JPS61164877A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To enable a stop position of a head to be fixed while performing control of up-down shift of a printing head and control of take-up of an ink ribbon by a single controlling system, by a construction wherein a peripheral cam and an end cam of a cam wheel are provided with notched parts into which cam followers making sliding contact with the cams can be respectively engaged, at predetermined positions thereof. CONSTITUTION:A protuberant part 12 of the end cam 14 and a horizontal extension part 18 of the peripheral cam 20 are provided with the notched parts 13, 19 into which the first and second cam followers 58, 82 can be engaged, at substantially central positions thereof. When a DC motor 30 is stopped, the cam wheel 6 tends to continue rotating due to the inertia thereof, but when the notched part 19 comes to a position corresponding to the position of the second cam follower 82 and when the notched part 13 comes to a position corresponding to the position of the first cam follower 58, the cam followers 82, 58 are engaged respectively into the notched parts 19, 13, thereby stopping the cam wheel 6. Accordingly, the stop positions in the up-down shift of the head can be constantly fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to improvements in thermal transfer printers, and particularly relates to a thermal transfer printer that can perform ink-clean winding control and head up-down (separation from and pressure contact with paper) control in one system. .

[Prior art]

In general, in head sliding type printers such as thermal transfer printers, the up and down movement of the print head and ink, y
The winding operation of the winder has the following relationship. That is, when printing on paper, in-clean winding is performed while the print head is brought into pressure contact with the paper. However, the special number ζ, which does not print on the paper, releases the pressure contact between the print head and the paper, and no incremental winding is performed.

In this way, the up-down motion of the print head and the winding motion of the ink cleaner are interrelated.

However, in conventional thermal transfer printers, the up-down operation of the print head and the incremental winding operation are performed in separate systems. That is, such thermal transfer printers have separate bladder-down control systems and ink-clean winding control systems for the print head, resulting in a complicated structure and high manufacturing costs.

Therefore, recently, thermal transfer printers have been developed that can perform in-clean winding control and head up/down control in one system. Namely, this heat transfer! The link is provided with a cam wheel having a curved cam and an end cam, and this cam wheel is driven to control the ink generation winding according to the motion of the curved cam, and to control the up and down movement of the head according to the motion of the end cam. It is configured to perform control. However, in this conventional structure, a DC motor is used as a drive means for the cam wheel, so even if the drive of the DC motor is stopped, the cam wheel continues to rotate due to its inertia. The stopping positions of the circumferential cam and the end cam of the cam follower were not constant (therefore, the stopping position of the spatula r was not constant), causing malfunction.

〔the purpose〕

Therefore, an object of the present invention is to provide a thermal transfer printer that can perform up-down control of print head 0 and wind-up control of print head 0 in one control system, and can also keep the stop position of head 9 constant in order to eliminate the above-mentioned drawbacks. It's about doing.

〔composition〕

In order to achieve the above object, the present invention provides a cam wheel having a curved cam and an end cam and driven by a DC motor, and drives the cam wheel to wind up the ink cartridge according to the movement of the curved cam. In a thermal transfer printer configured to control the up and down movement of the head according to the movement of the end cam, a cam follower that slides on these cams is engaged at predetermined positions of the curved cam and the end cam of the Ti1l cam wheel. The purpose is to achieve the above object by providing a notch that allows the user to enter the device.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a plan view of the inner splint of a thermal transfer printer according to an embodiment of the present invention, and FIG. FIG. 3 is a longitudinal cross-sectional view of the layer shown in FIG. As shown in FIG. 2, a cam wheel 6 is fixed to the bottom plate 4 of the carino 2 and is rotatable by nine cam shafts 8. The cam wheel 6 includes a first end cam 14 having a flat portion 10 (FIG. 1) and a raised portion 12 on the end surface (upper surface), and a second end cam 14 having a circumferential surface portion 16 and a horizontally extending portion 18 on the outer periphery. A curved cam 20 serving as a cam is provided. The camshaft 8
(FIG. 2) is provided with a cam wheel gear 22, and as the cam wheel ear 22 rotates, the cam wheel 6 also rotates. Further, at a substantially central position of the raised portion 12 of the end cam 14 and a substantially central position of the horizontally extending portion 18 of the curved cam 20, a first
As shown in Fig. 2, @1. Notch 13 formed so that the second cam follower 58.82 can fit therein.
19 is provided.

A useful shaft 24 is fixed to the bottom plate 4. A first jT' wheel 28 that meshes with the cam wheel gear 22, and a worm 32 of a DC motor 30, which is a cam wheel driving means fixed to the bottom plate 4.
A worm wheel 34 that meshes with the worm wheel 34 (FIG. 1) is integrally fixed, a position detection plate 36 is fixed to the upper part of the worm wheel 34, and a shaft is rotatably attached to the large diameter portion 26 of the stepped shaft 24. be supported. The aforementioned cam wheel ear 22 and first gear 2
Since the gear ratios of the position detection plate 36 and the cam wheel 6 are the same, the amount of rotation between the position detection plate 36 and the cam wheel 6 is always the same.

As shown in FIG.
It has a notch 38 of about 60-170 degrees. A light emitting element 40 and a sensor 42 are provided facing each other above and below the outer periphery of the position detection plate 36, and the light emitting element 40 always emits light to the sensor 421, so that the position detection plate 36 rotates. The notch 38 of the position detection plate 36 is connected to the light emitting element 40.
When the light reaches between the light emitting element 40 and the sensor 42, the sensor 42 is turned ON, and when a portion of the position detection plate 36 other than the notch 38 passes between the light emitting element 40 and the sensor 42, the light is blocked and the signal from the sensor 42 is turned OFF. The position detection plate 36, the light emitting element 40, and the sensor 42 constitute a cam wheel position detection means.

A wire 4 fixed to the outside of the carino is attached to the stepped shaft 24.
4 has been rolled! - The gear 46 and the second gear 48 are rotatably supported integrally.

As the carriage 2 moves in the A direction as shown in FIG. 4, the wire 44 rises 7? , so this wire 44
The pulley 46 around which is wound rotates in the direction B, and the second gear 48 also rotates accordingly.

As shown in FIG. 1, a shaft 54 is supported between the right side plate 5o and the intermediate side plate 52 of the carriage 2, and an up-down motion transmission member 56 is fixed to the shaft 54. The up-down motion transmission member 56 is provided with a first cam follower 58, and the first cam follower 58 is in sliding contact with the end cam 14.

A head pressure contact member 62 is swingably provided between the shaft 54 and the left side plate 60 of the carriage 2. The head pressure contact member 62
The protrusion 64 engages with the up-down motion transmission member 56, and when the up-down motion transmission member 56 swings around the shaft 54, the head pressure contact member 62 also swings in the directions C and D in FIG. The moving head (not shown) is brought into pressure contact with the paper (not shown) or the head is released from the paper. The up-down motion transmission member 56 and the head pressure contact member 62 constitute a head swinging means.

As shown in FIGS. 1 and 3, the bottom plate 4 has a second vertical shaft 66.
is fixedly installed, and a second ear 4 is attached to the end of the second vertical shaft 66.
An idle gear 70 that meshes with both 8 and a link cassette driving gear 680 (described later) is rotatably provided, and a swinging member 74 to which a third vertical shaft 72 is fixed is swingably mounted on the second vertical shaft 66. movably pivoted. Third vertical axis 72
7 on the idle gear 70 and 76 side
A regeneration cassette driving gear 68 that meshes with both gears of the regeneration gear 78 is rotatably provided.

Second vertical shaft 66, rig cassette drive gear 68, idle gear 70. The third vertical shaft 72 and the swinging member 74 constitute an ink ribbon winding means.

The seven ears 78 are provided on a reel 80, and the reel 80 engages with the reso/take-up portion (not shown) of the female cassette 76, and when the friction gear 78 moves once, the reel 8o also rotates. As a result, the ink riser in the cassette 76 is wound up.

A second cam follower 82 that is in sliding contact with the curved cam 2o is rotatably provided at the bottom of the third vertical shaft 72. Second vertical axis 6
A spring 84 wound around 6 is provided to press against the third vertical shaft 72 and a vertical plate 86 provided on the bottom plate 4. Due to the bias of the spring 84, the second cam follower 82 is constantly brought into sliding contact with the curved cam 20.

Next, the effect will be explained. FIG. 1 shows the state of the carriage 2 when it is not printing. In this state, the first cam follower 58 provided on the up-down motion transmission member 56 is in contact with the flat portion 10 of the end cam 14, so the up-down motion The head pressure contact member 62, which engages with the transmission member 56, is retracted to a position as shown by the two-dot chain line in FIG. 3, and the head (not shown) is separated from the paper.

Additionally, a second cam follower 8 provided on the third vertical shaft 72
2 is in contact with the horizontal protruding portion 18 of the curved cam 20;
For this reason, the swinging member 74 moves back in the direction E in FIG. is canceled.

When the carriage 2 moves in the direction of FIG. −
Since it is wound around the rear gear 46, it rotates together with the second gear 48, and this rotation is transmitted to the idle gear 70 and the hook cassette drive ear 68, and the rear cassette drive gear 68 also rotates. , since the engagement between the female cassette drive gear 68 and the friction gear 78 on the reden cassette 76 side is released,
8 does not rotate, and therefore, the ink riser in the reden cassette 76 is not taken up.

Next, when printing, D
The O motor 30 is driven, and the driving force of the DC motor 30 is transmitted from the worm 32 to the worm wheel 34 supported by the large diameter portion 26 of the stepped shaft 24.
6 also rotates in the direction C in FIG. Further, the cam wheel 6 is rotated in the direction C in FIG. 3 by the cam wheel gear 22 meshing with the first gear 28. Since the gear ratio between the first ear 28 and the cam wheel gear 22 is 1:1, the position detection plate 36 and the cam wheel 6 are rotated by the same angle when the DC motor 30 is driven.

When the position detection plate 36 is rotated 100 to 120 degrees from the state shown in FIG. 1, the notch 38 of the position detection plate 36 is located between the light emitting element 40 and the sensor 42.

At this time, the cam wheel 6 also rotates about 100 to 120 degrees from the state shown in FIG. 1, and the first cam follower 58 comes into contact with the protrusion 12 of the end cam 14.

Therefore, both the up-down motion transmission member 56 and the spatula P pressure contact member 62 rotate in the direction C in FIG. 3, and the head comes into contact with the paper.

Also, since the m2 cam follower 82 comes into contact with the circumferential surface portion 16 of the curved cam 20, the swinging member 74 rotates slightly in the direction C in FIG. are engaged.

Then, when the carriage 2 moves in the direction of the middle man in FIG.
This rotation is transmitted to the idle gear 70 and the cassette driving gear 68, and the cassette driving gear 68 also rotates. At this time? Since the hook set driving ear 68 and the friction gear 78 on the regen cassette 76 side are meshed with each other, the friction gear 78 rotates. Therefore,
The ink clean in the reden cassette 76 is wound up.

Therefore, when the position detection plate 36 and the cam wheel 6 are both rotated about 100 to 120 degrees from the state shown in FIG.
Is the head pressed against the paper at the same time? Gear 68 for hook set drive? The ink cartridge is meshed with a seven-reaction gear 78 on the side of the printer cassette 76, and paper printing is performed by the head while the ink cartridge is wound up as the cartridge 2 advances.

As described above, when the position detection plate 36 is rotated approximately 100 to 120 degrees, the position detection plate 36 is rotated between the light emitting element 40 and the sensor 42.
6 is now located, and the light emitting element 40
The light emitted from the sensor 42 is not blocked and reaches the sensor 42, and the sensor signal is turned ON, and this signal is transmitted to the CPU (not shown). When the cpty receives a signal from the sensor 42, it stops driving the DC motor 30.

Therefore, during printing, the position detection plate 36 and the cam wheel 6 are
c1 In a state rotated by 100 to 120 degrees from the state shown in FIG. 1, the ink cleaner 2 is moved while the ink clean is wound up and the head is in pressure contact with the paper, so that the head performs printing.

Next, in order to shift from the printing state to the non-printing state again, the DC motor 30 is driven by a command from the CPU (not shown), and the position detection plate 36 and the cam wheel 6 are
is rotated again to the state shown in FIG. 11ζ. At this time, as mentioned above, the head and paper are separated, and The meshing between the hook set driving gear 68 and the friction gear 78 is released, and the ink I/N is not taken up.

Then, when the position detection plate 36 returns to the position shown in FIG. Transmit. cpu is sensor 42
When the signal from the DC motor 30 is received, the drive of the DC motor 30 is stopped.

However, in the structure of the present invention, when the drive of the DC motor 30 is stopped and corrected, the cam wheel 6 continues to rotate due to its inertia force, but the cutout provided on the horizontally extending portion 18 of the curved cam 20 When the position of the notch 19 corresponds to the position of the second cam 7 lower 82 and the end face cam 1
When the position of the notch 1ls13 of the raised portion 12 of No. 4 corresponds to the position of the first cam follower 58, the second cam follower 82 and the first cam 7 follower 58 correspond to the position of the notch 19.
．． 13, the cam wheel 6 is stopped by overcoming the inertial force.

Therefore, according to the structure of the present invention, the up and down stop positions of the head can always be maintained at a constant position.

〔effect〕

As explained above, according to the present invention, not only can the winding control of the InnoClean and the up and down control of the bottom P be performed in one system, but also the stop position of the head up and down can always be kept constant. This has the effect of providing a thermal transfer printer that can perform

[Brief explanation of the drawing]

FIG. 1 is a plan view of a caliper of a thermal printer according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view taken along 1-1 in FIG. 1, and FIG. 3 is a longitudinal sectional view taken along 1-1 in FIG. Front view, @4
The figure is an explanatory diagram showing the movement of the carriage. 6... Cam wheel, 13... Notch, 14... End cam, 19... Notch, 20... Circumferential surface cam, 3
0...DO motor, 58...ill cam follower,
82...Second cam follower.

Claims (1)

[Claims] A cam wheel having a first cam and a second cam and driven by a DC motor is provided, and the cam wheel is driven to drive the first cam.
In a thermal transfer printer, the ink ribbon winding is controlled according to the movement of the first cam, and the up-down of the head is controlled according to the movement of the second cam. At the predetermined position of the cam of 2,
A thermal transfer printer characterized in that a notch is provided into which a cam follower slidingly contacts these cams.