JP3219137B2 - Printer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printer, and more particularly to a printer which prints photographic paper placed on a paper tray by reciprocatingly moving the photographic paper.

[0002]

2. Description of the Related Art In the case of a video printer, a small photographic paper is placed on a paper tray, a print head in which print elements are arranged in a line is brought into contact with the paper, and the print tray is reciprocated. Is scanned on photographic paper to print.

[0003]

If the print head has the length of the paper width, printing can be completed only by reciprocating the paper tray once. If it is shorter, the print head can be moved in a direction orthogonal to the reciprocating direction of the paper tray to complete printing by a plurality of reciprocating operations. In this case, a unique drive mechanism for sliding the print head may be provided. However, the inventor of the present invention has devised a configuration in which the drive source is omitted by using the drive force for reciprocating the paper tray. did. That is, a rack is provided in the paper tray, and when the paper tray reciprocates, it meshes with a gear provided on the frame side to rotate the gear, and the print head is slid by the rotational force.

However, if the rack of the paper tray drives the gears during scanning while the print head is in contact with the photographic paper, it is known that vibration occurs and the printed image is disturbed. Was. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a printer device capable of preventing a disturbance of a printed image while omitting a driving source.

[0005]

In order to achieve the above object, according to the present invention, there is provided a frame, and a predetermined photographic paper can be placed on the upper surface while being supported so as to be able to reciprocate with respect to the frame. The paper tray and the frame are slidably supported in a direction substantially orthogonal to the paper tray with respect to the frame, and abut on the photographic paper placed on the paper tray. A slide head for scanning and printing on the photographic paper in accordance with the reciprocating operation, a rack provided on the paper tray side, and a gear provided on the frame side, and a predetermined range during the reciprocating operation of the paper tray. The rack and the gears mesh with each other to generate a driving force to slide the slide head, and the slide head. During printing is a configuration comprising a retracting mechanism for disabled mesh by shifting the relative positional relationship between the rack and the gear during movement of the paper tray along the mesh surface.

[0006] In the invention according to claim 1 configured as described above, the paper tray is supported so as to be able to reciprocate with respect to the frame, and the paper tray has a predetermined photographic paper placed on the upper surface thereof. Reciprocate. On the other hand, the slide head is supported so as to be slidable with respect to the frame in a direction substantially perpendicular to the paper tray, and is capable of abutting the photographic paper placed on the paper tray. Therefore, the paper tray can scan over the photographic paper over a predetermined width by reciprocating operation. If the paper tray is slid in a direction perpendicular to the moving direction of the paper tray for each scan, a necessary range on the photographic paper is obtained. Is scanned to enable printing.

The head slide mechanism slides the slide head. The head slide mechanism includes a rack provided on the paper tray side and a gear provided on the frame side. Therefore, when the paper tray reciprocates, the rack slides. The rack and the gear mesh with each other in the formation range. Then, a driving force is generated in the gear, and the driving force is mechanically connected to slide the slide head. On the other hand, if this is the case, the printed image may be disturbed as described above,
During printing by the slide head, the retraction mechanism shifts the relative position of the rack and the gear along the meshing surface when the paper tray moves. Then, the two cannot be meshed with each other, so that vibration and the like do not occur, and no image disturbance occurs.

The frame is not limited as long as it supports a paper tray or the like, and its shape is not limited. The material is also widely applicable such as a metal material and a resin material. Further, the frame means to support each part, and is not limited to a chassis, but may be a case. The paper tray may be of any type as long as it can reciprocate with respect to the frame, and may have various configurations including a drive mechanism. For example, the driving may be performed by providing a driving gear and a rack, or the driving may be performed by a pulling force while winding a wire. Various printing methods can be used for the photographic paper. Sublimation-type image forming or heat-forming image forming can be used as long as the slide head is brought into contact and scanned for printing. Is not particularly limited.

In this sense, the slide head is compatible with a printing method on photographic paper, and scans the photographic paper surface by a reciprocating operation of a paper tray. Therefore, the slide head only needs to have a linear head portion. Of course, it may be a line shape, a complete line shape, or a staggered lattice arrangement. The head slide mechanism is
At least a rack provided on the paper tray side and a gear provided on the frame side may be provided, and various mechanisms can be adopted as a mechanism for slidingly moving the slide head by the rotational driving force of the gear. As an example, a gear mechanism may be employed, a mechanism driven by a pulling force of a wire, or a mechanism driven by a cam mechanism may be used.

[0010] The retracting mechanism shifts the relative positional relationship between the rack and the gear along the meshing surface. This meshing surface
In the case of a gear and a gear, this means a plane parallel to the axis of both gears, including a straight line parallel to the circumferential direction passing through the intersection of the two. Since the rack and the gear are moved along such a meshing surface, they are irrelevant to the moving direction in which the rack and the gear try to push out each other when they mesh with each other. As an example, the invention according to claim 2 is the printer device according to claim 1, wherein the retraction mechanism slides one or both of the rack and the gear linearly along a meshing surface. is there.

In the invention according to claim 2 configured as described above, when the rack and the gear mesh with each other on a certain arrangement plane, the engagement surface is in a direction orthogonal to this arrangement plane. Then, since the rack or the gear slides linearly along this orthogonal direction, meshing becomes impossible. Also,
As another example, according to a third aspect of the present invention, in the printer device according to the first aspect, the retracting mechanism rotatably supports the rack with the sliding direction as an axis and rotates the rack by a predetermined angle to mesh with the rack. It is configured to retreat by moving the part in an arc.

In the third aspect of the present invention, since the rack is rotatably supported around the sliding direction as an axis, the meshing portion of the rack moves in an arc. In this case, if it rotates from the meshing state with the gear, it can be said that although it slightly moves in the direction of repulsion with the gear, it generally moves along the meshing surface. In the case of retreating in the above-described repulsion direction, it is necessary to support on the rear side to resist the repulsion force at the time of meshing, but when moving along the meshing surface in this way, there is a fixed object on the rear side. , The support structure is simple and the influence of aging is small.

The timing at which the retracting mechanism makes the rack and the gear disengageable or engagable may be at least as long as it can be disengaged during the movement during printing. A specific example thereof is described in claim 4. According to the invention, in the printer device according to any one of claims 1 to 3, the retracting mechanism is set to a position where the rack and the gear can mesh with each other when the paper tray reciprocates in one direction. The rack and the gear are set at a position where they cannot mesh with each other when moving in the opposite direction.

[0014] In the invention according to claim 4 configured as described above, the paper tray is changed depending on the moving direction in the reciprocating operation. When the paper tray is moved in one direction, the rack and the gear are set at a position where they can mesh. When the gear is moved in the opposite direction, the rack and the gear are set at a position where they cannot mesh with each other.

[0015]

As described above, according to the present invention, the rack of the paper tray is meshed with the gear of the frame to drive the slide head, and during printing, the rack and the gear are retracted to a state where they cannot be meshed. As a result, the paper tray can be moved smoothly, so that it is possible to provide a printer device that can prevent the disturbance of the printed image while omitting the drive source of the slide head. In particular, since the retreat direction is movement along the meshing surface, the repulsive force when the rack and the gear mesh with each other can be supported by another structure,
The configuration can be simplified.

Further, according to the second aspect of the present invention, the configuration is simplified because of the linear sliding movement. Furthermore, according to the third aspect of the present invention, since the configuration is such that the rotary motion is performed, the configuration is simplified. Further, according to the fourth aspect of the present invention, only the disengagement or the engagement is possible according to the moving direction of the paper tray, and the configuration for making the determination to retract is simplified.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic plan view showing a printer according to an embodiment of the present invention.
Is shown by a schematic side view.

In FIG. 1, a frame 10 supports components and the like of the printer, and is fixed by screws to a case 11 showing only an outer frame. The frame 10 is formed in a substantially rectangular flat plate shape, and has two rails 12 on the upper surface in the longitudinal direction, and the tray 21 can slide along the rails. For convenience, in FIG. 1, the lower part of the paper is referred to as the front, the upper part of the paper as the rear, the left of the paper as the left, and the right of the paper as the right.

The tray 21 has an arm piece 21a extending leftward, and a wire 22 is fastened to the arm piece 21a. The wire 22 is stretched between a reversing pulley 23 rotatably supported by a forward portion of the frame 10 and a wire driving mechanism 24 fixed to the rear end of the frame 10 by screws. Same wire drive mechanism 2
4 allows driving in the normal rotation direction and the reverse rotation direction.
That is, the wire drive mechanism 24 includes a stepping motor 24a, a reduction gear 24b, and a take-up pulley 24c. The wire drive mechanism 24 turns the take-up pulley 24c forward and reverse to wind the wire 22 stretched around the reverse pulley 23. By performing picking and feeding, the tray 21 to which the wires 22 are fastened can be reciprocated back and forth. The paper tray 20 is constituted by these components.

In the present embodiment, the tray 21 is driven by the pulling force of the wire 22, but the tray 21 is driven by a belt, or driven by a rack and gears.
It may be driven by a cam mechanism or the like. Hooks 21b are formed at the left and right end portions and the rear end edge portion near the front end of the tray 21 so that the edge of the photographic paper placed on the tray 21 can be pressed down and fixed. Although a detailed configuration of the hook 21b is omitted, a driving piece is provided on the lower surface of the tray 21 so that the hook 21b can be driven by contacting a projection formed on the upper surface of the frame 10. That is, when the tray 21 moves to the front end position, they come into contact with each other to release the photographic paper, and at other times, the photographic paper is separated and sandwiched.

The frame 10 has side walls 13, 13 erected from right and left edges upward.
The slide head 30 is supported so as to straddle over the upper part. The slide head 30 is about 1 / the width of the tray 21.
About three thermal heads 31 are provided, and the thermal head 31 can be vertically moved by a vertical drive motor 32. Here, when the thermal head 31 is moved upward, it separates from the printing paper on the tray 21, and when it is moved downward, it comes into contact with the printing paper. In order to support the slide head 30 so as to be able to reciprocate in the left-right direction, two beams 33, 34 are supported between the side walls 13, 13, and the front beam 33 passes through the front side of the slide head 30, The rear beam 34 has a slide head 30
The tip portions of the split arms 35, 35 projecting rearward from the front end are fitted.

In this embodiment, the slide head 3
Although the beams 33 and 34 described above are used so that 0 slides in the direction perpendicular to the direction of movement of the tray 21, it can be changed as appropriate, such as by using a rail. Also, the frame 10 does not necessarily need to be directly supported by the frame 10, and may be configured to slide with respect to the case 11 and move in a predetermined direction when the frame 10 is combined. . Further, in the present embodiment, the thermal head 31 is used. However, a predetermined head according to the printing method may be used, and when moving up and down, the thermal head 31 is moved via a solenoid or the like. Deformable.

A take-up mechanism 41 is fixed to the left portion of the frame 10, and takes up a take-up ribbon 41a made of a metal flake with a predetermined take-up force in the left direction in the figure. The take-up ribbon 41a is connected to the slide head 30 supported between the side walls 13, 13, whereby the slide head 30 is constantly urged leftward in the figure. On the other hand, the right side of the frame 10 has a gear 42 below and a take-up reel 43 above.
3, a traction string 43a is wound up. Same traction string 43
The leading end of a is fastened to the slide head 30, and when the gear 42 is driven to rotate, the coaxial take-up reel 43 also rotates, and the traction string 43a is taken up. Then, the slide head 30 is moved rightward in the figure against the winding mechanism 41.

A wedge-shaped engaging projection 44 is formed at the front end of the slide head 30 so that the left end protrudes more than the right end. A lock piece 45 having a concave portion 45a that can be engaged with 44 is supported. The lock piece 45 is rotatably supported at the right end with respect to the frame 10, and the left end side is urged rearward by a spring piece 45b.
As described above, the thermal head 31
In order to scan the entire printing paper surface on the tray 21, the tray 21 must be reciprocated by sliding by the width of the thermal head 31, and the stop position of the thermal head 31 is initially Three locations are required, including the location. The recesses 45a are formed at positions where the engagement protrusions 44 face the three stop positions. That is, when the take-up reel 43 is rotationally driven to wind up the pulling string 43a, the slide head 3
0 moves rightward in the figure, but since the engagement protrusion 44 has a wedge shape protruding toward the left end side, the lock piece 45 naturally tries to be pushed forward as shown in FIG. With the right end as the fulcrum, the left end retracts forward. Further, the slide head 30 moves to the right,
When the next stop position is reached, the engagement projection 44 is moved to the next recess 45.
a, the locking piece 45 is pivoted rearward by the left end spring piece 45b, and the engaging projection 44 is
5a. Therefore, at this point, the winding of the pulling string 43a may be stopped, and the tray 21 may be reciprocated.
When it is finally desired to return the slide head 30 to the initial position, the tray 21 is moved to a position rearward than usual. Then, the release lever 46 is raised, and when the tray 21 is moved forward thereafter, the lock piece 45 is released.
Is pushed forward, and is pulled back to the left end by the winding mechanism 41. This process is shown in FIG. The take-up reel 43 is urged to take up the traction string 43a with a sufficiently weaker force than the take-up mechanism 41.
3a does not loosen.

The take-up reel 43 is rotationally driven by a gear 42 formed below the take-up reel 43. The gear 42 meshes with a movable rack 47 supported on the right side of the tray 21 to rotate. Is done. That is, tray 2
When the front rack 1 moves forward, the movable rack 47
And the same gear 42 is rotated. Therefore, tray 2
The slide movement of the slide head 30 described above is performed when the slide head 30 moves forward.

In the present embodiment, the head slide mechanism is constituted by the take-up mechanism 41, the gear 42, the take-up reel 43, the engagement projection 44, the lock piece 45, the release lever 46, the movable rack 47 and the like. Is composed. In this case, any configuration may be used as long as the slide head 30 is slid by the rotational driving force generated by the engagement between the movable rack 47 and the gear 42, and may be realized by a cam mechanism or the like.

The movable rack 47 meshes with the gear 42 when moving forward, but printing is performed only when the tray 21 moves rearward. Does not disturb the printed image. However, when the movable rack 47 meshes with the gear 42 when the tray 21 moves backward,
Smooth movement cannot be performed, and the printed image is disturbed. For this reason, the movable rack 47 is configured to retract with respect to the gear 42 at least when the tray 21 moves backward.

FIGS. 5 and 6 show a state where the movable rack 47 and the gear 42 mesh with each other, and FIGS. 7 and 8 show a state where they cannot be meshed with each other. The movable rack 47 is rotatably supported by a shaft 51 oriented in the reciprocating operation direction of the tray 21 with respect to the lower surface portion of the tray 21.
The connecting portion of the movable rack 47 with the coaxial core 51 is formed in a crank shape, and has a first support wall 52a bent upward from an edge of the movable rack 47, and a movable portion from the upper end of the first support wall 52a. A second support wall 52b is provided that is bent toward the side opposite to the rack 47. Movable rack 47
When the shaft receives the repulsive force from the gear 42,
Fully supported by In the crank-shaped portion, the repulsive force generates a rotational driving force in the clockwise direction with the axis 51 as a fulcrum. The crank shape itself supports the repulsive force because it is pressed against the side and resists.

On the other hand, in FIG. 5, it is possible to rotate in the counterclockwise direction, and by rotating in the same direction, the movable rack 47 retreats along the meshing surface with the gear 42 and becomes incapable of meshing. . A lock pin 53 rotatable in the plane is supported on the lower surface of the tray 21, and the lock pin 53 includes a lock arm 53a extending below the second support wall 52b. The lock arm 53a abuts on a portion of the second support wall 52b separated from the axis 51 at the initial position of the lock pin 53 shown in FIGS. Adhere to the lower surface. However, when the lock pin 53 rotates, the lock arm 53a moves toward the shaft center 51. At this time, a gap is generated because the thickness of the second support wall 52b is thin. .
However, as shown in FIG. 7, since the movable rack 47 itself is biased so that the spring 54 rotates counterclockwise, the movable rack 47 rotates by the amount of this gap.
As a result, the movable rack 47 separates from the gear 42 as shown in FIGS. That is, the lock pin 5
The movable rack 4 is rotated by rotating the movable rack 4 within a predetermined range.
7 can be meshed with the gear 42 or cannot be meshed. A hemispherical projection is formed on the upper end of the lock arm 53a, and a corresponding recess is formed on the lower surface of the second support wall 52b. It is kept stable.

The lock pin 53 is formed with an engagement arm 53b together with the lock arm 53a. Correspondingly, the upper surface of the frame 10 is brought into contact with the engagement arm 53b when the tray 21 is moved to a predetermined position. The contact projections 55 and 56 for rotating the lock pin 53 in contact therewith are formed. When the tray 21 moves to the rearmost end, the one contact projection 55 comes into contact with the engagement arm 53b from the rear surface side to rotate the lock pin 53 from the state shown in FIG. 8 to the state shown in FIG. , The other contact projection 56 is
Is moved from the front side of the engagement arm 53b to the lock pin 53 from the state shown in FIG. 6 to the state shown in FIG. It is formed in.

Therefore, when the tray 21 moves rearward, the lock pin 53 is in a state where the movable rack 47 is retracted from the gear 42, and the contact protrusion 55 is located at the rearmost position.
Abuts on the engagement arm 53b to rotate the lock pin 53, and the lock arm 53a displaces the movable rack 47 to a state where the movable rack 47 can mesh with the gear. When the tray 21 advances as it is, the movable rack 47 and the gear 42 mesh with each other, and the slide head 30 moves. When the slide head 30 comes to the frontmost position, the contact protrusion 56 contacts the engagement arm 53b. Then, the lock pin 53 rotates in the opposite direction, and the lock arm 53a displaces the movable rack 47 so that the movable rack 47 cannot mesh with the gear 42. Therefore, when the tray 21 advances next, the movable rack 47 and the gear 42 smoothly advance without meshing.

In the present embodiment, the retractable mechanism is constituted by making the movable rack 47 be able to move in an arc in this manner. However, the movable rack 47 and the gear 42 are retracted along the meshing surface. Any other configuration is possible. For example, the gear 42 may be retracted up and down, or the movable rack 47 may slide up and down. By the way, the movable rack 47 and the gear 4
It is also possible to adopt a configuration in which the two are retracted in a direction away from the meshing surface. However, in this case, the repulsive force between the movable rack 47 and the gear 42 must be supported by the movable portion, and the configuration is relatively complicated. On the other hand, when retreating along the meshing surface, there is an advantage that the repulsive force applied in the meshing state is easily supported.

Next, the operation of this embodiment having the above configuration will be described. At the time when the previous printing is completed, the tray 21 has moved to the front end position as shown in FIG. Also,
The slide head 30 is waiting at the left end position, and the movable rack 47 is retracted from the gear 42. To start printing, a cover (not shown) is opened, photographic paper is placed on the tray 21, and an operation switch (not shown) is turned on. Then, first, the tray 21 slightly moves rearward, whereby the hook 21b sandwiches the printing paper. At the same time, the vertical drive motor 32 of the slide head 30 is driven, and the thermal head 31 is driven downward to sandwich the photographic paper between the thermal head 31 and the tray 21. From this state, the printing control circuit (not shown)
To the wire drive mechanism 24
Is driven, and the tray 21 starts moving backward.

When the tray 21 moves to the vicinity of the rear end, it exceeds the printing range of the thermal head 31, and the print control circuit ends the transmission of the video signal, but moves it a little further backward. During this last movement, the engagement arm 53b of the lock pin 53 comes into contact with the contact protrusion 55 formed on the upper surface of the frame 10, and the lock pin 53 rotates slightly. Then, since the lock arm 53a pushes up the second support wall 52b of the movable rack 47 upward, the movable rack 47 rotates about the axis 51. That is, the state changes from the state illustrated in FIG. 7 to the state illustrated in FIG.

When the movable rack 47 shifts in this way, the stepping motor 24a starts to rotate in the reverse direction,
Begins to return to the front. Prior to this, the thermal head 31 has been returned upward. While the tray 21 is moving forward, the movable rack 47 meshes with the gear 42 to rotate the gear 42. The gear 42 is fixed to the take-up reel 43, and the take-up reel 43 starts taking up the pulling string 43a. Then, the slide head 30
Is pulled to the right in the drawing, and the
Pushes the lock piece 45 forward.

During this time, the tray 21 also moves forward, and when the engaging projection 44 enters the second concave portion 45a, the lock piece 4
5 is pushed back once. Immediately after this, the movable rack 4
7 is disengaged from the gear 42 and the slide head 30 is disengaged.
Is pulled back to the left by the winding mechanism 41. However, the engagement protrusion 44 is pressed to the left in a state of being inserted into the second concave portion 45a, and
0 means to wait at the second scanning position. Although vibration occurs while the slide head 30 is driven in this way, since printing is not being performed, the print image is not affected.

When the tray 21 returns to the front end, the engagement arm 53b of the lock pin 53 comes into contact with the contact protrusion 56, so that the lock arm 53a moves from the lower surface of the second support wall 52b toward the shaft center 51. It moves and the movable rack 47 is flipped up by the action of the spring 54. Thereafter, the tray 21 starts moving backward for the second operation,
At this time, as described above, the movable rack 47 is flipped up and does not mesh with the gear 42. In the same manner, when the third scan is performed, the release lever 46 is driven to rotate, and when the tray 21 moves forward, the lock piece 45 is pushed out halfway. It is pulled back to the standby position.

As described above, when the tray 21 is reciprocated back and forth on the upper surface of the frame 10 by the wire drive mechanism 24, the movable head provided on the right side of the tray 21 so as to sequentially slide the slide head 30 rightward. Rack 47
When the gear 42 supported by the frame 10 is rotated, the contact protrusions 55 and 56 formed at the front and rear end positions of the tray 21 and the engagement arm 53b of the lock pin 53 are brought into contact with each other. The movable rack 47 and the gear 42 do not mesh with each other during the backward movement during printing, but can be meshed only during the forward movement without performing printing. Can be smoothly moved to prevent disturbance of the printed image, and since the retreat direction is along the meshing surface, the repulsive force between the movable rack 47 and the gear 42 can be supported by a fixed structure, and the configuration is simplified. Can be

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a printer device according to an embodiment of the present invention.

FIG. 2 is a schematic side view of the printer device.

FIG. 3 is a schematic plan view showing a state in which a slide head is moving in the printer device.

FIG. 4 is a schematic plan view showing a state in which a slide head is returned to an initial position in the printer.

FIG. 5 is an enlarged sectional view of a retracting mechanism portion in a state where the movable rack and the gear are meshed.

FIG. 6 is a schematic plan view of a retracting mechanism portion in a state where the movable rack and the gear mesh with each other.

FIG. 7 is an enlarged cross-sectional view of a retracting mechanism in a state where the movable rack and the gear cannot mesh with each other.

FIG. 8 is a schematic plan view of a retracting mechanism in a state where the movable rack and the gear cannot mesh with each other.

FIG. 9 is an explanatory view showing an arrangement position of a contact protrusion and a contact state of a lock pin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Frame 20 ... Paper tray 30 ... Slide head 41 ... Winding mechanism 42 ... Gear 43 ... Winding reel 44 ... Engagement protrusion 45 ... Lock piece 46 ... Release lever 47 ... Movable rack 51 ... Shaft core 52a ... First Support wall 52b Second support wall 53 Lock pin 54 Spring 55, 56 Contact projection

Claims (4)

(57) [Claims] A frame, a paper tray supported reciprocally with respect to the frame, and on which a predetermined photographic paper can be placed, and a reciprocating direction of the paper tray with respect to the frame.
The sheet of paper on the paper tray to a direction substantially perpendicular to the
Is slidably supported in a direction parallel to the paper tray and abuts on the photographic paper placed on the paper tray, and scans and prints on the photographic paper with the sliding operation and the reciprocating operation of the paper tray. A slide head, comprising a rack provided on the paper tray side and a gear provided on the frame side, and the rack and the gears when the paper tray is moved in any one of reciprocating operations. And a head slide mechanism for generating a driving force to slide the slide head by sliding, and a movement operation in the opposite direction of the reciprocating movement of the paper tray.
Sometimes the rack and the said gear by shifting the relative positional relationship along the engagement surface and a retracting mechanism for the mesh disabled, moving operation when the above slide in the opposite direction of the sheet tray
A printing section using a print head . 2. The printer device according to claim 1, wherein the retracting mechanism linearly slides one or both of the rack and the gear along a meshing surface. 3. The printer device according to claim 1, wherein the retracting mechanism rotatably supports the rack with the sliding direction as an axis and rotates the meshing portion by an arc by rotating the rack by a predetermined angle. And a printer device for evacuation. 4. The printer according to claim 1, wherein the retracting mechanism is capable of engaging the rack and the gear when the paper tray reciprocates in one direction. And the rack and the gear cannot be engaged with each other when the rack is moved in the opposite direction.