JP2002254716A - Mechanism for pressing down of tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism for pressing down of a tube, which can detect a fine tube by using even a general purpose photoelectric sensor and further does not cause a spark discharge from the pressing down mechanism to the printer. SOLUTION: A flag part 42 is set on a pressing strip 41 pressing a tube TU. When the tube is fed in, the flag part 42 moves upward together with the pressing strip 41 and it is detected that the tube TU is fed in by shielding of light to a photo acceptance part of the photoelectric sensor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube holding mechanism provided with a holding piece for holding a tube sequentially fed to a printing device for printing on the surface of the tube with a predetermined urging force from above to prevent the tube from floating.

[0002]

2. Description of the Related Art For example, at the time of electric work, a tube on which a connection terminal or the like is displayed may be attached to a cord to indicate to which terminal the cord is to be connected. A printing device is used for printing on the tube. The printing apparatus is provided with a thermal head, and predetermined characters and symbols are thermally transferred to the surface of the tube fed at a constant speed.

[0003] The tube is wound in a roll shape, and the end portion of the wound tube is pulled out and sequentially sent to a printing apparatus. In order to feed the tube at a constant speed, the tube is sandwiched between the pinch roller and the idle roller and sent to the thermal head.However, if the tube is sandwiched between the pinch roller and the idle roller while floating, the position of the tube with respect to the thermal head is Is shifted upward, and printing cannot be performed normally. Therefore, there is provided a tube holding mechanism for holding the fed tube from above to prevent the tube from floating.

The printing apparatus is provided with a photoelectric sensor, and when the tube is fed into the printing apparatus, it is detected by the photoelectric sensor that the tube has been fed. The photoelectric sensor includes a light emitting unit and a light receiving unit facing the light emitting unit. When light is received by the light receiving unit, the light receiving unit changes the electric signal according to the amount of received light and outputs the electric signal. When the tube is sent between the light emitting unit and the light receiving unit, the light emitted from the light emitting unit is blocked, and the electric signal output from the light receiving unit changes.

[0005]

The outer diameter of the tube fed into the printing apparatus differs depending on the type of the tube, and printing may be performed not only on a thick tube but also on a thin tube. Whatever the outer diameter of the tube is fed, it is necessary to use a photoelectric sensor having a large light receiving portion in order for the photoelectric sensor to detect the tube. However, general-purpose photoelectric sensors of a size that can be incorporated into a printing apparatus, and are widely sold, have a relatively small light receiving area and cannot detect a thin tube when fed.

Although it is technically possible to manufacture a photoelectric sensor in which the area of the light receiving portion is expanded without increasing the overall size of the photoelectric sensor, the photoelectric sensor can be manufactured more widely than a general-purpose type that is widely sold. The unit price increases.

By the way, in order to prevent the tube from being lifted by the pressing mechanism, it is necessary to bring the pressing mechanism into contact with the tube. When the tube is fed in a state where the pressing mechanism is in contact with the tube, friction occurs between the tube surface and the pressing mechanism, and static electricity is generated. Generally, the pressing mechanism presses the tube by forming the spring plate into a predetermined shape, but the spring plate is held by an insulator such as plastic. Then, the charge amount of the holding mechanism increases in proportion to the feeding amount of the tube. When the charge amount exceeds a certain amount, a spark discharge is generated from the pressing mechanism to the printing apparatus. When this spark discharge phenomenon occurs, it affects the control unit of the printing apparatus as noise, and the printing is disturbed or stopped, and in the worst case, the control unit may be damaged.

In view of the above problems, the present invention provides a tube holding mechanism that can detect a thin tube even by using a general-purpose photoelectric sensor and that does not cause spark discharge in the printing apparatus from the holding mechanism. The task is to

[0009]

According to a first aspect of the present invention, there is provided a tube holding mechanism for holding a tube sequentially fed to a printing device for printing on the surface of the tube from above with a predetermined urging force. In a tube holding mechanism provided with a holding piece for preventing the rising of the tube, a holding piece provided by the tube is provided in the printing device, and is provided in the printing device in the middle of the optical path of the photoelectric sensor which detects the presence of the tube by shielding the sent tube from light. Characterized in that a flag section for blocking the optical path in conjunction with the movement of the flag is provided.

[0010] Even if a photoelectric sensor having a small light receiving area that cannot directly detect a thin tube is used, even if a small tube is fed, the flag section blocks the optical path of the photoelectric sensor instead of the tube, and the tube is fed. Can be detected.

In order to solve the second problem, a tube holding mechanism according to the present invention holds a tube sequentially fed to a printing device for printing on the surface of the tube from above with a predetermined urging force to prevent the tube from rising. In a tube holding mechanism provided with a holding piece to be pressed, an antistatic portion in contact with a metal part of the printing device is formed continuously with the holding piece.

The static electricity is generated when the pressing piece comes into contact with the tube. However, since the antistatic portion is formed continuously with the pressing piece, the generated static electricity immediately flows from the antistatic portion to the metal part of the printing apparatus. An amount of static electricity enough to generate a spark discharge is not charged to the holding mechanism.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG.
This is a printing device provided with a thermal head for printing on the surface of U. The printing device 1 can also print on the surface of an ID strip or a heat-shrinkable tube inserted into a holder attached to a label or a cord having an adhesive layer on the back surface in addition to the tube TU. These prints are stored in cassettes (not shown), respectively,
Is set to When printing on a different type of print-receiving material, the entire cassette may be replaced.

The tube T to which the present invention is applied
U cannot be stored in a cassette because it is formed of, for example, vinyl chloride and is relatively thicker than the heat-shrinkable tube. For this reason, if the user purchases the product in the form of a roll and packed, the package is unwrapped and the rolled tube TU is released.
Must be pulled out and set on the printing apparatus 1 as it is.

Therefore, an adapter 2 for the tube is prepared so that the tube TU can be guided to the print head in a predetermined posture from the outside of the printer 1, and when printing on the tube TU, the adapter is used instead of the cassette. 2 is set in the printing device 1.

By the way, since the tube TU is not stored in the cassette as described above, the tube TU is likely to be covered with dust. In particular, synthetic resin, which is a raw material for tubes such as vinyl chloride, tends to be charged with static electricity, and thus has a problem of adsorbing dust.
Therefore, a tube cleaner 3 for removing dust adhered to the surface of the tube TU was attached to the adapter 2.

At least a photoelectric sensor 12 and a pinch roller 13 are attached to the cassette setting section 11. The photoelectric sensor 12 includes a light emitting unit and a light receiving unit that face each other. When the adapter 2 is set and the tube TU is fed, the tube TU is located between the light emitting unit and the light receiving unit. To block the light received from the light receiving unit. Further, the pinch roller 13 has a rotating shaft 13a.
, And the pinch roller 13 rotates at a constant feed speed when the rotating shaft 13a rotates. An idle roller 14 is provided near the pinch roller 13. When a cover (not shown) is closed, the idle roller 14 approaches the pinch roller 13 and
And the idle roller 14 so as to sandwich the tube TU.

Referring to FIG. 2, a holding member 4 is attached to adapter 2 as a holding mechanism for holding the tube TU from above with a predetermined urging force to stabilize the posture. The tube TU is inserted into the adapter 2 from the introduction section 21 and is sent out from the outlet 22 to the printing apparatus 1 while being held down by the holding metal 4.

Referring to FIG. 3, the holding member 4 is formed by stamping an elastic spring plate material. The holding member 4 has an arm-shaped holding piece 41 for holding the tube TU from above. A flag 42 extending downward is formed in the vicinity of the tip of the holding piece 41. The holding piece 4 has a contact piece 4 serving as an antistatic portion.
4 is formed, and the adapter 2 is connected to the cassette setting section 1
When set to 1, the contact piece 44 comes into contact with the tip of the rotating shaft 13a.

Referring to FIG. 4, a transmission window 43 is opened in the flag section 42. Reference numeral 12a denotes a light receiving unit of the photoelectric sensor 12, and the flag unit 42 is located between the light emitting unit and the light receiving unit of the photoelectric sensor 12. When the tube TU is not set on the adapter 2, the holding piece 41 is lowered to the lowermost position. As shown by a solid line in FIG. 4, light emitted from the light emitting unit passes through the transmission window 43 to the light receiving unit. Received. Therefore, most of the light from the light emitting unit is received by the light receiving unit, and the photoelectric sensor 12 does not detect the tube TU.

Next, when a tube TU, which is located below the light receiving portion 12a and is too thin to block light from the light emitting portion, is fed into the adapter 2, the holding piece 41 is pushed up by the tube TU, and the flag portion 42 is raised upward. Moving. Then, the light passing through the range 43a indicated by oblique lines in FIG. 4 is blocked by the flag unit 42, and the amount of light received by the light receiving unit 12a decreases. Therefore, the photoelectric sensor 12 can detect that the tube TU has been sent.

When the tube TU is continuously fed at a constant speed, the holding piece 41 and the tube TU continue to rub against each other, so that static electricity is generated at the contact portion and the holding metal 4 is charged. Since the main body of the adapter 2 is formed of plastic, static electricity charged on the holding member 4 cannot escape to the main body of the adapter 2. Therefore, as shown in FIG. 5, the contact piece 44 is made to contact the rotating shaft 13a. With this configuration, the static electricity charged on the holding member 4 immediately escapes from the contact piece 44 to the rotating shaft 13a,
High-voltage static electricity is not charged so that spark discharge occurs. The rotating shaft 13a is rotatably held by a metal chassis inside the printing apparatus 1.

[0023]

As is apparent from the above description, the present invention can detect a thin tube even if a general-purpose photoelectric sensor having a relatively small light receiving area is used, because the holding section is provided with the flag section. it can.

In addition, since the antistatic portion is provided, even if the holding piece is charged with static electricity, the static electricity can be released immediately and the occurrence of spark discharge between the printing apparatus and the holding mechanism can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing details of an adapter.

FIG. 3 is a view showing the shape of a holding metal fitting.

FIG. 4 is a diagram showing a relationship between a flag unit and a light receiving unit;

FIG. 5 is a view showing the operation of a contact piece.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer 2 Adapter 3 Tube cleaner 3 4 Holder 41 Presser piece 42 Flag part 44 Contact piece TU tube

Continued on the front page (72) Inventor Takuma Washizuka 1234 Machi, Iwai-shi, Ibaraki Japan Typewriter Co., Ltd. Iwai factory F-term (reference) 2C055 CC00 CC01 2C062 RA01

Claims (2)

[Claims] 1. A tube holding mechanism provided with a holding piece for holding a tube sequentially fed to a printing device for printing on the surface of the tube with a predetermined urging force from above to prevent the tube from floating, provided in the printing device.
A tube retainer characterized by providing a flag portion in the optical path of the photoelectric sensor that detects the presence of the tube by shielding the supplied tube from light and interlocking with the movement of the holding piece due to the feeding of the tube. mechanism. 2. A tube holding mechanism having a holding piece for holding a tube sequentially fed to a printing device for printing on the surface of the tube with a predetermined urging force from above to prevent the tube from floating, wherein a metal portion of the printing device is provided. A tube holding mechanism, wherein an antistatic portion to be contacted is formed continuously on the holding piece.