, 3i
... elongated holes, 4 ... discharge rollers, 5 ... discharge rollers, 6 ... sheet tray, 7 ... guide shaft, 11 ... document placing table, 12a ... pre-conveying roller, 12b ... pressing piece, 13a ... separation roller, 13b
... Pressing piece, 14a, 14b ... Conveying roller pair, 15a, 15b ... Ejecting roller pair, 16 ... Ejecting tray, 17 ... Photoelectric conversion element, 18 ...
Handset, 19 ... Electrical board, 20 ... Power supply section, 21 ... Drive motor, 21a ... Motor gear, 22 ... Platen roller shaft, 22
a, 22b ... Bearing, 22c, 22d ... Gear, 22e ... One-way clutch, 23 ... Discharge roller shaft, 23a, 23b ... Bearing, 23
c, 23d ... Gear, 23e, 23f ... One-way clutch, 24
a ... front side plate, 24b ... rear side plate, 25 ... rocking member, 25a ... shaft,
25b ... first swing gear, 25c ... second swing gear, 26 ... shaft, 26
a, 26b, 26c ... Gear, 27 ... Driving force transmission shaft, 27a, 27b
... Bearing, 27c ... Gear, 27d ... Sector gear, 27e ... One-way clutch, 28 ... Crank shaft, 29 ... Crank arm, 30 ... Connecting shaft, 31 ... Cutter arm, 32, 33 ... Shaft, 32
a, 33a ... Gear, 34 ... Shaft, 34a ... Gear, 35, 36 ... Shaft, 35
a, 35b, 36a, 36b ... Gear

Claims (28)

[Claims] 1. A platen roller that conveys a recording sheet while supporting it, a recording unit that presses the recording sheet against the platen roller to record an image, and a cutter that cuts the recorded recording sheet into a predetermined length. And a discharge roller that discharges the cut recording sheet to the outside of the apparatus, a common drive motor that drives the platen roller, the discharge roller, and the cutter, and a normal drive motor of the drive motor. Forward rotation driving force transmission means for transmitting the driving force during rotation to the platen roller and the discharge roller, and reverse rotation driving force transmission means for transmitting the driving force during reverse rotation of the drive motor to the platen roller, the discharge roller, and the cutter. A drive force transmission switching means for selectively transmitting the drive force of the drive motor to each of the drive force transmission means, the drive motor and the drive force transmission switch The image recording apparatus characterized by comprising control means for controlling the driving means, a. 2. The normal rotation driving force transmission means rotationally drives the platen roller and the discharge roller in the sheet conveying direction during normal rotation of the drive motor, and the reverse rotation driving force transmission means drives the cutter during reverse rotation of the drive motor, and After cutting the recording sheet by the cutter, the platen roller is rotationally driven in a direction opposite to the sheet transport direction, and at the same time, the discharge roller is rotationally driven in the sheet transport direction.
The image recording device described in 1. 3. The reversing drive force transmitting means has a sector gear having a gear portion only on a part of the outer circumference, and the rewinding amount of the recording sheet by the platen roller is set by the number of teeth of the sector gear. The image recording device according to claim 2. 4. The reverse rotation driving force transmitting means is set so that a discharge / conveyance amount of the recording sheet by the discharge roller is longer than a distance from a cutting position by the cutter to a discharge position by the discharge roller. The image recording apparatus according to claim 2. Wherein said speed reduction ratio and R _p of the platen roller with respect to the drive motor by the forward driving force transmitting means, the speed reduction ratio R _p of the platen roller with respect to the drive motor by the reverse drive force transmission means', the relationship between the R _p " 3. The image recording apparatus according to claim 1, wherein each of the driving force transmitting means is set so that R _p = R _p ′, R _p > R _p ″. 6. A platen roller that conveys a recording sheet while supporting it, a recording unit that presses the recording sheet against the platen roller to record an image, and a cutter that cuts the recorded recording sheet into a predetermined length. And a discharge roller that discharges the cut recording sheet to the outside of the apparatus, a common drive motor that drives the platen roller, the discharge roller, and the cutter, and a normal drive motor of the drive motor. Forward rotation driving force transmission means for transmitting the driving force during rotation to the platen roller and the discharge roller, and reverse rotation driving force transmission means for transmitting the driving force during reverse rotation of the drive motor to the platen roller, the discharge roller, and the cutter. An image recording apparatus comprising: a control unit that controls driving of the drive motor. 7. The normal rotation driving force transmission means rotationally drives the platen roller and the discharge roller in the sheet conveying direction during normal rotation of the drive motor, and the reverse rotation driving force transmission means drives the cutter during reverse rotation of the drive motor, and 7. After the cutting of the recording sheet by the cutter, the platen roller is rotationally driven in a direction opposite to the sheet conveying direction, and at the same time, the discharge roller is rotationally driven in the sheet conveying direction.
The image recording device described in 1. 8. The reversing drive force transmitting means has a sector gear having a gear portion only on a part of the outer circumference, and the rewinding amount of the recording sheet by the platen roller is set by the number of teeth of the sector gear. The image recording apparatus according to claim 7, which is characterized in that. 9. The reverse rotation driving force transmitting means is set so that a discharge / conveyance amount of a recording sheet by the discharge roller is longer than a distance from a cutting position by the cutter to a discharge position by the discharge roller. The image recording apparatus according to claim 7. Wherein said relationship between the reduction ratio and the R _p of the platen roller with respect to the drive motor by the forward driving force transmitting means, the speed reduction ratio R _p of the platen roller with respect to the drive motor by the reverse drive force transmission means', R _p The image recording apparatus according to claim 6 or 7, wherein each of the driving force transmitting means is set so that = R _p ′. 11. A platen roller that conveys a recording sheet while supporting it, a recording unit that presses the recording sheet against the platen roller to record an image, and a cutter that cuts the recorded recording sheet into a predetermined length. An image recording apparatus comprising: a discharge roller configured to discharge a cut recording sheet to the outside of the apparatus; and a detection unit configured to detect a standby position of the cutter, which drives the platen roller, the discharge roller, and the cutter. A common drive motor, a control unit that controls the drive of the drive motor, and a first drive force transmission that transmits the drive force so that the platen roller rotates in the sheet conveying direction when the drive motor is normally driven. A second driving force transmission unit that transmits a driving force so that the discharge roller rotates in a sheet conveying direction when the drive motor is normally driven. Third driving force transmitting means for transmitting a driving force so that the cutter operates when the drive motor rotates in the reverse direction, and the platen roller rotates in a direction opposite to the sheet conveying direction when the drive motor rotates in the reverse direction. A fourth driving force transmitting unit that transmits a driving force to the discharge roller, and a fifth driving force transmitting unit that transmits the driving force so that the discharge roller rotates in the sheet conveying direction when the drive motor rotates in the reverse direction. The first driving force transmitting means swings to a position where the driving force is transmitted so that the platen roller rotates in the sheet conveying direction when the driving motor is normally driven, and the driving force is applied to the platen roller when the driving motor is driven in the reverse direction. Has a first oscillating gear that oscillates to a position that does not transmit the drive force, and the second drive force transmitting means applies the drive force so that the discharge roller rotates in the sheet conveying direction when the drive motor rotates in the normal direction. A second oscillating gear that oscillates to a position that reaches and reaches a position where the driving force is not transmitted to the discharge roller when the drive motor is driven in the reverse direction; A third swing gear that swings to a position where the driving force is transmitted so that the cutter operates, and swings to a position where the driving force is not transmitted to the cutter when the drive motor is normally rotated, The transmission means makes one rotation while the cutter operates once, and the platen roller rotates in the opposite direction to the sheet conveying direction for a certain period of time from when the cutter has finished cutting the recording sheet to when it returns to the standby position. As described above, the fifth driving force transmitting means includes the notch gear for transmitting the driving force, and the fifth driving force transmitting means causes the discharging roller to convey the sheet only when the platen roller rotates in the direction opposite to the sheet conveying direction by the fourth driving force transmitting means. Having a one-way clutch for transmitting the driving force to rotate the direction, the image recording apparatus characterized by. 12. A deceleration ratio R _p of the platen roller to the drive motor by the first driving force transmission means and a deceleration ratio R _p ′, R _p ″ of the platen roller to the drive motor by the fourth driving force transmission means. The image recording apparatus according to claim 11, wherein each of the driving force transmitting means is set so that the relations are R _p = R _p ′ and R _p > R _p ″. 13. The image recording device according to claim 11, wherein the first oscillating gear and the second oscillating gear are the same. 14. The image recording apparatus according to claim 11, wherein the first oscillating gear, the second oscillating gear, and the third oscillating gear are the same. 15. The control means drives the drive motor in the normal direction to finish the image recording for one page, conveys the cutting position of the recording sheet to the cutting position by the cutter, and then the detection means waits for the cutter. The drive motor is driven in reverse until the return to the position is detected, the drive motor is driven in the forward direction again when there is next page recording, and the drive motor is stopped when there is no next page recording. Controlling, claim 11, claim 12, claim 13 or claim 1
The image recording device according to any one of 4 above. 16. The method according to claim 11, wherein the number of teeth of the notched gear included in the fourth driving force transmitting means is determined in relation to the distance from the recording position to the cutting position.
The image recording apparatus according to claim 2, claim 13, claim 14, or claim 15. 17. The position of the discharge roller is determined such that the amount of conveyance of the recording sheet by the discharge roller is longer than the distance from the cutting position by the cutter to the discharge position by the discharge roller. Claim 1
1, claim 12, claim 13, claim 14, claim 15
Alternatively, the image recording apparatus according to claim 16. 18. A platen roller that supports and conveys a recording sheet, recording means that presses the recording sheet against the platen roller to record an image, and a cutter that cuts the recorded recording sheet into a predetermined length. An image recording apparatus comprising: a discharge roller configured to discharge a cut recording sheet to the outside of the apparatus; and a detection unit configured to detect a standby position of the cutter, which drives the platen roller, the discharge roller, and the cutter. A common drive motor, a control unit that controls the drive of the drive motor, and a first drive force transmission that transmits the drive force so that the platen roller rotates in the sheet conveying direction when the drive motor is normally driven. A second driving force transmission unit that transmits a driving force so that the discharge roller rotates in a sheet conveying direction when the drive motor is normally driven. Third driving force transmitting means for transmitting a driving force so that the cutter operates when the drive motor rotates in the reverse direction, and the platen roller rotates in a direction opposite to the sheet conveying direction when the drive motor rotates in the reverse direction. A fourth driving force transmitting unit that transmits a driving force to the discharge roller, and a fifth driving force transmitting unit that transmits the driving force so that the discharge roller rotates in the sheet conveying direction when the drive motor rotates in the reverse direction. The first driving force transmitting means swings to a position where the driving force is transmitted so that the platen roller rotates in the sheet conveying direction when the driving motor is normally driven, and the driving force is applied to the platen roller when the driving motor is driven in the reverse direction. Has a first oscillating gear that oscillates to a position that does not transmit the drive force, and the second drive force transmitting means applies the drive force so that the discharge roller rotates in the sheet conveying direction when the drive motor rotates in the normal direction. A second oscillating gear that oscillates to a reaching position and oscillates to a position at which a driving force is not transmitted to the discharge roller when the driving motor is driven in the reverse direction, and the third driving force transmitting means includes a driving motor and a cutter. There is a third one-way clutch interposed between the third one-way clutch and transmitting the driving force so that the cutter operates only when the driving motor is driven in the reverse direction. It has a notched gear that rotates, and transmits a driving force so that the platen roller rotates in the direction opposite to the sheet conveying direction for a certain period of time from when the cutter finishes cutting the recording sheet to when it returns to the standby position. The fifth driving force transmitting means transmits the driving force so that the discharge roller rotates in the sheet conveying direction only when the platen roller rotates in the direction opposite to the sheet conveying direction by the fourth driving force transmitting means. With the fifth one-way clutch to be,
An image recording device characterized by the above. 19. A deceleration ratio R _p of the platen roller to the drive motor by the first driving force transmission means and a deceleration ratio R _p ′, R _p ″ of the platen roller to the drive motor by the fourth driving force transmission means. The image recording apparatus according to claim 18, wherein each of the driving force transmitting means is set so that the relations are R _p = R _p ′ and R _p > R _p ″. 20. The image recording apparatus according to claim 18, wherein the first oscillating gear and the second oscillating gear are the same. 21. The control means drives the drive motor in the normal direction to finish the image recording for one page, conveys the cutting position of the recording sheet to the cutting position by the cutter, and then the cutter waits by the detecting means. The drive motor is driven in reverse until the return to the position is detected, the drive motor is driven in the forward direction again when there is next page recording, and the drive motor is stopped when there is no next page recording. 21. The image recording apparatus according to claim 18, which is controlled. 22. The number of teeth of a notched gear included in the fourth driving force transmitting means is determined in relation to a distance from a recording position to a cutting position.
The image recording device according to claim 9, 20 or 21. 23. The position of the discharge roller is determined so that the amount of conveyance of the recording sheet by the discharge roller is longer than the distance from the cutting position by the cutter to the discharge position by the discharge roller. Claim 1
8, claim 19, claim 20, claim 21 or claim 2
2. The image recording device according to any one of 2. 24. A platen roller that conveys a recording sheet while supporting it, a recording unit that presses the recording sheet against the platen roller to record an image, and a cutter that cuts the recorded recording sheet into a predetermined length. An image recording apparatus comprising: a discharge roller configured to discharge a cut recording sheet to the outside of the apparatus; and a detection unit configured to detect a standby position of the cutter, which drives the platen roller, the discharge roller, and the cutter. A common drive motor, a control unit that controls the drive of the drive motor, and a first drive force transmission that transmits the drive force so that the platen roller rotates in the sheet conveying direction when the drive motor is normally driven. A second driving force transmission unit that transmits a driving force so that the discharge roller rotates in a sheet conveying direction when the drive motor is normally driven. Third driving force transmitting means for transmitting a driving force so that the cutter operates when the drive motor rotates in the reverse direction, and the platen roller rotates in a direction opposite to the sheet conveying direction when the drive motor rotates in the reverse direction. A fourth driving force transmitting unit that transmits a driving force to the discharge roller, and a fifth driving force transmitting unit that transmits the driving force so that the discharge roller rotates in the sheet conveying direction when the drive motor rotates in the reverse direction. The first driving force transmitting means is interposed between the drive motor and the platen roller, and transmits the driving force so that the platen roller rotates in the sheet conveying direction only when the drive motor is normally driven. The second driving force transmitting means is interposed between the drive motor and the discharge roller so that the discharge roller rotates in the sheet conveying direction only when the drive motor is normally driven. A second one-way clutch for transmitting a driving force, wherein the third driving force transmitting means is interposed between the driving motor and the cutter, and transmits the driving force so that the cutter operates only when the driving motor is driven in the reverse direction. A third one-way clutch, wherein the fourth driving force transmitting means makes one rotation while the cutter operates once, and only for a certain period of time from when the cutter finishes cutting the recording sheet to when it returns to the standby position. A platen roller has a notched gear that transmits a driving force so that the platen roller rotates in a direction opposite to the sheet conveying direction, and the fifth driving force transmitting means causes the platen roller to move in the sheet conveying direction by the fourth driving force transmitting means. Has a fifth one-way clutch that transmits a driving force so that the discharge roller rotates in the sheet conveying direction only when rotating in the reverse direction. 25. The control means drives the drive motor to rotate in the normal direction to finish the image recording for one page, conveys the cutting position of the recording sheet to the cutting position by the cutter, and then the cutter waits by the detecting means. The drive motor is driven in reverse until the return to the position is detected, the drive motor is driven in the forward direction again when there is next page recording, and the drive motor is stopped when there is no next page recording. The image recording apparatus according to claim 24, which is controlled. 26. The number of teeth of a notched gear included in the fourth driving force transmitting means is determined in relation to a distance from a recording position to a cutting position.
5. The image recording device according to item 5. 27. The position of the discharge roller is determined such that the conveyance amount of the recording sheet by the discharge roller is longer than the distance from the cutting position by the cutter to the discharge position by the discharge roller. Claim 2
27. The image recording device according to claim 25. Reduction ratio and R _p of 28. The platen roller with respect to the drive motor by the first drive force transmitting means, the relationship between the reduction ratio R _p 'of the platen roller with respect to the drive motor by the fourth driving force transmission unit, R 28. The image recording apparatus according to claim 24, claim 25, claim 26 or claim 27, wherein each of the driving force transmitting means is set so that _p = R _p ′.