JP2011000764A - Printing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing apparatus which facilitates restoration even if a link lever for performing the pressure contact/isolation of a printing means comes off from a top cover.SOLUTION: The printing apparatus includes a casing body 2, the top cover 5, the printing means 32, a platen roller 35, a pressure contact/release mechanism that presses the printing means 32 into contact with the platen roller 35 and isolates from the platen roller 35, and the link lever 34 that has one end engaged with the top cover 5 and the other end connected with the pressure contact/release mechanism 51, and operates the pressure contact/release mechanism in conjunction with the opening and closing of the top cover 5 to perform the pressure contact/isolation of the printing means 32 to the platen roller 35. The top cover 5 has a guide rib 71 formed below a position where one end 34α of the link lever is engaged. When the one end 34α of the link lever comes off from the top cover 5 when the top cover 5 is opened, a guide surface 71A formed on the top surface of the guide rib 71 receives and holds the link lever 34.

Description

  The present invention relates to a printing apparatus having a casing main body on which a print medium wound in a roll shape is mounted, and an upper cover attached to the casing main body so as to be freely opened and closed.

2. Description of the Related Art Conventionally, various printing apparatuses have been proposed that have a casing main body on which a printing medium wound in a roll shape is mounted and an upper cover that is attached to the casing main body so as to be freely opened and closed.
For example, as in Patent Document 1, one end of a link lever that performs a pressure contact / separation operation of the thermal head to the platen roller is engaged with the upper cover of the printing apparatus, and the thermal head is moved in conjunction with closing the upper cover. There is a printing apparatus that automatically moves upward and presses a printing medium against a platen roller to enable printing. In this printing apparatus, when the upper cover is opened, the thermal head moves downward and moves away from the platen roller. Therefore, the user who wants to start printing inserts one end of the print medium between the two, If the cover is closed, the printer is ready for printing again.

JP 2009-028977 A

  However, in the printing apparatus of Patent Document 1 described above, one end of the link lever is detachably engaged with the upper cover. Therefore, when the user opens the upper cover and inserts the print medium between the platen roller and the thermal head, if the user touches the upper cover or the link lever, the link lever comes off the upper cover and falls downward. . In that case, there is a problem that the user must manually re-engage the link lever with the upper cover.

  Accordingly, the present invention has been made to solve the above-described problems, and provides a printing apparatus that can be easily restored even when a link lever that performs press-contact / separation operation of a printing unit is detached from an upper cover. For the purpose.

  In order to solve the above-mentioned object, a printing apparatus according to claim 1 includes a casing main body to which a printing medium wound in a roll shape is mounted, an upper cover that is attached to the casing main body so as to be openable and closable, and the casing. A printing unit disposed in the body main body for printing on a printing medium; a platen roller rotatably supported on the housing main body facing the printing unit; and the printing unit pressed against the platen roller. A press-contact / release mechanism that separates from the platen roller, and one end is engaged with the upper cover and the other end is connected to the press-contact / release mechanism. And a link lever that presses and separates the printing means from the platen roller. The upper cover is formed below a position where one end of the link lever engages. Comprising a guide rib, the guide surface formed on the guide rib top surface, said link lever end when said upper cover opened when deviating from above the cover, characterized in that it holds receiving the link lever.

  The printing apparatus according to claim 2 is the printing apparatus according to claim 1, wherein an opening angle of the upper cover from which the link lever is released is restricted, and the engagement is performed between the one end of the link lever and the upper cover. It is made by inserting the shaft portion formed in the other into the engagement hole formed in either one of the above, and when the one end of the link lever slides on the guide surface when closing the upper cover, The shaft portion is automatically inserted into the engagement hole.

  A printing device according to claim 3 is the printing device according to claim 2, wherein a chamfered portion is formed at one of the shaft portion, the engagement hole, or one end of the link lever. It is automatically inserted into the engagement hole through the chamfered portion.

  In the printing apparatus according to claim 1, the upper cover includes a guide rib formed below a position where one end of the link lever engages, and the guide surface formed on the upper surface of the guide rib has a link lever when the upper cover is opened. When the cover is removed from the upper cover, the link lever is received and held. For this reason, it becomes easy for the user to re-engage the link lever with the upper cover.

Further, in the printing apparatus according to claim 2, the opening angle of the upper cover is restricted even after the link lever is released. For this reason, the position of the guide rib does not change greatly after the link lever is detached from the upper cover, and the guide surface can more reliably receive and hold the link lever.
The link lever and the upper cover are engaged by inserting the shaft portion into the engagement hole. The link lever slides on the guide surface when the upper cover is closed, and the shaft portion is engaged with the engagement portion. Automatically inserted into the hole. Therefore, as long as the user closes the upper cover, the link lever released from the upper cover and held by the guide rib is automatically engaged.

  Furthermore, in the printing apparatus according to claim 3, a chamfered portion is formed at one of the shaft portion, the engagement hole, or one end of the link lever, and the shaft portion is engaged with the engagement via the chamfered portion. Automatically inserted into the hole. Therefore, the link lever reengagement when closing the upper cover is performed more smoothly.

It is a perspective view from the upper right side showing the printing apparatus of the present embodiment in a state in which the roll sheet holder is mounted and the link lever is detached from the upper cover and held on the guide surface of the guide rib with the upper cover opened. It is a rear view of the printing apparatus which concerns on this embodiment. It is a top view which shows the state which opened the upper cover of the printing apparatus which concerns on this embodiment. FIG. 4 is a cross-sectional view taken along the line AA ′ of the printing apparatus shown in FIG. FIG. 4 is a BB ′ side cross-sectional view of the printing apparatus shown in FIG. 3. It is a plane sectional view of a printing device in the state where an opened upper cover was cut. The enlarged portion shows the chamfered portion of the link lever and the upper cover.

  Hereinafter, a printing apparatus according to the present invention will be described in detail with reference to the drawings based on an embodiment of the present invention. In addition, the upper cover 5 in FIGS. 1 to 6 described below is in a state in which a link lever 34 described later is released and fully opened.

First, a schematic configuration of a printing apparatus to which a roll sheet holder according to the present embodiment is mounted will be described with reference to FIGS.
As shown in FIG. 1 and the like, a printing apparatus 1 includes a main body housing 2 made of resin, a roll sheet holder storage unit 4 that stores a roll sheet holder 3 around which a roll sheet 3A having a predetermined width is wound, and a roll sheet. The upper cover 5 is made of a transparent resin that covers the upper side of the holder housing 4. The upper cover 5 is attached to the rear upper edge of the main body housing 2 by a hinge so as to be opened and closed. Note that the rear edge of the upper cover 5 has claw portions 5C and 5C ′ (see FIG. 2) that are triangular in a side view. By contacting the upper end, the opening angle of the upper cover 5 is regulated. That is, when the claw portions 5C and 5C ′ come into contact with the rear upper end portion of the main body housing 2, the upper cover 5 is fully opened.
The roll sheet 3A includes a self-coloring long heat-sensitive sheet (so-called thermal paper) or a long label sheet in which a release paper is bonded to one side of the heat-sensitive sheet via an adhesive. Etc.

  The front cover 6 on the front side of the upper cover 5 is formed with a sheet discharge port 6A for discharging the printed roll sheet 3A to the outside. In addition, the power button 7A is pressed on the front surface on the upper side of the sheet discharge port 6A, and the cutter unit 8 (see FIG. 4) provided inside the sheet discharge port 6A is driven by pressing down to cut the roll sheet 3A. The cut button 7B and a feed button 7C for discharging the roll sheet 3A in the transport direction while being pressed are arranged substantially horizontally.

  Here, the cutter unit 8 has a fixed blade 8A and a movable blade 8B as shown in FIG. When the cut button 7B is pressed, the movable blade 8B is reciprocated in the vertical direction by a cutting motor composed of a DC motor or the like. Then, the roll sheet 3A cut by the fixed blade 8A and the movable blade 8B is discharged from the sheet discharge port 6A. The movable blade 8B is configured in a V shape when viewed from the front.

Further, as shown in FIG. 1, the tray member 9 is attached to the lower edge of the front cover 6 so as to be openable and closable so as to cover the front side of the front cover 6, and a finger is placed on the recess 9A formed at the upper end. It is configured so that it can be hung and rotated forward to open.
As shown in FIG. 2, an inlet 10 to which a power cord is connected is disposed on the back surface of the main body housing 2, and a USB (Universal Serial Bus) connected to a personal computer or the like is disposed on the side of the inlet 10. ) A connector 11 is provided.

  As shown in FIGS. 4 and 5, the upper cover 5 is formed in a substantially semicircular shape when viewed from the side. The left and right side edge portions with which the opening of the upper cover 5 of the main body housing 2 abuts are extended outward by a predetermined width (for example, about 10 mm) to form the respective step portions 13 and 13. .

  As shown in FIG. 3 and the like, elastic locking pieces 15, 15 formed on the inner side so as to be elastically deformable are provided on the left and right side wall portions on the front side of the roll sheet holder storage portion 4. Further, each elastic locking piece 15, 15 is formed with a locking projection 15 </ b> A having a triangular side section projecting outward, and each engaging recess 16 formed on the opening side edge of the upper cover 5. 16 is configured to be engageable.

  As a result, the upper cover 5 is rotated in the front direction and brought into contact with each step portion 13, whereby each elastic locking piece 15 and each engagement recess 16 are engaged, and the upper cover 5 is closed. Held in a state. Also, by engaging the recess 5A formed at the center of the front end of the upper cover 5 and turning it in the rear direction, the engagement between each elastic locking piece 15 and each engagement recess 16 is released, The upper cover 5 can be opened.

  Further, as shown in FIG. 1, a push claw portion 5 </ b> B projecting a predetermined length in the front direction is provided on the front left side of the recessed portion 5 </ b> A of the upper cover 5. When the upper cover 5 is closed, the position where the push claw portion 5B of the main body housing 2 abuts is configured by a micro switch or the like, and whether or not the push claw portion 5B is depressed, that is, the upper cover An upper cover detection switch 18 for determining whether or not 5 is closed is disposed.

  Further, as shown in FIG. 1, the printing apparatus 1 has a roll on one side edge portion (right side edge portion in FIG. 1) in a direction substantially perpendicular to the conveyance direction of the roll sheet holder storage portion 4. A holder support member 23 is provided in which a mounting member 21 having a substantially rectangular cross section that protrudes in the outer direction of the positioning holding member 20 constituting the sheet holder 3 can be fitted.

  As shown in FIG. 3 and the like, the mounting portion that extends substantially horizontally from the rear end edge portion of the insertion port 26 (see FIG. 4) into which the roll sheet 3A is inserted to the front upper end edge portion of the roll sheet holder storage portion 4. 29 is provided. Further, five second positioning groove portions 30A to 30E having a substantially L-shaped cross section corresponding to a plurality of width dimensions of the roll sheet 3A are formed at the edge corners on the rear side in the transport direction of the placement portion 29. Has been. Each of the second positioning groove portions 30 </ b> A to 30 </ b> E is formed so that the lower end portion of the tip contacting the mounting portion 29 of the guide member 28 (see FIG. 1) constituting the roll sheet holder 3 can be fitted from above. Yes.

  In addition, a positioning recess 4A having a horizontally long rectangular shape in a plan view from the inner base end of the holder support member 23 to the side face base end facing the roll support holder 23 is substantially perpendicular to the conveying direction. It is formed with a depth (in this embodiment, it is a depth of about 1.5 to 3 mm). The width direction of the positioning recess 4A is formed so as to be substantially equal to the width dimension of the lower end edge portions of the positioning holding member 20 (see FIG. 1) and the guide member 28 constituting the roll sheet holder 3.

  Further, at the inner base end portion of the holder support member 23 of the positioning recess 4A, a portion facing a sheet discriminating portion (not shown) extending from the lower end edge of the positioning holding member 20 in a substantially right-angle inner direction is a positioning recess. A discrimination recess 4B having a vertically long rectangular shape in plan view is formed in the transport direction so as to be deeper by a predetermined depth than 4A.

The discrimination recess 4B is composed of a push-type microswitch or the like, and has five sheet discrimination sensors P1, P2, P3, P4 for discriminating the type, material, roll sheet width, etc. of the roll sheet 3A. , P5 is provided in an L shape.
Each of the sheet discrimination sensors P1 to P5 is a known mechanical switch composed of a plunger, a micro switch, and the like, and the upper end of each plunger extends from the bottom of the discrimination recess 4B to the bottom of the positioning recess 4A. It is provided so that it may protrude to the part vicinity. Then, whether or not there is each sensor hole (not shown) formed in the sheet discriminating portion that extends in a substantially right-angle inner direction from the lower end edge portion of the positioning holding member 20 with respect to each of the sheet discriminating sensors P1 to P5. The type, material, roll sheet width, and the like of the roll sheet 3A mounted on the roll sheet holder 3 are detected by the on / off signal.

  In addition, a guide portion 31 is formed at the side end edge of the insertion port 26 on the holder support member 23 side to the rear end portion of the placement unit 29 substantially in the transport direction, and guides the roll sheet 3A to the insertion port 26. . Here, the inner end surface (the left end surface in FIG. 3) of the guide portion 31 is formed so as to be opposed to the inner end surface of the positioning member 20 fitted into the holder support member 23, that is, on the same plane. Has been. Thereby, the outer side edge portion of the roll sheet 3 </ b> A pulled out from the roll sheet holder 3 abuts on the inner end surface of the guide portion 31 and is guided to the insertion port 26.

  Further, as shown in FIG. 1 and the like, an engagement shaft 33 is erected on the inner side of the periphery of the opening of the upper cover 5 that faces the side edge of the holder housing 4 opposite to the holder support member 23. ing. The engaging shaft 33 is for attaching a resinous link lever 34 for moving a thermal head 32, which will be described later, to the upper cover 5 so as to be rotatable and detachable. That is, the engagement lever 33 </ b> A formed in the link lever edge 34 </ b> α on the upper cover side is fitted into the engagement shaft 33, whereby the link lever 34 is engaged with the upper cover 5. The upper cover 5 is provided with a guide rib 71 (having a width of about 5 mm in the present embodiment), which will be described later, below the link lever end edge portion 34α in a state of being engaged with the engagement shaft 33. Note that the engagement hole 34A in this embodiment is a through hole. The engaging shaft 33 is formed at a height substantially equal to the thickness of the link lever 34 (about 3 mm in this embodiment).

  As shown in FIG. 4, a platen roller 35 is rotatably supported on the inner side of the insertion opening 26 in the roll sheet conveyance direction. The thermal head 32 is fixed to the upper surface of a head support member 37 that is biased upward by a pressing spring 36. Further, the rear edge portion of the head support member 37 with respect to the transport direction is supported by the back surface portion of the frame 38 so as to be swingable in the vertical direction.

As shown in FIG. 5, the other end edge portion of the link lever 34 is inserted into an insertion hole 55 having a substantially vertically long cross section formed in the inner end edge portion of the step portion 13, and the release lever 51. It is connected with one end edge part of this so that rotation is possible.
The other edge of the release lever 51 is pivotally supported by a lever shaft 50 inserted into the engagement hole 51A of the left frame 47. The left frame 47 is pivotally supported at the left edge of the roller shaft of the platen roller 35. Further, the left end edge portion of the release shaft 48 having a partially cut surface is pivotally supported and protrudes outward by a predetermined length. A release gear 49 having a gear formed on an approximately half circumference portion of the outer peripheral surface is attached to the left end edge portion of the release shaft 48. A lever gear (not shown) that meshes with the release gear 49 is formed on the outer peripheral surface of the release lever 51 on the side of the engagement hole 51 </ b> A that faces the release gear 49 when the upper cover 5 is closed. Has been.
As shown in FIG. 4, the release shaft 48 is in contact with the tip of the lower interference member 57 on its lower surface. Although not explicitly shown, the lower interference member 57 is provided on the lower surface portion of the thermal head support member 37 and has a substantially L shape in side view.

  Therefore, when the link lever 34 is engaged with the upper cover 5 via the engagement shaft 33 and the engagement hole 34 </ b> A, when the upper cover 5 is closed, the link lever 34 is interlocked with the movement of the upper cover 5. Moving in the front direction, the release lever 51 is rotated counterclockwise in the left side view about the lever shaft 50. Then, the release gear 49 is rotated about 180 degrees in the clockwise direction in the left side view via a lever gear (not shown). As a result, the release shaft 48 is also rotated about 180 degrees in the clockwise direction in the left side view. Then, the tip of the lower interference member 57 is positioned below the notch surface of the release shaft 48. As a result, the tip of the lower interference member 57 is not pressed downward by the release shaft 48, so the head support member 37 is rotated upward by the pressing spring 36, and the thermal head 32 moves the roll sheet 3 </ b> A onto the platen roller 35. The printer is ready to print when pressed.

  On the other hand, when the link lever 34 is engaged with the upper cover 5 and the upper cover 5 is opened, the link lever 34 moves rearward, and a release lever 51, a lever gear (not shown), a release gear 49, a release shaft. Each 48 is rotated in the opposite direction. Then, the tip of the lower interference member 57 having a substantially L shape in side view is pushed downward on the cylindrical side surface of the release shaft 48, so that the head support member 37 is rotated downward against the urging force of the pressing spring 36. Thus, the thermal head 32 is separated from the platen roller 35. Then, the roll sheet 3 </ b> A is inserted through the insertion opening 26, and the roll sheet 3 </ b> A can be inserted between the platen roller 35 and the thermal head 32. Further, the lower edge portion of the release lever 51 comes into contact with the upper end of the outer periphery of the insertion hole 55, and the opening angle of the upper cover 5 is restricted. The opening angle restricted at this time is smaller than the opening angle restricted when the above-described upper cover claw portions 5C and 5C ′ abut against the rear upper end portion of the main body housing 2.

  In addition, as shown in FIG. 4, on the lower side of the roll sheet holder storage unit 4, a control for driving and controlling each mechanism unit such as the thermal head 32 by a command from an external personal computer or the like via a partition wall 39. A circuit board is formed, and a control board 40 to which the sheet discrimination sensors P1 to P5 are electrically connected is provided. A power supply board 41 on which a power supply circuit unit is formed is provided below the frame 38 via a partition wall 39.

  The thermal head 32 is connected to a connector 44 provided on the bottom surface side of the control board 40 by a flexible flat cable (FFC) 43. The control board 40 and the power supply board 41 are covered with a bottom cover 45 made of a thin steel plate (in this embodiment, made of steel plate such as SPCC having a thickness of about 0.5 mm) screwed to the bottom surface portion. ing.

  Next, a mechanism for re-engaging after the link lever is released from the upper cover will be described with reference to FIGS. 1, 4, 5, and 6. The link lever 34 engaged with the upper cover 5 is disengaged by bending the upper cover side link lever edge 34α inwardly (in the lower right direction in FIG. 1) more than the thickness of the link lever 34. End up. It can also be removed by pushing the opening of the upper cover 5 outward. The link lever 34 is detached from the upper cover 5 when the upper cover 5 is opened, that is, the lower edge portion of the release lever 51 connected to the link lever 34 engaged with the upper cover 5 abuts on the outer peripheral upper end portion of the insertion hole 55. It is easy to happen in the state that is. Even if the link lever 34 is detached from the upper cover 5 in this contact state due to the lightness of the link lever 34 to some extent or the friction between the release lever 51 and the lever shaft 50, the release lever 51 is counterclockwise as viewed from the left (see FIG. 5)).

  As described above, in the upper cover 5, the guide rib 71 is erected below the link lever end edge portion 34 α in a state where the upper cover 5 is engaged with the engagement shaft 33. For this reason, the link lever end edge portion 34α that is detached from the upper cover 5 is received by the guide surface 71A formed on the upper surface of the guide rib 71. Since the release lever 51 does not rotate as described above, the link lever 34 at this time rotates downward (in the lower left direction in FIG. 5) about the connecting portion with the release lever 51 as an axis.

  On the other hand, when the link lever 34 is released and the opening angle is not restricted, the upper cover 5 is further opened, and the claw portions 5C and 5C ′ of the upper cover 5 abut on the rear upper end portion of the main body housing 2 as described above. It will be in the state opened completely. In this state, as shown in FIG. 4, the guide surface 71A has a center C1 of the engagement shaft 33 viewed from the left side and a center of the engagement hole 34A in the link lever end edge portion 34α received on the guide surface 71A. C2 is formed so as to be on the same circle L around the rotation center T of the upper cover 5 (the upper cover is the axis of the main body hinge). Further, the line segment formed when the guide surface 71A is viewed from the side is formed so as to be a tangent to a circle centered on the rotation center T of the upper cover 5 (a circle indicated by M in FIG. 4).

  Further, as shown in FIG. 6, the engagement shaft 33 and the link lever end edge portion 34α are chamfered. This chamfer is formed along the circle L connecting C1 and C2 described above (see FIG. 4). As shown in the enlarged view of FIG. 6, the chamfered portion of the engagement shaft 33 and the chamfered portion of the link lever end edge portion 34α have the same chamfering angle. The chamfer is also formed in the engagement hole 34A. In the link lever end edge portion 34α, the circle formed by the outer side surface (the left side in FIG. 6) and the engagement hole 34A is larger than the circle formed by the inner side surface and the engagement hole 34A.

As shown in FIGS. 4 and 6, when the upper cover 5 is closed from the above state, the lower surface of the link lever end edge portion 34α received by the guide surface 71A is leftward as viewed from the left side (X in FIG. 4). The guide surface 71A slides in the direction). That is, the position of the guide rib 71 is moved by closing the upper cover 5 according to a positional relationship in which a line segment obtained by viewing the guide surface 71A from the side is a tangent to a circle centered on the rotation center T of the upper cover 5. The fluctuation of the position of the link lever 5 is slight. On the other hand, the engagement shaft 33 provided on the upper cover moves along the circle L in the X direction. Then, the engaging shaft 33 and the link lever end edge 34α come into contact with each other.
Here, as shown in FIG. 6, the chamfered portion of the engagement shaft 33 and the chamfered portion of the link lever end edge portion 34α are opposed to each other, and the engagement shaft 33 and the link lever 34α are connected to each chamfered portion. Will be in contact with each other. Therefore, the link lever end edge 34α rides on the engagement shaft 33 and slides further in the X direction. Even if the position of the link lever 5 is slightly changed when the upper cover 5 is closed, the engagement shaft 33 is easily inserted into the engagement hole 34A by chamfering the engagement hole 34A.

  Here, the thermal head 32 constitutes printing means. The roll sheet 3A constitutes a print medium. The release lever 51, the lever shaft 50, the release gear 49, the lower interference member 57, the release shaft 48, and the lever gear constitute a pressure contact / release mechanism. The engagement shaft 33 constitutes a shaft portion.

  Therefore, in the printing apparatus 1 according to the present embodiment, the upper cover 5 includes the guide rib 71 formed below the position where the link lever end edge portion 34α is engaged, and the guide surface 71A formed on the upper surface of the guide rib 71 is When the link lever end edge 34α is detached from the upper cover 5 when the upper cover 5 is opened, the link lever 34 is received and held. Therefore, the user can easily re-engage the link lever 34 with the upper cover 5 as before.

Further, in the printing apparatus 1 according to the present embodiment, the opening angle of the upper cover 5 is restricted even if the link lever 34 is released. For this reason, the position of the guide rib does not change greatly after the link lever is detached from the upper cover, and the guide surface can more reliably receive and hold the link lever.
The link lever 34 and the upper cover 5 are engaged by inserting an engagement shaft 33 formed on the upper cover into an engagement hole 34A formed on the link lever end edge 34α. 5 is closed, the link lever end edge portion 34α slides on the guide surface 71A, and the shaft portion is automatically inserted into the engagement hole. Therefore, as long as the user closes the upper cover 5, the link lever 34 that is detached from the upper cover 5 and held on the guide surface 71 </ b> A is automatically engaged.

  Further, in the printing apparatus 1 according to the present embodiment, chamfered portions are formed in the engagement shaft 33, the engagement hole 34A, or the link lever end edge portion 34α, and the engagement shaft 33 is engaged via these chamfered portions. It is automatically inserted into the joint hole 34A. Therefore, the reengagement of the link lever 34 when closing the upper cover 5 is performed more smoothly.

In addition, this invention is not limited to the said embodiment, Of course, various improvement and deformation | transformation are possible within the range which does not deviate from the summary of this invention. For example, although the engagement hole has penetrated in this embodiment, it does not need to penetrate if it can be engaged with the engagement shaft.
In the present embodiment, the position of the guide rib is such that a line segment obtained when the guide surface is viewed from the side when the upper cover is fully opened is on a tangent line of a circle centering on the rotation center of the upper cover. Thereby, since the fluctuation | variation of the link lever position at the time of closing an upper cover becomes small, a link lever is smoothly re-engaged with an upper cover. However, depending on the opening angle or the like of the upper cover that is regulated after the link lever is released, it does not necessarily have to be on the tangent line, and there is a slight angle between the tangent line and the line segment composed of the guide surface 71A. There may be a gap.
Further, unlike the present embodiment, there may be a case where an engagement hole is formed in the top cover and a shaft portion is formed in the link lever. In this case, the engagement hole needs to be chamfered and the shaft portion is preferably chamfered, but the link lever end edge does not need chamfering. On the other hand, even when the shaft portion is formed in the top cover and the engagement hole is formed in the link lever as in the present embodiment, depending on the opening restriction angle of the upper cover after the link lever is detached, the engagement hole Further, chamfering of the shaft portion is not always necessary.

DESCRIPTION OF SYMBOLS 1 Printing apparatus 2 Main body housing | casing 3 Roll sheet holder 3A Roll sheet 5 Upper cover 5C, 5C 'Nail | claw part provided in upper cover rear edge part 32 Thermal head 33 Engagement shaft 34 Link lever 34A Engagement hole 34 (alpha) Upper cover Side link lever edge 35 Platen roller 51 Release lever 71 Guide rib 71A Guide surface
T Rotation center of upper cover (hinge axis)
C1 Center of the engagement shaft viewed from the left side when the upper cover is fully opened C2 Centering on the center of the engagement hole LT viewed from the left side when the upper cover is fully opened and the link lever is held on the guide rib , A circle passing through C1 and C2, and a circle centered on MT and having a line segment formed by viewing the guide surface from the left side

Claims (3)

A housing body on which a print medium wound in a roll shape is mounted;
An upper cover attached to the housing body so as to be freely opened and closed;
Printing means disposed in the housing body for printing on a print medium;
A platen roller that is rotatably supported by the housing body facing the printing means;
A press-contacting / release mechanism that presses the printing unit against the platen roller and separates the printing unit from the platen roller;
One end is engaged with the upper cover and the other end is connected to the press contact / release mechanism, and the press contact / release mechanism is operated in conjunction with opening and closing of the upper cover to press and separate the printing means from the platen roller. In a printing apparatus having a link lever to perform,
The upper cover includes a guide rib formed below a position where one end of the link lever is engaged.
The guide surface formed on the upper surface of the guide rib receives and holds the link lever when one end of the link lever is detached from the upper cover when the upper cover is opened. The opening angle of the upper cover from which the link lever is released is restricted,
The engagement is performed by inserting a shaft portion formed in the other into an engagement hole formed in one of the link lever one end and the upper cover,
2. The printing apparatus according to claim 1, wherein the one end of the link lever slides on the guide surface when the upper cover is closed, and the shaft portion is automatically inserted into the engagement hole. . A chamfered portion is formed on one of the shaft portion, the engagement hole, or one end of the link lever,
The printing apparatus according to claim 2, wherein the shaft portion is automatically inserted into the engagement hole through the chamfered portion.

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