JP3748969B2 - Thermal head opening and closing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal head opening / closing device, and more particularly to a thermal head opening / closing device that is installed in a thermal printer or the like and contacts and separates the thermal head from a platen roller.
[0002]
[Prior art]
In general, a thermal printer transfers a print medium such as a label or a tag between a platen roller and a thermal head and prints predetermined print information on the print medium. It is necessary to open between the platen roller and the thermal head for loading or maintenance. Further, in order to apply a predetermined pressure to the print medium in accordance with the printing operation, a head lock mechanism that holds the contact state between the platen roller and the thermal head is also necessary. It is also necessary to release the mechanism and set the head lock mechanism in its head holding state by a closing operation.
[0003]
However, in a conventional thermal printer or head opening / closing device, for example, a lever is operated to release the head lock mechanism and then another lever is operated to separate the thermal head from the platen roller. There are two stages of operations that are difficult to operate, and if you forget one of the operations, for example, the printing operation does not work properly, and the other mechanisms are unpredictably burdened. There is a problem that can be given.
[0004]
In addition, a transfer roller (for example, a driving roller and a driven roller) may be adopted as a transfer mechanism for transferring the print medium. However, when the print medium is loaded and maintained and inspected, the transfer roller portion needs to be opened and closed. If this opening / closing operation is added to the above-described thermal head opening / closing operation, a three-stage operation is required, and there is a problem that the opening / closing operation of the thermal head may cause troublesome and unexpected burdens.
[0005]
[Problems to be solved by the invention]
The present invention has been considered in view of the above problems, and provides a thermal head opening / closing device capable of bringing a thermal head into contact with and separating from a platen roller by operating a single operation lever. This is the issue.
[0006]
Another object of the present invention is to provide a thermal head opening / closing device capable of releasing and setting a head lock mechanism for contacting the thermal head with the platen roller and capable of contacting and separating the thermal head from the platen roller. To do.
[0007]
Another object of the present invention is to provide a thermal head opening / closing device capable of releasing and setting the print medium transfer mechanism as well as opening / closing the thermal head.
[0008]
It is another object of the present invention to provide a thermal head opening / closing device that can easily perform a printing medium loading operation and a maintenance / inspection operation for each portion.
[0009]
[Means for Solving the Problems]
That is, the present invention focuses on the fact that a single operating lever can be used to release and set the head lock mechanism of the thermal head, and to open and close the thermal head, and to split the operating force of the operating lever in two directions. A head support mechanism for supporting a thermal head for printing on a print medium transferred between the platen roller and an operation lever for rotating the head support mechanism to contact and separate the thermal head from the platen roller. And a head lock mechanism for holding the head support mechanism in a state in which the thermal head is in contact with the platen roller, and following the operation of the operation lever. Operation branch plate that can release the head holding state of the lock mechanism, and this operation branch With some linked to the rate, have a, a drive link capable of opening and closing the head support mechanism,
A roller link connected to the drive link and a roller bracket rotatably holding the printing medium transfer roller are provided, and the roller bracket can be opened and closed by the drive link. A thermal head opening and closing device.
[0010]
To enable opening and closing the roller bracket by the upper SL drive link, with opening and closing of the head locking mechanism and the head support mechanism, even opening and closing of the transfer roller can be performed simultaneously.
[0011]
In a state where the thermal head is separated from the platen roller by the operation lever, the transfer roller can be opened further, and only the transfer roller portion is opened more greatly in the opened state of the thermal head. be able to.
[0012]
A follower plate that follows the operation lever is provided between the operation lever and the operation branch plate, and a follower long window that engages the operation pin of the operation lever is formed on the follower plate. A play can be provided for the opening and closing operation by the lever.
[0013]
A head opening / closing window that engages with the operation lever side pin of the drive link is formed on the operation branch plate, so that the opening / closing timing of the head lock mechanism and the opening / closing timing of the head support mechanism can be appropriately controlled.
[0014]
The operation branch plate has a release plate capable of releasing the head holding state of the head lock mechanism, and the release plate is movable with respect to the operation branch plate to release and reset the head lock mechanism. Can be performed smoothly.
[0015]
In the thermal head opening and closing device according to the present invention, the operation branch plate follows the operation of the operation lever to release the head holding state of the head lock mechanism, and at the same time, the drive link connected to the operation branch plate is the head support mechanism. Can be opened and closed, so that the release of the head holding state and the open state of the thermal head can be realized by a single operation of the operation lever.
Of course, a single operation of the operating lever is sufficient for the closing operation in which the thermal head is brought into contact with the platen roller with a predetermined pressure.
[0016]
Further, when a mechanism for transferring the print medium by the transfer roller is adopted, if the drive link can be opened and closed with the roller bracket holding the print medium transfer roller rotatably, the operation lever can be opened and closed. With a single operation, it is possible to open and close the transfer roller as well as open and close the thermal head.
[0017]
Therefore, at the time of loading the print medium and the maintenance and inspection of the printer, it is possible to open and close necessary portions with a simple and simple operation, and to improve the operability.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Next, a thermal printer 1 equipped with a thermal head opening / closing device according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a side view of an essential part of a thermal printer 1. The thermal printer 1 includes a printer frame 2, a head support mechanism 4 that supports the thermal head 3, and a platen that is rotatably attached to the printer frame 2. It has a roller 5, a head lock mechanism 6, a thermal head opening / closing device 7, and a transfer roller 8.
[0019]
The thermal head 3 prints predetermined print information while the print medium P and the ink ribbon R transferred by the transfer roller 8 are sandwiched between the platen roller 5 and transferred.
The transfer roller 8 is configured by a drive roller 9 and a driven roller 10, and can open and close the driven roller 10 with respect to the fixed drive roller 9 and can be loaded with the print medium P, as will be described later.
[0020]
FIG. 2 is a schematic front view showing the relative relationship among the printer frame 2, the head support mechanism 4, the head lock mechanism 6, the thermal head support device 7, and the like, as viewed from the downstream side of the print medium P.
2 and 1, the head support mechanism 4 includes a head support frame 11 that supports the thermal head 3 and a frame that is pivotally supported so as to open and close the head support frame 11. And a rotating shaft 12.
[0021]
The platen roller 5 sandwiches the print medium P and the ink ribbon R between the thermal head 3 and enables printing along with the transfer.
[0022]
The head lock mechanism 6 holds the contact pressure between the thermal head 3 and the platen roller 5 within a predetermined range and maintains the contact state between them. A projecting head lock collar 13 and 14 and a pair of head lock levers 15 and 16 each having a tip formed in the shape of a scissors so as to engage with the head lock collars 13 and 14, respectively. Have.
[0023]
The head lock levers 15 and 16 can be rotated integrally around a common lock lever rotation shaft 17, and the head lock levers 15 and 16 are locked in a direction (counterclockwise in FIG. 1) to be engaged with the head lock collars 13 and 14. A locking torque spring 18 for biasing the levers 15 and 16 is provided.
A release collar 20 is provided at the lower end of the head lock lever 15 located on the back side (the left side in FIG. 2) of the thermal printer 1, and the thermal head opening / closing device 7 (the operation branch plate 23 and its release plate 30). By operating the release collar 20, the head lock mechanism 6 can be released (described later in connection with the thermal head opening / closing device 7).
[0024]
The thermal head opening / closing device 7 according to the present invention includes an operation lever 21, a follower plate 22, an operation branch plate 23, a drive link 24, and a roller opening / closing mechanism 25.
[0025]
As shown in FIG. 2, the operation lever 21 is provided on the front side of the thermal printer 1 so as to be rotatable around an operation lever rotation shaft 26. By operating the operation lever 21, the thermal lever 21 The head 3 and the platen roller 5 are contacted / separated, the head lock mechanism 6 is released / set, and the roller opening / closing mechanism 25 is opened / closed.
[0026]
The follower plate 22 is rotated around the plate rotation shaft 27 so as to follow the opening / closing operation of the operation lever 21, and the “く” -shaped follower length with which the operation pin 28 of the operation lever 21 is engaged. A window 29 is formed. The play of the operation lever 21 is secured by loosely fitting the operation pin 28 to the long window 29 for follow-up.
[0027]
The operation branch plate 23 is located on the far side opposite to the follower plate 22 on the near side. The operation branch plate 23 rotates integrally with the follower plate 22 around the plate rotation shaft 27 and is connected to the operation branch plate 23. A release plate 30 that is movable is provided.
The release plate 30 is capable of releasing and setting the head holding state of the head lock mechanism 6 by contacting and separating from the release collar 20 of the head lock lever 15. That is, the release plate 30 has a flat portion 30A and a curved surface portion 30B that contact the release collar 20, and forms a pair of guide windows 32 with which the pair of guide pins 31 of the operation branch plate 23 are engaged. A compression spring 33 that biases 30 in the direction of engagement with the release collar 20 is provided.
[0028]
The drive link 24 opens and closes the head support mechanism 4 and the roller opening and closing mechanism 25. The drive link 24 is rotatable around the same frame rotation shaft 12 as the head support mechanism 4, and has four arms, that is, The operation lever side arm 34, the head side long arm 35, the head side short arm 36, and the roller side arm 37 are connected to the operation branch plate 23, the head support mechanism 4 and the roller opening / closing mechanism 25 at the respective arm tips. ing.
[0029]
That is, the operation lever side pin 38 at the distal end portion of the operation lever side arm 34 is engaged with the head opening / closing window 39 of the operation branch plate 23, and the head side pin 40 at the distal end portion of the head side long arm 35 is engaged with the head support mechanism 4. The head side screw 41 at the tip of the head side short arm 36 is engaged with the head support frame 11 of the head support mechanism 4, and the roller side pin at the tip of the roller side arm 37 is engaged. 42 is engaged with the roller link 43.
Note that the head opening / closing window 39 of the operation branch plate 23 has a substantially triangular shape, and ensures operation of the operation lever side pin 38 of the operation lever side arm 34, as well as the head lock mechanism 6 and the head support mechanism 4. The opening / closing timing is made appropriate, and the locking operation of the head lock mechanism 6 when the head support mechanism 4 is closed is ensured.
[0030]
The roller opening / closing mechanism 25 includes the roller link 43, a bracket link 44, and a roller bracket 45.
The bracket link 44 connects the roller link 43 and the roller bracket 45.
The roller bracket 45 rotatably holds the driven roller 10 of the transfer roller 8.
The roller link 43 is formed with a “<”-shaped roller opening / closing long window 46, and the roller opening / closing pin 47 of the bracket link 44 is engaged with the roller opening / closing long window 46.
[0031]
The bracket link 44 and the roller bracket 45 can rotate integrally around a common bracket rotation shaft 48.
[0032]
The opening and closing of the thermal head 3 and the opening and closing of the transfer roller 8 (driven roller 10) in the thermal printer 1 and the thermal head opening / closing device 7 having such a configuration will be described with reference to FIGS.
FIG. 3 is a main part side view showing an open state of the thermal head 3 and the driven roller 10, and FIG. 4 is a main part side view showing a state in which the driven roller 10 (roller bracket 45) is further opened.
In the closed state shown in FIG. 1, when the operation lever 21 is rotated around the operation lever rotation shaft 26 in the clockwise direction in the drawing, the operation pin 28 of the operation lever 21 moves into the tracking long window 29 of the tracking plate 22. The follower plate 22 is rotated counterclockwise around the plate rotation shaft 27 while moving slightly.
[0033]
The rotation of the follower plate 22 is transmitted to the operation branch plate 23 via the plate rotation shaft 27, and the operation branch plate 23 also rotates counterclockwise around the plate rotation shaft 27. The release plate 30 pushes the release collar 20 of the head lock lever 15 leftward at the tip of the flat portion 30A.
[0034]
Accordingly, the head lock lever 16 integrated via the head lock lever 15 and the lock lever rotating shaft 17 is moved around the lock lever rotating shaft 17 against the urging force of the locking torque spring 18 as shown in FIG. The head lock levers 15 and 16 are disengaged from the head lock collars 13 and 14 of the head support mechanism 4 together.
After the head lock levers 15 and 16 are disengaged from the head lock collars 13 and 14, the head lock levers 15 and 16 are returned to their original positions by the urging force of the locking torque spring 18 and wait for the closing operation of the head support mechanism 4. Become.
[0035]
Simultaneously with the release operation of the head lock mechanism 6, the roller side arm 37 of the drive link 24 is pushed leftward in the head opening / closing window 39 by the counterclockwise rotation of the operation branch plate 23, and the drive link Since the head 24 rotates clockwise around the frame rotation shaft 12, the head support frame 11 of the head support mechanism 4 integrated with the drive link 24 at the head side pin 40 and the head side screw 41 is also clockwise. The thermal head 3 is moved away from the platen roller 5, and the ink roller R and the print medium P can be inserted therebetween.
[0036]
Simultaneously with the operation enabling the insertion, the roller link 43 connected to the drive link 24 and the roller side pin 42 is moved rightward in FIG.
Since the roller link 43 is connected to the bracket link 44 by the roller opening / closing pin 47, the bracket link 44 and the roller bracket 45 rotate clockwise around the bracket rotation shaft 48, and the transfer roller 8 is driven. The roller 10 is separated from the drive roller 9 (the state shown in FIG. 3 as described above).
[0037]
From this state, as shown in FIG. 4, the bracket link 44 is moved so that the roller opening / closing pin 47 of the bracket link 44 is moved along the roller opening / closing long window 46 of the roller link 43 separately from the operation lever 21. Alternatively, the driven roller 10 can be further separated from the driving roller 9 regardless of the opened state of the thermal head 3 by further rotating only the roller bracket 45 in the clockwise direction.
Therefore, the transfer roller 8 can be opened while the thermal head 3 is separated from the platen roller 5 by the operation lever 21, and the printing medium P can be loaded or maintained easily. can do.
[0038]
Since the tracking plate 22 is formed with a tracking long window 29 and the operation branching plate 23 is formed with a head opening / closing window 39, when the head support mechanism 4 is opened by operating the operation lever 21, the head lock mechanism 6 is firstly opened. Then, each part can be operated at such a timing that the head support mechanism 4 is released with a slight delay.
[0039]
If the operation lever 21 is rotated counterclockwise in FIG. 1 after the ink roller R and the printing medium P have been loaded or maintained, the head support mechanism 4 is closed by the operation opposite to that described above. The thermal head 3 comes into contact with the platen roller 5 with a predetermined pressure, the head lock mechanism 6 is set, and the transfer roller 8 is set.
When returning from the state of FIG. 3 to the state of FIG. 1, the head lock collars 13 and 14 come into contact with the top ends of the head lock levers 15 and 16 against the urging force of the locking torque spring 18. Is slightly rotated in the clockwise direction and moved to engage the hand-shaped portion of the heel.
Further, at this time, the operation branch plate 23 rotates clockwise around the plate rotation shaft 27, but the curved surface portion 30B of the release plate 30 comes into contact with the release collar 20, and a pair of guide pins of the operation branch plate 23 31 moves in the pair of guide windows 32 against the urging force of the compression spring 33, and the release plate 30 returns to the state shown in FIG.
[0040]
【The invention's effect】
As described above, according to the present invention, the operation branch plate is operated in relation to the operation lever, the head lock mechanism is released / set by the operation branch plate, and the head support mechanism is opened / closed by the drive link connected to the operation branch plate. Therefore, a necessary mechanism can be opened and closed by a single operation of the operation lever, and a thermal printer excellent in safety and operability can be obtained. In addition, the roller opening / closing mechanism can be related to the operation of the operation lever, and the transfer roller can be opened and closed simultaneously with the opening and closing of the head lock mechanism and the head support mechanism. It can be.
[Brief description of the drawings]
FIG. 1 is a side view of a main part of a thermal printer 1 equipped with a thermal head opening / closing device 7 according to an embodiment of the present invention.
FIG. 2 is a schematic front view showing the relative relationship among the printer frame 2, the head support mechanism 4, the head lock mechanism 6, the thermal head support device 7 and the like, as viewed from the downstream side of the print medium P.
FIG. 3 is a side view of the main part showing the opened state of the thermal head 3 and the driven roller 10;
4 is a side view of an essential part showing a state where the driven roller 10 (roller bracket 45) is further opened. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Thermal printer 2 Printer frame 3 Thermal head 4 Head support mechanism 5 Platen roller 6 Head lock mechanism 7 Thermal head opening / closing device of thermal printer 1 (embodiment)
8 Transfer roller 9 Drive roller 10 Driven roller 11 Head support frame 12 Frame rotation shafts 13, 14 Pair of head lock collars 15, 16 Pair of head lock levers 17 Lock lever rotation shaft 18 Locking torque spring 20 Release collar 21 Operation Lever 22 Tracking plate 23 Operation branching plate 24 Drive link 25 Roller opening / closing mechanism 26 Operation lever rotating shaft 27 Plate rotating shaft 28 Operation pin 29 "U" shaped tracking long window 30 Release plate 30A Flat portion of release plate 30 30B Curved portion 31 of release plate 30 A pair of guide pins 32 A pair of guide windows 33 Compression spring 34 Operation lever side arm 35 of drive link 24 Head side long arm 36 of drive link 24 Head side short arm 37 of drive link 24 Drive Link 24 roller Side arm 38 Operation lever side pin 39 Head opening / closing window 40 Head side pin 41 Head side screw 42 Roller side pin 43 Roller link 44 Bracket link 45 Roller bracket 46 “L” shaped roller opening / closing window 47 Roller opening / closing pin 48 Bracket rotation axis P Printing medium R such as label or tag Ink ribbon of printing medium P

Claims (5)

A head support mechanism that supports a thermal head that performs printing on a print medium transferred between the platen roller and the platen roller;
A thermal head opening and closing device having an operation lever that contacts and separates the thermal head from the platen roller by rotating the head support mechanism;
A head lock mechanism for holding the head support mechanism in a state where the thermal head is in contact with the platen roller;
An operation branch plate that follows the operation of the operation lever and can release the head holding state of the head lock mechanism;
With some linked to the operation branch plate, have a, and openable drive linking the head supporting mechanism,
A roller link connected to the drive link and a roller bracket that rotatably holds the transfer roller for the print medium are provided, and the roller bracket can be opened and closed by the drive link. A thermal head opening and closing device. 2. The thermal head opening and closing device according to claim 1 , wherein the transfer roller can be opened while the thermal head is separated from the platen roller by the operation lever . A follow-up plate that follows the operation lever is provided between the operation lever and the operation branch plate, and a follow-up long window that engages an operation pin of the operation lever is formed on the follow-up plate. The thermal head opening and closing device according to claim 1 . 2. The thermal head opening / closing device according to claim 1 , wherein a head opening / closing window for engaging with an operation lever side pin of the drive link is formed on the operation branch plate . 2. The operation branch plate includes a release plate capable of releasing the head holding state of the head lock mechanism, and the release plate is movable with respect to the operation branch plate. Thermal head opening and closing device.

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