JPH053326Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a thermal head holding device in a barcode printer.

Prior Art In this type of thermal head, the thermal head is generally held by a head support that rotates about a fulcrum shaft, and this head support is attached to the platen side in order to bring the thermal head into resilient contact with the platen. Forced. The fulcrum shaft is attached to the frame, and is held by a plate fixed to the frame, for example, with a screw or the like, in order to prevent it from coming off in the axial direction.

Problems that the invention aims to solve On the other hand, the thermal head is a consumable item and needs to be replaced.When replacing the head, the head support body must be removed from the frame, but in order to do so, the plate must be removed from the frame using a tool. , workability is impaired. Although there are other means for preventing the fulcrum shaft from coming off, they all require a fixing member and therefore have the same problem.

This invention was made in view of the above points, and an object thereof is to provide a thermal head holding device that allows the thermal head to be replaced with a single touch without using any tools.

Means for Solving the Problems In this invention, the head support 7 is urged toward the platen 3 by a biasing member 24 on a fulcrum shaft 5 provided on the frame 1 in parallel with the platen 3, so that it can rotate freely. The locking body 22 is mounted and is displaced between a position where it is locked to the head support 7 and a position where it is not locked against the head support 7 against the urging force of the urging member 24. A first plate is fitted to both sides of the head mounting plate 17, which is provided on the frame 1 and to which the thermal head 16 is fixed, so as to be rotatable around the fulcrum shaft 5 and to be freely insertable and removable in a direction perpendicular to the axis of the fulcrum shaft 5. Notches 18 are formed in opposing surfaces of both sides of the head support 7 and both sides of the head mounting plate 17 so that they engage with each other when the head support 7 is extended toward the platen 3. The fulcrum shaft 5
A shaft 14 and a second notch 19 are provided which are released from the locked state when the head support 7 is rotated in a direction away from the platen 3 about the center.

Function: Therefore, when the locking body 22 is locked to the head support 7, the head support 17 is fixed at a fixed position where the thermal head 16 contacts the platen 3. In this state, the shaft 14 and the second notch 19
Therefore, the operation of removing the first notch 18 from the fulcrum shaft 5 and removing the head mounting plate 17 from the head support 7 in a direction perpendicular to the axis of the fulcrum shaft 5 is prohibited. When the locking body 22 is displaced and the locking state with the head support 7 is released, the head support 7 is rotated in a direction away from the platen 3 about the fulcrum shaft 5 with respect to the head mounting plate 17. In this state, the shaft 14 and the second notch 1
9 is removed, the first notch 18 is removed from the fulcrum shaft 5.
It becomes possible to remove the head mounting plate 17 from the head support 7 together with the thermal head 16 in a direction perpendicular to the fulcrum shaft 5.

Embodiment An embodiment of this invention will be described based on the drawings. The frame 1 has opposing members, and these members include a platen 2 and a feed roller 3 driven by a motor (not shown), a push roller 4 in contact with the feed roller 3, a fulcrum shaft 5, and a shaft. 6 has been constructed.

As shown in FIGS. 3 and 4, the head support 7
has a spring table arm 9 with a hole 8 formed therein, a spring table arm 10, a label take-out sensor 11, and a press stud 12, and has a hole on both sides that is rotatably fitted to the fulcrum shaft 5. 13 is formed, and a shaft 14 and another shaft 15 are prevented from moving in the axial direction by retaining rings and protrude from both sides.

As shown in FIG. 5, a first notch 18 and a second notch 19 are formed on both sides of the head mounting plate 17 to which the thermal head 16 is screwed.
The longitudinal directions of the first notch 18 and the second notch 19 are perpendicular to each other.

Thus, the head support 7 is rotatably held on the fulcrum shaft 5, and the head mounting plate 17 is attached to the first notch 1.
8 is fitted onto the fulcrum shaft 5, and the second notch 19 is engaged with the shaft 14, thereby being held on the head support body 7. The thermal head 16 is pushed by the press stud 12 biased by the spring 20, rotates about the fulcrum shaft 5, and comes into elastic contact with the platen 2. The head support 7 is biased toward the platen 2 by a spring 24, which is a biasing member, stretched between pins 23 erected on both sides of the frame 1 and a hole 8 of the spring table arm 9. It is fixed in place by 22. That is, the locking body 22 is rotatably held on the frame 1 by a shaft 6, and U-shaped notches 21 are formed on both sides thereof to engage with both ends of the shaft 15 of the head support 7.

In this configuration, a label (not shown) sent to the feed roller 3 and push roller 4 is printed between the platen 2 and the thermal head 16. In this state, the shaft 14 and the second notch 19 are locked, so the first notch 18 is removed from the fulcrum shaft 5 and the head mounting plate 17 is moved from the head support 7 to the axial center of the fulcrum shaft 5. Pulling out in a direction perpendicular to is prohibited.

When removing the thermal head 16, as shown in FIG. 2, the locking body 22 is rotated counterclockwise about the shaft 6 to release the head support 7, and the head is supported using the fulcrum shaft 5 as a fulcrum. Rotate the body 7 counterclockwise to separate the thermal head 16 from the platen 2, and in this state rotate the head mounting plate 17 clockwise about the fulcrum shaft 5 to separate the shaft 14 and the second notch 19. By disengaging from the thermal head 16, the head mounting plate 17 can be pulled out diagonally upward together with the thermal head 16.
By reversing this series of operations, the head mounting plate 1
7 together with the thermal head 16 and the head support 7
The head support 7 can be fixed in a fixed position relative to the platen 2 by the locking body 22. Therefore, the thermal head 16 can be replaced with one touch without using any tools.

Incidentally, shafts may be provided upright on both sides of the head mounting plate 17, and second notches to be engaged with these shafts may be formed on both sides of the head support body 7. In this case, as long as one end of the notches on the platen 3 side is open, the same purpose as in the embodiment described above can be achieved.

Effects of the invention As described above, in this invention, the head support is rotatably attached to the fulcrum shaft provided in the frame by being urged toward the platen side by the urging member, and the head support is latched to the head support. A locking body is movably disposed on the frame, and is fitted to both sides of the head mounting plate to which the thermal head is fixed so as to be rotatable about the fulcrum shaft and to be freely inserted and removed in a direction perpendicular to the axis of the fulcrum shaft. a first notch is formed, and a shaft and a second notch are disposed on opposing surfaces of both side surfaces of the head support and both side surfaces of the head mounting plate to be releasably engaged with each other. By displacing the locking body to release the head support and rotating the head in a direction away from the platen using the fulcrum shaft as a fulcrum with respect to the head mounting plate, the shaft and the second notch are locked. To release the state, remove the first notch from the fulcrum shaft, and pull out the head mounting plate together with the thermal head from the head support, so that the thermal head can be replaced with one touch without using any tools. It has the effect of

[Brief explanation of the drawing]

The drawing shows one embodiment of this invention.
The figure is a longitudinal side view showing the thermal head installed.
Figure 2 is a vertical side view showing the thermal head removed, Figure 3 is a side view of the head support, Figure 4 is a plan view of the head support, and Figure 5 is a side view of the thermal head and head mounting plate. It is. DESCRIPTION OF SYMBOLS 1... Frame, 2... Platen, 5... Fulcrum shaft, 7... Head support, 14... Shaft, 16...
Thermal head, 17...Head mounting plate, 18...
...first notch, 19...second notch, 22...locking body, 24...biasing member (spring).

Claims (1)

[Scope of utility model registration request] A head support is rotatably mounted on a fulcrum shaft provided on a frame parallel to the platen, and is urged toward the platen by a biasing member, and the head support is rotated against the biasing force of the biasing member. The frame is provided with a locking body that is movable between a position where the thermal head is locked and a position where it is not locked with the head support, and a locking body that is rotatable about the fulcrum shaft is attached to the head mounting plate to which the thermal head is fixed. A first notch is formed to be inserted and removed freely in a direction perpendicular to the axis of the fulcrum shaft, and the head support is placed on the platen side on the opposing surface of the head support and the head mounting plate. a shaft and a second notch that are locked to each other in the advanced state and released from the locked state when the head support is rotated in a direction away from the platen about the fulcrum shaft; A thermal head holding device characterized by: