JPH089249B2 - Head mask retracting mechanism - Google Patents

Description

The present invention relates to a head mask retracting mechanism that can lock a head mask in a retracted state, and to provide a head mask retracting mechanism that can easily set an ink ribbon with a simple mechanism. For the purpose, in a serial printer, the front end is rotatably supported by a carrier, a head mask is connected in the middle, the other end has a first engaging portion, and the first elastic member urges the print head toward the print head. First locked by the first stopper
The lever and the L-shaped member are rotatably supported by the carrier at the corners, the horizontal portion engages with the first engaging portion, and the right-angled bending portion and the second engaging portion are provided at the tip of the first vertical portion. Is provided at a position corresponding to the home position, the upper end of which is rotatably supported by the device frame in a direction perpendicular to the rotation direction of the second lever, and engages with the second engaging portion. In length, the lower end is urged by the second elastic member in the direction in which the print head moves. When the print head is not at the home position, it is locked by the second stopper, and when the print head comes to the home position, A third lever whose lower end engages with the second engaging portion and rotates against the elasticity of the second elastic member, and when the print head is at the home position, presses the tip of the first horizontal portion to The lower end of the 3 lever is located above the right angle bend of the 2nd lever, Tsu to configure and to be engaged in the path.

[Industrial application field]

The present invention relates to a head mask retracting mechanism for a print head of a printer, and more particularly to a head mask retracting mechanism that can lock a head mask in a retracted state.

In a serial printer such as a wire dot printer, when the ink ribbon reaches the end of its density life, it is usually necessary to replace each cassette. The ink ribbon set has a narrow gap between the print head and the head mask (for example, 0.25 mm),
It is common to retract the head mask from the print head with a lever and widen the gap to insert the ink ribbon, but pressing the lever with one hand and setting the ink ribbon with the other hand makes operation difficult, A mechanism to facilitate this is desired.

[Conventional technology]

As shown in FIG. 4, in the wire dot printer, the print head 1a, the head mask 2a, and the ribbon cassette 3 are mounted on the carrier 4a, and the print head 1a is placed on the platen 5 and the ribbon cassette is placed on the print paper 6. The ink ribbon 30 and the head mask 3a are pulled out from each other and face each other.

The carrier 4a is slidably fitted to a guide shaft 7 arranged parallel to the platen 5, and a feed screw 8 parallel to the platen 5 is also screwed into the carrier 4a. The print head 1a can be reciprocated in the directions of arrows A and B in the figure by forward and reverse rotations of the motor M. Further, the printing paper 6 is transferred in the direction perpendicular to the drawing by a transfer mechanism (not shown).

The print head 1a includes a plurality of print magnets (not shown) for forming prints by dots.

With this configuration, the print head 1a prints on the print paper 6 while moving in the direction of arrow A together with the carrier 4a in response to a print command. When printing of one line is completed, a line feed is sent by the transfer mechanism.

Printing is performed in this manner, but in order to set the ink ribbon 30 in the gap between the tip of the print head 1a and the head mask 2a, a head mask retracting mechanism 10 for retracting the head mask 2a is provided. It is shown in FIG.

As shown in the front view and the side view of FIGS. 5A and 5B, the head mask retracting mechanism 10 is composed of a bracket 12a and a lever 16a.

The tip of the bracket 12a is rotatably supported by a support shaft 40 provided on the carrier 4a on the print head 1a side of the head mask 2a, and ribbon guides 13a and 13b are formed at intermediate positions. Further, the head mask 2a is connected so as to be located outside the ribbon guides 13a and 13b, and the engaging portion 14a is provided at the other end, and is biased toward the print head 1a by the spring 15a, so that the carrier 4a is provided. It is positioned by the stopper pin 41.

The lever 16a has a support shaft 4 with one end provided on the carrier 4a.
It is rotatably supported by 2, and the lower part of the intermediate part is engaged with the engaging part 14a of the bracket 12a, and the pressing operation surface 17 is formed at the other end.

Since it has such a configuration, as shown in FIG.
When the push-down operation surface 17 is pushed down, the lever 16a rotates about the support shaft 42, and the bracket 12a moves around the support shaft 40 as indicated by an arrow C.
Since it rotates in the direction, the head mask 2a retracts together with the ribbon guides 13a and 13b and the distance between the head mask 2a and the print head 1a increases, so that the ink ribbon 30 moves from the inside of the ribbon guides 13a and 13b to the front surface of the tip of the print head 1a. Can be set easily. The head mask 2a can be obtained by releasing the pressing on the pressing operation surface 17.
Rotates in the direction of arrow D and returns to the original position.

[Problems to be Solved by the Invention]

According to the above-mentioned conventional method, when setting the ink ribbon, the lever is pushed with one hand to retract the head mask from the print head to widen the gap, and the other hand is used to set the ink ribbon, which makes the operation difficult and troublesome. There is a problem.

It is an object of the present invention to provide a head mask retracting mechanism that can easily set an ink ribbon with a simple mechanism.

[Means for solving the problem]

FIG. 1 shows a principle configuration diagram of the present invention, in which (a) is a front view and (b) is a side view.

In the figure, 1 is a print head, 2 head mask, 4 is a carrier, 29 is a second stopper, 30 is an ink ribbon, 41
Is a first stopper, 12 has a tip rotatably supported by the carrier 4, the head mask 2 is connected to an intermediate position, and the first engaging portion 14 has an other end.
And a first lever 16 which is urged by the first elastic member 15 toward the print head 1 and locked by the first stopper 41, is formed in an L-shape, and is attached to the carrier 4 at the corners. It is rotatably supported, the midpoint of the horizontal portion 18 engages with the first engaging portion 14, and the tip of the vertical portion 19 has a right angle bending portion 20 and a second engaging portion 21.
A second lever 22 having a position corresponding to the home position of the print head 1, the upper end of which is rotatably supported by the device frame in a direction perpendicular to the direction of rotation of the second lever 16, When the print head 1 is not in the home position when the print head 1 has a length that engages with the second engaging portion 21 and the lower end is biased by the second elastic member 23 in the direction in which the print head moves, Second
When the print head 1 reaches the home position by being locked by the stopper 29, the lower end engages with the second engaging portion 21 and rotates against the elastic force of the second elastic member 23. 3 levers.

Therefore, when the print head 1 is in the home position, the lower end of the third lever 22 is disengaged from the engagement with the second engaging portion 21 by pressing the tip of the horizontal portion 18, and the right angle bending portion 20 is pressed.
The second lever 29 is located above the first lever 29 to lock the third lever 22.

[Action]

When the ink ribbon 30 is set between the tip of the print head 1 and the head mask 2, the print head 1 is located at the home position and the tip of the horizontal portion 18 of the second lever 16 is pushed down to obtain the first elasticity. The first lever 12 pivots against the elasticity of the member 15 and the head mask 2 descends, and the print head 1
There is a gap between the tip of the head mask 2 and the head mask 2. On the other hand, the vertical part 19
Rotation causes the upper end to move and the lower end of the third lever 22 to move to the second
When the second lever 22 is released from the engagement with the engaging portion 21, the second stopper 29 is rotated and locked, and the pushing of the tip of the horizontal portion 18 of the second lever 22 is released, The lower end is positioned above the right-angled bent portion 20 of the second engaging portion 1 to hold the position of the second lever 16, and the return rotation of the first lever 12 is locked.

Therefore, the gap between the tip of the print head 1 and the head mask 2 is locked with the gap left open, so that the ink ribbon 30 can be easily set.

When the setting is completed and the printing is started, the print head 1 mounted on the carrier 4 moves from the home position in the printing direction, and the first lever 12 and the second lever 16 move together. The lower end of the lever 22 of the second lever 22
Is released from the holding on the right-angled bent portion 20, that is, the lock is released, and the elasticity of the first elastic member 15 is restored, so that the first lever 12 and the second lever 16 are returned to their original positions and the head is moved. The position of the mask 2 returns to the normal state.

In this way, the head mask 2 can be locked in a normal state of being retracted from the tip of the print head 1 with a simple mechanism, so that the ink ribbon 30 can be easily set. The lock can be automatically released by moving the print head 1.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. The same reference numerals denote the same objects throughout the drawings.

The bracket 12a, the levers 16b and 22a, and the engaging portions 14a and 21 of FIG.
a, springs 15a, 23a, stopper 29a and stopper pin 41a
Is a first lever 12, a second lever 16, a third lever 22, a first engaging portion 14, a second engaging portion 16, and a third engaging portion 2 of FIG.
1, first elastic member 15, second elastic member 23, second stopper
29 and the first stopper 41, respectively.

As shown in the front view and the side view of FIGS. 2A and 2B, the head mask retracting mechanism 10a includes a bracket 12a and levers 16b and 22a.

The lever 16b is formed in an L shape, and the corners of the carrier 4a
Is rotatably supported by a support shaft 42 provided on the lower part of the horizontal part 18a, the lower part of the middle part of the horizontal part 18a is engaged with the engaging part 14a of the bracket 12a, and the pressing operation surface 17 is provided on the other end. A right-angled bent portion 20a and an engaging portion 21a are provided at the tip.

The lever 22a is formed in an inverted L shape and is provided at a position corresponding to the home position of the print head 1a, and its corner portion is rotated by the support shaft 24 in a direction perpendicular to the rotation direction of the lever 16b and to the device frame 25. The vertical portion 26 is movably supported and has a length such that the vertical portion 26 engages with the engaging portion 21a of the lever 16b.
A pressing operation portion 28 is formed at the tip of the. Also horizontal part
27 is upward in the figure by the spring 23a, that is,
When the lower end of the vertical portion 26 is biased in the moving direction of the carrier 4a and the print head 1a is not in the home position, it is held at a predetermined position by the stopper 29. And when the print head 1a arrives at the home position,
The lower end engages with the engaging portion 21a and rotates by the amount of movement of the engaging portion 21a against the elasticity of the spring 23a.

With such a configuration, as shown in the front view and the side view of FIGS. 3A and 3B, the ink ribbon
When the 30a is set between the tip of the print head 1a and the head mask 2a, the print head 1a is positioned at the home position, and the pressing operation surface 17 of the lever 16b is pressed to move the lever 16b.
Rotates in the direction of arrow E, the bracket 12a rotates in the direction of arrow C against the elastic force of the spring 15a, and the ribbon guide 13
The head mask 2a is retracted together with a and 13b, and the space between the tip of the print head 1a and the head mask 2a is opened.

On the other hand, when the upper end of the lever 22a moves and lowers a little due to the rotation of the vertical portion 19a, the lower end of the lever 22a is released from the engagement with the engaging portion 21a, rotates to a predetermined position in the arrow G direction, and is stopped by the stopper 29. Then, the right-angled bent portion 20a of the lever 16b is positioned substantially horizontally below the lower end of the lever 22a.

Then, when the depression of the operation depression surface 17 is released, the lever 22a
The lower end of the lever 16b is positioned and held on the right-angled bent portion 20a, and the return rotation of the lever 16b is locked.

Therefore, since the gap between the tip of the print head 1a and the head mask 2a remains open, use both hands to
Insert the ink ribbon 30 into the ribbon guide 13
It can be set on the tip of the print head 1a from the inside of a, 13b. When the pressing operation portion 28 is pressed when the setting is completed, the lever 22a rotates in the direction of the arrow H, and the lever 16b
The lever 16a is rotated in the direction of arrow F and the head mask 2a is rotated in the direction of arrow D by releasing the lock by the right-angled bent portion 20a of the print head 1a. Return to position.

When printing is started immediately after the ink ribbon 30a is set, if the printing operation is started without pressing the pressing operation unit 28, the bracket 4a, the lever 12a, and the lever 4a together with the carrier 4a.
Since 16b moves from the home position and the right-angled bent portion 20a of the lever 16b automatically comes off the lower end of the lever 22a,
The head mask 2a returns to the original position.

When the cover (not shown) of the device is closed, the lever
If a pressing portion is formed on the inner surface of the cover so as to press the pressing operation portion 28 of 22a, the lever 16b can be unlocked by closing the cover.

Therefore, after setting the ink ribbon 30a, the pressing operation unit 28
Even if you forget to press, the lock will be released without problems by starting printing or closing the cover.

In this way, since the head mask 2a can be locked and unlocked with the simple mechanism retracted from the tip of the print head 1a, the ink ribbon 30a can be easily set.

〔The invention's effect〕

As described above, according to the present invention, when the ink ribbon is set in the gap between the print head and the head mask, the head mask can be locked while retracted from the front surface of the print head. The setting work is extremely easy, and since the lock is automatically released when the printing is started, there is an effect that it is not necessary to release the lock by an operation.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention, FIG. 2 is a configuration diagram showing an embodiment of the present invention, FIG. 3 is an explanatory diagram of the embodiment, and FIG. 4 is an outline of a wire dot printer to which the present invention is applied. FIG. 5 is a configuration diagram showing a conventional example, and FIG. 6 is an explanatory diagram of the conventional example. In the figure, 1,1a is a print head, 2,2a is a head mask, 4,4a is a carrier, 12 is a first lever, 12a is a bracket, 14 is a first engaging portion, and 14a and 21a are engaging portions. , 15 is a first elastic member, 15a and 23a are springs, 16 is a second lever, 16b and 22a are levers, 18 and 18a are horizontal portions, 19 and 19a are vertical portions, and 20 and 20a are vertical bending portions, 21 is a second engaging portion, 22 is a third lever, 23 is a second elastic member, 29 is a second stopper, 29a and 41a are stoppers, and 41 is a first stopper.

Claims (1)

[Claims] 1. A platen, a print head (1) having a head mask (2) facing the platen with a gap and having a head mask (2) on the front surface, and mounting the print head (1) and moving the platen in parallel with the platen. And a carrier (4) for performing printing on a print medium set in the gap via an ink ribbon (30) set between the head mask (2) and the tip of the print head (1). In a printer for printing with a head (1), the print head (1) having a head mask (2) at its tip.
Side rotatably supported on the carrier (4), the head mask (2) is connected at an intermediate position, the other end has a first engaging portion (14), and a first elastic member. A first lever (12) biased by the (15) toward the print head (1) and locked by a first stopper (41); and an L-shaped carrier (12). 4) is rotatably supported, the midpoint of the horizontal portion (18) engages with the first engaging portion (14), and the right-angled bending portion (2) is attached to the tip of the vertical portion (19).
0) and a second lever (1) having a second engaging portion (21)
6) and a position corresponding to the home position of the print head (1), the upper end of which is rotatably supported by the device frame in a direction perpendicular to the rotational direction of the second lever (16). ,
The print head (1) has a length that engages with the second engaging portion (21), and the lower end is urged by the second elastic member (23) in the moving direction of the print head (1). When 1) is not in the home position, it is locked by the second stopper (29), and when the print head (1) arrives in the home position, the lower end is the second engaging portion (21). ) Is engaged with the second elastic member (23) to rotate against the elastic force of the second elastic member (23), and when the print head (1) is at the home position, By pushing down the tip of the horizontal portion (18), the lower end of the third lever (22) is disengaged from the second engaging portion (21), and is placed on the right-angled bending portion (20). A head mask retracting mechanism, characterized in that the head mask retracting mechanism is configured to be positioned and to lock the third lever (22) by the second stopper (29).