JPH0541822U - Platen gear adjustment device - Google Patents

Abstract

(57) [Summary] [Configuration] The printer unit that holds the print head is
Holds so that it can move automatically depending on the thickness of the media passing between the printhead and the platen. [Effect] When the thickness of the medium fluctuates, the gap between the print head and the medium can be maintained at an appropriate value according to the thickness, so that problems such as stains on printing and poor conveyance of the medium can be prevented. Printing can always be performed in a normal state without any occurrence.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a platen gap adjusting device for a printing device, particularly a printing device that prints on a medium having a non-uniform thickness.

[0002]

[Prior Art]

 Among the printing devices, the conventional printing device that prints on a medium having a non-uniform thickness particularly has a mechanism for detecting the thickness of the medium in order to adjust the platen gap. The actuator is operated according to the information from the actuator to drive the platen to secure an appropriate gap between the platen and the print head, or the platen is fixed and the print head is fixed by a spring. The print head is evacuated according to the thickness of the medium.

[0003]

[Problems to be solved by the device]

 In the former case where the platen gap adjusting means of the conventional printing apparatus as described above drives the platen by the actuator, once the platen gap is adjusted, printing is performed in the state of the platen gap until the next adjusting time. Therefore, when a medium with a non-uniform thickness is mounted, printing is performed with a non-uniform gap between the platen and the print head, which has the drawback of degrading print quality. .

Further, in the latter case where the platen is fixed and the print head is biased toward the platen by a spring, printing is performed while the print head is constantly pressed against the medium, and therefore the medium is not conveyed. It has the disadvantage of high resistance and inability to print at high speed.

[0005]

A platen gap adjusting device of the present invention is a medium thickness detecting mechanism for detecting the thickness of a medium passing between a print head and a platen provided facing the print head. Section, an actuator that drives the platen so that the gap between the print head and the platen is maintained at an appropriate value based on information from the medium thickness detection mechanism section, and the print head is mounted. A card holder attached to the carriage at the position of the tip of the print head; a lock lever provided at the tip of a printer frame rotatably held by a first guide shaft that holds the carriage and is fixed to the frame; A lock stud that engages with the lock lever and a spring that urges the lock stud toward the platen are provided.

[0006]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing an embodiment of the present invention.

In FIG. 1, a print head 2 and a card holder 3 are attached to a carriage 1, and during printing, the carriage 1 slides along guide shafts 5 and 6 to perform a spacing operation. . A platen 4 is provided facing the print head 2. The guide shaft 6 is fixed to the printer frame 8, and the guide shaft 5 is fixed to the frame (not shown). The printer frame 8 is attached so as to be able to rotate about the guide shaft 5, and the movement of the platen 4 in the direction (arrow C direction) is restricted by the stopper 7. The movement of the printer frame 8 in the direction of the print head 2 (direction of arrow D) is restricted by the lock stud 10 and the lock lever 9 engaged with the lock stud 10. The rock stud 10 is biased in the direction of arrow C by a spring 11.

The platen 4 is an actuator (not shown) so as to keep an appropriate gap between the platen 4 and the print head 2 according to the thickness of the medium 12 a detected by a medium thickness detection mechanism (not shown). ) Driven by. When the print head 2 is printing with a gap corresponding to the thickness of the medium 12a between the platen 4 and the platen 4, the medium 12a is conveyed and the seal stamp 12b comes to the position of the print head 2. The holder 3 is pushed by the medium 12a, and the lock stud 10 moves in the direction of arrow D against the force of the spring 11. As a result, the entire printer unit 13 including the printer frame 8 is retracted, and the gap between the print head 2 and the medium 12a is automatically maintained at a proper value. Therefore, it is possible to perform printing in a normal state without causing problems such as stains on printing and poor conveyance of the medium. When the seal stamp 12b passes the position of the print head 2, the printer unit 13 returns to the original state, and the portion of the medium 12a without the seal seal 12b is printed with an appropriate gap.

[0010]

[Effect of the device]

 As described above, the platen gap adjusting device of the present invention holds the printer unit, which holds the print head, so that it can be automatically moved according to the thickness of the medium passing between the print head and the platen. By doing so, when the thickness of the medium fluctuates, the gap between the print head and the medium can be maintained at an appropriate value according to the thickness. There is an effect that printing can always be performed in a normal state without causing a problem.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

[Explanation of symbols]

 1 Carriage 2 Print Head 3 Card Holder 4 Platen 5 Guide Shaft 6 Guide Shaft 7 Stopper 8 Printer Frame 9 Lock Lever 10 Lock Stud 11 Spring 12a Medium 12b Seal Stamp 13 Printer Unit

Claims (1)

[Scope of utility model registration request] 1. A medium thickness detecting mechanism section for detecting the thickness of a medium passing between a print head and a platen provided facing the print head, and information from the medium thickness detecting mechanism section. An actuator that drives the platen so as to maintain the gap between the print head and the platen at an appropriate value, and a card holder attached to a position of the tip of the print head of a carriage that mounts the print head, A lock lever provided at a front end of a printer frame rotatably held by a first guide shaft that holds the carriage and is fixed to a frame, a lock stud that engages with the lock lever, and the lock stud of the platen. A platen gap adjusting device, comprising: a spring that biases the platen in a direction.