JP3829622B2 - Recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress rattling of a carriage guide shaft in the direction of the central axis and to rotate the carriage guide shaft well. SOLUTION: The recorder comprises a mechanism for adjusting the platen gap between a recording head and a platen by passing a carriage mounting a recording head over a lower carriage guide shaft 26 interposed between side frames and moving the lower carriage guide shaft relatively to the subframe through rotation using an eccentric cam 46 provided at the end part of the lower carriage guide shaft wherein a spring 72 is provided on the central axis 71 of the lower carriage guide shaft such that an urging force P acts in the direction along the central axis.

Description

[0001]
BACKGROUND OF THE INVENTION
According to the present invention, an eccentric cam is installed at the end of the carriage guide shaft, and the recording is provided with a platen gap adjusting mechanism for adjusting the platen gap by moving the carriage guide shaft in the platen direction by the rotation of the carriage guide shaft. Relates to the device.
[0002]
[Prior art]
In the recording head, a recording head having a large number of recording wires is mounted on a carriage that travels along the platen. The recording wire is moved between the recording head and the platen by projecting the recording wire toward the platen. A dot impact printer that records an image on a sheet is known.
[0003]
In such a printer, an eccentric cam is installed at the end of a carriage guide shaft that is mounted between a pair of subframes and passes through the carriage, and the eccentric cam is used to rotate the carriage guide shaft. Some include a platen gap adjusting mechanism that adjusts the platen gap between the recording head and the platen by moving the carriage guide shaft in the platen direction with respect to the subframe.
[0004]
In a printer equipped with this platen gap adjusting mechanism, a leaf spring or the like is disposed between the side frame and the eccentric cam in a state of being inserted into the carriage guide shaft or the like. In some cases, the traveling stability of the carriage (especially, the stability during acceleration in the initial stage of traveling of the carriage) is ensured by suppressing the rattling in the central axis direction.
[0005]
[Problems to be solved by the invention]
However, since the leaf spring or the like is disposed between the subframe and the eccentric cam in a state where it is inserted into the carriage guide shaft, when the carriage guide shaft is rotated to adjust the platen gap, The carriage guide shaft is rotated against the urging force from the leaf spring or the like. For this reason, there is a possibility that the moment required for the rotation of the carriage guide shaft increases and the carriage guide shaft cannot be rotated well.
[0006]
In addition, since the leaf spring or the like is disposed between the sub frame and the eccentric cam while being inserted into the carriage guide shaft, the eccentric cam or the like is used as the carriage guide shaft against the urging force of the leaf spring or the like. Must be installed. For this reason, the mounting work of the eccentric cam or the like becomes complicated, and the assembling property of the printer is lowered.
[0007]
An object of the present invention has been made in consideration of the above-described circumstances, and is a recording apparatus capable of suppressing the rattling of the carriage guide shaft in the central axis direction and rotating the carriage guide shaft satisfactorily. Is to provide.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, the carriage on which the recording head is mounted is inserted into the carriage guide shaft disposed between the main body frames, and the carriage is used by using the eccentric cam installed at the end of the carriage guide shaft. In a recording apparatus including a platen gap adjusting mechanism that adjusts a platen gap between the recording head and the platen by moving the carriage guide shaft with respect to the frame body by rotating the guide shaft.
A bias that applies a biasing force to a central axis of the carriage guide shaft at one end of the carriage guide shaft at one end of the carriage guide shaft so that an eccentric cam fixed to the carriage guide shaft is pressed against the main body frame. The body is provided.
[0009]
According to a second aspect of the present invention, in the first aspect of the present invention, the biasing body is installed in an externally attached state with respect to the carriage guide shaft.
[0010]
According to a third aspect of the present invention, in the first or second aspect of the present invention, the urging member presses the carriage guide shaft against the notch edge of the main body frame and is eccentric to a roller installed on the main body frame. It is characterized by being installed on a lever member for pressing the cam.
[0011]
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the urging body includes a spring base portion and a spring bent from the spring base portion and abutted against the guide shaft. A pressing force that acts on the carriage guide shaft from the lever member changes according to the amount of movement of the carriage guide shaft with respect to the main body frame, and from the biasing member to the central axis of the carriage guide shaft. The position where the urging body abuts on the guide shaft is set so that the urging force acting changes in inverse proportion to the pressing force.
[0012]
The invention described in claim 1 has the following action.
[0013]
Since an eccentric cam fixed to the carriage guide shaft is pressed against the main body frame, an urging body for applying an urging force in a direction along the central axis of the carriage guide shaft is provided at one end of the carriage guide shaft. The carriage guide shaft is pressed against the main body frame together with the eccentric cam, and rattling in the direction along the central axis of the carriage guide shaft can be suppressed. For this reason, traveling of the carriage along the carriage guide shaft can be stabilized.
[0014]
Further, since the urging force from the urging body in the direction along the central axis of the carriage guide shaft acts on the central axis of the carriage guide shaft, the moment when the carriage guide shaft is rotated against this urging force. Can be reduced. As a result, the carriage guide shaft can be rotated easily and satisfactorily, and the platen gap can be adjusted smoothly.
[0015]
The invention according to claim 2 has the following effects.
[0016]
Since the urging body is installed externally with respect to the carriage guide shaft, the urging body can be installed after attaching the eccentric cam or the like to the carriage guide shaft, so that the carriage resists the urging force of the urging body. The trouble of attaching an eccentric cam or the like to the guide shaft can be eliminated. For this reason, it becomes easy to attach an eccentric cam or the like to the carriage guide shaft, and assemblability can be improved.
[0017]
The invention according to claim 3 has the following effects.
[0018]
Since the urging body is installed on the lever member for pressing the carriage guide shaft against the notch edge of the main body frame and pressing the eccentric cam against the roller installed on the main body frame, the rotation of the carriage guide shaft and Since the lever member also rotates during movement relative to the main body frame, the relative movement amount of the biasing body fixed to the lever member and the carriage guide shaft is set smaller than when the biasing body is attached to the main body frame. it can. As a result, the amount of wear of the urging body and the carriage guide shaft can be reduced.
[0019]
The invention according to claim 4 has the following effects.
[0020]
The pressing force that acts on the carriage guide shaft from the lever member changes according to the amount of movement of the carriage guide shaft relative to the main body frame, and the biasing force that acts on the central axis of the carriage guide shaft from the biasing member is applied to the pressing force. Since the position of the urging member that contacts the guide shaft is set so as to change inversely, the carriage guide shaft is rotated to adjust the platen gap and moved relative to the powder frame. The addition is set almost uniformly regardless of the size of the platen gap. As a result, it is possible to satisfactorily adjust the platen gap.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0022]
[A] One embodiment (FIGS. 1 to 19)
FIG. 1 is a perspective view showing a printer main body of a dot impact printer to which an embodiment of a recording apparatus according to the present invention is applied. FIG. 2 is a side sectional view of the printer main body of FIG.
[0023]
The printer 10 as a recording apparatus shown in these drawings prints an image including characters by hitting a number of recording wires of a recording head against a sheet via an ink ribbon (both not shown) to record dots. Dot impact printer. The printer 10 includes a printer main body 11 as a recording apparatus main body, a push tractor unit 12 attached to the printer main body 11, an upper case (not shown) and a lower case 13 that cover the upper and lower sides of the printer main body 11, respectively, And a sheet supply guide 43 that is installed on the front side of the main body 11 and guides the cut sheet K.
[0024]
The sheet includes the cut sheet K cut to a predetermined length and a continuous sheet in which a plurality of sheets are connected. Examples of the cut sheet K include cut paper, copy paper, and cut film, and examples of the continuous sheet include continuous paper.
[0025]
The printer main body 11 includes a base frame 14 as a main body frame, a main frame 15, a left side frame 16 and a right side frame 17, a recording head 18 and a carriage 19 as recording mechanisms, and a platen 20 as a sheet conveying mechanism. , A sheet guide 25, a first transport roller 21, a second transport roller 22, a third transport roller 23, and a fourth transport roller 24.
[0026]
A left side frame 16 and a right side frame 17 are erected and fixed at substantially both ends of the base frame 14 and the main frame 15. A lower carriage guide shaft 26 and an upper carriage guide shaft 27 are spanned between the left side frame 16 and the right side frame 17 at a predetermined distance in the vertical direction. Among these, the lower carriage guide shaft 26 is pivotally supported by the left side frame 16 and the right side frame 17. Further, a platen 20 is bridged between the left side frame 16 and the right side frame 17 and is rotatably disposed, and a seat guide 25 is fixedly disposed.
[0027]
The push tractor unit 12 shown in FIG. 2 supplies a continuous sheet (for example, continuous paper) to the sheet transport mechanism unit including the platen 20 and has a pair of left and right tractors 28. These tractors 28 include a tractor drive pulley (not shown) that is rotatably supported on the tractor drive shaft 29 and is slidable in the axial direction, and a tractor 28 that is rotatably supported on the tractor guide shaft 30 and slidable in the axial direction. A tractor belt 31 is wound around the tractor driven pulley (not shown) and a sheet pressing lid 32 is provided.
[0028]
The distance between the pair of tractors 28 can be adjusted according to the width dimension of the continuous sheet (continuous paper) to be conveyed. A plurality of pins 33 projecting from the entire outer periphery of the tractor belt 31 can be engaged with holes (not shown) drilled on both sides in the width direction of the continuous sheet.
[0029]
In the sheet transport mechanism including the platen 20, the first transport roller 21 and the second transport roller 22 are located on the front side of the printer main body 11, and the third transport roller 23 and the fourth transport roller 24 are connected to the printer main body. 11 is arranged on the rear side of each. Further, the first conveyance roller 21 and the second conveyance roller 22, and the third conveyance roller 23 and the fourth conveyance roller 24 are arranged in the vertical direction to make a pair.
[0030]
Among these, the first conveyance roller 21 and the third conveyance roller 23 are arranged below the sheet guide 25 together with the platen 20, and the second conveyance roller 22 and the fourth conveyance roller 24 are arranged above the sheet guide 25. The upper portions of the platen 20, the first conveyance roller 21, and the third conveyance roller 23 are in a state of protruding above the sheet guide 25. Further, a sheet holding plate 37 that holds a sheet with the sheet guide 25 is provided on the front side of the printer body 11 in the sheet guide 25.
[0031]
The platen 20, first transport roller 21, second transport roller 22, third transport roller 23, and fourth transport roller 24 are driven clockwise (CW) or counterclockwise (CCW) in FIG. Is driven to rotate. Similarly, the tractor belt 31 of the push tractor unit 12 is driven counterclockwise by the drive wheel train 34.
[0032]
The drive wheel train 34 shown in FIG. 1 is installed on one of the left side frame 16 and the right side frame 17, for example, the right side frame 17. The drive wheel train 34 includes a motor pinion 36 that is rotatably and integrally fixed to a drive shaft of a sheet supply motor 35 that can rotate forward or reverse. The driving force from the motor pinion 36 is wound around the platen 20, the first conveying roller 21, the second conveying roller 22, the third conveying roller 23, the fourth conveying roller 24, and the push tractor via a transmission mechanism and a gear mechanism. Transmission to the unit 12 is possible.
[0033]
As shown in FIG. 2, the cut sheet K such as cut sheet or copy paper is manually supplied from the front side of the printer main body 11, and then the clockwise rotation of the platen 20, the first conveyance roller 21, and the third conveyance roller 23. And the counterclockwise rotation of the second transport roller 22 and the fourth transport roller 24, the printer body 11 is transported in the direction of arrow A from the front to the rear, and the platen 20 and the first transport roller 21 are also transported. The third conveyance roller 23 is conveyed counterclockwise and the second conveyance roller 22 and the fourth conveyance roller 24 are rotated in the arrow B direction from the rear to the front of the printer body 11.
[0034]
On the other hand, a continuous sheet such as continuous paper is supplied in the direction of arrow B from the rear side of the printer main body 11 by the push tractor unit 12, and then the platen 20, the first transport roller 21, the second transport roller 22, and the third transport roller. 23 and the fourth conveying roller 24 are conveyed in the same direction (arrow B direction).
[0035]
As a result, the cut sheet K and the continuous sheet are conveyed in the sub-scanning direction orthogonal to the later-described main scanning direction of the carriage 19.
[0036]
As shown in FIG. 1, the carriage 19 is slidably inserted into the lower carriage guide shaft 26 and the upper carriage guide shaft 27 and has the recording head 18 mounted thereon. Since the lower carriage guide shaft 26 and the upper carriage guide shaft 27 are arranged in parallel with the platen 20, the carriage 19 performs main scanning that coincides with the axial directions of the platen 20, the lower carriage guide shaft 26 and the upper carriage guide shaft 27. It is provided so that it can run (scan) in the direction.
[0037]
The carriage 19 is coupled to a timing belt 39 (FIG. 2) that is reciprocated by forward rotation or reverse rotation of a carriage drive motor 38. Accordingly, the carriage 19 is guided to the lower carriage guide shaft 26 and the upper carriage guide shaft 27 via the timing belt 39 by the forward or reverse rotation of the carriage drive motor 38, and is directed leftward or rightward in FIG. 1 in the main scanning direction. Scanned. Here, the carriage drive motor 38 is configured by a stepping motor, for example, together with the sheet supply motor 35.
[0038]
As shown in FIG. 1, the carriage 19 is provided with a ribbon cassette mounting portion 40, and a ribbon cassette (both not shown) storing ink ribbons is mounted on the ribbon cassette mounting portion 40. Further, the carriage 19 is provided with a ribbon mask holder 41 that protects the ink ribbon of the ribbon cassette from a sheet (cut sheet or continuous sheet) conveyed in contact with the upper peripheral surface of the platen 20. The ink ribbon in the ribbon cassette is movably provided in front of the recording wire of the recording head 18 by a ribbon driving shaft 42 installed in the ribbon cassette mounting portion 40.
[0039]
The recording head 18 includes a large number of recording wires (not shown), and the ink ribbon is positioned in front of the protruding direction of these recording wires as described above. While the recording head 18 is scanned in the main scanning direction together with the carriage 19, the recording wire protrudes and strikes the ink ribbon. The ink on the ink ribbon is placed between the platen 20 (FIG. 2) and the recording head 18. Attached to a sheet (cut sheet K or continuous sheet) conveyed on the sheet, an image including characters is recorded on the sheet.
[0040]
In the recording operation by the recording head 18, one line sentence is recorded by the recording wire of the recording head 18 while the carriage 19 is scanned leftward or rightward in the main scanning direction, and the sheet is recorded each time the one line sentence is recorded. Is a cut sheet K, the sheet transport mechanism (platen 20, first transport roller 21, second transport roller 22, third transport roller 23, and fourth transport roller 24), and the sheet is a continuous sheet In this case, the sheet conveying mechanism and the push tractor unit 12 convey the sheet by a predetermined length (for the normal line interval) and repeat these operations.
[0041]
The carriage drive motor 38 shown in FIG. 1 is installed and supported on a substantially box-shaped motor mounting bracket 44 fixed to the right side frame 17.
[0042]
2 and 3, the printer 10 moves the lower carriage guide shaft 26 toward the platen 20 by rotating the lower carriage guide shaft 26, and moves the carriage 19 relative to the platen 20. A platen gap adjusting mechanism 45 that moves in the vertical direction and adjusts the platen gap between the recording head 18 mounted on the carriage 19 and the platen 20 according to the sheet thickness is provided. At this time, the upper carriage guide shaft 27 fits and supports the carriage 19 so as to be movable in the direction perpendicular to the platen 20, and thus the movement of the carriage 19 is not restricted.
[0043]
4 and 9, the platen gap adjusting mechanism 45 includes an eccentric cam 46, a rotating roller 47, a lever member 48, a platen gap adjusting motor 49, an output gear 50, and reduction gears 51, 52 and 53. Configured.
[0044]
The eccentric cam 46 is rotatably and integrally fixed to both ends of the lower carriage guide shaft 26. The eccentric cam 46 has a substantially semicircular shape as shown in FIGS. 5 and 10 and is configured such that the radius of the outer peripheral surface 54 gradually changes. For example, if the radii at both ends are Ra and Rc, and the central radius is Rb, then Ra>Rb> Rc. An outer peripheral surface 54 of the eccentric cam 46 is provided so as to be able to contact the rotating roller 47 that is rotatably supported by the left side frame 16 and the right side frame 17.
[0045]
Here, as shown in FIGS. 6 and 11, both end portions of the lower carriage guide shaft 26 are inserted into frame cutouts 55 and 56 formed in the left side frame 16 and the right side frame 17, respectively, so as to be lever members. The lever notch 62 of the lever 48 and the lever notch 63 of the lever member 58 (both will be described later) are inserted, and the eccentric cam 46 is fixed to the outside thereof. The frame notches 55 and 56 include front edges 55A and 56A formed in a direction perpendicular to the platen 20, respectively. Further, as shown in FIGS. 7 and 8, the eccentric cam 46 is rotationally integrated with the lower carriage guide shaft 26 by using a mounting screw 57.
[0046]
As shown in FIGS. 4 to 6, the lever member 58 has a base portion 58 </ b> A attached to the right side frame 17 using a support pin 59 so as to be rotatable. A tension spring 66 is interposed between the standing portion 58B of the lever member 58 and the locking portion 60 suspended from the right side frame 17. The tension spring 66 gives the lever member 58 a force that rotates around the support pin 59 in the direction of arrow M in FIGS.
[0047]
A lever notch 63 is formed in the base member 58 </ b> A in the lever member 58, and one end of the lower carriage guide shaft 26 is inserted into the lever notch 63. The lever notch 63 has a working edge 65 on the support pin 59 side. The action edge 65 of the lever member 58 applies a pressing force F to the lower carriage guide shaft 26 when the turning force in the direction of arrow M is applied to the lever member 58 by the tensile force of the tension spring 66. The component force Fx of the pressing force F constantly presses the lower carriage guide shaft 26 against the front edge 56A of the frame notch 56, and the component force Fy of the pressing force F causes the eccentric cam 46 fixed to the lower carriage guide shaft 26 to move. Always pressed against the rotating roller 47.
[0048]
Therefore, one end of the lower carriage guide shaft 26 is sandwiched between the working edge 65 of the lever member 58 and the front edge 56A of the frame notch 56 of the right side frame 17.
[0049]
Further, as shown in FIGS. 10 and 11, the lever member 48 has a base portion 48 </ b> A attached to the left side frame 16 so as to be rotatable using a support pin 59. A tension spring 61 is interposed between the standing portion 48B of the lever member 48 and a locking portion (not shown) suspended from the left side frame 16. The tension spring 61 gives the lever member 48 a force that rotates around the support pin 59 in the direction of arrow N in FIGS.
[0050]
A lever notch 62 is formed in the base member 48 </ b> A in the lever member 48, and the other end portion of the lower carriage guide shaft 26 is inserted into the lever notch 62. The lever notch 62 includes a working edge 64 on the support pin 59 side. The action edge 64 of the lever member 48 applies a pressing force G to the lower carriage guide shaft 26 when the turning force in the direction of arrow N is applied to the lever member 48 by the tensile force of the tension spring 61. The component force Gx of the pressing force G constantly presses the lower carriage guide shaft 26 against the front edge 55A of the frame notch 55, and the component force Gy of the pressing force G causes the eccentric cam 46 fixed to the lower carriage guide shaft 26 to move. Always pressed against the rotating roller 47.
[0051]
For this reason, the other end portion of the lower carriage guide shaft 26 is sandwiched between the working edge 64 of the lever member 48 and the front edge 55A of the frame notch 55 of the left side frame 16.
[0052]
The platen gap adjusting motor 49 is fixed to the left side frame 16 as shown in FIGS. 9 and 10, and the output gear 50 is fixed to the output shaft so as to rotate together. The reduction gear 51 meshes with the output gear 50. The reduction gear 52 is formed integrally with the reduction gear 51 and meshes with the reduction gear 53. The reduction gear 53 is fixed to the other end of the lower carriage guide shaft 26 so as to rotate together.
[0053]
Accordingly, the driving force of the platen gap adjusting motor 49 is transmitted to the lower carriage guide shaft 26 via the output gear 50 and the reduction gears 51, 52 and 53, and the lower carriage guide shaft 26 rotates. At this time, the outer peripheral surface 54 of the eccentric cam 46 is always pressed by the rotating roller 47, and the lower carriage guide shaft 26 is always pressed by the front edge 55A of the frame notch 55 and the front edge 56A of the frame notch 56. As the lower carriage guide shaft 26 rotates, the lower carriage guide shaft 26 moves in the direction perpendicular to the platen 20 along the front edges 55A and 56A by an amount corresponding to the radius difference of the eccentric cam 46. As a result, the recording head 18 is brought into contact with and separated from the platen 20 via the carriage 19, and the platen gap is adjusted within a range of, for example, 3 mm at maximum.
[0054]
Specifically, as shown in FIGS. 4 to 6 and 9 to 11, when the position corresponding to the radius Rb on the outer peripheral surface 54 of the eccentric cam 46 is in contact with the rotating roller 47, the platen gap is moderate. Is set. As shown in FIGS. 12 to 15, when the position corresponding to the radius Rc on the outer peripheral surface 54 of the eccentric cam 46 is in contact with the rotating roller 47, the platen gap is set wide. Further, as shown in FIGS. 16 to 19, when the position corresponding to the radius Ra on the outer peripheral surface 54 of the eccentric cam 46 is in contact with the rotating roller 47, the platen gap is set narrow.
[0055]
When adjusting the platen gap, the lower carriage guide shaft 26 moves along the front edge 55A of the frame notch 55 and the front edge 56A of the frame notch 56 only in the direction perpendicular to the platen 20, and in the front-rear direction of the printer 10. Do not move. For this reason, since the recording head 18 of the carriage 19 inserted through the lower carriage guide shaft 26 is held at an appropriate position with respect to the apex of the platen 20, good recording is ensured by the recording head 18.
[0056]
As shown in FIGS. 4, 7, and 8, an urging spring 72 as an urging member having an L shape in side view is attached to the standing portion 58 </ b> B of the lever member 58 with respect to the lower carriage guide shaft 26. Fixed in the attached state. The spring base portion 67 of the biasing spring 72 is fixed to the standing portion 58 </ b> B of the lever member 58 using the mounting screw 73. Then, the spring standing portion 68 of the urging spring 72 abuts on the apex 70 of the conical portion 69 formed at the end of one end of the lower carriage guide shaft 26 and applies an urging force P to the apex 70.
[0057]
Since the apex 70 is located on the center axis 71 line of the lower carriage guide shaft 26, the spring standing portion 68 of the biasing spring 72 is aligned with the center axis 71 of the lower carriage guide shaft 26. The urging force P along is applied. This urging force P prevents rattling of the lower carriage guide shaft 26 in the direction of the central axis 71 (girder direction).
[0058]
Therefore, according to the above embodiment, the following effects (1) to (4) are obtained.
[0059]
(1) Since the urging force P in the direction along the central axis 71 of the lower carriage guide shaft 26 acts on the lower carriage guide shaft 26 from the urging spring 72, the urging force P in the direction along the central axis 71 of the lower carriage guide shaft 26 The rattling can be suppressed. For this reason, traveling of the carriage 19 along the lower carriage guide shaft 26, for example, traveling during acceleration at the initial stage of traveling can be stabilized.
[0060]
(2) Since the biasing force P from the biasing spring 72 in the direction along the central axis 71 of the lower carriage guide shaft 26 acts on the central shaft 71 (vertex 70) of the lower carriage guide shaft 26, this biasing force P The moment when the lower carriage guide shaft 26 is rotated against this can be reduced. As a result, the lower carriage guide shaft 26 can be rotated easily and satisfactorily, and the platen gap can be adjusted smoothly.
[0061]
(3) Since the biasing spring 72 is installed on the lever member 58 in an externally attached state with respect to the lower carriage guide shaft 26, the biasing spring 72 is biased after the eccentric cam 46 and the lever member 58 are attached to the lower carriage guide shaft 26. Since the spring 72 can be installed, the trouble of attaching the eccentric cam 46 and the lever member 58 to the lower carriage guide shaft 26 against the biasing force P of the biasing spring 72 can be eliminated. For this reason, the eccentric cam 46, the lever member 58, and the like can be easily attached to the lower carriage guide shaft 26, and the assemblability of the printer 10 can be improved.
[0062]
(4) The lower carriage guide shaft 26 is pressed against the front edge 55A of the frame cutout 55 of the left side frame 16 and the front edge 56A of the frame cutout 56 of the right side frame 17, and the left side frame 16 and the right side frame 17 are respectively Among the lever member 48 and lever member 58 for pressing the eccentric cam 46 against the rotating roller 47 installed on the lever member 58, the biasing spring 72 is installed on the lever member 58. Therefore, in order to adjust the platen gap, the lower carriage When the guide shaft 26 is rotated, and the lower carriage guide shaft 26 is moved along the front edge 55A of the frame notch 55 and the front edge 56A of the frame notch 56 (for example, 3 mm at the maximum), the lever member 58 is also rotated. . For example, when the platen gap is set wide, as shown in FIGS. 12 and 13, the lever member 58 is rotated in the direction of arrow M by the tensile force of the tension spring 66, and when the platen gap is set narrow, FIG. As shown in FIGS. 16 and 17, the lever member 58 rotates in the direction opposite to the arrow M against the tensile force of the tension spring 66. For this reason, the relative movement amount of the urging spring 72 fixed to the lever member 58 and the apex 70 of the lower carriage guide shaft 26 is set smaller than when the urging spring 72 is directly attached to the right side frame 17. (For example, up to 1 mm) As a result, the amount of wear of the biasing spring 72 and the lower carriage guide shaft 26 can be reduced.
[0063]
[B] Other embodiment (FIG. 20)
FIG. 20 is a schematic cross-sectional view showing a biasing spring and the like in another embodiment of the recording apparatus according to the present invention. In other embodiments, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.
[0064]
The biasing spring 80 of this other embodiment is formed by bending the spring standing portion 68 of the biasing spring 72 shown in FIG. The installation portion 82 is formed to be bent at an obtuse angle with respect to the spring base portion 81.
[0065]
The apex 70 of the conical portion 69 of the lower carriage guide shaft 26 is positioned at an intermediate position in the spring standing portion 82 of the urging spring 80 when the platen gap is intermediate, and the urging force from the urging spring 80 is increased. The power P is moderate. On the other hand, when the platen gap is wide, the apex 70 of the lower carriage guide shaft 26 is positioned on the tip side away from the spring base portion 81 in the spring standing portion 82 of the biasing spring 80. Is set large. Further, when the platen gap is narrow, the apex 70 of the lower carriage guide shaft 26 is positioned at a position close to the spring base portion 81 in the spring standing portion 82 of the biasing spring 80. The biasing force P is set small.
[0066]
That is, when the platen gap is wide and the lower carriage guide shaft 26 is separated from the platen 20, the tensile force of the tension springs 66 and 61 acting on the lever members 58 and 48, respectively, decreases as shown in FIGS. Further, the pressing forces F and G acting on the lower carriage guide shaft 26 from the lever members 58 and 48 are also reduced, and the load for rotating the lower carriage guide shaft 26 and moving it away from the platen 20 is also increased. Decrease. For this reason, the urging force P applied from the urging spring 80 to the lower carriage guide shaft 26 is set large, and the load for the rotation and movement of the lower carriage guide shaft 26 is increased.
[0067]
Further, when the platen gap is narrow and the lower carriage guide shaft 26 is close to the platen 20, the tension forces of the tension springs 66 and 61 acting on the lever members 58 and 48, respectively, as shown in FIGS. The pressing forces F and G acting on the lower carriage guide shaft 26 from the lever members 58 and 48 are also increased, and the load for rotating the lower carriage guide shaft 26 and approaching the platen 20 is also increased. Increase. For this reason, the urging force P applied from the urging spring 80 to the lower carriage guide shaft 26 is set to be small so as to avoid an increase in the load for the rotation and movement of the lower carriage guide shaft 26.
[0068]
In this way, the urging force P acting from the urging spring 80 to the lower carriage guide shaft 26 is the tensile force acting from the tension springs 66 and 61 to the lever members 58 and 48, that is, from the lever members 58 and 48 to the lower carriage guide. The biasing spring 80 functions as a balance spring, and the lower carriage guide shaft 26 rotates and moves toward and away from the platen 20 by being set to change in inverse proportion to the pressing forces F and G acting on the shaft 26. The hourly load is almost constant.
[0069]
Therefore, according to the other embodiment described above, the following effect (5) is obtained in addition to the effects (1) to (4) of the embodiment.
[0070]
(5) The pressing forces F and G acting on the lower carriage guide shaft 26 from the lever member 58 are applied to the front edge 56A of the frame notch 56 and the front edge 55A of the frame notch 55 when the platen gap is adjusted. The urging force P acting on the central axis 71 (vertex 70) of the lower carriage guide shaft 26 from the urging spring 80 changes in inverse proportion to the pressing forces F and G. Since the spring standing portion 82 of the biasing spring 80 is bent at an obtuse angle with respect to the spring base portion 81, the lower carriage guide shaft 26 is rotated to adjust the platen gap, and the frame notch 56 The load when moving along the front edge 56A and the front edge 55A of the frame notch 55 can be made substantially constant regardless of the size of the platen gap. As a result, it is possible to satisfactorily adjust the platen gap.
[0071]
As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this.
[0072]
【The invention's effect】
According to the recording apparatus of the present invention, the carriage on which the recording head is mounted is inserted into the carriage guide shaft disposed between the main body frames, and the eccentric cam installed at the end of the carriage guide shaft is used to In a recording apparatus having a platen gap adjusting mechanism for adjusting a platen gap between the recording head and a platen by moving the carriage guide shaft relative to the frame body by rotating the carriage guide shaft, A biasing body is provided at one end of the carriage guide shaft so as to press a fixed eccentric cam against the main body frame, and a biasing force is applied to the central axis of the carriage guide shaft in a direction along the central axis. Therefore, the carriage guide shaft is pressed against the body frame along with the eccentric cam, Suppresses rattling in the direction along the central axis of Jigaido axis, the carriage guide shaft can be satisfactorily rotated.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a printer main body of a dot impact printer to which an embodiment of a recording apparatus according to the invention is applied.
FIG. 2 is a side sectional view showing the printer main body of FIG.
FIG. 3 is a perspective view showing the platen gap adjusting mechanism of FIG. 1 together with a side frame.
4 is an enlarged perspective view showing a part of a right side frame and a platen gap adjusting mechanism in FIG. 3; FIG.
5 is a front view showing a part of the platen gap adjusting mechanism (a state in which the platen gap is intermediate) in FIG. 4 and the like. FIG.
6 is a front view showing a part of the platen gap adjusting mechanism of FIG. 5 excluding an eccentric cam. FIG.
7 is a cross-sectional view taken along line VII-VII in FIG.
8 is a cross-sectional view taken along line VIII-VIII in FIG.
9 is an enlarged perspective view showing the other part of the left side frame and the platen gap adjusting mechanism in FIG. 3;
10 is a front view showing the other part and the like of the platen gap adjusting mechanism (a state in which the platen gap is intermediate) in FIG. 9; FIG.
11 is a front view showing the other part of the platen gap adjusting mechanism of FIG. 10 excluding the eccentric cam and various gears. FIG.
12 is a front view showing a part of the platen gap adjusting mechanism in FIG. 5 when the platen gap is set wide.
13 is a front view showing a part of the platen gap adjusting mechanism of FIG. 12 excluding an eccentric cam. FIG.
14 is a front view showing the other part of the platen gap adjusting mechanism in FIG. 10 when the platen gap is set wide.
15 is a front view showing the other part of the platen gap adjusting mechanism of FIG. 14 excluding the eccentric cam and various gears.
16 is a front view showing a part of the platen gap adjusting mechanism in FIG. 5 when the platen gap is set narrow.
17 is a front view showing a part of the platen gap adjusting mechanism of FIG. 16 excluding an eccentric cam and various gears.
18 is a front view showing the other part and the like of the platen gap adjusting mechanism in FIG. 10 when the platen gap is set narrow.
FIG. 19 is a front view showing the other part of the platen gap adjusting mechanism of FIG. 18 except for the eccentric cam and various gears.
FIG. 20 is a schematic sectional view showing a biasing spring and the like in another embodiment of the recording apparatus according to the invention.
[Explanation of symbols]
10 printers (recording devices)
16 Left side frame 17 Right side frame 18 Recording head 19 Carriage 26 Lower carriage guide shaft 45 Platen gap adjustment mechanism 46 Eccentric cam 47 Rotating roller 48 Lever member 55, 56 Frame notch 55A, 56A Frame notch front edge 58 Lever member 61 Tension Spring 62, 63 Lever notch 64, 65 Lever notch working edge 66 Tension spring 68 Spring standing portion 70 Lower carriage guide shaft apex 71 Lower carriage guide shaft center axis 80 Biasing spring 82 Spring standing portions F, G Push Force P Energizing force

Claims (4)

A carriage on which the recording head is mounted is inserted into a carriage guide shaft disposed between the main body frames, and the carriage guide shaft is rotated by rotating the carriage guide shaft using an eccentric cam installed at the end of the carriage guide shaft. In a recording apparatus including a platen gap adjusting mechanism that moves a shaft with respect to the frame body to adjust a platen gap between the recording head and a platen.
A bias that applies a biasing force to a central axis of the carriage guide shaft at one end of the carriage guide shaft at one end of the carriage guide shaft so that an eccentric cam fixed to the carriage guide shaft is pressed against the main body frame. A recording apparatus provided with a body.   The recording apparatus according to claim 1, wherein the urging member is installed externally with respect to the carriage guide shaft.   2. The urging body is installed on a lever member for pressing a carriage guide shaft against a notch edge of a main body frame and pressing an eccentric cam against a roller installed on the main body frame. 2. The recording apparatus according to 2.   The biasing body has a spring base portion and a spring standing portion bent from the spring base portion and abutted against the guide shaft, and a pressing force acting on the carriage guide shaft from the lever member is The guide of the urging body changes according to the amount of movement of the carriage guide shaft relative to the main body frame, and the urging force acting on the central axis of the carriage guide shaft from the urging body changes in inverse proportion to the pressing force. The recording apparatus according to claim 1, wherein a position in contact with the shaft is set.

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