KR19990014280A - Printer device - Google Patents

Abstract

The printer device of the present invention improves operability and reduces the number of parts when performing maintenance such as paper jam or head cleaning. The printer device has a pressurizing cam which rotates in interaction with the opening and closing of the lid member, and releases the head block without increasing pressure by the leaf spring as an elastic member, thereby increasing the amount of opening. Create a printer frame. Therefore, operability can be improved when assembling and during maintenance such as paper jam or head cleaning. Further, the third cam surface of the pressure cam moves the moving piece of the detection switch by the operation of opening the cover member. Thus, the operation of opening and closing the lid member and the operation of the head block contacting and non-contacting with the platen roller with only one switch can be detected, thereby reducing the number of parts.

Description

Printer device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal printer for forming an image on a thermally sensitive recording paper using a thermal head, and more particularly to a thermal printer with improved operability such as paper jams or head cleaning.

The thermal printer is configured to form a desired image on recording paper using a thermal head.

In this type of small thermal printer, the thermal head is rotatably moved in contact with the platen roller through the pressing force of the pressing member such as a leaf spring of a certain type. When setting the heat-sensitive recording paper or when a jam occurs, after opening the cover member, the release lever installed therein is rotated so that the pressing force such as the leaf spring is released directly or indirectly. In this way, the heat head can be separated from the platen roller.

With such a structure, for example, there is a need to operate the release lever after opening the cover member during maintenance. Therefore, the housing of the opening must have a space for performing maintenance as well as a space for operating the release lever. Therefore, the size of the device tends to be large because the space as described above must be secured. In addition, the structure is complicated because two detection switches must be provided for separately detecting the state of the release level and the state of the lid member.

Moreover, when such a small-line thermal printer has a structure requiring a release lever, the release lever has a rotation support shaft disposed near the paper outlet of the housing, and is installed at a position away from the rotation support shaft of the thermal head. . As a result, the number of parts is increased because there must be a mechanism for transmitting the action force of the release lever.

On the other hand, for example, there is a thermal printer disclosed in Japanese Patent Application Laid-open No. H7-309052, which causes the thermal head to be separated from the platen roller by the interaction with opening and closing the lid member without the need for the release operation with the release lever. It is structured to be able.

The device has a cam member that rotates in interaction with opening and closing the lid member. In the open position of the lid member, the thermal head is pressed against the pressing force of the leaf spring by the cam member so that the thermal head is moved away from the platen roller.

However, in this structure, the pressing force of the leaf springs acts until the heat head is completely removed from the platen roller. Large opening force is required when opening the cover member. Therefore, it is difficult to make space for head cleaning even though the space for inserting paper or removing paper jam can be separated.

As described above, the apparatus requiring the release lever mentioned above requires two detection switches to detect the release lever state and the lid member state, and further, a mechanism for transmitting the action force of the release lever. Therefore, there is a problem of increasing the number of parts. Moreover, since the action force by the release lever is increased, there is a need to increase the space for operating the release lever. This increases the size of the device and requires a mechanism for transmitting the action force of the release lever, thus increasing the number of parts.

Further, in the device having a structure in which the heat head is separated from the platen roller by interaction with opening and closing the lid member, the compressive force of the elastic member increases as the heat head moves away from the platen roller. Therefore, there is a considerable difficulty when opening the cover member.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and an object thereof is to provide a line thermal printer which can improve operability when performing maintenance such as paper jam or head cleaning, and to reduce the number of parts in order to achieve a size reduction. will be.

The line thermal printer according to the present invention includes a housing having an opening, a platen roller rotatably disposed in the housing, a head block disposed in contact with and in contact with the platen roller, and a head in contact with and in contact with the platen roller. A head unit supporting plate for supporting the block, an elastic member for pressing the head block in the direction pressed against the platen roller, a cover member disposed on the housing for opening and closing the opening and closing the opening and closing the cover member In interaction with the operation, the head block is pressed against the platen roller by the pressing force of the elastic member when the lid member is in the closed position, and the elastic member when the lid member is in the open position. Release the pressing force and press the predetermined position of the head unit support plate so that the head unit From includes a pressing cam arranged to move apart.

In this invention, the pressurizing cam which rotates in interaction with the opening and closing of the lid member causes the head block to be pressed against the platen roller through the pressing force of the elastic member when the lid member is in the closed position. When the lid member is in the open position, the pressing force of the elastic member is released, and the head unit support plate is pressed in its predetermined position so that the head block is not in contact with the platen roller.

Moreover, the printer frame is detachably attached to the opening of the housing, the platen roller is rotatably supported, and the head unit support plate is rotatably supported to support the head block and the elastic member. The lid member is rotatably supported, and the lid member has a pressure cam mounted on the rotating shaft of the lid member to release the pressing force of the elastic member when the lid member is in the open position.

In this invention, the printer frame is made as a unit including main parts such as a head unit support plate, a lid member, and a pressure cam for supporting the platen roller, the head block and the elastic member therein. Therefore, it is easy to assemble the main parts to the housing. It is easy to change parts during maintenance because the main part can be exposed to the outside by taking the unit part from the housing. Incidentally, it is possible to perform cleaning only by opening the lid.

Moreover, the pressure cam has a first cam surface for pressing a predetermined position of the head unit support plate when the cover member is in an open position, and a second cam surface for pressing the elastic member when the cover member is in a closed position. Equipped with.

In the present invention, when the pressing cam is rotated by mutually opening and closing the lid member when the lid member is in the open position, the first cam surface of the pressing cam presses a predetermined portion of the head unit support plate, whereby the head block is It is moved away from the platen roller gradually. At this time, the second surface of the pressure cam is in a non-contact state with the elastic member. Therefore, the pressing force by the second cam surface is released to smoothly perform the release operation of the head block.

Further, the pressurizing cam has a pressing force receiving surface for receiving the pressing force of the elastic member board when the pressing cam is in a position just before completing the opening of the lid member.

In this invention, when the press member is rotated in interaction with opening and closing the cover member when the lid member is in the position just before fully opened, the second cam surface of the pressurized cam is placed in a non-contacted position with the elastic member. After the force for pressing the elastic member by the second cam surface is released, the elastic member is brought into contact with the pressing force receiving surface, and the force of opening the lid member is added to the pressing force, thereby holding the open position of the lid member.

Moreover, the pressurizing cam has a third cam surface for pressing the moving piece of the detection switch disposed in the housing when the lid member is in the closed position.

In the present invention, since the third cam surface of the pressure cam moves the moving piece of the detection switch by opening the cover member, only the detection switch of one terminal opens and closes the cover member, and the head block contacts the platen roller. Non-contacting motion can be detected.

1 is a view from behind of the printer unit of the line thermal printer of the present invention;

2 is a cross-sectional view taken along line A-A of the printer unit of FIG.

3 is a cross-sectional view showing an open state of the cover member of FIG.

4 is a cross-sectional view taken along line B-B of the printer unit of FIG.

5 is a cross-sectional view showing a state in which the cover member of FIG. 4 is open.

* Explanation of symbols for main parts of the drawings

10 housing 12 opening

13 insertion hole 14 guide part

15: guide passage 21: detection switch

22: moving sheet 30: printing paper

100: printer unit 110: printer frame

120: sleeve 130: cover member

131: arm 132: outlet

140: support shaft 141-143: pressure cam

144: first cam surface 145: second cam surface

146: leaf spring receiving surface 147: third cam surface

150: head block support shaft 160, 161: head unit support arm

163: head unit support plate 164-167: groove

170: leaf spring 171-174: pressure piece

180: head block 181: ceramic substrate

183 screw 190 support shaft

193: platen roller 194: platen drive gear

Referring to the drawings, embodiments of the present invention will be described below.

1 to 5 show one embodiment of the thermal printer of the present invention, and FIG. 1 shows a printer unit detachably housed in a housing to be mentioned below.

In these figures, the housing 10 has an opening 12 formed on the upper side of the front 11, for example as shown in Figs. Through this opening 12, the printer unit 100 shown in FIG. 1 can be detachably accommodated.

The printer unit 100 has a printer frame 110 that is generally rectangular in U-shape, as shown in FIG. The printer frame 110 has a sleeve 120 rotatably attached to its side frames 111 and 112. The sleeve 120 is integrally formed with the cover member 130 and the arm 131 so that the cover member 130 is opened and closed by the sleeve 120.

In addition, the sleeve 120 has an axial bore (not shown) that fits one end of the support shaft 140 having a rectangular cross section. Three pressure cams 141-143 are disposed on the support shaft 140. These pressurizing cams 141-143 push the first cam surface 144, the leaf spring 170 hereinafter referred to, to push out the bent portions 162 of the head unit support arms 160, 161 hereinafter referred to. To release the second cam surface 145 and the leaf spring receiving surface 146 subjected to a biasing force by the pressing pieces 171-174 of the leaf spring when releasing the pushing force of the leaf spring 170 to be mentioned below. Equipped.

However, the pressurizing cam 141 is provided with the 3rd cam surface 147 for pressurizing the moving piece 22 of the detection switch 21 mounted in things, such as the interface board 20 etc., for example. By turning on / off the detection switch 21, the opening / closing state of the lid member 130 and the release state of the head block 180 to be described below are detected.

In addition, an end portion of each of the headblock support shafts 150 is disposed to be rotatable on the side plates 111 and 112 of the printer frame 110 under the sleeve 120. Each end of the headblock support shaft 150 has head unit support arms 160, 161. The head unit support arms 160 and 161 have curved section portions 162 bent inwardly to each other on their upper end sides, respectively.

When the first cam surface 144 of the pressing cams 141 and 143 is pressed against the curved piece 162, the head block 180 is released by pressing as described below.

Each head unit support arm 160, 161 has a head unit support plate 163 formed integrally therewith. Grooves 164-167 are formed in the head unit support plate 163 to allow the leaf springs 170 to extend from the pressure pieces 171-174 toward the pressure cams 141-143 as will be discussed below.

The head unit support plate 163 has an aluminum head block 180 attached to it with a plurality of screws 22 on the surface side and an overall rectangular U-shaped leaf spring 170. The leaf spring 170 is provided with the pressing pieces 171-174 folded back upwards. These pressing pieces 171-174 extend rearward of the head unit supporting plate 163 to face the pressure cams 141-143 through the grooves 164-167 of the head unit supporting plate 163.

On the surface side thereof, a ceramic substrate 181 having a heat generating element (print head) is fixed to the head block 180. The ceramic substrate 181 is provided with a sealing part 182 at the lower part in order to seal the driver etc. which consist of IC. The head block 180 is provided with a protective cover 184 at the bottom of the head block 180 to protect the sealing portion 182 fixed by the screw 183.

In addition, the side plates 111 and 112 of the printer frame 110 support them so that both ends 191 and 192 of the support shaft 190 can be rotated at a position slightly lower than the attachment position of the sleeve 120. The platen roller 193 is attached to the support shaft 190. The platen drive gear 194 is provided on one end side 191 of the support shaft 190. When the platen drive gear 194 is disposed and housed in the housing 10 of the printer unit 100, the platen drive gear 194 is engaged with the drive gear of the omitted driving mechanism provided inside the housing 10.

The housing 10 has an insertion hole 13 in the front 11 on its lower side. The insertion hole 13 is formed in a horn shape in cross section so that the print paper 30 can be easily inserted at this end. The insertion hole 13 has a guide portion 14 formed with a smoothly curved surface upward so that the print paper 30 inserted therein can be guided upward.

The insertion hole 13 has a guide passage 15 extending upwardly up to the junction between the head block 180 and the platen roller 193 in the inner portion thereof. The guide passage 15 is provided with a guide sheet 16 extending in the inner part to the vicinity of the place where the head block 180 and the platen roller 193 are connected to each other.

Here, although not shown, a sheet detection sensor is provided in the guide passage 15. When detecting the print paper 30 inserted through the insertion hole 13, the aforementioned drive mechanism (not shown) is driven to rotate the platen roller 193.

At the end, the platen roller 193 rotates when the print paper 30 is forcibly drawn along the guide passage 15 and the guide plate 16 to the junction between the head block 180 and the platen roller 193. As a result, the printing paper 30 is wound around the peripheral surface of the platen roller 193.

The outlet 132 is provided in the cover member 130 at a position corresponding to the platen roller 193 for ejecting the print paper 30 after it is printed. In addition, the outlet 132 has a guide portion 133 that is curved toward the front 11 of the housing 10. The printed print paper 30 is discharged to the outside through the discharge port 132 at the end while being guided by the guide portion 133.

When printing the printing paper 30, the power supply (not shown) on the housing 10 side is first turned on, and then the printing paper 30 opens the insertion hole 13 at the front 11 side of the housing 10. Is inserted at the end through. At this time, the end of the printing paper 30 is inserted into the cross section of the insertion hole 13 can be easily inserted. At the end, the print paper 30 is guided toward the upper guide passage 15 by the guide portion 14 which is gently curved upward.

At this time, the platen roller 193 is rotated by detecting the insertion of the print paper 30 with the paper detection sensor not shown provided in the guide passage 15 and driving the drive mechanism not shown in the housing 10.

When the end of the printing paper 30 is inserted along the guide plate 16 to the junction of the head block 180 and the platen roller 193, the printing paper 30 is rotated by the platen roller 193. It is printed by an unillustrated heating element (print head) of the head block 180 while being wound on the outer circumferential surface of the platen roller 193.

In the printing operation (line row type) by a heating element (print head) (not shown), the end of the printing paper 30 is directed to the outlet 132 side of the cover member 130 by the rotation of the platen roller 193. Is forced out. At this time, the end of the print paper 30 is supplied toward the outlet 132 side while being guided by the guide portion 133 that is curved toward the front 11 side of the housing 10, and is discharged from the outlet 132. .

When the printing on the printing paper 30 is finished and the rear end of the printing paper 30 is released from the platen roller 193, the driving of the driving mechanism (not shown) in the housing 10 is stopped and the platen roller is stopped. Rotation of 193 is stopped.

On the other hand, for example, when a paper jam occurs during a print operation, the paper jam can be avoided by the following process.

That is, the cover member 130 is rotated in the arrow direction (counterclockwise) in the state shown in Figs. 3 and 5 in the state shown in Figs. At this time, the sleeve 120 shown in Figure 1 is rotated with the rotation of the arm 131 of the cover member 130 in the same direction, whereby the support shaft 140 attached to the sleeve 120 in the same direction Is rotated. This causes the three pressure cams 141-143 attached to the support shaft 140 to rotate counterclockwise.

When these pressure cams 141-143 rotate, the pressure cam 141 is first separated from the moving piece 22 of the detection switch 21 on the third surface 147. By removing the force for pressing the moving piece 22, it is detected that the lid member 130 is opened and that the head block 180 is released.

At this time, the pressure cam (141-143) for pressing each pressing piece (171-174) of the leaf spring 170 gradually moves away from these pressing pieces (171-174) on their second surface (145). Thus, the force applied to the pressing pieces 171-174 is released.

Also, at this time, the pressing cams 141 and 143 provided at the respective ends of the support shaft 140 lower the curved portion 162 from the upper side of the head unit support arms 160 and 161 on their first cam surfaces 144. Press Due to this pressing force, the head unit support arms 160 and 161 are rotated counterclockwise with respect to the head block support shaft 150, so that the head block 180 mounted on the surface side of the head unit support plate 163 is mounted. ) Is gradually moved away from the platen roller 193.

At this time, the second surface 145 of the pressure cam (141-143) for pressing the pressing piece (171-174) of the leaf spring 170 is moved away from the pressing piece (171-174) as described above. Thus, the pressing force of each pressing piece (171-174) is released. Therefore, the force which presses the curved part 162 of the 1st cam surface 144 of the pressurizing cams 141 and 143 is reduced. As a result, the head block 180 is smoothly released due to the rotation of the head unit support plate 163.

When the cover member 130 is opened just before the open position as shown in Figs. 3 and 5, the pressing pieces 171-174 have the ends of the leaf spring receiving surfaces of the pressing cams 141-143. It moves toward 146 side, and presses these leaf spring receiving surfaces 146. The force that the pressing pieces 171-174 push the leaf spring receiving surface 146 acts in the direction of opening the cover member 130 (counterclockwise direction). Therefore, the cover member 130 is pushed by the pushing force at the position just before the cover member 130 is opened, so that the cover member 130 is in the open position.

In this way, when the cover member 130 is opened, the opening 12 of the housing 10 is opened. Thus, for example, the print paper jammed between the head block 180 and the platen roller 198 can be easily taken out.

In addition, since the heat head 181 is exposed from the opening 12 of the housing 10 as described above, maintenance such as head cleaning can be easily performed.

In this way, in the present embodiment, the pressure cams 141-143 rotate in interaction with the opening and closing operation of the cover member 130. As a result, when the cover member 130 is in the closed position, the pressing force of the leaf spring 170 as the elastic member acts so that the head block 180 is pressed into contact with the platen roller 170 side. When the cover member 130 is in the open position, the leaf spring 170 is released from its pushing force so that the head unit support plate 163 is pushed to a predetermined position, and thus the head block 180 is platen roller 193. Is moved away from Therefore, the operation of opening the cover member 130 and releasing the head block 18 is desired.

In addition, in the present embodiment, the printer frame 110 is the head unit support plate 163, cover member 130, and cover for supporting the platen roller 193, the head block 180 and the leaf spring 170 Interaction with the opening operation of the member 130 is made as a unit incorporating major components such as pressure cams 141-143 that make the headblock 180 contact and non-contact with the platen roller 193. Therefore, the assembly to the housing 10 becomes easy. In addition, since the main parts can be exposed to the outside by taking the unit part from the housing 10, maintenance such as replacement of parts can be easily performed.

Furthermore, in this embodiment, when the pressurizing cams 141-143 are rotated by interacting with opening and closing the cover member 130 when the cover member 130 is in the open position, the pressurizing cams 141-143 are rotated. The first cam surface 144 of the press the respective curved piece portion 162 disposed at a predetermined position of the head unit support plate 163. This causes the head unit support plate 163 to be rotated so that the head block 180 is moved away from the platen roller 163. At this time, the second cam surface 145 of the pressure cams 141-143 moves away from the leaf spring 170. Therefore, the force that the second cam surface 145 presses the leaf spring 170 is released, and the force that the first cam surface 144 presses against the curved portion 162 is reduced, thereby improving operability.

Furthermore, in this embodiment, when the cover member 130 is in the position just before fully opened, the second cam surface 145 of the pressure cams 141-143 is separated from the leaf spring 170 so that the leaf spring 170 To release the pressing force. Thereafter, the pressing pieces 171-174 of the leaf spring 170 provide a pressing force to the leaf spring receiving surface 146, which is the leaf spring pressing surface 146, which is the pressing receiving surface for the pressing cams 141-143. Therefore, the pressing force is added to the opening force of the cover member 13, so that the cover member 130 maintains the open position, so that no locking mechanism is required.

In addition, in the present embodiment, the moving piece 22 of the detection switch 21 can move through the third cam surface 147 by the opening operation of the cover member 130. Therefore, the opening and closing of the lid member 130 can be detected only by one detection switch 21, and the contact and non-contact operations between the head block and the platen roller can be detected. Therefore, the number of parts can be reduced.

As described above, according to the line thermal printer of the present invention, the pressure cam rotating in the interaction with opening and closing the lid member releases the head block without being pressed by the elastic member, thereby increasing the opening amount. . Therefore, it is possible to improve operability when performing maintenance such as paper jam or head cleaning.

Further, the third cam surface of the pressure cam moves the moving piece of the detection switch by the operation of opening the cover member. Therefore, only one switch can detect the opening and closing operation of the lid member and the operation in which the head block is in contact with and not in contact with the platen roller, and the number of parts can be reduced.

Claims (5)

In the printer device, A housing having an opening, A platen roller rotatably disposed in the housing, A head block having a print portion and disposed in contact with and non-contact with the platen roller, Head unit support plate for supporting the head block, An elastic member for pressing the head block in a direction in which the platen roller is pressed against and in contact with the platen roller; A lid member disposed on the housing for opening and closing to open and close the opening; In interaction with the opening and closing of the lid member, the head block is pressed against the platen roller by the pressing force of the elastic member when the lid member is in the closed position, and the lid member is opened. A pressurizing cam arranged to release the pressing force of the elastic member and to press a predetermined position of the head unit support plate to move the head unit away from the platen roller when in the Printer apparatus comprising a. According to claim 1, Removably attached to the opening of the housing and the platen roller is rotatably supported, the head unit support plate is rotatably supported to support the head block and the elastic member, Furthermore, the cover member further comprises a printer frame rotatably supported, wherein the cover member is pressurized on the rotating shaft of the cover member to release the pressing force of the elastic member when the cover member is in the open position. A printer device having a cam. 3. The pressure cam according to claim 2, wherein the pressure cam has a first cam surface for pressing a predetermined position of the head unit support plate when the cover member is in an open position, and presses the elastic member when the cover member is in a closed position. A printer device comprising a second cam surface for. The printer apparatus as claimed in claim 1, wherein the pressure cam has a pressing force receiving surface for receiving the pressing force of the elastic member board when the lid member is in the position just before the lid member is completely opened. The printer apparatus according to claim 1, wherein the pressure cam has a third cam surface for pressing the moving piece of the detection switch disposed in the housing when the cover member is in the closed position.