JP5305001B2 - Belt skew correction device, belt conveyance device, and recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt skew correction device capable of performing appropriate skew correction that is appropriate for each state when the belt is in a state of a high skew speed or in a state of a low skew speed. <P>SOLUTION: The belt skew correction device comprises a belt skew correction roller 7 for correcting the screw of an endless belt when it is abutted on a surface of an endless belt 8 wound between a drive roller and a driven roller, and a tilting mechanism 29 for tilting the belt skew correction roller in the direction for correcting the skew of the endless belt. The tilting mechanism comprises a driving body 33 to be intermittently driven by the unit driving amount, and a conversion mechanism 19 for converting the drive of the driving body into the tiltation of the belt skew correction roller with the relationship that the tiltation of the belt skew correction roller 7 is determined corresponding to the driving amount of the driving body. The conversion mechanism 19 is constituted by the correlation that the degree of the change in the corresponding tiltation has a small area and a large area when the driving body performs the intermittent drive with the unit driving amount. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention includes a belt skew correction roller that corrects skew of the endless belt by contacting a surface of an endless belt wound between a driving roller and a driven roller, and the belt skew correction roller. The present invention relates to a belt skew correction device including a tilting mechanism that tilts an endless belt in a correction direction, a belt transport device including the belt skew correction device, and a recording device including the belt transport device. Here, the “recording apparatus” is a concept including a printer (line printer, serial printer, etc.), a facsimile, a copying machine, and the like.

  Hereinafter, a copying machine which is an example of a recording apparatus will be described as an example. As shown in Patent Document 1 or 2 below, a belt conveying apparatus is often used as a recording material conveying means in a copying machine. A problem in the belt conveying device is the skew of the endless belt wound between the driving roller and the driven roller. When the endless belt is skewed, the recording material held and transported by the endless belt is tilted, and the image recorded on the recording material is also disturbed or tilted. Further, if the endless belt is left skewed, the edge of the endless belt is damaged, which causes a decrease in conveying force, disturbance of conveyance, or stop of conveyance.

Therefore, as shown in Patent Document 1 or 2 below, a belt skew feeding correction device is generally mounted on the belt conveyance device, and the occurrence of the above-described problems caused by the skew feeding of the endless belt is reduced.
Japanese Patent No. 3082452 JP 2002-251080 A

  In the conventional belt skew correction device, a cam mechanism is used as a tilt mechanism for tilting the belt skew correction roller. The cam constituting the cam mechanism is rotationally driven integrally with a rotary drive body using a motor or the like as a drive source. The tilting amount of the belt skew feeding correction roller is a fixed proportional relationship (linearly proportional to the rotational drive amount of the cam. (Correlation).

  However, since the rotation amount of the cam and the tilting amount of the belt skew correction roller are configured in a certain proportional relationship as described above, the belt is in a state where the skew speed is high (hereinafter referred to as “highly unstable state”). )), The skew correction cannot be executed quickly, and the belt is slightly deviated from the stable state (hereinafter also referred to as “small instability state”). There was a problem that fine skew correction could not be executed at a certain time. If the gradient of the proportional relationship is increased, it becomes easy to execute a quick skew correction for the large unstable state, but this makes it possible to execute a fine skew correction for the small unstable state. In other words, it is impossible to execute an appropriate skew correction for each state. On the contrary, when the gradient is small, it is easy to execute a fine skew correction for the small unstable state, but a quick skew correction can be executed for the large unstable state. Can not.

  This problem becomes even more prominent when a configuration is employed in which a drive body for rotationally driving the cam is intermittently driven for each unit drive amount in order to simplify the cam rotational drive control.

  The object of the present invention is to execute both a fine control and a quick control for belt skew correction in a series of skew correction operations, so that the belt is in a state where the skew speed is high (large instability). State), or when the skew speed is slightly deviated slightly from the stable state (small instability state), and appropriate skew correction suitable for each state of the belt is executed. An object of the present invention is to provide a belt skew feeding correction device, a belt transport device including the belt skew correction device, and a recording device including the belt transport device.

  In order to solve the above-described problem, the belt skew feeding correction device according to the first aspect of the present invention is configured to contact the surface of the endless belt wound between the driving roller and the driven roller. A belt skew correction roller that corrects the skew and a tilt mechanism that tilts the belt skew correction roller in a direction that corrects the skew of the endless belt. The tilt mechanism is driven intermittently by a unit drive amount. And a conversion mechanism for converting the driving of the driving body into the tilting of the belt skew correction roller with a relationship in which the tilting amount of the belt skew correction roller is determined corresponding to the driving amount of the driving body. And the conversion mechanism has a relationship between the drive amount and the tilt amount that is large when the drive body advances the drive intermittently with a unit drive amount and the degree of change of the corresponding tilt amount is small and large. Correlation with regions And it is characterized in that it is configured with the engaging.

  According to this aspect, the relationship between the driving amount of the driving body and the tilting amount of the skew feeding correction roller corresponds to the change in the tilting amount when the driving body advances the driving intermittently by the unit driving amount. It has a correlation with a small area and a large area. Accordingly, both the quick control and the fine control for belt skew correction can be executed in a series of skew correction operations only by intermittently driving the drive body with a unit drive amount. Accordingly, when the belt is in a state where the skew speed is high (largely unstable state), or when the belt is in a state where the skew speed is slightly shifted from the stable state (smallly unstable state), the belt Appropriate skew correction suitable for each state can be executed.

  According to a second aspect of the present invention, in the belt skew correction device according to the first aspect, the correlation is a region where the degree of change in the tilt amount is small near the center of the driving range of the driving body. In the vicinity of both ends of the drive range, the degree of change is a large region, and the two regions are continuously connected.

  According to this aspect, when the belt returns from the largely unstable state to the stable state, the quick skew correction is executed at first, and gradually changes to the gentle skew correction as the skew speed becomes gentle. Since the finest skew correction is performed, the belt can be easily returned to the stable position.

In addition, when the belt in a stable state becomes a small unstable state for some reason, the driving body is intermittently driven by a unit driving amount (usually about 1 unit to 3 units). Since the inclination of the skew correction roller changes finely from the initial position, the inclination correction roller can take a state of inclination (small inclination) suitable for the skew correction for the small instability state. In other words, skew correction is performed with an appropriate inclination that does not become excessive. Therefore, the belt is smoothly returned from the small unstable state to the stable state.
On the other hand, when the belt suddenly changes from a stable state to a large unstable state for some reason, the inclination of the skew feeding correction roller gradually increases as the driving body advances the driving intermittently by a unit driving amount. Go. At this time, the change in the inclination of the skew feeding correction roller is small at first, but if the area is exceeded, the change in the inclination per unit driving amount becomes large. Accordingly, in order to appropriately execute the skew correction for the small instability state, the skew correction per unit driving amount of the driving body is further provided while a region for finely changing the inclination of the skew correction roller is provided. By providing a region where the change in the inclination of the roller becomes large, the total time required for the skew correction roller to take a state of a large inclination suitable for the skew correction for the large unstable state can be shortened. Is possible.

  According to a third aspect of the present invention, in the belt skew feeding correction device according to the second aspect, the drive body is a rotary drive body, the conversion mechanism includes a cam mechanism, and the cam constituting the cam mechanism includes The cam follower rotates integrally with the rotary driving body and is positioned on the belt skew feeding correction roller side, and the correlation is constituted by a relative shape of the cam and the cam follower. is there.

  According to this aspect, since the correlation between the driving amount of the driving body and the tilting amount of the skew feeding correction roller is defined by the relative shape of the cam and the cam follower, the structure is simplified and the second aspect The effect of this can be obtained.

  According to a fourth aspect of the present invention, there is provided the belt skew feeding correction device according to any one of the first to third aspects, wherein the belt skew feeding correction roller has a roller diameter at a central portion with respect to both ends. It is a roller with a different diameter that increases.

  According to this aspect, in addition to the operational effects of any one of the first to third aspects, the following operational effects are obtained. That is, since the belt skew correction roller is a different diameter roller, the endless belt is less likely to slip with respect to the belt skew correction roller, and the belt skew correction roller tries to correct the skew transmitted to the endless belt. The transmission efficiency of the power to be improved. Further, since the endless belt itself generates a force to approach the center, the occurrence of skewing of the endless belt can be suppressed, and the endless belt can be prevented from wrinkling.

  According to a fifth aspect of the present invention, in the belt skew feeding correction device according to any one of the first to fourth aspects, ON and OFF for detecting each edge position in the belt width direction of the endless belt. A switch-type edge sensor, and a control device that drives the drive body by the unit drive amount to execute skew correction control of the endless belt when any one of the edge sensors detects an ON state. And the control device determines whether or not the ON state of the edge sensor is released after a set waiting time has elapsed after driving the driving body by the unit driving amount, and the ON state is released. If not, the driving body is further driven by the unit driving amount, and after the set waiting time has elapsed, the determination as to whether the ON state of the edge sensor has been released is performed again. And it is characterized in that it is configured to repeat for each of the set waiting time within limits set in advance the same operation.

According to this aspect, when any one of the edge sensors detects the ON state, the skew driving correction control is performed on the endless belt by driving the driving body by the unit driving amount, and then When the set waiting time has elapsed, it is determined whether or not the ON state of the edge sensor has been released. If the ON state has not been released, the drive body is further driven by the unit drive amount, and then When the set waiting time elapses, it is determined again whether or not the ON state of the edge sensor is released, and the same operation is repeated for each set waiting time within a preset limit. .
Therefore, the skew correction of the belt is automatically executed with a simple structure. Furthermore, since an edge sensor of an ON / OFF switch type that is relatively simple and inexpensive is used as the edge sensor, the number of parts and the part cost can be reduced.

  The sixth aspect of the present invention is characterized in that the waiting time is set corresponding to a value of a driving amount when the driving body is driven by the unit driving amount.

  According to this aspect, by setting the waiting time corresponding to the value of the driving amount when the driving body is driven by the unit driving amount (setting waiting time), the skew of the belt is prevented, and further It is possible to suppress excessive control of the belt skew prevention control.

For example, by setting a short waiting time when the belt is in the small instability state, it is possible to check the state of the belt in detail and prevent the belt from skewing.
On the contrary, by setting a long waiting time when the belt is in the state of great instability, it is possible to suppress overshooting of the control for preventing the skew of the belt.

  According to a seventh aspect of the present invention, there is provided a belt conveyance device according to a seventh aspect of the present invention, wherein a drive roller that imparts conveyance force to an endless belt and a driven roller that is disposed opposite to the drive roller and holds the endless belt in tension with the drive roller. A belt skewer including a roller, an endless belt wound between the driving roller and the driven roller, and a belt skew correction roller that corrects the skew of the endless belt by abutting against a surface of the endless belt. A belt correction device, wherein the belt skew correction device is any one of the first to sixth belt skew correction devices.

  According to this aspect, in various belt conveyance devices including an endless belt, the same operational effects as any one of the belt skew correction devices according to the first to sixth aspects can be obtained. . And the conveyance of a to-be-conveyed object becomes smooth, and a belt conveying apparatus can be operated stably over a long time.

  According to an eighth aspect of the present invention, there is provided a recording apparatus for holding and conveying a recording material, and a recording execution for executing recording on the recording material held and conveyed by the belt conveying apparatus. And the belt conveyance device is the belt conveyance device according to the seventh aspect.

  According to this aspect, in the recording apparatus such as an ink jet printer that applies the belt conveying apparatus as the conveying means for the recording material, the same effects as the belt conveying apparatus according to the seventh aspect can be obtained. . As a result, the recording material can be smoothly conveyed and the recording quality can be improved.

  Hereinafter, a belt skew correction device according to the present invention, a belt transport device including the belt skew correction device, and a recording device including the belt transport device will be described. First, as the best mode for carrying out the recording apparatus of the present invention, an inkjet printer 100 equipped with a belt conveyance device as a conveyance means for a recording material (hereinafter also referred to as paper) P is taken up, and an outline of the overall configuration is taken. This will be described with reference to the drawings.

  FIG. 1 is a side sectional view schematically showing an outline of the internal structure of an ink jet printer provided with a belt conveying device to which a belt skew correcting device of the present invention is applied, and FIG. 2 is an application of the belt skew correcting device of the present invention. It is a top view which shows the outline of a belt conveying apparatus. FIG. 3 is a plan view schematically showing each state of the endless belt during normal time (a), left side skew (b), and right side skew (c).

  The ink jet printer 100 includes a printer main body (not shown) which is an example of a recording apparatus main body. The ink jet printer 100 holds and transports paper P inside the printer main body, and the paper held and transported by the transport means 2. A recording execution unit 3 that performs recording on P is provided. In the inkjet printer 100 shown in the drawing, the conveyor means 2 is applied with the belt conveyor 20, and the paper P fed by a feeding means (not shown) passes through the gate roller 4 constituted by a pair of nip rollers. It is supplied onto the belt conveying device 20.

  The belt conveying device 20 includes a driven roller 5 on the upstream side in the conveying direction A, a driving roller 6 on the downstream side in the conveying direction A, and a belt skew according to the present invention described below below a position between the driven roller 5 and the driving roller 6. A belt skew feeding correction roller 7 which is a constituent member of the row correction device 1 is arranged, and an endless belt 8 is wound around these three rollers 5, 6 and 7 in a loop shape.

  The driven roller 5 and the drive roller 6 are straight tube or round bar-like members, and are the same diameter rollers that are uniform in the axial direction B. Of these, the driving roller 6 is a roller that applies a conveying force in the conveying direction A to the endless belt 8, and a conveying driving motor 9 that transmits power to the driving roller 6 is directly connected to one end in the axial direction B as an example. Has been. On the other hand, the driven roller 5 is a roller having the same height as the driving roller 6 and arranged in parallel and facing a predetermined distance. Between the driving roller 6 and the driven roller 5, a conveyance surface 10 for the paper P is formed, which is formed by stretching the endless belt 8 horizontally in a tension state.

  The endless belt 8 is an endless belt-shaped member formed of an elastic material such as synthetic rubber. As shown in the figure, the endless belt 8 has a large number of holes 11, 11,..., Through which the sheet P is sucked and held by a suction device (not shown). The paper P is sucked and held on the transport surface 10. In addition, as an adsorption method of the adsorption device, suction by negative pressure or electrostatic adsorption can be adopted as an example. The recording execution unit 3 includes a recording head 13 that performs recording by discharging ink of each color onto the upper surface of the paper P as a main constituent member.

[Example 1]
Next, the belt skew feeding correcting device 1 of the present invention applied to the belt conveying device 20 mounted on the ink jet printer 100 configured as described above will be specifically described with reference to the drawings.

  FIG. 4 is a side sectional view showing a tilting mechanism in the belt skew correction device of the present invention, and FIG. 5 shows various shapes (a) to (d) of the belt skew correction roller in the belt skew correction device of the present invention. It is a front view. FIG. 6 is a timing chart of the endless belt skew correction control element, and FIG. 7 is a flowchart showing an example of the endless belt skew correction control. FIG. 8 is a front view of a cam constituting the cam mechanism according to the present invention, and FIG. 9 is a diagram showing the relationship between the cam rotation angle (rotation angle of the rotary drive member) and the tilt amount of the belt skew correction roller.

  The belt skew feeding correction device 1 according to this embodiment corrects the skew feeding of the endless belt 8 by coming into contact with the back surface of the endless belt 8 wound between the driving roller 6 and the driven roller 5. A row correction roller 7 is provided. As shown in FIGS. 5A to 5D, the belt skew correction roller 7 is a different-diameter roller whose roller diameter is larger at the center than at both ends. Incidentally, in this embodiment, when the roller diameter at the center is D and the roller diameter at both ends is d, D−d = 0.3 mm, and the roller diameter D at the center is larger than the roller diameter d at both ends. Is also set to be large.

  FIGS. 5A and 5B show belt skew correction rollers 7A and 7B formed so that the roller diameter continuously changes over the entire length. The belt skew feeding correction roller 7A shown in FIG. 5A has small diameter portions 21 and 21 at both ends and a large diameter portion 22 at the central portion, and from the left and right small diameter portions 21 and 21 to the large diameter portion 22 at the central portion. The outer surface is formed as a different diameter roller having a convex curved surface. That is, the belt skew correction roller 7A is formed in a so-called crown shape. On the other hand, the belt skew feeding correction roller 7B shown in FIG. 5B also has small diameter portions 21 and 21 at both ends and a large diameter portion 22 at the central portion, and the central large diameter from the left and right small diameter portions 21 and 21. The roller diameter is linearly increased over the portion 22.

  5 (c) and 5 (d) show belt skew correction rollers 7C and 7D formed so that the roller diameter changes over a partial range in the axial direction. Among them, the belt skew feeding correction roller 7C shown in FIG. 5C is a different diameter roller having a wide range of the large diameter portion 22 in which the corner portions at both ends are chamfered, while shown in FIG. 5D. The belt skew correction roller 7 </ b> C is a different-diameter roller having a wide range of small-diameter portions 21, 21 bulging only the central portion.

  By using the belt skew feeding correction roller 7 having such a shape, the slip of the endless belt 8 with respect to the belt skew feeding correction roller 7 is suppressed, and the belt skew feeding correction roller 7 corrects the skew feeding of the endless belt 8. The force to be transmitted is transmitted to the endless belt 8 with high efficiency. In addition, by using the belt skew correction roller 7 having the above-described shape, a force is generated in the endless belt 8 itself so as to approach the center, and the occurrence of the skew of the endless belt 8 is suppressed. Occurrence is also prevented.

  As shown in FIG. 2, in addition to the belt skew correction roller 7, the belt skew correction device 1 includes left and right edges 23 in the belt width direction (coincidence with the axial direction B) of the endless belt 8. , 24 are provided with two edge sensors, that is, an ON / OFF switch type left edge sensor 25 and a right edge sensor 26 for detecting the respective edge positions. These edge sensors 25 and 26 are both in the OFF state at the normal time shown in FIG. 3B, the left edge sensor 25 is in the ON state, the right edge sensor 26 is in the OFF state, and the right edge sensor 26 is in the ON state in the right skew shown in FIG. 3C. The left edge sensor 25 is set to be in an OFF state. As the edge sensors 25 and 26, non-contact sensors such as an optical sensor including a light emitting unit 27 and a light receiving unit 28 are employed as an example.

  Further, as shown in FIG. 2, the belt skew feeding correction device 1 is provided with a tilting mechanism 29 that tilts the belt skew feeding correction roller 7 in a direction for correcting the skewing of the endless belt 8. The tilt mechanism 29 has a relationship in which the cam operation motor 33 which is a driving body as a power source and the tilt amount of the belt skew correction roller 7 are determined in accordance with the rotational drive amount of the cam drive motor 33. A conversion mechanism 19 that converts the rotational drive of the operation motor 33 into the tilt of the belt skew correction roller is provided. The conversion mechanism 19 includes a roller support frame 30, a cam follower 31 that forms a cam mechanism 39, a tilt cam 32 that also forms a cam mechanism 39, and an urging unit 34.

  The cam operating motor 33, which is the drive body, adopts a configuration in which it is driven intermittently for each unit drive amount in order to simplify the cam rotational drive control. That is, the rotation of the tilting cam 32 is intermittently performed by receiving power from the cam operating motor 33 that is a rotationally driven body that is intermittently driven to rotate at a constant unit driving amount (unit rotational angle). Further, on the rotation shaft 40 of the tilt cam 32, a detection plate 41 in which a large number of slits are formed radially, for example, is provided in order to set the rotation angle of the tilt cam 32. The rotation amount of the detection plate 41 can be detected by a cam position sensor 42 provided in the vicinity. The detection plate 41 and the cam position sensor 42 need not be provided.

  Furthermore, in this embodiment, a swing arm 35 and a tension spring 36 are provided in order to use the belt skew correction roller 7 as a tension roller.

  The roller support frame 30 supports the belt skew feeding correction roller 7 in a rotatable state, and is shown by an arrow G in FIG. 4 around a rotation fulcrum O provided in the upper right part in FIG. This is a support member that rotates at a predetermined angle. A shaft portion 37 is raised at the upper left portion on the rotation free end side of the roller support frame 30, and a small-diameter disk-shaped cam follower 31 is attached to the shaft portion 37 so as to be rotatable. . The cam follower 31 is provided with a tilting cam 32 that transmits driving force to the roller support frame 30 in a constantly contacted state. The tilting cam 32 has a cam surface 38 formed so that the cam height gradually changes as a part of the peripheral surface, and the contact position of the cam surface 38 that contacts the peripheral surface of the cam follower 31. The tilt angle θ of the belt skew correction roller 7 can be adjusted by changing.

  That is, in the belt skew correction device according to this embodiment, the tilt mechanism 29 includes the cam operation motor 33 that is intermittently driven by a unit drive amount, and the rotation drive amount of the cam operation motor 33 corresponding to the cam operation motor 33. A conversion mechanism 19 is provided that converts the drive of the cam operating motor 33 into the tilt of the belt skew correction roller 7 with a relationship that determines the amount of tilt of the belt skew correction roller 7. The conversion mechanism 19 has a relationship between the rotational drive amount of the cam operating motor 33 and the tilt amount of the belt skew feeding correction roller 7 as shown in FIG. When the driving is advanced, the degree of change in the tilt amount of the corresponding belt skew correction roller 7 is correlated with a small region and a large region.

  Further, as shown in FIG. 9, the correlation between the rotational drive amount of the cam operating motor 33 (that is, the rotational angle of the tilt cam 32) and the tilt amount of the belt skew correction roller 7 is the same as that of the tilt cam 32 and the cam follower. 31 and the degree of change in the amount of tilting is small in the vicinity of the center of the rotational drive range of the cam operating motor 33 (that is, the tilting cam 32), and in the vicinity of both ends of the rotational drive range. It is configured such that the degree of change is a large area and the both areas are continuously connected.

The shape of the tilting cam 32 shown in FIG. 8 is an example of the relative shape of the tilting cam 32 and the cam follower 31 for realizing the correlation shown in FIG. The cam follower 31 is formed in a simple cylindrical shape. Further, in this embodiment, the unit driving amount of the cam operating motor 33 is set to 15 ° as a rotation angle. Further, the rotational drive range of the cam operating motor 33 is set to 150 ° as a rotation angle, and is set so that the tilt direction is switched around a position of 75 °. In FIG. 8, the symbol R indicates the rotation range of the tilt cam 32 (range corresponding to 0 ° to 150 ° in FIG. 9).
The 75 ° position corresponds to the stable position of the designed belt. Accordingly, at the time of assembly, the tension balance, the cam fixing position, and the like are adjusted so that the vicinity of the stable position is at the center of the rotation range of the tilt cam 32.

  The urging means 34 is a member that urges the roller support frame 30 so that the cam follower 31 is always in contact with the tilting cam 32, and is constituted by a tension coil spring as an example. One end of the urging means 34 is locked at the lower right portion of the roller support frame 30 in FIG. 4, and the other end of the urging means 34 is locked to an appropriate fixing frame of the printer main body (not shown). .

  A shaft portion 43 is raised at the lower left portion of the roller support frame 30 in FIG. 4, and the swinging arm 35 is in the tension direction indicated by the arrow H in FIG. And it is provided in a state in which it can swing in the relaxation direction. Further, as an example, a tension coil spring is interposed between the base end portion 44 of the swing arm 35 located at the upper left portion in FIG. 4 with the swing support point Q interposed therebetween and the rotation support point O of the roller support frame 30. The above-described tension spring 36 constituted by is stretched.

  Further, the belt skew feeding correction device 1 drives the cam operation motor 33 by a unit drive amount (angle of 15 °) when any one of the edge sensors (for example, 25) detects the ON state. A control device 46 that executes skew correction control of the endless belt 8 is provided.

  The control device 46 determines whether or not the ON state of the edge sensor (25) has been released after the set waiting time has elapsed after the cam operating motor 33 (tilting cam 32) has been rotated by 15 °. If the ON state is not released, the cam operating motor 33 (tilting cam 32) is further rotated by 15 °, and the ON state of the edge sensor (25) is released after the set waiting time has elapsed. It is configured to repeat the determination for each set waiting time until a similar operation is performed within a preset limit, for example, a preset operation duration time elapses.

  Specifically, as shown in FIG. 6, the control device 46 drives the drive pulse X for driving the tilting mechanism 29 and the waiting time Y (until the next drive pulse X is driven. 6) is set, and every time the waiting time Y elapses, the drive pulse X is sent as an operation command to the tilting mechanism 29, and the skew correction operation is executed. Here, the drive amount of the drive pulse X is an amount by which the cam operating motor 33 (tilting cam 32) is rotationally driven by 15 °.

[Description of skew correction operation]
Next, a specific skew correction operation by the control device 46 will be described with reference to FIGS. 3, 7, and 9.
The skew correction control of the endless belt 8 is executed based on the preset drive amount of the drive pulse X (FIG. 6) and the waiting time Y (FIG. 6) until the next drive pulse X is driven. First, the start switch 50 (FIG. 2) is pressed to drive the transport drive motor 9, and the transport operation of the endless belt 8 is started. At the same time, the left and right edges 23 and 24 of the endless belt 8 can be detected by the left and right edge sensors 25 and 26.

  Then, in step S1 in FIG. 7, the ON / OFF state of the left edge sensor 25 is confirmed. When the left edge sensor 25 is in the ON state as shown in FIG. 3B, the process proceeds to step S2 where the cam operating motor 33 (tilting cam 32) is rotated by a unit driving amount of 15 ° to As shown in FIG. 3B, the row correction roller 7 is tilted in a direction (an arrow direction of θ) for correcting the skew of the endless belt 8. The actual tilting amount of the skew feeding correction roller 7 at this time is determined by the relationship shown in FIG. Then, when the process goes to step S3 and the waiting time Y elapses, it is determined whether or not the ON state of the edge sensor 25 is released. If the ON state has not been released, the cam operating motor 33 (tilting cam 32) is further rotated by 15 °, and then the ON state of the edge sensor 25 is released after the set waiting time Y has elapsed. Execute the determination again. The same operation is repeated for each set waiting time until a preset operation continuation time (for example, the time for which the endless belt 8 makes 10 revolutions) elapses.

  On the other hand, when the left edge sensor 25 is in the OFF state, the process proceeds to step S4, and the ON / OFF state of the right edge sensor 26 is confirmed. As shown in FIG. 3C, when the right edge sensor 26 is in the ON state, the process proceeds to step S5 and step S6, and “rotates by 15 ° of unit drive amount” as in step S2 and step S3. And “determination after waiting time Y has elapsed”. The same operation is repeated for each set waiting time until a preset operation duration time elapses.

  If the deviation is not resolved even after a preset operation continuation time has elapsed, a warning is issued, the transport drive motor 9 and the cam operation motor 33 are stopped, and all operations are stopped. It has become. When all the operations are stopped by issuing a warning, the tension of the belt skew feeding correction roller 7 acting on the back surface of the endless belt 8 is released and the deviation of the endless belt 8 is manually eliminated. Then, a reset operation is executed to return the basic control operation.

  That is, according to the present embodiment, the relationship between the drive amount of the cam operation motor 33 (tilt cam 32) and the tilt amount of the skew feeding correction roller 7 indicates that the cam operation motor 33 (tilt cam 32) is in units of 15 °. As shown in FIG. 9, when the rotation is intermittently advanced, the corresponding degree of change in the tilt amount is configured to have a correlation with a small region and a large region. Therefore, by simply driving the cam operating motor 33 (tilting cam 32) intermittently in units of 15 °, quick control (near both ends in FIG. 9) and fine control (center of FIG. 9) are performed. Can be executed in a series of skew correction operations. That is, when the belt 8 is in a state where the skew speed is high (largely unstable state), or when the belt 8 is in a state where the skew speed is slightly deviated slightly from the stable state (smallly unstable state), Appropriate skew correction suitable for each state can be executed.

  Furthermore, according to the present embodiment, when the endless belt 8 returns from the large unstable state to the stable state, as shown in FIG. 9, first, the rapid skew correction is executed, and as the skew speed becomes gentler. Since the gradual skew correction is gradually performed and the finest skew correction is executed at the end, the endless belt 8 can be easily returned to the stable state position.

  Further, when the endless belt 8 that has been in a stable state becomes a small unstable state for some reason, the cam operation motor 33 (tilting cam 32) is intermittently rotated in units of 15 °. Since the inclination of the skew correction roller 7 changes finely from the initial position (for example, the 75 ° position in FIG. 9), the inclination (small inclination) is suitable for the skew correction for the small instability state. Can be taken. In other words, skew correction is performed with an appropriate inclination that does not become excessive. Therefore, the endless belt 8 can smoothly return from the small unstable state to the stable state.

  On the other hand, when the endless belt 8 suddenly changes from a stable state to a large unstable state for some reason, the cam operation motor 33 (tilting cam 32) is driven intermittently in units of 15 °, whereby the skew correction is performed. The inclination of the roller 7 increases step by step. At this time, the change in the inclination of the skew feeding correction roller 7 is initially small (near the center of FIG. 9), but the change in the inclination per unit driving amount (15 °) increases beyond that region (FIG. 9). Near both ends). Accordingly, in order to appropriately execute the skew correction for the small instability state, a unit drive of the cam operation motor 33 (tilting cam 32) is further provided while providing a region for finely changing the inclination of the skew correction roller 7. By providing a region (near both ends in FIG. 9) in which the change in the inclination of the skew correction roller 7 per amount (15 °) is large, a state of a large inclination suitable for the skew correction for the large unstable state can be obtained. The total transition time required for the skew correction roller 7 to be taken can be shortened.

[Example 2]
In the second embodiment, a table in which the cam operation motor 33 (tilting cam 32) is changed for each unit driving amount (unit rotation angle) and a waiting time Y (set waiting time) corresponding to the value is associated with the table. The table is created in advance and stored in the control device 46. Based on the table, the cam operation motor 33 (tilting cam 32) waits according to the value that changes for each unit drive amount (unit rotation angle). In this embodiment, Y is changed.

  FIG. 10 shows an example of a table in which the cam operation motor 33 (tilting cam 32) is associated with a value that changes for each unit drive amount (rotation drive by 5 °) and a waiting time Y corresponding to the value. Yes.

  As for the skew correction operation, when the waiting time Y is set according to the value that the cam operation motor 33 (tilting cam 32) changes for each unit drive amount (unit rotation angle), as shown in FIG. First, the rotation angle of the tilt cam 32 is detected (step S01), and the waiting time corresponding to the rotation angle is set based on the table stored in the control device described above (step S02), and then the process proceeds to step S1. To do. The control operation after step S1 subsequent to step S02 is the same as that described in FIG. 7 in [Description of skew feeding correction operation] of the first embodiment, and thus description thereof is omitted.

  Refer to FIGS. 3, 6, 10, 11 and 12 for the contents of the second embodiment, and control for preventing the skew of the belt in the small unstable state and the belt in the large unstable state The control for preventing the skew will be described separately.

  First, a description will be given of control for returning a belt that is skewed in a small unstable state to a stable state.

  The case where the rotational drive amount of the rotational drive body (hereinafter referred to as “cam rotational angle”) changes from 90 ° to 95 ° in FIG. 11 will be described as an example.

  When the rotation angle of the cam changes from 90 ° to 95 ° in FIG. 11, the change in the tilt amount of the belt skew roller 7 (hereinafter simply referred to as “tilt amount”) is slight (Δ1). That is, the amount of tilting of the belt skew feeding correction roller 7 in FIG. 3B (or (c)) is very small (Δ1). Therefore, since the amount of tilting is small, the force for correcting the skew of the belt is small. For this reason, in the small instability state, the force that the belt tries to skew prevails over the force that tries to correct the belt skew. The difference between the two forces tends to increase in a small instability state where the amount of tilting is small.

  Therefore, by setting the waiting time Y in FIG. 6 to be short, that is, the edge sensor 25 or the edge sensor 26 detects the skew state of the belt in detail, and the drive pulse X is driven each time the ON state is set, thereby the amount of tilting is determined. The force to increase the force to correct the skew of the belt is increased. With such control, the difference between the force that corrects the skew of the belt and the force that the belt tries to skew is reduced, so that the belt skew state can be checked in detail and the belt skew is prevented. be able to.

  A control method for preventing the skew of the belt will be specifically described with reference to FIGS. 10, 11, and 12.

  In the following description, it is assumed that the rotation angle of the cam is 90 ° and the edge sensor 25 is ON at the start of control.

  First, in FIG. 12, the cam rotation angle of 90 ° is first detected in step S01. Next, in step S02, a waiting time Y corresponding to a cam rotation angle of 90 °, that is, 2.5 seconds is set from the table shown in FIG. Next, in step S1, the ON / OFF state of the edge sensor 25 is determined. Since the edge sensor 25 is in an ON state at present (FIG. 3B), the drive pulse X is driven in step S2 to change the cam rotation angle by a unit drive amount (5 °). That is, the rotation angle of the cam is changed from 90 ° to 95 °. Then, the drive of the cam operation motor 33 is stopped for the waiting time Y of 2.5 seconds.

  Further, if the edge sensor 25 is in an ON state at the time when 2.5 seconds have elapsed, the process returns to step S01 and the rotation angle of the cam of 95 ° is detected. Subsequently, in step S02, a waiting time Y corresponding to a cam rotation angle of 95 °, that is, 3 seconds is set from the table shown in FIG. Next, in step S1, the ON / OFF state of the edge sensor 25 is determined. If it is OFF, the process proceeds to step S4. Here, the ON-OFF state of the edge sensor 26 is determined. If the edge sensor 26 is in the OFF state (if the skew of the belt is corrected), the process returns to step S01 again.

  Then, the process returns to step S01 to detect the cam rotation angle of 95 °. Subsequently, in step S02, a waiting time Y corresponding to a cam rotation angle of 95 °, that is, 3 seconds is set from the table shown in FIG. Next, in step S1, the ON-OFF state of the edge sensor 25 is determined. If it is OFF, the process proceeds to step S4. Here, the ON-OFF state of the edge sensor 26 is determined, and if it is in the ON state (FIG. 3C), the drive pulse X is driven in step S5 to change the cam rotation angle by a unit drive amount (5 °). Let In this case, the cam operation motor 33 rotates in the reverse direction, that is, changes the cam rotation angle from 95 ° to 90 °. Next, in step 6, the driving of the cam operating motor is stopped for 3 seconds, which is the waiting time Y when the cam rotation angle is 95 °. Here, if the edge sensor 26 is in the ON state when 3 seconds have elapsed, the process returns to step S01 to detect the cam rotation angle of 90 °. Thereafter, the above-described control in steps S01 to S6 is repeated. Such control prevents the belt from skewing.

  Next, a description will be given of the control for returning the belt running obliquely in the highly unstable state to the stable state.

  A case where the rotational drive amount of the rotational drive body (hereinafter referred to as “cam rotational angle”) changes from 140 ° to 145 ° in FIG. 11 will be described as an example.

  When the cam rotation angle changes from 140 ° to 145 ° in FIG. 11, the change in the tilt amount of the belt skew correction roller 7 (hereinafter simply referred to as “tilt amount”) is the same 5 ° change. Even so, it is considerably larger than the change in the small instability state (Δ2). That is, the amount of tilt of the belt skew correction roller 7 in FIG. 3B (or (c)) is large (Δ2). Therefore, since the amount of tilting is large, the force for correcting the skew of the belt is large. For this reason, in the large unstable state, the force for correcting the belt with respect to the skewing force is larger than that in the small unstable state. That is, the difference between the two forces becomes small in a large unstable state where the amount of tilting is large. Actually, when the amount of tilting changes in a highly unstable state, the change is large, so that the force that tries to correct the skew of the belt is slightly larger than the force that the belt tries to skew. Tend to be.

  Here, since the force for correcting the skew of the belt is slightly larger than the force of the belt for skewing, the belt that is skewed does not immediately move in the corrected direction. Even if it moves, it moves only in the direction that is gradually corrected. That is, in FIG. 3B (or (c)), the edge sensor 25 (or the edge sensor 26) remains ON for a while.

  In this state, if the waiting time Y in FIG. 6 is set short, the ON state of the edge sensor 25 (or edge sensor 26) continues for a while. Again, the edge sensor 25 (or the edge sensor 26) detects the ON state. Then, each time the tilting cam 32 is driven by a unit drive amount (drive pulse X), a force for correcting the belt is applied to the belt. Even if the cam rotation angle is changed by the same unit driving amount (5 °) as in the small instability state in the large instability state, the amount of tilting is large (Δ1 <Δ2). The belt is applied to the belt in an attempt to correct the skew of the belt with a larger force than in the case of.

  For example, in the case of shifting from the ON state to the OFF state after a short wait (immediately before the edge sensor 25 or the edge sensor 26 enters the OFF state), the waiting time Y in FIG. There is a case in which Y passes and the edge sensor 25 or the edge sensor 26 detects the ON state.

  When the ON state is detected, the driving pulse X is driven to change the rotation angle of the cam, and a force for correcting the skew is applied to the belt. For this reason, when a little more force is applied, an extra force is applied when trying to shift from the ON state to the OFF state, and the belt skew is corrected with a force larger than that in the small instability state described above. As a result, the belt is skewed again after exceeding the normal state, that is, the control for preventing the belt skew is excessively performed.

  In view of this, excessive control overshooting is suppressed by setting a long waiting time in a large unstable state.

  The specific control method for preventing the skew of the belt when the cam rotation angle changes from 140 ° to 145 ° is as described in FIG. Since this is the same as the control method for preventing the skew of the belt when the cam rotation angle changes from 90 ° to 95 °, the description thereof is omitted.

[Other embodiments]
The belt skew feeding correction device 1, the belt transport device 20 including the belt skew correction device 1, and the recording device 100 including the belt transport device 20 according to the present invention are based on the above-described configuration. However, it is of course possible to change or omit the partial configuration without departing from the gist of the present invention.

For example, the shape of the tilt cam 32 is not limited to the shape shown in FIG. Depending on the shape relative to the cam follower 31, it can be configured as appropriate. Further, the shape of the skew correction roller is not limited to the different diameter roller, and may be the same diameter roller.
In addition, the belt skew feeding correction device 1 of the present invention includes a belt transport device 20 mounted on a recording device other than the ink jet printer 100, a belt transport device 20 mounted on an electronic device other than the recording device, and the like. Alternatively, the present invention can also be applied to a belt conveying device 20 that is used independently for conveying articles.

FIG. 3 is a side cross-sectional view showing an outline of the internal structure of an ink jet printer to which the belt conveying device of the present invention is applied. The top view which shows the belt conveyance apparatus to which the belt skew feeding correction apparatus of this invention is applied. The top view which shows each state of the endless belt at the normal time (a), the left side skew (b), and the right side skew (c). The sectional side view which shows a tilting mechanism. The front view which shows the various shapes of a belt skew feeding correction | amendment roller. The timing chart of the skew correction control element of an endless belt. The flowchart which shows an example of skew correction control of an endless belt. The front view of the cam which makes the cam mechanism in this invention. The figure which shows the relationship between the rotation angle of a tilt cam (rotation angle of a rotational drive body), and the tilting amount of a belt skew feeding correction roller. An example of a table relating the rotation angle of the tilt cam (rotation drive amount of the rotary drive) and the set waiting time. FIG. 10 is a diagram illustrating a relationship between a rotation angle of a tilt cam (a rotation angle of a rotary drive body) and a tilt amount of a belt skew correction roller in the second embodiment. 9 is a flowchart illustrating an example of skew correction control of an endless belt according to a second embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Belt skew feeding correction device, 2 Conveying means, 3 Recording execution means, 4 Gate roller, 5 Driven roller, 6 Drive roller, 7 Belt skew feeding correction roller, 8 Endless belt, 9 Conveyance drive motor, 10 Conveyance surface, 11 Pore, 13 Recording Head, 19 Conversion Mechanism, 20 Belt Conveyor, 21 Small Diameter, 22 Large Diameter, 23 Left Edge, 24 Right Edge, 25 Left Edge Sensor, 26 Right Edge Sensor, 27 Light Emitting Section, 28 light receiving portion, 29 tilting mechanism, 30 roller support frame, 31 cam follower, 32 tilting cam, 33 cam operating motor, 34 biasing means, 35 swing arm, 36 tension spring, 37 shaft portion, 38 cam surface, 39 cam mechanism , 40 Rotating shaft, 41 Detection plate, 42 Cam position sensor, 43 Shaft portion, 44 Base end portion, 46 Control device, 5 Start switch, 100 Inkjet printer (recording device), P paper (recording material), A transport direction, B axis direction, D center roller diameter, d roller diameter at both ends, O rotation fulcrum, θ tilt angle, Q swing fulcrum, G arrow, H arrow, X drive pulse, Y waiting time, R rotation range of tilting cam

Claims (7)

A belt skew correction roller that corrects the skew of the endless belt by coming into contact with the surface of the endless belt wound between the driving roller and the driven roller;
A tilt mechanism that tilts the belt skew correction roller in a direction to correct the skew of the endless belt,
The tilt mechanism is
A driving body that is intermittently driven by a unit driving amount;
A conversion mechanism for converting the driving of the driving body into the tilting of the belt skew correction roller, with a relationship in which the tilt amount of the belt skew correction roller is determined corresponding to the driving amount of the driving body;
In the conversion mechanism, the relationship between the drive amount and the tilt amount is such that when the drive body advances the drive intermittently by the unit drive amount, the corresponding change amount of the tilt amount is small and large. is configured with a correlation with,
The correlation is a region where the degree of change in the tilt amount is small near the center of the driving range of the driving body, a region where the degree of change is large near both ends of the driving range, and the both regions are continuous. A belt skew feeding correction device, characterized in that the belt skew correction device is configured to be connected to the belt. The belt skew feeding correction device according to claim 1 ,
The driver is a rotary driver;
The conversion mechanism includes a cam mechanism, the cam constituting the cam mechanism rotates integrally with the rotation drive body, and the cam follower is positioned on the belt skew correction roller side.
The belt skew correcting device, wherein the correlation is constituted by a relative shape of the cam and the cam follower. In the belt skew feeding correction device according to claim 1 or 2 ,
The belt skew correction roller is a different diameter roller having a roller diameter that is larger at the center than at both ends. In the belt skew feeding correction device according to any one of claims 1 to 3 ,
ON / OFF switch type edge sensor for detecting each edge position in the belt width direction of the endless belt;
A control device that executes skew correction control of the endless belt by driving the driving body by the unit driving amount when any one of the edge sensors detects an ON state;
The control device determines whether or not the ON state of the edge sensor is released after a set waiting time has elapsed after driving the drive body by the unit driving amount, and the ON state is released. If not, the driving body is further driven by the unit driving amount, and after the waiting time has elapsed, a determination is again made as to whether the ON state of the edge sensor has been released, and the same operation is performed. A belt skew feeding correcting device, wherein the belt skew feeding correcting device is configured to repeat every waiting time within a preset limit. 5. The belt skew correction device according to claim 4 , wherein the waiting time is set in accordance with a value of a driving amount when the driving body is driven by the unit driving amount. Line correction device. A driving roller for applying a conveying force to the endless belt;
A driven roller disposed opposite to the drive roller and holding the endless belt in tension with the drive roller;
An endless belt wound between the driving roller and the driven roller;
A belt skew correction device including a belt skew correction roller that corrects the skew of the endless belt by contacting the surface of the endless belt;
6. The belt conveying device according to claim 1, wherein the belt skew correcting device is the belt skew correcting device according to any one of claims 1 to 5 . A belt conveying device for holding and conveying a recording material;
A recording execution unit that performs recording on the recording material held and conveyed by the belt conveying device;
The recording apparatus according to claim 6 , wherein the belt conveyance device is a belt conveyance device according to claim 6 .

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