JPH077179Y2 - Recording sheet holding device in recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a recording sheet holding device necessary for a recording device in which an image is recorded on a recording sheet wound and held on a platen roll by a recording head. Regarding the improvement of.

[Prior Art] As a conventional recording apparatus, there is one disclosed in Japanese Patent Laid-Open No. 58-162054. This is a heat-sensitive transfer type recording apparatus for color, and as shown in FIG. 6, it is provided with a thermal head 1 and a platen roll 2 arranged to face the thermal head 1, and is provided on the platen roll 2. Holding device 3
An ink donor in which the front end of the recording sheet 4 is held by a plurality of thermally sublimable inks are sequentially applied at predetermined intervals between the recording sheet 4 wound around the platen roll 2 and the thermal head 1. By inserting the film 6 and rotating the platen roll 2 a plurality of times,
The image information from the thermal head 1 is sequentially superposed and transferred onto the recording sheet 4 via each ink layer of the ink donor film 6 to obtain a color transfer image on the recording sheet 4. In FIG. 6, reference numerals 7 and 8 are a supply roll and a winding roll of the ink donor film 6.

In this type, the holding device 3 for holding the recording sheet 4 has a holding arm 11 whose tip is bent at a substantially right angle.
Is supported so as to be able to move forward and backward along the radial direction of the platen roll 2, and the holding arm 11 is biased toward the center of the platen roll 2 by a spring 12 to bend the bent portion 11a of the holding arm 11 and the platen roll. There is used one in which the leading end of the recording sheet 4 is sandwiched between the two surfaces.

[Problems to be Solved by the Invention] By the way, in such a conventional recording sheet holding device, as shown in FIG. 7, the recording sheet 4 is not responsive to the rotational force of the platen roll 4. In that case, a relatively large separating force (inertial force) acts in the circumferential direction of the platen roll 2, but in the conventional holding device for the recording sheet 4, the holding arm 11 is bent. Part 11
Since the front end of the recording sheet 4 is held along the circumferential direction of the platen roll 2 by a and the surface of the platen roll 2, the releasing force F in the removing direction of the recording sheet 4 directly affects the recording sheet. 4 will act on the holding part,
As a result, there is a problem in that the recording sheet 4 is incompletely held because the recording sheet 4 is easily removed. In particular, in the type in which the platen roll 2 is rotated a plurality of times to form one color image, if the holding position of the recording sheet 4 is incomplete and the holding position of the recording sheet is displaced, the transfer image is displaced. As a result, the image quality becomes extremely poor.

Further, in the above-described conventional recording sheet holding device, since the bent portion 11a of the holding arm 11 is arranged so as to project radially outward from the surface of the platen roll 2, it is possible to prevent interference with the thermal head 1. Therefore, the guide member 9 for temporarily retracting the thermal head 1 must be provided, and the number of parts of the recording apparatus increases correspondingly, which causes a problem that the configuration of the recording apparatus becomes complicated.

[Means for Solving Problems] The present invention has been made in view of the above problems, and it is possible to reliably hold a recording sheet while preventing the configuration of the recording apparatus from becoming complicated. The present invention provides a holding device for a recording sheet in the recording device.

That is, the present invention is a recording apparatus including a recording head and a platen roll arranged to face the recording head, winding the recording sheet around the platen roll and holding the recording sheet, and forming an image on the recording sheet by the recording head. As a premise, a recess portion extending along the axial direction of the platen roll is provided on a part of the platen roll surface, and one opening edge of the recess portion located in the entrance direction of the recording sheet is provided with respect to the circumferential direction of the platen roll. And a gripper for holding the leading end of the recording sheet, which is slanted along the slanted portion, is disposed in the recessed portion, and the base end of the gripper is rotatable. And an arm member having a protruding portion at a free rotation end that substantially opposes the inclined portion, and a recessed portion that is recessed from an extension surface of the inclined portion, and the arm portion is provided in the recessed portion. In which protrusions was shown and a receiving member for holding the leading end of the recording sheet is abutted accommodated in substantially U-shaped cross section.

In such a technical means, various types such as a thermal recording type and an electrostatic recording type can be used for the recording head as a schematic configuration of the recording apparatus, and the platen roll can be either solid or hollow. But it's okay. Also,
As for the recording sheet, when an indirect recording medium such as an ink donor film is used, it is only necessary that a recording image can be placed thereon, and when the above-mentioned indirect recording medium is not used, image information from the recording head is used. A thermal paper can be used for the thermal head, for example, which can directly reproduce the recorded image.

Further, as the configuration of the recessed portion, it is sufficient that at least an amount corresponding to the width dimension of the recording sheet is formed along the axial direction of the platen roll, and moreover, it has a portion appropriately recessed from the platen roll surface. If so, it does not matter whether it is a concave strip or a slit.

Further, the inclination angle of the inclined portion and the forming range thereof may be appropriately changed, but in consideration of the surface rigidity of the recording sheet and the like, the inclined portion is formed within a range in which the leading end of the recording sheet can be surely arranged in an inclined manner. There is a need to. In this case, if the surface rigidity of the recording sheet is high, there is a risk that the leading end bent portion of the recording sheet will float up. To prevent this rising up of the recording sheet more positively, press around the platen roll. It is desirable to dispose a roll or the like so that the bent portion of the leading end of the recording sheet is held along the surface of the platen roll.

Further, the gripper may be appropriately changed in design as long as it can hold the leading edge of the recording sheet. However, one of the grippers is a movable arm member and the other is a receiving member thereof, and the gripper of the recording sheet From the viewpoint of stabilizing the holding operation, it is desirable to have a structure in which the tip is clamped. Then, in order to hold the recording sheet more securely, it is designed to prevent the recording sheet from being separated by forming a high friction resistance portion such as an edge portion or a rough surface portion in the vicinity of the holding portion of the recording sheet. It is desirable to design to increase the holding power of the holding portion of the seat itself.

[Operation] According to the technical means as described above, the tip of the recording sheet is guided into the recess along the inclined portion formed at the opening edge of the recess, and the gripper having the predetermined structure, that is,
An arm member having a base end rotatably supported and a rotation free end having a projecting portion substantially facing the inclined portion, and a concave portion recessed from an extension surface of the inclined portion, the arm member being provided in the concave portion. The projecting portion of the recording sheet is abutted and held by a gripper including a receiving member that holds the front end of the recording sheet in a substantially U-shaped cross section. Only a part of the acting separating force corresponding to the inclination angle of the inclined portion acts, and the boundary edge portion between the inclined portion and the platen roll surface, the inlet side edge portion of the receiving member, and the arm member. The vertical force substantially orthogonal to the surface of the recording sheet locally rises at three points of the nipping portion by the protruding portions, and the frictional resistance against the separating force acting on the recording sheet increases.

In addition, since the gripper is disposed so as to be recessed in the recess when the recording sheet is held, there is no possibility that the gripper functions as an external protrusion protruding to the surface of the platen roll.

[Embodiment] Hereinafter, the present invention will be described in detail based on an embodiment shown in the accompanying drawings.

FIG. 1 shows a color thermal recording apparatus to which the present invention is applied. The specific structure of this thermal recording apparatus is as follows: a thermal head 1, a platen roll 2 arranged to face the thermal head 1, a holding device 3 for a recording sheet 4 provided on the platen roll 2, and the recording sheet 4. A press roll 5 pressed against the periphery of the platen roll 2 between the holding position and the position of the thermal head 1.
And a color ink donor film 6 (see FIG. 6) inserted between the recording sheet 4 wound around the surface of the platen roll 2 and held and the thermal head 1. From the viewpoint of weight reduction, the platen roll 2 includes a cylindrical roll core 2a having a plurality of hollow portions in the axial direction while leaving the support shaft portion along the axis, and an elastic layer provided on the surface of the roll core 2a. It is composed of 2b and.

In this embodiment, the holding device 3 for holding the recording sheet 4 is used.
As shown in FIG. 2, a recess 21 extending along the axial direction is provided on a part of the surface of the platen roll 2, and the slope of one opening edge of the recess 21 located in the entrance direction m of the recording sheet 4 is inclined. The part 22 is provided and the gripper 23 is provided in the recess 21.

More specifically, the recess 21 has a slit-like shape obtained by cutting off a part of the outer peripheral portion of the roll core 2a and the elastic layer 2b corresponding thereto, and corresponds to the width dimension of the recording sheet 4 to be used. It is formed with a certain length. The inclined portion 22 is arranged so as to be inclined by a predetermined angle θ, for example, 20 ° with respect to the approach direction m of the recording sheet 4, in other words, the circumferential direction of the platen roll 2.

The gripper 23 includes a gripper arm 24 and a gripper base 27. The gripper arm 24 is arranged at a plurality of positions at predetermined intervals in the longitudinal direction of the recess 21, and the base end of the gripper arm 24 is provided with a pivot 25 on the side facing the inclined portion 22 of the recess 21. The gripper arm 24 is rotatably supported, and a protruding portion 26 facing the inclined portion 22 is formed at the free rotation end of the gripper arm 24. The gripper base 27 is integrally provided along the longitudinal direction of the side surface of the recessed portion 21 on the side of the inclined portion 22, and the surface portion thereof has a recess for abuttingly accommodating the protruding portion 26 of the gripper arm 24. Article
28 is formed, and an edge portion 29 is formed at the opening edge of the concave strip 28 located near the inclined portion 22.

Further, the gripper arm 24 is appropriately opened / closed by the drive mechanism 30 shown in FIGS. 2 to 4 at the holding start position and the releasing position (corresponding to the holding start position in this embodiment) of the recording sheet 4. It has become. That is,
The drive mechanism 30 urges the gripper arm 24 in advance to the gripper base 27 side via the urging spring 31, and at the one end of the pivot 25 of the gripper arm 24, a rotating piece 32 protruding in the radial direction. At the same time, the guide roller 33 is rotatably attached to the tip of the rotating piece 32, and the gripper lever 34 is rotatably attached to a predetermined fixed portion located near the guide roller 33.
The distal end of the actuating rod 35a of the electromagnetic actuator 35 is connected to the proximal end side of 34, and the gripper lever 34 is biased by an urging spring 36 in the direction opposite to the operating direction (for example, the backward direction) of the operating rod 35a. The electromagnetic actuator 35
The gripper lever 34 is set to the grip position (shown by the solid line in FIG. 3) at the time of operation, and the gripper lever 34 is made to stand by at the release position (shown by the phantom line in FIG. 3) when the electromagnetic actuator 35 is not operated. On the other hand, when the trapezoidal riding cam 37 is fixed to the tip of the gripper lever 34 and the gripper lever 34 is set to the grip position, as shown by the one-dot chain line and the two-dot chain line in FIG. The guide roller 33 is abutted and guided along the riding cam 37 so that the rotating piece 32 is properly tilted, and the gripper arm 24 is opened and closed accordingly.
In this embodiment, the gripper lever 34 is
It is set to the grip position at the timing of holding the recording sheet 4 in the gripper 23 and at the timing of releasing the recording sheet 4 from the gripper 23 after the recording process is completed, and otherwise set to the release position.

Therefore, according to the recording sheet holding apparatus of this embodiment, when holding the recording sheet 4, the platen roll 2 is held with the gripper lever 34 set to the grip position.
And the gripper arm of the gripper 23.
The recording sheet 4 is gripped by the gripper arm when 24 is opened.
It may be fed between the 24 and the gripper base 27.

That is, when the platen roll 2 rotates while the gripper lever 34 is set to the grip position, the guide roller 33 abuts on the riding cam 37 and rides up, so that the rotating piece is rotated. 32 gradually falls, and the gripper arm 24 is opened accordingly. In this state, when the recording sheet 4 is fed to the holding device 3 portion along the circumferential direction of the platen roll 2, as shown in FIG. 5, the leading end portion 4a of the recording sheet 4 is moved to the gripper arm 24.
And the gripper base 27. After that, when the platen roll 2 rotates and the guide roller 33 completely rides over the hoisting cam 37, the position regulation of the rotating piece 32 is removed, so that the gripper arm 31 is biased by the biasing spring 31. 24 closes. At this time, the leading end 4a of the recording sheet 4 is held by the gripper 23 in the recess 21.

Since the leading end portion 4a of the recording sheet 4 held in this manner is inclined along the inclined portion 22 by the angle θ, the detaching force of the recording sheet 4 caused by the rotation of the platen roll 2 is F Then, a component force approximately cos θ times the detaching force F acts on the gripper 23, and
As the boundary portion s between the inclined portion 22 and the surface of the platen roll 2 is formed like an edge, the frictional resistance at the boundary portion s increases. Therefore, the substantial separation force of the recording sheet 4 acting on the gripper 23 portion becomes small, and the recording sheet 4 becomes difficult to separate from the gripper 23 portion by that amount. Further, in this embodiment, since the edge portion 29 is formed at the opening edge of the concave line 28 of the gripper base 27, the substantial separation force of the recording sheet 4 is further reduced by the amount of the frictional resistance, and the recording is further performed. The seat 4 is held securely.

In addition, in this embodiment, the gripper 23 is a recessed portion.
The gripper 23 does not function as an external projection protruding from the surface of the platen roll 2 when the recording sheet 4 is held, because the gripper 23 does not function as an external protrusion when the recording sheet 4 is held. There is no risk of the gripper 23 interfering with the thermal head 1. For this reason,
In order to prevent the interference between the gripper 23 and the thermal head 1, it is not necessary to use the guide member 9 as shown in FIG.

Further, in this embodiment, the leading end portion of the recording sheet 4 is
Since 4a is inclinedly arranged along the inclined portion 22 of the recessed portion 21,
In particular, in the case of a recording sheet 4 having a high surface rigidity such as thick paper or plastic film, the tip bent portion 4b of the recording sheet 4 may rise. However, in this embodiment, since the press roll 5 that is in pressure contact with the peripheral surface of the platen roll 2 is provided, the rising of the leading end bent portion 4b of the recording sheet 4 is effectively suppressed, and the recording sheet is 4 is wound and held in close contact with the surface of the platen roll 2. Therefore, there is no variation in the transfer rate of the ink due to the floating of the recording sheet 4, and the image information from the thermal head 1 is transferred onto the recording sheet 4 in a good state.

In the recording process in which the platen roll 2 rotates a plurality of times, the guide roller 33 and the riding cam 37 do not engage with each other and the gripper 23 does not open and close. There is no risk that the holding state will be released. Then, when a series of recording processes is completed, the gripper lever 34, which was in the standby position, is set to the grip position again, and the gripper lever 34 is engaged to engage with the gripper lever 34.
After the opening operation of 23 releases the holding state of the recording sheet 4, the recorded recording sheet 4 is peeled from the platen roll 2 surface by a sheet peeling means (not shown) and is accommodated in a sheet baffle (not shown). Of.

[Advantages of the Invention] As described above, according to the recording sheet holding device of the present invention, the holding portion of the recording sheet is provided with a unit according to the inclination angle of the recessed portion of the detaching force acting on the recording sheet. Of the above-mentioned inclined portion and the surface of the platen roll, the edge portion on the inlet side of the gripper receiving member, and the sandwiching portion by the protruding portion of the arm member of the gripper. The vertical force is increased locally to reduce the separation force of the recording sheet that acts on the recording sheet holding part, so that the recording sheet is more reliably held, such as preventing the recording sheet from being displaced. Can be

Further, since the gripper for holding the recording sheet is not arranged so as to project from the surface of the platen roll when holding the recording sheet, it is possible to prevent the gripper and the recording head from interfering with each other without any means. There is no concern that it will unnecessarily complicate itself.

[Brief description of drawings]

FIG. 1 is an explanatory perspective view showing an embodiment of a recording sheet holding device in a recording device according to the present invention, and FIG.
II-II sectional view, FIG. 3 is a schematic explanatory view showing a concrete example of the gripper drive mechanism in the embodiment, and FIG. 4 is IV in FIG.
FIG. 5 is an explanatory view showing an operating state of the holding device according to the embodiment, FIG. 6 is an explanatory view showing an example of a conventional recording sheet holding device, and FIG. FIG. [Explanation of Codes] (1) ...... Thermal head (recording head) (2) ...... Platen roll (3) …… Holding device (4) …… Recording sheet (21) …… Recess (22) …… Inclination Part (23) …… Gripper (24) …… Gripper arm (arm member) (27) …… Gripper base (receiving member) (29) …… Edge part (high friction resistance part)

Claims (2)

[Scope of utility model registration request] 1. A recording apparatus comprising a recording head and a platen roll arranged opposite to the recording head, wherein a recording sheet is wound around the platen roll and held, and an image is formed on the recording sheet by the recording head. , A part of the platen roll surface is provided with a recess extending along the axial direction of the platen roll, one opening edge of the recess located in the entrance direction of the recording sheet with respect to the circumferential direction of the platen roll In addition to providing a slanting portion, a gripper for holding the leading end of the recording sheet slanted along the slanting portion is disposed in the recess, and the gripper has a base end that is rotatable. An arm member that is supported and has a protrusion at its free end that substantially opposes the inclined portion, and a recessed portion that is recessed from the extended surface of the inclined portion, and the arm member protrudes into the recessed portion. Part recording sheet holding apparatus in a recording apparatus which is characterized in that is provided a receiving member for holding the leading end of the recording sheet is abutted accommodated in substantially U-shaped cross section. 2. A recording sheet holding device in a recording device according to claim 1, wherein the recording sheet contact portion of the receiving member is formed as a high friction resistance portion.