JP2005254479A - Carriage driving device and recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carriage driving device which can make a moving speed of a carriage constant at all times regardless of a device posture, and to provide a recording apparatus equipped with the carriage driving device. <P>SOLUTION: The carriage driving device comprises a friction force generating means 10 which generates a changeable friction force to a driving force transmitting means 150 for transmitting a driving force to the carriage 141. The friction force generating means changes the generation friction force according to the device posture. A change of a moving load of the carriage by the device posture can be negated by the friction force, and therefore the moving speed of the carriage can be made constant at all times without such an extra inertial load applied when a conventional counter weight is used. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a carriage driving device that drives a carriage and a recording apparatus including the carriage driving device.

  In general, an ink jet printer, which is one of recording apparatuses, includes a recording head mounted on a carriage that reciprocates in the main scanning direction, and a sheet conveying unit that intermittently conveys recording sheets by a set amount in the sub scanning direction. ing. Inkjet printers record information by ejecting ink droplets from the recording head onto the recording paper by moving the recording head along with the carriage in the main scanning direction while conveying the recording paper in the sub-scanning direction. .

  Such an ink jet printer is designed on the assumption that the printer is installed horizontally. For this reason, when the ink jet printer is installed in a state tilted from the horizontal direction, the carriage guide shaft is also tilted from the horizontal direction. May cause deterioration. In particular, since the carriage's own weight component is reversed depending on the carriage movement direction, that is, the difference between the forward path and the backward path, the influence of the difference is large. Therefore, an ink jet printer has been proposed in which a counterweight having substantially the same weight as the carriage is arranged so as to be parallel to the moving direction of the carriage and interlocked in the opposite direction, thereby canceling the weight component of the carriage. Yes.

JP-A-56-169081

  In the above-described conventional ink jet printer, since the carriage moving system always has a large inertia, not only the load of the driving source is increased, but also the accuracy of the carriage moving speed control itself may be lowered. is there.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a carriage driving device that can always keep the carriage moving speed constant regardless of the posture of the device, and a recording that includes the carriage driving device. To provide an apparatus.

  In order to achieve the above object, the carriage drive device of the present invention is a carriage drive device that reciprocates the carriage, and includes a driving force transmission means that transmits a driving force to the carriage, and a friction that can be changed to the driving force transmission means. And a frictional force generating means for generating a force, wherein the frictional force generating means changes the generated frictional force according to the posture of the apparatus. As a result, the change in carriage movement load due to the orientation of the device can be canceled out by frictional force, so there is no extra inertial load as with conventional counterweights, and the carriage movement speed is always constant. Can be.

  Further, the frictional force generating means includes a first mechanism that generates a frictional force only for the forward movement and a second mechanism that generates a frictional force only for the backward movement. . Thereby, even if the change in the movement load differs between the forward path and the return path of the carriage, it is possible to reliably cancel the change in each movement load. Further, the generated frictional force changes based on a moving direction component of its own weight of the carriage. Further, the generated frictional force is changed in such a manner as to cancel the self-weight component in conjunction with a change in a moving direction component of the self-weight of the carriage. The gradient of the change in the generated friction force is equal to the gradient of the change in the moving direction component of the carriage's own weight. Thereby, even if the apparatus posture is inclined at an arbitrary angle, the change in the movement load of the carriage can be canceled with certainty.

  The frictional force generating means includes a sliding contact means for generating a frictional force for a unidirectional movement, and a pressing force control means for controlling the pressing force by pressing the sliding contact means against the driving force transmitting means. It is characterized by having. Thereby, the frictional force generating means can be configured simply. The sliding contact means is a member that can rotate only in the forward direction, and when a force to rotate in the reverse direction acts from the driving force transmission means, a predetermined friction force is applied to the driving force transmission means. It is characterized by having a contact surface to be provided. The pressing force control means includes a weight member connected to the sliding contact means, a defining member for defining a direction of a force generated by the weight of the weight member, and biasing the sliding contact means to the driving force transmitting means. And an urging member. Thereby, since a frictional force generation means becomes a simple structure, cost can be restrained low.

  The sliding contact means is disposed so as to be slidable with a frictional force transmitting member provided on a pulley. The sliding contact means is arranged so as to be slidable with a frictional force transmitting member provided on a lead screw. Thereby, a frictional force can be directly generated with respect to the drive source of the carriage. The pressing force control means controls the pressing force based on a detection result of a sensor that detects an apparatus posture. As a result, the change in the movement load of the carriage can be more reliably canceled regardless of the angle of the apparatus posture. A recording apparatus for recording on a recording medium by a recording head mounted on a carriage, comprising the carriage driving devices. Thereby, a recording apparatus that exhibits the above-described effects can be provided.

  FIG. 1 is a perspective view of an external appearance configuration of an ink jet printer that is one of recording apparatuses according to an embodiment of the present invention when viewed from the front side, and FIG. The figure (B) shows the state at the time of use. In the following description, “left and right” and “front and rear” refer to directions when viewed from the front side of the ink jet printer. The ink jet printer 100 is a thin portable printer having a flat rectangular parallelepiped casing 110. The housing 110 includes a lower case 111 formed in a substantially planar shape and an upper case 112 having substantially the same dimensions as the lower case.

  The lower case 111 is formed in a container shape having an open upper surface, and stores the main components of the printer. The upper case 112 is formed in a container shape that is shallower than the lower case 111, and is coupled to the lower case 111 such that the open lower surface of the upper case 112 faces the open upper surface of the lower case 111. The lower case 111 and the upper case 112 are made of metal or plastic. When forming with a metal, it shape | molds integrally with a surrounding wall by press work etc., or it shape | molds separately and welds or adhere | attaches with an adhesive agent. In the case of forming with plastic, it is molded integrally with the peripheral wall by injection molding or the like, or is molded separately and bonded with an adhesive. The lower case 111 and the upper case 112 are coupled via a pair of frames 101 and 101a (see FIG. 2) that are separately attached to both sides by fastening with screws or snap fits (not shown).

  In order to improve the portability of the inkjet printer 100, the thickness dimension of the casing 110 including the lower case 111 and the upper case 112 is made as thin as possible, and the vertical and horizontal dimensions of the casing 110 are made as small as possible. In particular, the thickness dimension of the housing 110, that is, the accuracy of the gap between the lower case 111 and the upper case 112 is important. According to the above-described configuration, since the accuracy of the gap between the lower case 111 and the upper case 112 is determined only by the accuracy in the thickness direction of the frames 101 and 101a, the accuracy of the gap is easily obtained, and the accuracy management of the gap is also facilitated. . By adopting the snap-fit frame 101 and 101a, the removal and assembly of the lower case 111 and the upper case 112 can be simplified, so that errors such as paper jams and repairs such as replacement of parts can be performed quickly. Can be completed.

  Further, in the lower case 111, a substantially central portion on the front side of the peripheral wall is cut out as a paper discharge port 113, and a substantially central portion on the back side of the peripheral wall is cut out as an insertion / extraction port 114 for the ink cartridge. The upper case 112 has a rectangular paper feed port 115 formed in a substantially central portion. A paper feed door 116 having a size for closing the paper feed opening 115 is fitted into the paper feed opening 115. The paper feed door 116 is pivotally supported by the upper case 112 so as to be pivotable upward from the case surface within an acute angle range with the front end portion as an axis, and the rear end side is lifted by the turning so that the paper feed port 115 is opened. It has become.

  A paper holder 117 serving as a lid and a paper receiver is disposed on the upper case 112. The paper holder 117 is formed to have a size so as to cover the substantially central portion of the upper case 112 from the back side to the front side, and the lower case can be swung upwardly from the case surface in an obtuse angle range with the rear end as an axis. 111 is supported on the shaft. As shown in FIG. 1 (A), the paper holder 117 functions as a lid by turning forward and being fitted into a recess 118 formed from the back side to the front side at a substantially central portion of the upper case 112. As shown in FIG. 1 (B), it functions as a paper receiver by turning backward and stopping in a tilted state. Thereby, when the ink jet printer 100 is not used, the paper holder 117 can be stored compactly.

  In order to make the inkjet printer 100 having the above-described external configuration a highly portable thin printer, the arrangement positions of the main components of the printer housed in the gap between the lower case 111 and the upper case 112 have been devised. Yes. That is, each functional unit such as a paper supply unit, a paper discharge unit, a recording unit including a characteristic part of the present invention, a cartridge storage unit, a drive control unit, and a head ejection characteristic recovery unit constituting the printer is provided on the lower case 111. Are arranged directly adjacent to each other. Hereinafter, the details will be described with reference to the drawings.

  2 is a perspective view showing the internal structure of the ink jet printer 100, FIG. 3 is a plan view thereof, FIG. 4 is a sectional view taken along the line AA, FIG. 5 is a left side view of FIG. FIG. 5 is a perspective view showing a more detailed internal structure on the right side of the front surface. The ink jet printer 100 includes a sheet supply unit and a sheet discharge unit 120, a recording unit 140 including characteristic portions of the present invention, a cartridge storage unit 160, a drive control unit 170, a head ejection characteristic recovery unit 180, and the like. 111 is housed inside. Details of each functional unit will be sequentially described below.

  As shown in FIGS. 2 to 4, the paper supply unit and the paper discharge unit 120 pass from the paper holder 117 functioning as a paper receiver through the paper supply port 115 to the paper discharge port 113 through the recording stage 143. It has a function of transporting paper along the paper path, and the following members are arranged in order from the upstream side to the downstream side. That is, the movable paper guide top 121a fixed to the paper feed door 116 and the movable paper guide bottom 121b disposed opposite to each other below the movable paper guide top 121a via a link mechanism are opposed to each other with a predetermined interval therebetween. The fixed paper guide upper 122a and the fixed paper guide lower 122b, the one paper feed roller 123a and the plurality of driven rollers 123b arranged to be opposed to each other in the vertical direction, and the plurality of paper discharges arranged to be opposed to each other in the vertical direction. A star wheel 124a and one paper discharge roller 124b are disposed from the back side to the front side.

  The movable paper guide upper 121a and the movable paper guide lower 121b are formed of sheet metal, and are pivotally supported by the lower case 111 so as to be pivotable upward within an acute angle range from the surface of the lower case 111 with the front end as an axis. The rear end pivots up and down in conjunction with opening and closing of the holder 117. The fixed paper guide upper 122a and the fixed paper guide lower 122b are formed of sheet metal, and are fixed to the lower case 111 by fastening with screws or snap fits (not shown).

  The shaft of the paper feed roller 123a and the shaft of the paper discharge roller 124b are provided with a pair of frames 101 and 101a, which are separately mounted on both sides of the lower case 111, and bearings 123aa and 124bb shown in FIG. It is supported by the shaft. The frames 101 and 101a are made of plastic and are attached to the lower case 111 by fastening with screws or snap fits (not shown). The outer peripheral surface of the paper feed roller 123a is coated with rubber, ceramic particles or the like in order to increase the friction coefficient during conveyance, and the outer peripheral surface of the paper discharge roller 124b is plural in order to increase the friction coefficient during conveyance. The rubber roller is inserted. The paper feed roller 123a and the driven roller 123b are configured to sandwich and feed the paper inserted from the paper feed port 115.

  A plurality of driven rollers 123b are arranged along the axis below the paper feed roller 123a, and are locked to a driven roller pedestal 125 fixed to the lower case 111. The paper feed roller 123a is abutted and biased. A plurality of paper discharge star wheels 124 a are arranged along the axis of the paper discharge roller 124 b and are locked to a paper discharge star wheel pedestal 126 fixed to the lower case 111, and one is provided by a torsion coil spring or the like (not shown). The paper is urged against the paper discharge roller 123b every other time. The paper discharge star wheel 124a and the paper discharge roller 124b are configured to sandwich and feed the paper conveyed from the paper feed roller 123a and the driven roller 123b.

  In such a configuration, the paper passes from the paper holder 117 between the movable paper guide upper 121a and the movable paper guide lower 121b, and between the fixed paper guide upper 122a and the fixed paper guide lower 122b, and from the paper feed roller 123a to the recording stage. 143 is conveyed to the paper discharge roller 124b. Here, as shown by the alternate long and short dash line in FIG. 4, the sheet conveyance path L formed by the members 121 a and the like is formed to be substantially U-shaped. Accordingly, the paper in the middle of conveyance has a curved shape with the vicinity of the paper feed roller 123a as the lowermost end, so that the portion of the paper positioned between the paper feed roller 123a and the paper discharge roller 124b is pressed against the recording stage 143. It will be. For this reason, since the distance between the sheet portion on the recording stage 143 and the recording head 142 described later can always be kept constant, the recording accuracy can be improved.

  Further, as shown in FIGS. 2, 3, and 5, the paper supply unit and the paper discharge unit 120 include a paper feed motor 127 and a conveyance driving force transmission mechanism 130 disposed on the left side of the lower case 111. Yes. The paper feed motor 127 is attached to the frame 101 on the back side of the lower case 111 and between the left side surface of the lower case 111 and the movable paper guide lower 121b. For example, a DC motor or a stepping motor is provided. Is used.

  The transport driving force transmission mechanism 130 has a function of transmitting the driving force of the forward / reverse rotation of the paper feed motor 127 to the paper feed roller 123 a and the paper discharge roller 124 b to control the rotation, and from the back side of the lower case 111. The following members are arranged in order on the front side. That is, a first gear 131a fitted on the shaft of the paper feed motor 127, a second gear 131b attached to the frame 101 and meshed with the first gear 131a, a first pulley 132a fitted coaxially with the second gear 131b, The first tension pulley 132b attached to the frame 101, the second pulley 132c fitted on the shaft of the paper feed roller 123a, and the first pulley 132a are hung on the second pulley 132c via the first tension pulley 132b. A belt 133 is disposed.

  The third pulley 134a fitted coaxially with the second pulley 132c, the second tension pulley 134b attached to the frame 101, the fourth pulley 134c fitted on the shaft of the paper discharge roller 124b, and the third pulley 134a A belt 135 is provided that hangs around a fourth pulley 134c via a two-tension pulley 134b. A rotary encoder scale 128 for detecting the paper transport position is disposed coaxially with the second gear 131b. A rotary encoder 129 that reads the magnetic information of the rotary encoder scale 128 is attached to the frame 101. The transport driving force transmission mechanism 130 may use a gear train instead of the belt mechanism.

  According to the paper feed motor 127 and the conveyance driving force transmission mechanism 130 as described above, since the members are arranged substantially horizontally, the ink jet printer 100 can be thinned. Further, since the paper feed roller 123a, the paper discharge roller 124b, and the like are driven and controlled based on detection signals from the rotary encoder 129, the paper can be conveyed with high accuracy. As this paper, plain paper, special paper, recommended OHP sheet, glossy paper, glossy film, label sheet, government postcard, etc. can be used.

  As shown in FIGS. 2 to 4, the recording unit 140 including the characteristic part of the present invention has a function of recording on the part of the paper that has been conveyed onto the recording stage 143. The following members are arranged between the roller 123a and the paper discharge roller 124b on the fixed paper guide 122a and the movable paper guide 121a. In other words, a carriage 141 that can move in a direction perpendicular to the sheet conveyance direction (main scanning direction), a recording head 142 attached to the lower end surface of the carriage 141, and a recording stage 143 disposed along the moving direction below the carriage 141. A carriage guide shaft 144 that guides the movement of the carriage 141 and an ink tube 145 that connects the recording head 142 and the ink cartridge are disposed.

  The carriage 141 has a bearing portion 141a formed at the rear portion shown in FIG. 4 slidably inserted into the carriage guide shaft 144, and a leaf spring 141b attached to the front portion shown in FIG. The cradle 126 is slidably held. The carriage 141 is located at the standby position (home position) shown in FIGS. 2 and 3 when the ink jet printer 100 is in a non-recording state, ie, an off state or a standby state, and leaves the home position when the ink jet printer 100 is in a recording state. Thus, the carriage is reciprocally moved along the carriage guide shaft 144 and the paper discharge star wheel pedestal 126 by the carriage motor 146 and the like between both end portions of the conveyed paper.

  The recording head 142 includes a black ink recording head that discharges black ink, and a plurality of color ink recording heads that discharge ink of each color such as yellow, light cyan, cyan, light magenta, and magenta. The recording head 142 includes a plurality of pressure generation chambers connected to the ink tubes 145 for the respective colors and nozzles connected to them. For example, the pressure in the pressure generation chamber is changed by a piezoelectric element or a heating element to generate pressure. The ink stored in the room is ejected from the nozzle. In this embodiment, since the ink is pressurized and supplied from the ink tube 145, the inside of the recording head 142 is made negative by a pressure reducing valve to prevent ink leakage.

  The recording stage 143 is formed in a rectangular container shape extending between the paper feed roller 123a and the paper discharge roller 124b and below the carriage 141 in the moving direction. In the recording stage 143, an ink absorber (not shown) made of non-woven fabric, sponge, or the like is spread. The recording stage 143 is detachably attached to the lower case 111 by screws or snap fits (not shown). In particular, when performing so-called borderless printing, ink that has been removed from the paper out of the ejected ink is absorbed by the ink absorber, but when the amount of absorption approaches saturation, the entire recording stage 143 is easily removed. Therefore, the ink absorber can be easily replaced.

  The carriage guide shaft 144 is disposed above the fixed paper guide 122a. The carriage guide shaft 144 is axially supported by a pair of frames 101 and 101a that are separately attached to both sides of the lower case 111 at both ends. That is, the carriage guide shaft 144 is supported by a pair of frames 101 and 101a that support the shaft of the paper feed roller 123a and the paper discharge roller 124b, and is further abbreviated as the paper feed roller 123a and the paper discharge roller 124b. They are arranged on the same plane. Since the carriage guide shaft 144, the paper feed roller 123a, and the paper discharge roller 124b are arranged in this order from the upstream side of the conveyance, the carriage 141 does not interfere with the paper feed roller 123a. It is arranged so as to straddle.

  A frame for supporting a carriage guide shaft, a paper feed roller, and a paper discharge roller of a general printer is manufactured by bending one sheet metal. Each end of the paper feed roller and the paper discharge roller is attached to the same bent portion, but one end of the carriage guide shaft is attached to another bent portion. For this reason, if the flatness of the sheet metal or the bending accuracy of each bent portion is low, the shafts may be twisted or the parallelism between the shafts may be reduced.

  On the other hand, the frames 101 and 101a of the present embodiment are made of plastic, and both ends of the carriage guide shaft 144, the paper feed roller 123a, and the paper discharge roller 124b are attached to the same pair of frames 101 and 101a. It has been. Therefore, by controlling only the molding accuracy of the frames 101 and 101a, it is possible to prevent the twisting of each axis and maintain the parallelism between the axes with high accuracy. In addition, the carriage guide shaft 144, the paper feed roller 123a, and the paper discharge roller 124b of the present embodiment are arranged on substantially the same plane, and the carriage 141 straddles the paper feed roller 123a so as not to interfere with the paper feed roller 123a. Since the ink jet printer 100 is arranged in a shape, the inkjet printer 100 can be thinned.

  The ink tubes 145 are arranged on the upper surface of the movable paper guide 121a by bundling the tubes for the respective colors, each one end is connected to the corresponding ink cartridge 161, 162, and each other end corresponds. Each color recording head 142 is connected. The ink tube 145 sends the pressurized ink of each color from the ink cartridges 161 and 162 to the recording head 142. The ink tube 145 is arranged in a substantially U-shape on the upper surface of the movable paper guide 121a so that the ink tube 145 does not interfere with the carriage 141 and the like when the carriage 141 moves and does not bend or cross. Yes. The rear end of the movable paper guide 121a is bent in an approximately L shape, and the bent portion 121aa prevents the ink tube 145 from jumping out behind the movable paper guide 121a when the carriage 141 moves. It has a function of damming.

  Further, the recording unit 140 is provided with a carriage driving device. That is, as shown in FIGS. 2 to 4, a carriage motor (driving force transmitting means) 146 is disposed on the right side surface of the lower case 111, and a moving driving force transmitting mechanism (driving force transmitting means) 150 is a carriage guide shaft. The frictional force generating means 10 that is disposed along the line 144 and that is a characteristic part of the present invention shown in FIG. 7 is disposed on both sides of the moving drive force transmission mechanism 150. The carriage motor 146 is attached to the right side of the lower case 111 and behind the carriage 141. For example, a DC motor or a stepping motor is used.

  The movement driving force transmission mechanism 150 has a function of controlling the movement by transmitting the driving force of the forward / reverse rotation of the carriage motor 146 to the carriage 141, and is above the fixed paper guide 122 a and on the carriage guide shaft 144. The following members are disposed between the rear and carriage guide shaft 144 and the paper feed roller 123a. That is, the first pulley (driving force transmitting means) 151a shown in FIG. 6 fitted on the shaft of the carriage motor 146 and the second pulley (driving force transmitting means) 151b supported by the shaft in the vicinity of the left frame 101a It is disposed behind the guide shaft 144.

  Further, a carriage belt (driving force transmission means) 152 spanned between the pulleys 151a and 151b is disposed so as to rotate by passing above the fixed paper guide upper 122a and below the fixed paper guide 122b. That is, the sheet is disposed so as to pass through the rotating carriage belt 152. Thus, by providing the sheet conveyance path between the carriage belts 152 spanned between the pulleys 151a and 151b, the ink jet printer 100 can be thinned. As the belt mechanism, a toothed belt and a toothed pulley are preferable because of high accuracy, but a flat belt and a pulley may be used. The rear end portion of the fixed paper guide 122a is bent in a substantially L shape, and the bent portion 122aa does not protrude from the front of the fixed paper guide 122a and interfere with the carriage belt 152. It has a function to stop.

  Here, since the ink jet printer 100 according to the present embodiment is a thin printer with high portability, the ink jet printer 100 is easily used in a state inclined from the horizontal direction. In this case, since the carriage guide shaft 144 is also tilted from the horizontal direction and the own weight component of the carriage 141 is added to the moving direction, and the moving speed control becomes unstable, the frictional force generating means 10 that cancels the moving direction component of the own weight of the carriage 141 is provided. It is arranged.

  FIGS. 7A and 7B are a plan view and a top view showing details of the frictional force generating means 10. The frictional force generating means 10 includes a sliding contact means 11 that generates a frictional force with respect to movement in one direction, and a pressing force that controls the pressing force by pressing the sliding contact means 11 against the movement driving force transmission mechanism 150. Control means 12 is provided. The frictional force generating means 10 is provided on each side of the moving driving force transmission mechanism 150, and is coaxially and synchronously rotated with the moving driving force transmission mechanism 150, that is, the pulleys 151a and 151b. The disc-shaped frictional force transmission members 153a and 153b are configured to generate a variable frictional force.

  The slidable contact means 11 includes a roller 13 that can rotate only in the forward direction and a support member 14 that supports the roller 13. The pressing force control means 12 includes a weight (weight member) 15 having a supporting member 14 connected to one side surface, a cylindrical guide frame (regulating member) 16 having an open end in which the weight 15 is built, and a weight 15. A compression spring (biasing member) 17 is provided between the other side surface and the inner bottom surface of the guide frame 16. And the roller 13 is arrange | positioned so that an outer peripheral surface may contact | abut with the outer peripheral surface of the frictional force transmission members 153a and 153b. The weight 15 is guided so that the direction of the force generated by its own weight is a linear direction by the guide frame 16 and is arranged so as to be linearly reciprocable by the compression spring 17. Thereby, the roller 13 can be linearly reciprocated together with the weight 15.

  The frictional force generating means 10 having such a configuration is arranged such that the moving direction of the roller 13 is the moving direction of the carriage 141, that is, the main scanning direction. Normally, the roller 13 is the frictional force transmitting member 153a, 153b. Is being energized. When the force for rotating the roller 13 in the forward direction works from the frictional force transmission members 153a and 153b, the roller 13 rotates in contact with the frictional force transmission members 153a and 153b, while the roller 13 is rotated in the reverse direction. When the force to rotate the roller 13 is applied from the frictional force transmitting members 153a and 153b, the roller 13 does not rotate and applies a predetermined frictional force to the frictional force transmitting members 153a and 153b. With such a configuration, the operation of the frictional force generating means 10 when the ink jet printer 100 is used in a state tilted from the horizontal direction will be described with reference to FIGS.

  FIGS. 8A to 8C are diagrams showing a case where the frictional force generating means 10 and the moving driving force transmission mechanism 150 are installed horizontally and a case where they are installed vertically. As shown in FIG. 8A, one frictional force generating means 10 is provided on each side of the moving driving force transmission mechanism 150. That is, the first frictional force generating means 10A that generates the frictional force only for the forward movement (A direction) and the second frictional force generating means 10B that generates the frictional force only for the backward movement (B direction). Is arranged. According to such a configuration, as shown in FIG. 8A, when the frictional force generating means 10 and the movement driving force transmission mechanism 150 are installed horizontally, the carriage 141 moves in the forward direction (direction A) or returns. When moving (B direction), the self-weight component of the carriage 141 is not added to the moving direction, and the first frictional force generating means 10A or the second frictional force generating means 10B has the same friction only by the urging force of the compression spring 17. Since the force is generated in the movement driving force transmission mechanism 150, stable movement control of the carriage 141 can be performed.

  On the other hand, as shown in FIG. 8B, when the frictional force generating means 10 and the moving driving force transmission mechanism 150 are installed vertically with the B side facing downward, the carriage 141 faces downward, that is, the backward movement (B direction) ), The second frictional force generating means 10B causes the moving driving force transmission mechanism 150 to generate a biasing force of the compression spring 17 and a frictional force due to its own weight such as the weight 15. When the carriage 141 moves upward, that is, in the outward movement (direction A), the first frictional force generating means 10A moves due to its own weight such as the weight 15 acting in the opposite direction to the urging force of the compression spring 17. It hardly occurs in the driving force transmission mechanism 150. For this reason, the frictional force of the second frictional force generating means 10B cancels the movement component of its own weight during the backward movement (B direction) of the carriage 141, and the movement direction of its own weight during the forward movement (A direction). Since the components can be the same, stable movement control of the carriage 141 can be performed.

  Further, as shown in FIG. 8C, when the frictional force generating means 10 and the movement driving force transmission mechanism 150 are installed vertically with the A side facing downward, the carriage 141 faces downward, that is, the forward movement (direction A). ), The first frictional force generating means 10 </ b> A causes the driving force transmission mechanism 150 to generate the urging force of the compression spring 17 and the frictional force due to its own weight such as the weight 15. When the carriage 141 moves upward, that is, when the carriage moves in the backward direction (B direction), the second frictional force generating means 10B moves due to its own weight such as the weight 15 acting in the opposite direction to the urging force of the compression spring 17. It hardly occurs in the driving force transmission mechanism 150. For this reason, the frictional force of the first frictional force generating means 10A cancels the movement component of its own weight when the carriage 141 moves forward (A direction), and the movement direction of its own weight when returning (B direction). Since the components can be the same, stable movement control of the carriage 141 can be performed.

  FIG. 9 shows the load due to the weight of the carriage 141 when the frictional force generating means 10 and the moving driving force transmission mechanism 150 are installed at a predetermined angle θ, with 0 ° in the vertical state and 180 ° in the vertical state and 90 ° in the horizontal state. It is a figure which shows the change of P (it makes positive the direction which opposes a moving direction). As apparent from FIG. 9, when the carriage 141 moves in the forward direction (A direction), the carriage load P increases as the angle θ increases, and when the carriage 141 moves in the backward direction (B direction), the carriage increases as the angle θ increases. The load P is reduced. That is, the greater the inclination of the ink jet printer 100, the greater the difference in carriage load P depending on the movement direction of the carriage 141. Therefore, in order to cause the frictional force generating means 10 to generate a frictional force that cancels the carriage load P, the pressing force R of the pressing force control means 12, that is, the spring force of the compression spring 17 and the mass of the weight 15 are set.

  FIGS. 10A and 10B are diagrams illustrating the relationship between the angle θ and the pressing force R. FIG. FIG. 10A shows a case where the pressing force R is set so that the angle 13 is 90 ° (horizontal) and the roller 13 is in sliding contact with and disengaged from the frictional force transmission members 153a and 153b. This is a case where the roller 13 is set to press the frictional force transmitting members 153a and 153b with a predetermined pressing force R even when the angle θ is 90 ° (horizontal). The frictional force N is the pressing force R × the friction coefficient ν. In this example, when the pressing force R is 10, the frictional force N is 30. That is, the friction coefficient ν is 3. The total load PP of the carriage 141 (the direction opposite to the moving direction is positive) PP is the sum of the carriage load P and the frictional force N.

  11A and 11B are diagrams showing the relationship between the angle θ and the total carriage load PP. FIG. 11A is a diagram corresponding to FIG. 10A. When the angle is 90 ° (horizontal), the carriage total load PP does not occur, but when the inclination of the ink jet printer 100 increases, the forward movement There is some difference between the carriage total load PP in the (A direction) and the carriage total load PP in the backward movement (B direction). FIG. 11B is a diagram corresponding to FIG. 10B. Although there is a loss, it can be stabilized at a constant total carriage load PP (30) with a total inclination, and stable movement control of the carriage 141 is performed. It can be performed.

  FIG. 12 is a diagram showing another example of the moving driving force transmission mechanism 150 and the frictional force generating means 10. The moving driving force transmission mechanism 150 includes lead screws 154 instead of the pulleys 151 a and 151 b and the carriage belt 152. Further, the frictional force generating means 10 has the same weight 15, guide frame 16 and compression spring 17, but includes a disk 18 and a shaft member 19 instead of the roller 13 and the support member 14. Even in such a configuration, the disk 18 is normally urged by the frictional force transmission members 155a and 155b, and a force to rotate the disk 18 in the forward direction works from the frictional force transmission members 155a and 155b. The disk 18 rotates in contact with the frictional force transmitting members 155a and 155b. On the other hand, when the force to rotate the disk 18 in the reverse direction is applied from the frictional force transmitting members 155a and 155b, the disk 18 is not rotated. A predetermined frictional force is applied to the frictional force transmitting members 155a and 155b. Accordingly, the above-described operational effects are exhibited.

  Although the above-described frictional force generating means 10 is self-controlling, the inclination of the frictional force generating means 10 and the moving driving force transmission mechanism 150 is detected, and the pressing force R is changed by combining the actuator and the control system. You may comprise as follows. The inclination of the frictional force generating means 10 and the moving driving force transmission mechanism 150 can be detected by, for example, an acceleration sensor or a bottom switch attached to a plurality of installation surfaces (as discontinuous points). The pressing force R in such a case may be controlled based on a graph obtained by inverting FIG. Further, a damper or a plunger may be used as the pressing force control means 12.

  In the recording unit 140, a linear encoder scale 147 for detecting the movement position of the carriage 141 is disposed below the carriage 141 and between the carriage guide shaft 144 and the paper feed roller 123a. A linear encoder 148 that reads magnetic information of the linear encoder scale 147 is attached to the lower surface of the carriage 141. Since the carriage 141 is disposed across the paper feed roller 123a, a dead space is formed below the carriage 141 and between the carriage guide shaft 144 and the paper feed roller 123a. By adopting the arrangement as described above, dead space can be eliminated. According to the carriage motor 146 and the movement driving force transmission mechanism 150 as described above, the carriage 141 connected to the carriage belt 152 is driven and controlled based on the detection signal from the linear encoder 148, so that the recording mounted on the carriage 141 is performed. The head 142 can be reciprocated with high accuracy.

  As shown in FIGS. 2, 3, and 5, the cartridge storage unit 160 has a function of storing a black ink cartridge 161 and a color ink cartridge 162 and supplying each color ink to the recording head 142. The following members are disposed between the movable paper guide upper 121 a and the movable paper guide lower 121 b and the back surface of the lower case 111. That is, the cartridge holders 163 and 164 for holding the ink cartridges 161 and 162 detachably, and the valve mechanism 165 for adjusting the air pressure in the ink cartridges 161 and 162 are provided.

  As shown in FIG. 5, the ink cartridges 161 and 162 are formed in a bag shape of a flexible material, for example, in an outer case 161a, 162a formed of a hard plastic material in a rectangular parallelepiped shape. Ink tanks 161b and 162b filled with inks of various colors such as yellow, light cyan, cyan, light magenta and magenta are sealed. The ink tanks 161b and 162b store the inks of the respective colors to be sent to the recording head 142 via the ink tube 145. However, since the ink tube 145 of the present embodiment is relatively thin and has a large flow path resistance, the pump mechanism 200 is used. It is designed to be pressurized by the air introduced from.

  Ink supply ports 161c and 162c are formed in the center of the front surface of the exterior cases 161a and 162a. The ink supply ports 161c and 162c are connected to the internal ink tanks 161b and 162b through ink holes. The rods 161d and 162d have a substantially cross-shaped cross section. Even when the ink in the ink tanks 161b and 162b flows out and the ink tanks 161b and 162b are crushed, the film of the ink tanks 161b and 162b and the rod 161d are used. , 162d, a flow path is secured to secure an ink outflow path. Then, rubber valves 161e and 162e are fitted into the ink supply ports 161c and 162c via compression springs 161f and 162f. The rubber valves 161e and 162e are formed in a disk shape with, for example, a thermoplastic elastomer.

  As shown in FIG. 5, the cartridge holders 163 and 164 are arranged so that the ink supply needles 163a and 164a for opening and closing the ink supply ports 161c and 162c of the ink cartridges 161 and 162 face the back side of the lower case 111. Has been. As a result, the ink supply needles 163a and 164a of the cartridge holders 163 and 164 can be inserted into the ink supply ports 161c and 162c of the ink cartridges 161 and 162 only by inserting and removing the ink cartridges 161 and 162 with respect to the cartridge holders 163 and 164. Can be put in and out.

  This insertion and removal will be described in more detail. When the ink cartridges 161 and 162 are inserted into the cartridge holders 163 and 164, the ink supply needles 163a and 164a come into contact with the rubber valves 161e and 162e, and the rubber valves 161e and 162e are connected to the ink supply ports 161c and 162c. Push it into the back. As a result, the supply ports perforated on the side surfaces of the rods 161d and 162d are opened, and the ink in each color in the ink tanks 161b and 162b is supplied to the corresponding ink tubes 145 for each color via the ink supply needles 163a and 164a. Can flow into.

  On the other hand, when the ink cartridges 161 and 162 are pulled out from the cartridge holders 163 and 164, the ink supply needles 163a and 164a are detached from the rubber valves 161e and 162e, and the rubber valves 161e and 162e are moved to the ink supply ports 161c and 162c by the action of the compression springs 161f and 162f. It is pushed out to the near side. As a result, the supply ports drilled in the side surfaces of the rods 161d and 162d are closed by the rubber valves 161e and 162e, and the outflow of ink for each color in the ink tanks 161b and 162b can be stopped.

  Since the ink cartridges 161 and 162, the paper feed motor 127, and the carriage motor 146 held by the cartridge holders 163 and 164 are disposed on substantially the same plane, the ink jet printer 100 can be thinned. The cartridge holders 163 and 164 are disposed on the pivot axis side of the paper holder 117, and an ink jet type that effectively utilizes a dead space generated below the paper holder 117 by holding the ink cartridges 161 and 162 therein. In addition to making the printer 100 thinner, the entire inkjet printer 100 can be reduced in size.

  The valve mechanism 165 has a function of adjusting the air pressure applied to the ink tanks 161b and 162b. A check valve (check valve) that maintains the air pressure at a predetermined pressure, the air pressure increases from the predetermined pressure. And a relief valve (pressure control valve) for preventing the leakage and a solenoid valve arranged in parallel with the relief valve. When the ink cartridges 161 and 162 are pulled out from the cartridge holders 163 and 164 in a state where the ink tanks 161b and 162b are pressurized, the ink in the ink tube 145 that has been similarly pressurized flows backward and the ink supply needles 163a and 164a. Comes out. In view of this, a solenoid valve is provided in order to prevent the above-mentioned blowout by letting the air in the ink cartridges 161 and 162 to the outside.

  As shown in FIGS. 2 to 4, the drive control unit 170 has a function of controlling each drive of the paper feed motor 127, the carriage motor 146, the pump motor, the valve mechanism 165, and the recording head 142. The following members are arranged from the left rear side to the movable paper guide 121a. That is, a board case 171 containing a board on which various electronic components (not shown) are mounted, a flexible flat cable (FFC) 172 that transmits a control signal from the board, and a flexible printed cable (FPC) 173 are arranged. Since the ink cartridges 161 and 162 held on the substrate and the cartridge holders 163 and 164 are disposed on substantially the same plane, the ink jet printer 100 can be thinned.

  On the back side of the lower case 111 on the substrate, connectors capable of wiring various cables, for example, a power connector, a USB port, a parallel (RS232C) port, and the like are disposed. The FFC 172 electrically connects a board connector and each connector such as a paper feed motor 127, a carriage motor 146, a pump motor, and a valve mechanism 165, and transmits a control signal from the board. The FPC 173 electrically connects the connector of the substrate and the connector of the recording head 142, and transmits a control signal from the substrate. The FPC 173 is arranged in a substantially U shape on the upper surface of the movable paper guide 121a so as not to interfere with the carriage 141 and the like when the carriage 141 moves, and to bend or cross. The movable paper guide 121a has a rear end portion bent in a substantially L shape, and the bent portion 121aa dams the FPC 173 so that it does not jump out behind the movable paper guide 121a when the carriage 141 moves. Has a function to stop.

  As shown in FIG. 6, the head ejection characteristic recovery unit 180 has a function of keeping the ink ejection of the recording head 142 in a good state, and is hung from the front side on the right side of the lower case 111 to the back side. The following members are arranged. That is, a cap 181 that covers the nozzle surface of the recording head 142, a wiper 182 that wipes the nozzle surface of the recording head 142, an up-and-down mechanism 190 that moves the cap 181 and the wiper 182 up and down, and waste ink and air from the cap 181 shown in FIGS. A pump mechanism 200 for sucking the air is disposed.

  In the ink jet printer 100 configured as described above, an operation when recording on a sheet will be described. It is assumed that the connection wiring and the connection of the power plug between the ink jet printer 100 and the computer have already been completed. First, the user puts his / her finger on the front end of the paper holder 117 in the state shown in FIG. 1A, lifts the paper holder 117 and turns it back to the state shown in FIG. At this time, following the turning of the paper holder 117, the movable paper guide upper 121a and the movable paper guide lower 121b rotate, and the paper supply door 116 rotates to open the paper supply opening 115.

  Subsequently, the user inserts the leading end side of the sheet from the sheet feeding port 115 and inserts the sheet until the leading end of the sheet comes into contact with the contact portion between the sheet feeding roller 123a and the driven roller 123b. As a result, the rear end side of the paper is held along the paper holder 117, so that the paper is set in a state of being inclined forward. Then, the inkjet printer 100 is set in a standby state, and a recording command is input from a computer or the like.

  Then, the paper is nipped between the paper feed roller 123a and the driven roller 123b while being guided by the movable paper guide upper 121a and the movable paper guide lower 121b, the fixed paper guide upper 122a and the fixed paper guide lower 122b, and is sub-scanned. It is sent out in the forward direction. When the sheet reaches the recording stage 143, the carriage 141 starts to move in the main scanning direction. In other words, the carriage 141 positioned at the home position reciprocates between both ends of the sheet that is transported away from the home position.

  At this time, the recording head 142 varies the pressure in the pressure generation chamber by, for example, a piezoelectric element with respect to the sheet being conveyed in the sub-scanning direction, and discharges ink stored in the pressure generation chamber from the nozzle, thereby Predetermined characters and images are recorded on the top. The scanning timing and ink ejection timing of the recording head 142 at this time are controlled by the substrate of the drive control unit 170, and highly accurate ink dot control, halftone processing, and the like are executed. Then, the paper is sandwiched between the paper discharge star wheel 124a and the paper discharge roller 124b and further forwarded, and finally the paper on which recording has been completed is discharged from the paper discharge port 113 to the outside.

  According to the ink jet printer 100 described above, the movable paper guide upper 121a and the movable paper guide lower 121b are configured such that the paper insertion port side is movable up and down, so the movable paper guide upper 121a and the movable paper guide lower 121b. Can be stored in the housing 110 when not in use, and the height dimension of the ink jet printer 100 can be reduced. The movable paper guide upper 121a and the movable paper guide lower 121b are configured to be movable by the link mechanism 210 or to be movable by the torsion coil spring 216. Therefore, the movable paper guide upper 121a and the movable paper guide lower 121b are configured to be movable. Can be moved up and down mechanically, and the reliability of the operation can be improved.

  Further, the movable paper guide upper 121a and the movable paper guide lower 121b move up and down in conjunction with the opening and closing operation of the paper holder 117, so that the user does not have to bother to move the movable paper guide upper 121a and the movable paper guide lower 121b up and down. By simply opening and closing the paper holder 117, the ink jet printer 100 can be put into a use start state or a use end state, and the time required for recording work can be shortened. In addition, since the attachment / detachment of the ink cartridges 161 and 162 is controlled by opening and closing the paper holder 117, it is possible to prevent the ink cartridges 161 and 162 from being inadvertently pulled out during recording, and to cause a defective recording operation. Can be eliminated. Further, since the paper conveyance path from the movable paper guide upper 121a and the movable paper guide lower 121b to the paper discharge outlet 113 through the recording stage 143 is formed in a substantially U shape, the paper is caused to follow the recording stage 143. In addition, the distance between the paper and the recording head 142 can be stabilized and high recording accuracy can be maintained.

  As described above, according to the ink jet printer 100 of the present embodiment, a friction force that can be changed is generated for the moving driving force transmission mechanism 150 that transmits a driving force to the carriage 141, and the generated friction force is generated according to the apparatus posture. Since the frictional force generating means 10 for changing the force is provided, the change in the movement load of the carriage 141 due to the apparatus posture can be canceled by the frictional force, and an extra inertial load as in the case of using a conventional counterweight is added. The moving speed of the carriage 141 can always be constant.

  As long as the printing apparatus includes at least a carriage driving device, the printing apparatus can be applied to a printing apparatus such as a facsimile machine or a copying machine.

1 is a perspective view of an external configuration of an ink jet printer that is one of recording apparatuses according to an embodiment of the present invention when viewed from the front side. It is a perspective view which shows the internal structure of the ink jet type printer of FIG. FIG. 3 is a plan view of FIG. 2. FIG. 4 is a sectional view taken along line AA in FIG. 3. FIG. 4 is a left side view of FIG. 3. FIG. 3 is a perspective view showing a more detailed internal structure on the right front side of the ink jet printer of FIG. 2. It is the top view and top view which show the detail of a frictional force generation means. It is a figure which shows the case where a frictional force generation means and a moving drive force transmission mechanism are installed horizontally, and when installed vertically. It is a figure which shows the change of the load by the dead weight of a carriage at the time of installing a frictional force generation means and a moving drive force transmission mechanism at a predetermined angle. It is a figure which shows the relationship between the angle of FIG. 9, and pressing force. FIG. 10 is a diagram showing the relationship between the angle of FIG. 9 and the total carriage load. It is a figure which shows another example of a movement drive force transmission mechanism and a frictional force generation means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Friction force generation means, 11 Sliding contact means, 12 Pressure control means, 13 Roller, 14 Support member, 15 Weight, 16 Guide frame, 17 Compression spring, 18 Disk, 19 Shaft member, 100 Inkjet printer, 101, 101a Frame, 110 housing, 111 lower case, 112 upper case, 113 paper discharge port, 114 insertion / extraction port, 115 paper supply port, 116 paper supply door, 117 paper holder, 120 paper supply unit and paper discharge unit, 121a movable paper guide Top, 121b Under movable paper guide, 122a Under fixed paper guide, 122b Under fixed paper guide, 123a Paper feed roller, 123b Driven roller, 124a Paper discharge star wheel, 124b Paper discharge roller, 125 Driven roller cradle, 126 Paper discharge star Wheel cradle, 127 paper feed motor, 130 transport driving force transmission mechanism, 140 recording unit, 141 Carriage, 142 Recording head, 143 Recording stage, 144 Carriage guide shaft, 145 Ink tube, 146 Carriage motor, 147 Linear encoder scale, 148 Linear encoder, 150 Moving drive force transmission mechanism, 151a, 151b Pulley, 152 Carriage belt, 153a , 153b, 155a, 155b Friction force transmission member, 154 Lead screw, 160 Cartridge storage part, 161, 162 Ink cartridge, 170 Drive control part, 171 Substrate case, 172 FFC, 173 FPC, 180 Head ejection characteristic recovery part, 181 Cap , 182 Wiper, 190 Vertical mechanism

Claims (12)

A carriage driving device for reciprocating a carriage,
Driving force transmitting means for transmitting a driving force to the carriage;
A friction force generating means for generating a variable friction force in the driving force transmitting means,
The carriage driving device characterized in that the frictional force generating means changes the generated frictional force according to the posture of the device. The frictional force generating means includes a first mechanism that generates a frictional force only for forward movement and a second mechanism that generates a frictional force only for backward movement. The carriage drive device according to 1. 3. The carriage driving device according to claim 1, wherein the generated friction force changes based on a moving direction component of its own weight of the carriage. 4. 4. The carriage driving apparatus according to claim 3, wherein the generated frictional force changes so as to cancel the self-weight component in conjunction with a change in a moving direction component of the self-weight of the carriage. The carriage driving device according to claim 4, wherein the gradient of the change in the generated frictional force is equal to the gradient of the change in the moving direction component of the weight of the carriage. The frictional force generating means includes sliding contact means for generating a frictional force with respect to movement in one direction, and pressing force control means for controlling the pressing force by pressing the sliding contact means against the driving force transmitting means. The carriage driving device according to claim 1, further comprising: a carriage driving device according to claim 1. The sliding contact means is a member that can rotate only in the forward direction, and when a force to rotate in the reverse direction acts from the driving force transmission means, a predetermined friction force is applied to the driving force transmission means. 7. The carriage driving device according to claim 6, further comprising a contact surface provided to the carriage driving device. The pressing force control means includes a weight member connected to the sliding contact means, a defining member for defining a direction of a force generated by the weight of the weight member, and biasing the sliding contact means to the driving force transmitting means. The carriage driving device according to claim 6, further comprising: an urging member that performs biasing. The carriage driving device according to any one of claims 6 to 8, wherein the sliding contact means is disposed so as to be capable of sliding contact with a frictional force transmitting member provided on a pulley. The carriage driving device according to any one of claims 6 to 8, wherein the sliding contact means is disposed so as to be slidable with a frictional force transmission member provided on a lead screw. The carriage driving device according to any one of claims 6 to 10, wherein the pressing force control unit controls the pressing force based on a detection result of a sensor that detects an apparatus posture. A recording apparatus for recording on a recording medium by a recording head mounted on a carriage,
A recording apparatus comprising the carriage driving device according to claim 1.

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