JP4950261B2 - Platen roller support structure and printer - Google Patents

Description

The present invention relates to a platen roller support structure and printer.

  2. Description of the Related Art Conventionally, there is a printer that conveys a sheet between a platen roller and a print head biased toward the platen roller, and prints on the sheet supported by the platen roller with the print head. As such a printer, a pair of shaft portions are provided at both end portions of the platen roller, a bearing member is provided in each of the pair of shaft portions, and the bearing members are spaced apart from each other and are arranged to face each other. What is supported by a support frame is known.

  In such a printer, if the platen roller is worn due to friction between the platen roller and the paper, the print quality is deteriorated. Therefore, it is desirable to be able to replace the platen roller.

  Therefore, a bearing member provided at one end of the platen roller is supported by a bearing hole provided in one of the pair of support frames, and a bearing member provided at the other end of the platen roller is provided in a U-shaped groove provided in the other support frame. Further, there is one in which a bearing member on the other end side of the platen roller is supported on a support frame by a platen roller holding member (for example, see Patent Document 1). The platen roller holding member is screwed to the support frame. In this printer, the platen roller holding member is released from the support frame, so that the platen roller can be removed from the pair of support plates and replaced.

  However, in the conventional printer, in order to remove the shaft portion on one end side of the platen roller from the bearing hole supporting the bearing member on one end side of the platen roller, the screw is removed and the platen roller holding member is removed from the support frame. After removing the platen roller, the shaft part is slanted and pulled out to the side. After that, the platen roller must be removed from between the pair of support plates, which takes time to remove the platen roller. There's a problem.

  SUMMARY An advantage of some aspects of the invention is that a platen roller can be removed from a pair of support frames relatively easily.

In order to solve the above-described problems and achieve the object, a platen roller support structure of the present invention includes a platen roller that supports a recording medium, a pair of shaft portions provided at both ends of the platen roller, and the pair of pairs. A pair of E-rings provided at the tip of the shaft portion, a groove at least partially located between the platen roller and the E-ring in the shaft portion, and a larger diameter portion than the larger diameter portion A small-diameter portion having a small outer diameter located on the platen roller side of the large-diameter portion and a through-hole penetrating the large-diameter portion and the small-diameter portion are provided, and the shaft portion is inserted into the through-hole, and at least one of them a pair of bearings but is capable of movement relative to the shaft portion along the axial direction of the platen roller between said platen roller and said E ring, for rotatably supporting the platen roller through the shaft portion And wood, the shaft portion is capable of passing through and the bearing member is the shaft portion in communication with the opening and the opening shape is not pass can enter and exit through the opening and the small diameter portion A pair of support frames which are formed to be detachable fitting holes and are arranged opposite to each other, and attachable to and detachable from the groove in a direction perpendicular to the axial direction of the platen roller ; A positioning member that contacts the bearing member in a state of being attached to the groove between the E-ring and that positions the platen roller and the bearing member in the opposing direction of the pair of support frames. , the small diameter section is characterized Hamada' capable der Rukoto into the fitting hole in the opposing direction of the pair of supporting frames.

  The printer of the present invention includes the platen roller support structure and a print head for printing on a recording medium supported by the platen roller.

  According to the present invention, it is possible to remove the platen roller from the pair of support frames relatively easily.

FIG. 1 is a diagram showing a basic configuration of a printer according to an embodiment of the present invention. FIG. 2 is a perspective view showing the printer with the upper unit opened. FIG. 3 is a perspective view showing the printer with the cover removed and the upper unit opened. FIG. 4 is a plan view showing the platen roller support structure and its surroundings. FIG. 5 is an exploded perspective view showing the platen roller support structure. FIG. 6 is a side view showing a part of the support frame. FIG. 7 is a plan view showing a platen roller support structure. FIG. 8 is a plan view showing the platen roller unit. FIG. 9 is a plan view showing a part of the platen roller unit. FIG. 10 is a perspective view showing a positioning member. FIG. 11 is a side view showing the positioning member and tool in a state where the shaft portion of the platen roller unit is sandwiched. FIG. 12 is a side view showing the tool in a state where the positioning member is sandwiched. FIG. 13 is an explanatory diagram for explaining a procedure for engaging the tool with the positioning member. FIG. 14 is an explanatory diagram for explaining a process of removing the platen roller.

  Exemplary embodiments of a platen roller support structure, a printer, and a tool according to the present invention will be explained below in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram showing a basic configuration of a printer P according to the present embodiment, FIG. 2 is a perspective view showing a printer with an upper unit opened, and FIG. It is a perspective view which shows the printer of the open state. First, the basic configuration and basic operation of the printer P will be described with reference to FIGS. 1 to 3.

  The printer P includes a printer main body 1 to which various parts are attached, and an upper unit 2 is attached to the printer main body 1 so as to be freely opened and closed. As shown in the figure, the printer P is formed with a guide path 5 for pulling out the roll paper 3 as a recording medium and leading it to a paper discharge port 4 provided in front of the printer P. A roll paper storage holder 6 for storing and holding the roll paper 3 is provided in the printer main body 1 along the guide path 5, and the roll paper 3 is drawn out from the roll paper storage holder 6 to be printed. A print transport unit 7 and a paper cutting unit 8 for cutting the roll paper 3 are provided.

  The roll paper storage holder 6 is provided with a hopper 9 for storing the roll paper 3 and support rollers 10 and 11 for rotatably supporting the stored roll paper 3. The support rollers 10 and 11 are formed on the bottom surface 9 a of the hopper 9 with a predetermined interval and are formed in the recesses of the grooves 12 and 13 having a semicircular arc cross-sectional shape. The roll paper 3 is rotatably supported around an axis oriented in the same direction as the axial direction. The print transport unit 7 includes a thermal head 14 that is a print head for printing on the roll paper 3 drawn from the hopper 9 and a platen roller 15. As shown in FIG. 1, the thermal head 14 is disposed so as to be brought into contact with the platen roller 15 through the guide path 5 with a predetermined pressure. The thermal head 14 includes a plurality of heat generating elements (not shown), and the plurality of heat generating elements are selectively energized to generate heat and come into contact with the roll paper 3 which is thermal paper. The platen roller 15 supports the roll paper 3 and also has a function for pulling out and transporting the roll paper 3. The platen roller 15 is rotated by a motor (not shown).

  The paper cutting unit 8 is provided with a fixed blade 16 and a movable blade 17 for cutting the roll paper 3. As shown in FIG. 1, the fixed blade 16 and the movable blade 17 are provided at positions where the roll paper 3 is sandwiched therebetween and can be cut, and the rotary cutter that cuts the roll paper 3 by the rotation of the movable blade 17. Configure.

  The printer main body 1 includes a housing 20 and a cover 21 that covers the housing 20, and a platen roller 15 and the like are attached to the housing 20.

  Next, the basic operation of the printer P will be described. As shown in FIG. 1, when the platen roller 15 is rotationally driven and the roll paper 3 in contact with the platen roller 15 is fed in the transport direction along with the rotation of the platen roller 15, the roll paper 3 is pulled out from the hopper 9 and the platen roller It is conveyed to the 15 side. At this time, the roll paper 3 in the hopper 9 rotates in the direction of arrow L in FIG. 1, and the support rollers 10 and 11 rotate in the direction of arrow R in FIG. When the roll paper 3 is conveyed to the platen roller 15, printing is performed on the roll paper 3 supported by the platen roller 15 by the thermal head 14. The platen roller 15 is intermittently driven to feed the roll paper 3 in the transport direction every time printing is performed on the roll paper 3.

  The roll paper 3 on which printing has been performed by the thermal head 14 is subsequently conveyed toward the paper discharge direction by the rotational drive of the platen roller 15. When the roll paper 3 passes the position of the paper cutting unit 8, the rotation of the platen roller 15 is stopped. Then, the movable blade 17 provided in the paper cutting unit 8 is driven to rotate, and the roll paper 3 sandwiched between the fixed blade 16 is cut. The roll paper 3 including the cut print portion is discharged as, for example, a receipt from a paper discharge port 4 provided at the downstream end of the guide path 5.

  Next, the platen roller support structure will be described. 4 is a plan view showing the platen roller support structure and its periphery, FIG. 5 is an exploded perspective view showing the platen roller support structure, and FIG. 6 is a side view showing a part of the support frame.

  The platen roller 15 includes a pair of shaft portions 51 and 52 provided at both ends of the platen roller 15, a pair of bearing members 53 provided on the pair of shaft portions 51 and 52, and one shaft portion 51. A platen roller unit 50 is configured together with a gear 54 fixed to the shaft, a pair of E-rings 55 provided at the tip ends of the pair of shaft portions 51 and 52, and the like. The platen roller unit 50 is detachably attached to the housing 20 and is positioned on the housing 20 by a pair of positioning members 60.

  The housing 20 has a pair of support frames 22 arranged to face each other while being separated from each other. Each of the support frames 22 is provided with a fitting hole 22a into which the bearing member 53 is fitted, and an opening 22b communicating with the fitting hole 22a. The opening 22b is formed in a shape that allows the shafts 51 and 52 of the platen roller unit 50 to pass therethrough and prevents the bearing member 53 from passing therethrough. Specifically, the width of the opening 22b is formed wider than the diameter of the shaft portions 51 and 52 and narrower than the diameter of a small diameter portion 53b described later of the bearing member 53. The fitting hole 22a communicates with the opening 22b so that the shafts 51 and 52 of the platen roller unit 50 can enter and exit through the opening 22b, and the bearing member 53 can be fitted and removed. Specifically, the opening 22b allows the shafts 51 and 52 of the platen roller unit 50 to enter and exit the fitting hole 22a in a direction orthogonal to the opposing direction of the pair of support frames 22, and the fitting hole 22a The bearing member 53 is allowed to be fitted and removed in the facing direction of the pair of support frames 22. The fitting hole 22a positions the bearing member 53 in a direction orthogonal to the facing direction of the pair of support frames 22.

  FIG. 7 is a plan view showing the platen roller support structure, FIG. 8 is a plan view showing the platen roller unit, and FIG. 9 is a plan view showing a part of the platen roller unit.

  The platen roller 15 is formed in a cylindrical shape. The peripheral surface of the platen roller 15 is made of an elastic member such as rubber and supports paper. The pair of shaft portions 51 and 52 are provided at both ends of the platen roller 15 coaxially with the platen roller 15.

  The shaft portions 51 and 52 are inserted through the bearing member 53. The bearing member 53 can move with respect to the shaft portions 51, 52 along the axial direction of the platen roller 15 (that is, the axial direction of the shaft portions 51, 52), and the platen roller 15 is moved via the shaft portions 51, 52. Support for rotation. The bearing member 53 is provided with a large-diameter portion 53a, a small-diameter portion 53b, and a through-hole 53c that penetrates the large-diameter portion 53a and the small-diameter portion 53b. The large diameter portion 53a contacts the outer surface of the support frame 22, and the small diameter portion 53b is fitted into the fitting hole 22a. The shaft portions 51 and 52 are inserted through the through holes 53c.

  The gear 54 is separated from the bearing member 53 and the positioning member 60 and is fixed to one shaft portion 51, and the power of the driving source (motor) is transmitted through the transmission gear to rotate the platen roller 15. The gear 54 is formed with a protrusion 54 a, which is in contact with the E-ring 55, and the E-ring 55 prevents the gear 54 from coming off the shaft 51.

  Grooves 51b and 52b are formed in the shaft portions 51 and 52, respectively, and the positioning member 60 is detachably attached to the grooves 51b and 52b. The groove 51b of the shaft portion 51 to which the gear 54 is fixed separates the bearing member 53 through which the shaft portion 51 is inserted from the gear 54 (FIG. 7). The groove 51b functions as a blocking portion that blocks the movement of the pair of support frames 22 in the opposing direction in one positioning member 60 attached to the shaft portion 51. Here, in the shaft portion 52 where the gear 54 is not provided, the E-ring 55 prevents the other positioning member 60 attached to the shaft portion 52 from moving in the opposing direction of the pair of support frames 22. Functions as a blocking unit.

  10 is a perspective view showing the positioning member, FIG. 11 is a side view showing the positioning member and the tool in a state where the shaft portion of the platen roller unit is sandwiched, and FIG. 12 is a side view showing the tool in the state where the positioning member is sandwiched. FIGS. 13A and 13B are explanatory diagrams for explaining a procedure for engaging the tool with the positioning member.

  The positioning member 60 can be attached to and detached from the shaft portions 51 and 52 in a direction orthogonal to the axial direction of the platen roller 15. The positioning member 60 is in contact with the bearing member 53 in a state of being attached to the shaft portions 51 and 52, and positions the platen roller 15 and the bearing member 53 in the opposing direction of the pair of support frames 22.

  As shown in FIGS. 10 and 11, the positioning member 60 includes a base body 60 b having a pair of elastic pieces 60 a that sandwich the shaft portions 51 and 52 with elastic force. Further, the positioning member 60 has a narrow width portion 60d formed at the base portion of the elastic piece 60a in the base body 60b and a narrow width portion 60d in the base body 60b. The positioning member 60 has a pair of protrusions 60c and is narrowed by the protrusions 60c. And a wide portion 60e having a wider width in the facing direction of the pair of elastic pieces 60a than the width portion 60d. The positioning member 60 is made of resin, for example. The positioning member 60 is attached to and detached from the grooves 51b and 52b of the shaft portions 51 and 52 with the elastic deformation of the pair of elastic pieces 60a. The positioning member 60 can be easily removed by a dedicated tool 70.

  As shown in FIGS. 11 and 12, the tool 70 includes a base portion 70a and a pair of elastic clamping pieces 70b that are formed to protrude from the base portion 70a. In the pair of elastic sandwiching pieces 70b, engaging portions 70d are formed at mutually facing portions 70c of the pair of elastic sandwiching pieces 70b. The pair of elastic clamping pieces 70b passes through the narrow portion 60d of the positioning member 60 by being moved along the axial direction of the platen roller 15 toward the positioning member 60 attached to the shaft portions 51 and 52. Then, the positioning member 60 is clamped. The engaging portion 70d is engaged with the protrusion 60c of the positioning member 60 by the movement of the pair of elastic clamping pieces 70b along the axial direction of the platen roller 15. Then, the engaging portion 70d moves in the direction in which the positioning member 60 is removed from the shaft portions 51 and 52, thereby removing the positioning member 60 from the shaft portions 51 and 52. Further, a round hole portion 70e is formed at the base portion of the pair of elastic clamping pieces 70b in the tool 70, and the pair of elastic clamping pieces 70b are opened well in a direction away from each other by the round hole portion 70e. I have to.

  When the positioning member 60 is removed from the platen roller unit 50 by the tool 70, first, the tool 70 is moved from above the positioning member 60 (FIG. 11) attached to the shaft portions 51 and 52 to the narrow width of the positioning member 60. The pair of elastic pieces 60a of the positioning member 60 are clamped by the pair of elastic clamping pieces 70b by moving toward the portion 60d and passing through the narrow width portion 60d ((a) in FIG. 13). In FIG. 13, the shaft portions 51 and 52 are not shown. From this state, the tool 70 is moved along the axial direction of the platen roller 15 and moved to the wide width portion 60e of the positioning member 60, and the pair of protrusions 60c of the positioning member 60 are paired with the pair of engaging portions 70d of the tool 70. Are engaged ((b) in FIG. 13). Then, the tool 70 is moved upward from this state. As a result, the protrusion 60c is pulled upward by the engaging portion 70d, and the positioning member 60 is detached from the shaft portions 51 and 52 (FIG. 12).

  A procedure for removing the platen roller 15 in the printer P having such a configuration will be described. FIG. 14 is an explanatory diagram for explaining a process of removing the platen roller. First, the positioning member 60 is pulled upward using the tool 70 in the above-described procedure and removed from the shaft portions 51 and 52 of the platen roller unit 50 ((a) in FIG. 14). Accordingly, the pair of bearing members 53 can move along the axial direction of the platen roller 15. Next, the pair of bearing members 53 are moved along the axial direction of the platen roller 15 and separated from the fitting holes 22a of the support frame 22 ((b) in FIG. 14). Thereby, the shaft portions 51 and 52 of the platen roller unit 50 can pass through the opening 22 b of the support frame 22. Next, the platen roller 15 (platen roller unit 50) is pulled upward so that the shaft portions 51 and 52 pass through the opening portion 22b of the support frame 22, and the shaft portions 51 and 52 are supported by a pair via the opening portion 22b. The platen roller 15 (platen roller unit 50) is separated from the pair of support frames 22 by being separated from the frame 22 ((c) in FIG. 14). The platen roller 15 (platen roller unit 50) can be attached to the pair of support frames 22 by a procedure reverse to this procedure.

  As described above, in the present embodiment, the positioning member 60 is removed from the shaft portions 51 and 52 provided at both ends of the platen roller 15, and the bearing member 53 is removed from the fitting holes 22 a of the pair of support frames 22. Thus, the shaft portions 51 and 52 can pass through the opening 22b. As a result, the shaft portions 51 and 52 can be detached from the pair of support frames 22 via the opening 22 b, and the platen roller 15 can be detached from the pair of support frames 22. Therefore, the platen roller 15 can be removed from the pair of support frames 22 relatively easily.

  In the present embodiment, both the pair of bearing members 53 can move relative to the shaft portions 51 and 52 along the axial direction of the platen roller 15, and the positioning member 60 is provided for each bearing member 53. It has been. Therefore, the platen roller 15 can be removed from the pair of support frames 22 more easily than when one of the bearing members is not movable along the axial direction of the platen roller 15.

  In the present embodiment, the gear 54 that transmits the power of the drive source (motor) and rotates the platen roller 15 is fixed to one shaft 51, and the shaft 51 to which the gear 54 is fixed is inserted. The bearing member 53 thus made can move with respect to the shaft portion 51 along the axial direction of the platen roller 15. And the groove | channel 51b which is a prevention part spaces apart the bearing member 53 and the gearwheel 54 in which the axial part 51 to which the gearwheel 54 was fixed was penetrated. Therefore, the positioning accuracy of the bearing member 53 can be increased while avoiding the influence of the mounting accuracy of the gear 54 on the positioning of the bearing member 53.

  In the present embodiment, the positioning member 60 includes a base body 60b having a pair of elastic pieces 60a that sandwich the shaft parts 51 and 52 by elastic force, and a narrow width part formed at the base of the elastic piece 60a in the base body 60b. 60d and a wide portion 60e that is connected to the narrow width portion 60d in the base body 60b, has a pair of protrusions 60c, and has a wider width in the opposing direction of the pair of elastic pieces 60a than the narrow width portion 60d. And can be removed by the tool 70. The tool 70 is moved along the axial direction of the platen roller 15 toward the positioning member 60 attached to the shaft portions 51 and 52, thereby passing the narrow width portion 60 d and sandwiching the positioning member 60. The pair of elastic sandwiching pieces 70b and the pair of elastic sandwiching pieces 70b that are formed in the mutually facing portions 70c are engaged with the protrusions 60c by the movement of the pair of elastic sandwiching pieces 70b along the axial direction of the platen roller 15. And an engaging portion 70d for removing the positioning member 60 from the shaft portions 51 and 52 by moving in the direction in which the positioning member 60 is removed from the portions 51 and 52. Therefore, the positioning member 60 can be easily removed using the tool 70.

  The present invention is not limited to this embodiment, and various other embodiments can be adopted without departing from the gist of the present invention. For example, at least one of the pair of bearing members 53 only needs to be movable with respect to the shaft portions 51 and 52 along the axial direction of the platen roller 15. When the other bearing member 53 cannot move with respect to the shaft portions 51 and 52 along the axial direction of the platen roller 15, the other bearing member 53 is moved by moving the platen roller 15 in the axial direction. The fitting hole 22a can be attached and detached.

3. Roll paper (recording medium)
14 ... Thermal head (printing head)
DESCRIPTION OF SYMBOLS 15 ... Platen roller 22 ... Support frame 22a ... Fitting hole 22b ... Opening part 51,52 ... Shaft part
51b, 52b ... groove 53 ... bearing member
53a ... large diameter part
53b ... Small diameter part
53c ... through hole 54 ... gear
55 ... E-ring 60 ... positioning member 60b ... base 60c ... projection 60d ... narrow portion 60e ... wide portion 70 ... tool 70b ... elastic clamping piece 70d ... engagement portion P ... printer

JP 2002-144656 A

Claims (5)

A platen roller that supports the recording medium;
A pair of shaft portions provided at both ends of the platen roller;
A pair of E-rings provided at the distal ends of the pair of shafts;
A groove at least partially located between the platen roller and the E-ring in the shaft portion;
A large-diameter portion, a small-diameter portion whose outer diameter is smaller than the large-diameter portion and located on the platen roller side of the large-diameter portion, and a through-hole penetrating the large-diameter portion and the small-diameter portion are provided. The shaft portion is inserted into the platen roller, and at least one of the platen roller is movable between the platen roller and the E-ring along the axial direction of the platen roller, and the platen roller passes through the shaft portion. A pair of bearing members that rotatably support,
The shaft portion can pass through and the bearing member cannot pass through, and the opening portion communicates with the opening portion so that the shaft portion can go in and out through the opening portion and the small diameter portion can be fitted and removed. A pair of support frames, each of which is formed with a fitting hole and disposed opposite to each other,
A pair of the platen roller is attachable to and detachable from the groove in a direction perpendicular to the axial direction of the platen roller, and is in contact with the bearing member while being attached to the groove between the bearing member and the E-ring. A positioning member for positioning the platen roller and the bearing member in the opposing direction of the support frame;
Equipped with a,
The small diameter portion, a platen roller support structure, characterized in Hamada' capable der Rukoto into the fitting hole in the opposing direction of the pair of supporting frames. Both of the pair of bearing members are movable relative to the shaft portion along the axial direction of the platen roller.
The platen roller support structure according to claim 1, wherein the positioning member and the groove are provided for each of the bearing members. Wherein apart from the bearing member and positioning member is fixed, located on the opposite side of the platen roller side of the groove provided on the shaft of the one to the shaft portion of one of the grooved drive A gear for transmitting the power of the source and rotating the platen roller ;
The platen roller support structure according to claim 1 or 2, wherein the gear is prevented from coming off from the shaft portion by the E-ring . The positioning member includes a base having a pair of elastic pieces for sandwiching the shaft portion by elastic force, a narrow width portion formed at a base portion of the elastic piece in the base, and a continuous portion to the narrow width portion in the base is, claims 1, wherein the benzalkonium have a wide wide portion in the opposing direction of the pair of elastic pieces than the narrow portion by the protrusion has a pair of projections 3 The platen roller support structure according to any one of the above. The platen roller support structure according to any one of claims 1 to 4,
A print head for printing on a recording medium supported by the platen roller;
A printer comprising:

Images