JPH088823Y2 - Thermal printer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermal printer.

2. Description of the Related Art First, FIG. 5 shows a device disclosed in Japanese Utility Model Laid-Open No. 58-86360. This is the frame that holds the platen 50
A movable body 52 is vertically rotatably attached to a 51 by a support shaft 53, and a lock lever 54 for locking the movable body 52.
Is a rotatively attached structure, and one end of a leaf spring 56 holding a thermal head 55 is fixed to a movable body 52.

In this thermal printer, the leaf spring 56 causes the thermal head 55 to elastically contact the sheet 57 on the platen 50 for printing, and the lock lever 54 is rotated clockwise to move the movable body 52 to the thermal head. The paper 57 is set between the platen 50 and the thermal head 55 by retracting it together with 55.

Problems to be Solved by the Invention To supply voltage to the heating element of the thermal head 55,
Since the number of heating elements is large, the number of connecting wires is also large. In addition, since the thermal head 55 is held by the rotating movable body 52, a special holder is required to prevent the connection line from swinging. Further, in order to reduce the heat of the thermal head 55, a heat dissipation plate is needed. Further, although the movable body 52 functions as a head cover in FIG. 5, it is necessary to cover the thermal head 55 in order to prevent the risk of burns and the like. Therefore, the structure becomes complicated. In addition, place the paper on the platen.
When it is set between the thermal head 55 and the thermal head 55, a gap cannot be opened between the platen 50 and the thermal head 55 without removing the lock lever 54 and then rotating the movable body 52 upward.

Means for Solving the Problems A support shaft is rotatably provided on a frame to which a thermal head is fixed, and a pair of left and right support levers each having a recess opened on the thermal head side and engaging with the outer periphery of the shaft portion of the platen are provided. First urging means that rotatably fits to the support shaft and urges the support lever toward the thermal head is provided, and faces the outer periphery of the shaft portion of the platen on the opposite side of the recess. A pair of left and right release levers, each having a hook and a facing portion that faces the outer periphery of the shaft portion of the platen on the opposite side of the hook, are fixed to both ends of the support shaft, and the release lever is provided in a direction opposite to the biasing direction of the support lever. A second biasing means for biasing the release lever is provided.

By fixing the thermal head to the frame in the fixed state, it is possible to easily process the connection line to the thermal head. Further, the shaft portions at both ends of the platen are supported by the recesses of the left and right support levers, and the platen is pressed against the thermal head by the support levers biased by the first biasing means. Further, the release lever hook urged by the second urging means prevents the platen from falling out of the concave portion of the support lever, and further the release lever is rotated to retract the hook from the shaft portion of the platen. At that time, the shaft of the platen can be removed from the recess at the facing portion and separated from the thermal head.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 4 is an exploded perspective view, in which reference numeral 1 is a fixedly arranged frame, to which a horizontally long thermal head 2 is fixed by screws 3. A support shaft 5 is rotatably fitted in holes 4 formed on both sides of the frame 1. Further, a motor 6 is fixed on the right side of the frame 1. A pair of left and right support levers 7, 8 are rotatably fitted to both ends of the support shaft 5, and a pair of left and right release levers 9, 10 are fixed.
The release levers 9 and 10 and the support shaft 5 are fitted to each other in a relationship of a modified shaft and a modified hole. The support lever 7,
Reference numeral 8 denotes a platen 11 having recesses 12 which engage with shaft portions at both ends thereof via bearings 14, and both ends of a spring 13 serving as a first biasing means are fixed to the supporting levers 7, 8 and the frame 1. By doing so, the support levers 7 and 8 are urged toward the thermal head 2 together with the platen 11. The recess 12 is V
It is formed in a V shape and is opened on the thermal head 2 side. In addition, the left and right release levers
9 and 10 are hooks 16 facing the recess 12 and facing each other with a predetermined gap in the upper outer circumference of a small diameter portion 15 formed at both ends of the shaft portion of the platen 11, and the opposite side of the hook 16. And a facing portion 17 facing the bearing 14 is formed, and a handle 18 is formed on the right release lever 10. Reference numeral 19 is a drive gear directly connected to the motor 6, and a platen gear 20 meshed with the drive gear 19 is fixedly fitted to one end of the shaft portion of the platen 11. The bearing 14 of the platen 11 is held by the cover 21. The cover 21 is openably and closably held on the upper opening surface of the housing (not shown) of the printer. Further, the support shaft 5 is prevented from moving in the axial direction by a stopper 22 held on the side surface of the frame 1.

FIG. 1 shows the support levers 7 and 8 and the release lever.
It is a side view showing the assembly structure with 9,10, for the sake of explanation, the frame 1
The wall surface at the right end of is omitted. Further, the release levers 9 and 10 are urged by a spring 23 which is a second urging means in a clockwise direction opposite to the urging direction of the support levers 7 and 8.

In such a structure, as shown in FIG. 1, since the support levers 7 and 8 are biased counterclockwise about the support shaft 5 by the spring 13, the recesses 12 of the support levers 7 and 8 are formed. The platen 11 held by the bearing 14 is elastically contacted with the thermal head 2. Further, since the concave portion 12 is V-shaped, the position of the shaft center of the platen 11 is maintained at a fixed position.

When setting the paper between the thermal head 2 and the platen 11, the handle 18 of the right release lever 10 is pressed counterclockwise. By this operation, as shown in FIG.
Since the left and right release levers 9, 10 rotate integrally with the support shaft 5 in the counterclockwise direction about the shaft center of the support shaft 5, the hook 16 retracts to the side of the bearing 14, and the facing portion 17 Bearing
Push up 14. When the release lever 10 is released, the release levers 9 and 10 rotate together with the support shaft 5 in the clockwise direction by the force of the spring 23, as shown in FIG. In this way, by pressing one release lever 10 once, both ends of the platen 11 can be released and the platen 11 can be separated from the thermal head 2. This allows
It is possible to improve the operability when setting the paper.

When the paper is set, the cover 21 is opened in the state shown in FIG. After the paper is set, by closing the cover 21, the bearing 14 of the platen 11 descends while pushing the release levers 9 and 10 and the support levers 7 and 8 to both sides and elastically engages with the recess 12. That is, the normal use state shown in FIG. 1 is restored.

Further, since the thermal head 2 is held by the frame 1 capable of increasing the heat dissipation area, the heat dissipation effect can be promoted, it is not necessary to separately use a heat dissipation plate, and further, the head cover for covering the thermal head 2 can be used. There is no need, and since the thermal head 2 is fixed to the fixed frame 1, the connection line for voltage supply does not swing, and the structure for fixing the connection line can be simplified. , Support levers 7,8 and release lever
9 and 10 can be held by the single support shaft 5, whereby the structure can be simplified.

The shaft of the platen 11 is directly supported by the recess 12 of the levers 7, 8.
May be engaged by. In addition, the platen 11 is
You may make it push up the shaft part of directly. Further, the hook 16 may be engaged with the bearing 14.

Effect of the Invention Since the present invention is configured as described above, by fixing the thermal head to the frame in the fixed state, it is possible to facilitate the processing of the connecting wire to the thermal head, and the platen is The shaft is positioned and supported by the recesses of the left and right support levers, but the platen can be pressed against the thermal head by the support lever urged by the first urging means, and the release lever can be rotated. When retracted, the hook can be retracted from the shaft of the platen and the shaft of the platen can be removed from the recess at the opposite part.Therefore, by pressing one release lever once, both ends of the platen are released and the platen is released. Can be separated from the thermal head, which can improve the operability. Since it is held by a frame whose area can be increased, it is possible to promote heat dissipation, there is no need to use a separate heat dissipation plate, there is no need for a head cover that covers the thermal head, and the thermal head Is fixed to a fixed frame,
The connecting wire for supplying the voltage does not swing, the fixing structure of the connecting wire can be simplified, and further, the supporting lever and the release lever can be held by a single support shaft, whereby It has an effect that the structure can be simplified.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention.
1 is a side view showing a normal use state, FIG. 2 is a side view showing a state in which a release lever and a support lever lever are rotated, and FIG. 3 is a state in which the release lever and the support lever are returned. FIG. 4 is an exploded perspective view, and FIG. 5 is a side view showing a conventional example. 1 ... frame, 2 ... thermal head, 5 ... spindle,
7,8 …… Support lever, 9,10 …… Release lever, 11 ……
Platen, 12 ... Recess, 13 ... First biasing means, 16 ...
Hook, 17 ... Opposing part, 23 ... Second biasing means

Claims (1)

[Scope of utility model registration request] 1. A thermal head fixed to a frame,
A support shaft rotatably held by the frame, and a pair of right and left rotatably fitted to the support shaft and having a recessed portion that is opened on the thermal head side and engages with the outer periphery of the shaft portion of the platen. Support lever, a first biasing means for biasing the support lever toward the thermal head, a hook facing the outer periphery of the shaft portion of the platen on the opposite side of the recess, and the hook on the opposite side of the hook. A pair of left and right release levers having opposite portions facing the outer periphery of the shaft portion of the platen and fixed to both ends of the support shaft, and biasing the release lever in a direction opposite to the biasing direction of the support lever. A thermal printer comprising a second urging means.