JP6818641B2 - Media detection device and image forming device - Google Patents

Description

The present invention relates to a medium detection device and an image forming device, and is suitable for application to, for example, an electrophotographic printer.

Conventionally, as an image forming apparatus, for example, a toner image is generated by an exposure apparatus, the toner image is carried on a traveling intermediate transfer belt, and paper as a medium is conveyed along a conveying path by a conveying portion made of a roller or the like. In some cases, a toner image is transferred from an intermediate transfer belt to paper, and the image is printed by applying heat or pressure to the paper to fix the toner image.

This image forming apparatus may print an image on so-called label paper. The label paper has a configuration in which, for example, a plurality of label paper pieces having a small area and high adhesiveness on the back surface are attached along the paper transport direction to a mount having a large area and high surface peelability. With this label paper, it is necessary to print the image according to the position of the label paper piece. Therefore, in the image forming apparatus, a transmissive sensor is configured by arranging a light emitting element on one side of the label paper and a light receiving element on the other side, and light is emitted from only the mount and the mount and the label paper piece. By utilizing the fact that the transmittances of the labels are different, the position of the tip of the label paper piece can be detected.

Further, as this label paper, paper having various widths is used like ordinary paper. Therefore, in the image forming apparatus, it is conceivable to provide carriages that can move in the width direction on both sides of the paper transport path, and mount a light emitting element and a light receiving element on these carriages, respectively. In this case, in the image forming apparatus, when moving the carriages provided on both sides of the transport path in the width direction, it is necessary to adjust the positions so that the positions of the light emitting element and the light receiving element are aligned with each other. Therefore, it is conceivable that the image forming apparatus incorporates an interlocking mechanism that interlocks the movements of the carriages in the width direction with each other.

By the way, in the image forming apparatus, a paper jam may occur in the paper transport path, or foreign matter such as paper dust may adhere to the surface of the light receiving element, and maintenance work is required to remove these. In this maintenance work, the image forming apparatus performs an opening / closing operation of the transport path such that both sides of the transport path in the transport unit are temporarily separated from each other and returned to their original positions after the maintenance work.

However, in the image forming apparatus, when the opening / closing operation is performed in the transport unit, if the interlocking of each carriage in the interlocking mechanism is temporarily released, the detection accuracy is lowered. Further, in the image forming apparatus, adjustment work is required to realign the carriages with each other, which requires a great deal of time and effort. Therefore, in the image forming apparatus, for example, carriages that can be moved in the width direction by rotating the screw shafts are provided on both sides of the paper transport path, and the transport paths are opened and closed while both screw shafts are interlocked with each other via gears or the like. Those have been proposed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-52579 (FIGS. 7 and 9)

However, in the image forming apparatus having such a configuration, it is necessary to insert the screw shaft into the carriage while rotating it when manufacturing the carriage and the interlocking mechanism. Further, in the image forming apparatus, it is also necessary to align the positions of the carriages facing each other across the transport path while using, for example, a dedicated jig for aligning the positions of the light emitting element and the light receiving element. Moreover, in the image forming apparatus, the same work is required when maintenance work such as disassembling the peripheral portion of the carriage and the interlocking mechanism is performed. That is, the image forming apparatus has a problem that the so-called workability is poor because the operator is forced to perform various complicated operations during manufacturing and maintenance work.

The present invention has been made in consideration of the above points, and an object of the present invention is to propose a medium detection device and an image forming device that can maintain the accuracy of detecting a medium and ensure workability during manufacturing and maintenance work. Is what you do.

In order to solve such a problem, in the medium detection device of the present invention, the first main body portion arranged on one side of the transport path for transporting the medium along a predetermined transport direction and the first main body portion arranged on the other side of the transport path are arranged. The second main body, the main body rotating part that rotates the first main body with respect to the second main body, and the central axis around the central axis that is parallel to one surface and intersects the transport direction. Is rotatably supported around the central axis by the first main body portion, and has a thread groove formed on the peripheral side surface, and the first screw shaft is one of the intersecting directions. The first alignment portion provided at the end on the first crossing direction side and the thread groove is omitted and the central axis are aligned along the crossing direction, and are rotatably supported around the central axis by the second main body portion. The second screw shaft having a thread groove formed on the peripheral side surface and the second screw shaft are provided at the end portion on the first crossing direction side corresponding to the first alignment portion, and the screw groove is omitted. It has a second alignment portion and a first insertion hole through which the first screw shaft is inserted, and a screw groove screwed with the screw groove of the first screw shaft is formed on the inner peripheral surface of the first insertion hole. It has a first carriage that moves in the intersecting direction with the rotation of the first screw shaft, and a second insertion hole through which the second screw shaft is inserted, and the second screw is formed on the inner peripheral surface of the second insertion hole. A screw groove is formed to be screwed with the screw groove of the shaft, and the second carriage that moves in the intersecting direction with the rotation of the second screw shaft is provided, and one of the first carriage and the second carriage is provided to provide light to the transport path. Alternatively, a transmitting element that emits an electromagnetic wave, a receiving element that is provided on the other side of the first carriage and the second carriage and receives light or an electromagnetic wave from a transport path, and a central axis that is common to the rotating portion of the main body are rotated. The interlocking unit that links the rotation of the first screw shaft and the rotation of the second screw shaft, the driving force supply unit that supplies the driving force to the interlocking unit, and the driving force supply unit are controlled via the intermediary rotating body. A control unit is provided , and the control unit supplies the driving force from the driving force supply unit to the interlocking unit and rotates the first screw shaft and the second screw shaft, respectively, to make the first carriage and the second carriage first. After reaching the alignment portion and the second alignment portion, the first screw shaft and the second screw shaft are rotated in opposite directions to make the thread groove of the first insertion hole in the first carriage first screw. While screwing with the thread groove of the cru shaft, the thread groove of the second insertion hole in the second carriage is screwed with the thread groove of the second screw shaft, and the first carriage and the second carriage are kept in the same phase. It is moved in the direction away from the 1st alignment part and the 2nd alignment part .

The image forming apparatus of the present invention is also a medium detection device described above, an image forming unit for fixing by transferring an image formed by the current image agents provided, the control unit receives a result of light or electromagnetic wave by the receiving element The position of the medium was determined based on the above, and the image forming unit was made to transfer and fix the image according to the position of the medium determined by the control unit .

In the present invention, the first carriage is positioned in the first alignment portion of the first screw shaft, and the second carriage is positioned in the second alignment portion of the second screw shaft, whereby light or electromagnetic waves from the transmitting element are located. Can be aligned with each other so that the light can be received by the receiving element. Then, in the present invention, only by initiating the interlocking of both screw shafts by the interlocking portion, the first carriage and the second carriage are moved to the first aligning portion and the second while keeping the relative positions of the transmitting element and the receiving element aligned. It can be moved away from the alignment part .

According to the present invention, it is possible to realize a medium detection device and an image forming device that can achieve both maintenance of accuracy for detecting a medium and ensuring workability during manufacturing and maintenance work.

It is a schematic diagram which shows the structure of the image forming apparatus. It is a schematic perspective view which shows the structure of the paper. It is a schematic perspective view which shows the structure of the paper detection sensor part. It is a schematic diagram which shows the structure of the interlocking part and the opening and closing of the upper part of a main body. It is a schematic perspective view which shows the structure of the upper sensor part and the lower sensor part. It is a schematic diagram which shows the position of each carriage at the time of assembly. It is a schematic diagram which shows the position of each carriage at the time of operation. It is a schematic diagram which shows the elimination (1) of the misalignment between carriages. It is a schematic diagram which shows the elimination (2) of the misalignment between carriages.

Hereinafter, embodiments for carrying out the invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

[1. Configuration of image forming apparatus]
As shown in FIG. 1, the image forming apparatus 1 according to the present embodiment is configured as an electrophotographic printer, for example, printing a desired color image on a long paper P. .. The image forming apparatus 1 is roughly divided into a main body unit 2 that performs printing processing, a transport cutting unit 3 that transports and cuts paper P, and a roll feeder unit 4 that supplies paper P. Further, inside the main body 2, a control unit 5 that controls the whole is provided.

The control unit 5 is mainly composed of a CPU (Central Processing Unit) (not shown), and various processes related to printing are performed by reading a predetermined program from a ROM (Read Only Memory), a flash memory, or the like (not shown) and executing the program. I do. Further, the control unit 5 has a storage unit including a RAM (Random Access Memory), a hard disk drive, a flash memory, and the like inside, and stores various information in this storage unit.

The control unit 5 is wirelessly or wiredly connected to a higher-level device (not shown) such as a personal computer via a communication processing unit (not shown). When the host device gives image data representing an image to be printed and is instructed to print the image data, the control unit 5 starts a printing process of forming an image on the surface of the paper P.

For convenience of explanation, in the following, the roll feeder unit 4 side is the front side, the main body 2 side is the rear side, the front side of the paper in FIG. 1 is the left side, the back side is the right side, and the upper side and the lower side are defined. I will explain it.

Paper P as a medium is wound around the peripheral side surface of a core material (not shown) along the left-right direction to form a roll (hereinafter, this portion is referred to as a roll portion PR), and is used during printing. One end is peeled off from the outermost circumference, and the vehicle travels along a transport path described later. As shown in FIGS. 2A and 2B, this paper P is a so-called label paper, and is composed of a mount PM and a plurality of label paper pieces PL. The mount PM is long along the traveling direction, and the peelability of the surface is enhanced. The label paper piece PL has a relatively small rectangular shape and has an enhanced adhesiveness on the back surface, and is attached to the front surface of the mount PM so as to be aligned at predetermined intervals along the traveling direction.

The roll feeder unit 4 (FIG. 1) is attached to the front side of the transport cutting portion 3 by the attachment arm 7, and the roll portion PR of the paper P is rotatably held by the roll holder 8 provided on the front side thereof. There is. When one end of the paper P is peeled off from the outermost circumference of the roll portion PR, the paper P is pulled out rearward and downward along the arrow E1.

The transport cutting portion 3 is provided with a guide roller 11 and a transport portion 12 in the housing 10. The guide roller 11 is provided on the lower side of the front side of the housing 10 and is formed in a cylindrical shape with the central axis along the left-right direction so that the housing 10 can rotate with the central axis as the center of rotation. Is supported by. The guide roller 11 guides the paper P drawn out from the roll portion PR while abutting against the lower portion of the peripheral side surface, advances it diagonally backward and upward along the arrow E2, and delivers it to the conveying portion 12.

The transport section 12 is formed with a transport path 12Y along the front-rear direction, and along the transport path 12Y, a transport roller pair 13, a paper detection sensor unit 14, and a paper cutting unit 18 are provided in this order from the front. There is. The transport roller pair 13 is composed of two transport rollers arranged so as to sandwich the transport path 12Y from above and below, and by appropriately rotating each transport roller, the paper P is advanced with the rear direction as the transport direction. ..

The paper detection sensor unit 14 as a medium detection device is roughly divided into a main body lower portion 15 that mainly occupies the lower portion of the transport path 12Y (FIG. 1) and a main body upper portion 16 that mainly occupies the upper portion of the transport path 12Y. It is composed of. The paper detection sensor unit 14 has a transmission sensor and a reflection sensor, and detects the presence or absence of the paper P and the tip position of the label paper piece PL (FIG. 2) on the paper P by utilizing the reflection and transmission of light. Then, the obtained detection result is notified to the control unit 5.

The paper cutting unit 18 incorporates a cutter for cutting the paper P and a transport roller or the like for transporting the paper P. Based on the control of the control unit 5, the paper cutting unit 18 cuts the paper P in accordance with the position of the label paper piece PL detected by the paper detection sensor unit 14. Further, the transport unit 12 transports the paper P along the transport path 12Y by the transport roller pair 13 and the transport roller pair in the paper cutting portion 18, and advances the paper P into the rear main body portion 2.

The main body 2 is arranged so that a plurality of primary transfer portions 21 are aligned in the front-rear direction on the upper side inside the rectangular parallelepiped housing 20. Each primary transfer unit 21 forms toner images of a plurality of colors under the control of the control unit 5, for example, and transfers these to the intermediate transfer belt 31 of the intermediate transfer unit 22. The intermediate transfer unit 22 appropriately runs the intermediate transfer belt 31 stretched between the plurality of belt rollers, and causes the toner image transferred from the primary transfer unit 21 to reach the secondary transfer unit 24.

The central transport unit 23 transports the paper P rearward along the transport path 20Y by a plurality of transport roller pairs, and detects the tip position of the label paper piece PL (FIG. 2) on the paper P by the plurality of detection sensors. This is controlled to match the position of the toner image carried on the intermediate transfer belt 31 so that it reaches the secondary transfer unit 24. The secondary transfer unit 24 sandwiches the intermediate transfer belt 31 and the paper P between the rollers arranged above and below the transport path 20Y, rotates each roller, and transfers the toner image from the intermediate transfer belt 31 to the paper P. Transfer to.

The fixing portion 25 heats and rotates each fixing roller arranged on the lower side and the upper side of the transport path 20Y, respectively, and applies heat and pressure to the paper P to fix the toner image, and rearly rearly Hand over to the transport unit 26. The rear transport unit 26 transports the paper P backward along the transport path 20Y. Incidentally, the paper P discharged rearward from the main body 2 is wound by a paper winding unit (not shown) installed on the rear side of the main body 2.

[2. Paper detection sensor configuration]
As shown in FIGS. 3 (A) and 3 (B) and the left side view in FIGS. 4 (A) and 4 (B), the paper detection sensor unit 14 has a lower main body portion 15 with respect to the lower main body portion 15. The upper body portion 16 on the upper side is supported via a rotating portion 17 as a main body rotating portion. The rotating portion 17 can rotate the upper body 16 with respect to the lower body 15 about a virtual central axis along the left-right direction. Incidentally, this central axis is parallel to the paper P to be conveyed and is along the intersecting direction (that is, the left-right direction) intersecting the rear direction which is the conveying direction.

Therefore, as shown in FIGS. 3A and 4A, the paper detection sensor unit 14 is in a state in which the lower side of the main body upper portion 16 faces the upper side of the main body lower portion 15 (hereinafter, this is a closed state). As shown in FIGS. 3 (B) and 4 (B), the transition to a state in which the upper body 16 is rotated with respect to the lower body 15 (hereinafter, this is referred to as an open state). Can be done.

The lower portion 15 of the main body as the first main body portion is formed in a rectangular parallelepiped shape that is relatively short in the vertical direction as a whole, and is about half the lower side of the paper cutting portion 18 (FIG. 1) near the center in the front-rear direction in the upper portion. There is a space to accommodate. Further, a lower sensor portion 50 is arranged at a portion of the lower portion 15 of the main body that is on the front side of the paper cutting portion 18.

The upper portion 16 of the main body as the second main body portion is formed in a rectangular parallelepiped shape that is relatively short in the vertical direction as a whole, and is about the upper half of the paper cutting portion 18 (FIG. 1) near the center in the front-rear direction in the lower portion. There is a space to accommodate. Further, the front upper portion of the main body upper portion 16 is formed with an inclined surface as if it was cut off diagonally. Further, the upper sensor portion 70 is arranged at a portion of the upper portion 16 of the main body that is on the front side of the paper cutting portion 18.

[2-1. Lower sensor configuration]
The lower sensor portion 50 (FIG. 3) has a configuration in which the left side plate 15L and the right side plate 15R fixed to the lower portion 15 of the main body support the lower sensor unit 50 (FIG. 3) from the vicinity of both left and right ends. The left side plate 15L and the right side plate 15R are formed in a thin plate shape in the left-right direction, and both left and right ends of the lower first regulation shaft 51, the lower screw shaft 52, and the lower second regulation shaft 53 shown in FIG. 5 (B). It supports each neighborhood. For convenience of explanation, in the following, the left-right direction that intersects the rear direction, which is the transport direction, is also referred to as an intersection direction. In the following, the right direction of one of the crossing directions is also referred to as a first crossing direction, and the left direction, which is the opposite direction, is also referred to as a second crossing direction.

The lower first regulation shaft 51 and the lower second regulation shaft 53 are formed in an elongated columnar shape along the central axis in the left-right direction, and are rotatably supported by the left side plate 15L and the right side plate 15R (FIG. 3), respectively. Has been done. Incidentally, the lower first regulation shaft 51 is longer in the left-right direction than the lower second regulation shaft 53.

The lower screw shaft 52 as the first screw shaft is formed in an elongated columnar shape along the central axis in the left-right direction, and is a screw portion that occupies a range of about 3/4 to about 7/8 from the vicinity of the left end. It is composed of 52S and an incomplete threaded portion 52F that occupies a range of about 1/4 to about 1/8 from the vicinity of the right end. A spiral groove (thread groove) is engraved on the peripheral side surface of the threaded portion 52S. On the other hand, the incompletely threaded portion 52F as the first alignment portion is not engraved with a thread groove. The lower screw shaft 52 is rotatably supported by the left side plate 15L and the right side plate 15R (FIG. 3), respectively.

A lower interlocking gear 54 is attached near the left end of the lower screw shaft 52. The lower interlocking gear 54 is formed in the shape of a thin disk in the left-right direction, and a plurality of teeth are formed on the peripheral side surface thereof to form a gear. The lower interlocking gear 54 is fixed to the lower screw shaft 52 by inserting the lower screw shaft 52 into the hole formed in the center.

Further, the lower sensor unit 50 is provided with a lower carriage 55. The lower carriage 55 as the first carriage is formed in a relatively small rectangular parallelepiped shape, and has insertion holes 55H1, 55H2, and 55H3 penetrating in the left-right direction, respectively. Of these, the insertion hole 55H2 as the first insertion hole has a spiral groove (that is, a screw groove) engraved on the inner peripheral surface, and is screwed with the screw groove formed in the screw portion 52S of the lower screw shaft 52. .. On the other hand, the insertion holes 55H1 and 55H3 are not formed with grooves on the inner peripheral side surfaces, and slide smoothly with respect to the lower first regulation shaft 51 and the lower second regulation shaft 53, respectively. Further, the incompletely threaded portion 52F of the lower screw shaft 52 can also smoothly slide with respect to the insertion hole 55H2.

The lower carriage 55 is moved in the vertical and front-rear directions with respect to the lower portion 15 of the main body and in each direction by inserting the lower first regulation shaft 51 and the lower second regulation shaft 53 into the insertion holes 55H1 and 55H3, respectively. Each rotation is regulated. In other words, the lower first regulation shaft 51 and the lower second regulation shaft 53 serve as reference for the positions of the lower carriage 55 in the front-rear direction and the up-down direction.

When the lower screw shaft 52 is rotated in either direction while the lower carriage 55 is inserted into the threaded portion 52S of the lower screw shaft 52, the lower carriage 55 is screwed into each other's screw grooves with the insertion hole 55H2. Therefore, it moves to the left or right along the lower screw shaft 52, the lower first regulation shaft 51, and the lower second regulation shaft 53.

An urging member 56 as a first urging portion is attached in the vicinity of the right end of the lower screw shaft 52. The urging member 56 is formed in a relatively small columnar shape along the central axis in the left-right direction, and is made of an elastic material such as rubber. Further, the urging member 56 has its right side surface in contact with the right side plate 15R (FIG. 3).

Further, the length in the left-right direction of the incompletely threaded portion 52F of the lower screw shaft 52 excluding the insertion portion of the urging member 56 is slightly shorter than the length in the left-right direction of the lower carriage 55. Therefore, in the lower sensor unit 50, if the lower carriage 55 is located near the right end and the insertion hole 55H2 is inserted into the incomplete threaded portion 52F, the urging member 56 urges the lower carriage 55 to the left. be able to.

The lower carriage 55 incorporates a reflection sensor 57 and a light receiving element 58 at a rearward portion and a frontward portion on the upper side. The reflection sensor 57 incorporates a light emitting element and a light receiving element, irradiates light upward from the light emitting element, receives light traveling from above by the light receiving element, and controls the light receiving result by the light receiving element. Notify Part 5 (Fig. 1). The light receiving element 58 as a receiving element receives light from above and notifies the control unit 5 of the obtained light receiving result.

[2-2. Upper sensor configuration]
The upper sensor unit 70 (FIG. 3) is supported from the vicinity of both left and right ends by the left side plate 16L and the right side plate 16R fixed to the upper part 16 of the main body, and has a configuration similar to that of the lower sensor unit 50. That is, as shown in FIG. 5A, the upper sensor unit 70 is configured substantially in the same manner as the lower first regulation shaft 51, the lower screw shaft 52, and the lower second regulation shaft 53 of the lower sensor unit 50. A first regulation shaft 71, an upper screw shaft 72, and an upper second regulation shaft 73 are provided.

Like the lower screw shaft 52, the upper screw shaft 72 as the second screw shaft is formed in an elongated columnar shape along the central axis in the left-right direction, and is about 3/4 to about 7 / of the whole from the vicinity of the left end. It is composed of a threaded portion 72S that occupies the range of 8 and an incomplete threaded portion 72F that occupies a range of about 1/4 to about 1/8 from the vicinity of the right end. Similar to the threaded portion 52S, the threaded portion 72S has a spiral groove (threaded groove) engraved on the peripheral side surface thereof. Incidentally, the pitch (cycle) of the thread grooves in the threaded portion 72S is the same as that of the threaded portion 52S. On the other hand, the incompletely threaded portion 72F as the second alignment portion is not carved with a thread groove like the incompletely threaded portion 52F.

The upper first regulation shaft 71, the upper screw shaft 72, and the upper second regulation shaft 73 are rotatably supported by the left side plate 16L and the right side plate 16R (FIG. 3), respectively. Further, an upper interlocking gear 74 having the same configuration as the lower interlocking gear 54 is attached near the left end of the upper screw shaft 72.

The upper sensor unit 70 is provided with an upper carriage 75. The upper carriage 75 as the second carriage is formed in a relatively small rectangular parallelepiped shape like the lower carriage 55, and has the same insertion holes 75H1, 75H2 and 75H3 as the insertion holes 55H1, 55H2 and 55H3, respectively. There is. Of these, the insertion hole 75H2 as the second insertion hole has a spiral groove (that is, a screw groove) engraved on the inner peripheral surface like the insertion hole 55H2, and is formed in the threaded portion 72S of the upper screw shaft 72. Screw with the thread groove.

Similar to the case of the lower carriage 55, the upper carriage 75 has the upper first regulation shaft 71 and the upper second regulation shaft 73 inserted into the insertion holes 75H1 and 75H3, respectively, so that the upper carriage 75 is in the vertical direction and the front-rear direction with respect to the upper body 16. Movement to and rotation in each direction are regulated respectively. In other words, the upper first regulation shaft 71 and the upper second regulation shaft 73 serve as a reference for the positions of the upper carriage 75 in the front-rear direction and the up-down direction.

When the upper screw shaft 72 is rotated in either direction while the upper carriage 75 is inserted into the threaded portion 72S of the upper screw shaft 72, the upper carriage 75 is screwed into each other's screw grooves with the insertion hole 75H2. Therefore, it moves to the left or right along the upper screw shaft 72, the upper first regulation shaft 71, and the upper second regulation shaft 73.

In the vicinity of the right end of the upper screw shaft 72, an urging member 76 as a second urging portion having the same configuration as the urging member 56 is attached. The right side surface of the urging member 76 is in contact with the right side plate 16R (FIG. 3).

Further, the length in the left-right direction of the incompletely threaded portion 72F of the upper screw shaft 72 excluding the insertion portion of the urging member 76 is slightly shorter than the length in the left-right direction of the upper carriage 75. Therefore, in the upper sensor unit 70, as in the case of the lower sensor unit 50, if the upper carriage 75 is located near the right end and the insertion hole 75H2 is inserted into the incomplete thread portion 72F, the urging member 76 raises the upper carriage 75. The carriage 75 can be urged to the left.

Further, the upper carriage 75 incorporates a light emitting element 78 at a position closer to the front on the lower side. The light emitting element 78 as a transmitting element emits light downward. The light emitting element 78 is used as a transmissive sensor that, in combination with the light receiving element 58 incorporated in the lower carriage 55, irradiates the paper P conveyed on the transport path 12Y with light and receives the light transmitted through the paper P. It is supposed to work. That is, in the paper detection sensor unit 14, the light emitting element 78 is located on the one side to which the label paper piece PL is attached, and the light receiving element 58 or the like is located on the other side on the opposite side of the conveyed paper P. There is.

[2-3. Opening and closing of the paper detection sensor]
By the way, on the left side of the paper detection sensor unit 14, as shown in FIGS. 4A and 4B, an intermediary gear 82 that rotates about a central axis common to the rotating unit 17 is provided. The intermediary gear 82 as an intermediary rotating body is configured as a gear, and can freely rotate with respect to the lower portion 15 of the main body and the rotating portion 17.

Further, on the left side of the paper detection sensor unit 14, a lower intermediary gear group 83 including a plurality of gears for transmitting a driving force between the lower interlocking gear 54 and the intermediary gear 82, and an upper interlocking gear 74 and an intermediary gear 82 are provided. An upper intermediary gear group 84, which is composed of a plurality of gears for transmitting a driving force between the gears, is provided. Each gear of the lower intermediary gear group 83 is supported by a gear support member (not shown) so that it can freely rotate while maintaining its position with respect to the lower portion 15 of the main body. Similarly, each gear of the upper intermediary gear group 84 is supported by a gear support member (not shown) so that it can rotate freely while maintaining its position with respect to the upper portion 16 of the main body. For convenience of explanation, in the following, the lower interlocking gear 54, the upper interlocking gear 74, the intermediary gear 82, the lower intermediary gear group 83, and the upper intermediary gear group 84 are collectively referred to as an interlocking unit 80.

Incidentally, some gears in the lower intermediary gear group 83 are provided with a disk-shaped rotary knob (not shown). Therefore, in the interlocking unit 80, when the rotary knob is manually rotated by a maintenance worker, each gear can be interlocked and rotated.

With this configuration, in the paper detection sensor unit 14, the interlocking unit 80 can interlock and rotate the lower screw shaft 52 and the lower interlocking gear 54 and the upper screw shaft 72 and the upper interlocking gear 74 by the same amount of rotation. it can. As a result, in the paper detection sensor unit 14, the lower carriage 55 and the upper carriage 75 can be interlocked with each other, that is, they can be moved in the same direction and by the same distance.

Further, in the paper detection sensor unit 14, the rotation center of the main body upper portion 16 with respect to the main body lower portion 15 coincides with the rotation center of the intermediary gear 82. As a result, in the paper detection sensor unit 14, the upper portion 16 of the main body is opened (FIG. 4 (A)) or closed (FIG. 4 (B)) with respect to the lower portion 15 of the main body, and further, in any of the states in between. Also, the gears of the interlocking portion 80 can be maintained in a state of being meshed with each other, and the relative positions of the lower carriage 55 and the upper carriage 75 in the left-right direction can be maintained.

[2-4. Assembling the paper detection sensor unit]
By the way, the paper detection sensor unit 14 receives the light emitted from the light emitting element 78 by aligning the positions of the lower carriage 55 and the upper carriage 75 in the left-right direction (hereinafter, also referred to as phases) with each other at the time of manufacture. It is necessary to receive light by 58. Therefore, the paper detection sensor unit 14 uses the incompletely threaded portion 52F of the lower screw shaft 52 and the incompletely threaded portion 72F of the upper screw shaft 72 to align the phases of the lower carriage 55 and the upper carriage 75. There is.

Specifically, in the paper detection sensor unit 14, the lower portion 15 of the main body is first assembled. That is, in the paper detection sensor unit 14, as shown in FIG. 6, the incomplete screw portion 52F on the right end side of the lower screw shaft 52 and the vicinity of the right end of the lower first regulation shaft 51 and the lower second regulation shaft 53 are formed. It is inserted into the insertion holes 55H2, 55H1 and 55H3 (FIG. 5) of the lower carriage 55, respectively. A urging member 56 is inserted through the right end of the lower screw shaft 52.

Subsequently, in the paper detection sensor unit 14, the vicinity of the left end and the vicinity of the right end of the lower first regulation shaft 51, the lower screw shaft 52, and the lower second regulation shaft 53 are inserted into the left side plate 15L and the right side plate 15R of the lower part 15 of the main body, respectively. As a result, it is attached to the lower part 15 of the main body. At this time, the lower carriage 55 is inserted into the incompletely threaded portion 52F of the lower screw shaft 52 in the vicinity of the right side plate 15R, and is urged to the left by the urging member 56.

Next, in the paper detection sensor unit 14, the assembly of the upper body 16 is performed in substantially the same manner as the lower body 15. Specifically, in the paper detection sensor unit 14, the incomplete screw portion 72F on the right end side of the upper screw shaft 72 and the vicinity of the right end of the upper first regulation shaft 71 and the upper second regulation shaft 73 are inserted into the upper carriage 75. It is inserted into the holes 75H2, 75H1 and 75H3 (FIG. 5), respectively. A urging member 76 is inserted through the right end of the upper screw shaft 72.

Subsequently, in the paper detection sensor unit 14, the vicinity of the left end and the vicinity of the right end of the upper first regulation shaft 71, the upper screw shaft 72, and the upper second regulation shaft 73 are inserted into the left side plate 16L and the right side plate 16R of the main body upper portion 16, respectively. As a result, it is attached to the upper part 16 of the main body. At this time, the upper carriage 75 is inserted into the incompletely threaded portion 72F of the upper screw shaft 72 in the vicinity of the right side plate 16R and is urged to the left by the urging member 76, as in the case of the lower carriage 55. It becomes.

As a result, in the paper detection sensor unit 14, as shown in FIG. 6, the lower carriage 55 and the upper carriage 75 are close to the right side plates 15R and 16R with the urging members 56 and 76, respectively, and left and right of each other. It is in a state where the position (that is, the phase) in the direction is matched.

Further, in the paper detection sensor unit 14, the interlocking unit 80 (FIG. 4), that is, the lower interlocking gear 54, the upper interlocking gear 74, the intermediary gear 82, the lower intermediary gear group 83, and the upper intermediary unit 80 (FIG. 4) on the left side portion of the main body lower portion 15 and the main body upper portion 16. The gear group 84 is incorporated. Here, in the paper detection sensor unit 14, each gear is rotated appropriately because it meshes with the adjacent gear, and the lower screw shaft 52 and the upper screw shaft 72 to which the lower interlocking gear 54 and the upper interlocking gear 74 are attached also rotate, respectively. Will be done. At this time, the paper detection sensor unit 14 rotates the lower screw shaft 52 and the upper screw shaft 72 in the rotation direction when the lower carriage 55 and the upper carriage 75 are moved to the right (hereinafter, this is referred to as a right movement rotation direction). As such, each gear is meshed while being rotated appropriately.

Therefore, the lower carriage 55 and the upper carriage 75 maintain the state of being inserted into the incompletely threaded portions 52F and 72F of the lower screw shaft 52 and the upper screw shaft 72, respectively. In other words, the lower screw shaft 52 and the upper screw shaft 72 are, so to speak, idle because the incompletely threaded portions 52F and 72F are inserted into the insertion holes 55H2 and 75H2 of the lower carriage 55 and the upper carriage 75, respectively. Become.

After that, the paper detection sensor unit 14 rotates each gear of the interlocking unit 80 in the rotation direction when the lower carriage 55 and the upper carriage 75 are moved to the left (hereinafter, this is referred to as a left movement rotation direction). At this time, since the lower carriage 55 is urged to the left by the urging member 56, the left end of the insertion hole 55H2 is pressed against the right end of the screw portion 52S on the lower screw shaft 52 to start screwing and to the left. Start moving. At the same time, since the upper carriage 75 is urged to the left by the urging member 76, the left end of the insertion hole 75H2 is pressed against the right end of the screw portion 72S on the upper screw shaft 72 to start screwing and to the left. Start moving to.

As a result, in the paper detection sensor unit 14, as shown in FIG. 7, the lower carriage 55 and the upper carriage 75 can start moving to the left while keeping their positions in the left-right direction (that is, in phase). it can. After that, in the paper detection sensor unit 14, each gear of the interlocking unit 80 is appropriately rotated, and the lower screw shaft 52 and the upper screw shaft 72 are rotated in conjunction with each other, so that the lower carriage is within the range of the screw portions 52S and 72S. The 55 and the upper carriage 75 can be moved in the left-right direction while maintaining their phases.

By the way, in the light receiving element 58 and the light emitting element 78 mounted on the lower carriage 55 and the upper carriage 75, respectively, the allowable amount of misalignment is, for example, ± 1.0 [mm]. This means that the light emitted from the light emitting element 78 can be received by the light receiving element 58 if the positional deviation in the left-right direction of the lower carriage 55 and the upper carriage 75 is within ± 1.0 [mm].

Therefore, the lower screw shaft 52 and the upper screw shaft 72 have a diameter of about 4 [mm], and are specified in ISO 724: 1993, JIS B 0205: 2001, etc. in the threaded portions 52S and 72S, respectively. A spiral groove equivalent to a screw called "M4" is carved. In this "M4" screw, the pitch, which is the period between the grooves, is 0.7 [mm].

That is, in the paper detection sensor unit 14, when each gear of the interlocking unit 80 is rotated to start the movement of the lower carriage 55 and the upper carriage 75 at the same time, there is a possibility that a position shift of up to one pitch may occur between the two. However, this can be suppressed to 0.7 [mm] at the maximum, that is, within the range of ± 1.0 [mm] described above.

In other words, in the paper detection sensor unit 14, the allowable amount of misalignment in the light receiving element 58 and the light emitting element 78 is larger than the pitch of the thread grooves in the lower screw shaft 52 and the upper screw shaft 72. As a result, the paper detection sensor unit 14 can receive the light emitted from the light emitting element 78 by the light receiving element 58, so that the tip position and the like of the label paper piece PL (FIG. 2) can be detected with high accuracy.

By the way, in the paper detection sensor unit 14, when disassembly or reassembly is performed as maintenance work, the phase of the lower carriage 55 and the upper carriage 75 is out of phase, that is, the amount of misalignment is ± 1.0 [mm. ] May be more than that. Here, as an example, it is assumed that the lower carriage 55 is located on the right side of the upper carriage 75 as shown in FIG.

In such a case, in the paper detection sensor unit 14, first, each gear of the interlocking unit 80 is rotated in the clockwise rotation direction by the operation of the maintenance worker, and the lower screw shaft 52 and the upper screw shaft 72 are also rotated accordingly. Move to the right Rotate in the direction of rotation. As a result, in the paper detection sensor unit 14, the lower carriage 55 and the upper carriage 75 move to the right, that is, to the first crossing direction, while maintaining their misalignment with each other.

After a while, in the paper detection sensor unit 14, as shown in FIG. 9, the lower carriage 55 reaches the vicinity of the right end of the lower screw shaft 52, that is, the incomplete screw portion 52F, abuts on the urging member 56, and the right side plate 15R. It becomes a state close to. After that, in the upper portion 16 of the main body of the paper detection sensor unit 14, the upper carriage 75 continues to move to the right due to the rotation of the upper screw shaft 72 in the rightward rotation direction. On the other hand, in the lower portion 15 of the main body, although the lower screw shaft 52 rotates in the clockwise rotation direction, the incomplete screw portion 52F idles with respect to the inner groove in the insertion hole 55H2 of the lower carriage 55, so that the lower carriage 55 Keep the position of.

That is, in the paper detection sensor unit 14, although the lower screw shaft 52 and the upper screw shaft 72 rotate in conjunction with each other, the misalignment of the lower carriage 55 and the upper carriage 75 is gradually reduced by moving only the upper carriage 75. You can go.

Eventually, in the paper detection sensor unit 14, the upper carriage 75 reaches the vicinity of the right end of the upper screw shaft 72, that is, the incomplete screw portion 72F, and as shown in FIG. 6, abuts on the urging member 76 and reaches the right side plate 16R. It will be in close proximity. As a result, in the paper detection sensor unit 14, the phases of the lower carriage 55 and the upper carriage 75 are aligned, that is, the same state as at the time of assembly. After that, in the paper detection sensor unit 14, the gears of the interlocking unit 80 are rotated in the left movement rotation direction as in the case of assembly, so that the phases of the interlocking units 80 are aligned with each other as shown in FIG. In the state, the movement to the left (that is, the second crossing direction) can be started.

[3. Effect, etc.]
In the above configuration, the paper detection sensor unit 14 of the image forming apparatus 1 has a main body in which the upper sensor unit 70 is incorporated with the rotating unit 17 as the rotation center with respect to the lower body 15 in which the lower sensor unit 50 is incorporated. The upper portion 16 is configured to be rotatable (FIGS. 3 and 4).

Then, the paper detection sensor unit 14 causes the lower screw shaft 52 and the upper screw shaft 72 to rotate in conjunction with each other by the interlocking unit 80 (FIG. 4). Therefore, in the paper detection sensor unit 14, the upper carriage 75 and the lower carriage 55 can be interlocked and moved in the left-right direction regardless of the opening and closing of the upper body 16.

As a result, the paper detection sensor unit 14 can move the light emitting element 78 and the light receiving element 58 located opposite to each other with respect to the paper P by the same distance to the left or right, and the detection accuracy as a transmissive sensor can be improved. The detection position can be freely displaced to the left or right while maintaining the position.

Further, in the paper detection sensor unit 14, incomplete screw portions 52F and 72F are formed in the vicinity of the right ends of the lower screw shaft 52 and the upper screw shaft 72, and urging members 56 and 76 are further provided.

In the paper detection sensor unit 14, each part is assembled with the lower carriage 55 and the upper carriage 75 inserted through the incompletely threaded portions 52F and 72F, respectively, and then each gear of the interlocking portion 80 is moved to the left in the rotation direction. The lower carriage 55 and the upper carriage 75 are simultaneously started to move to the left (FIG. 7). As a result, the paper detection sensor unit 14 can be screwed into the screw portions 52S and 72S of the lower screw shaft 52 and the upper screw shaft 72, respectively, with the phases of the lower carriage 55 and the upper carriage 75 aligned. Can be moved to the left and right without breaking.

That is, in the paper detection sensor unit 14, the work of adjusting the rotation angles of the lower screw shaft 52 and the upper screw shaft 72 and the work of disassembling the interlocking unit 80 to temporarily release the interlocking of each gear for the operator. Alternatively, it is not necessary to perform work such as adjusting the position of each carriage using a dedicated jig. Therefore, the paper detection sensor unit 14 can align the phases of the lower carriage 55 and the upper carriage 75 with the operator extremely easily and in a short time.

In particular, in the paper detection sensor unit 14, in the lower screw shaft 52 and the upper screw shaft 72, the lengths of the incompletely threaded portions 52F and 72F in the left-right direction are set longer than the lengths in the left-right direction of the lower carriage 55 and the upper carriage 75. did. In addition, in the paper detection sensor unit 14, the lengths of the incompletely threaded portions 52F and 72F in the state where the urging members 56 and 76 are attached in the left-right direction are slightly smaller than the lengths in the left-right direction of the lower carriage 55 and the upper carriage 75. I set it short to.

As a result, in the paper detection sensor unit 14, the lower screw shaft 52 and the upper screw shaft 72 are simply rotated in the counterclockwise rotation direction, and the screw portions 52S and 72S are screwed into the inner grooves of the insertion holes 55H2 and 75H2 almost at the same time. It can be started and moved while maintaining the phases of the lower carriage 55 and the upper carriage 75. That is, the paper detection sensor unit 14 rotates the gear of the interlocking unit 80 in the left movement rotation direction without causing the operator to perform work such as urging the lower carriage 55 and the upper carriage 75 to the left. Just need it.

Further, in the paper detection sensor unit 14, even if the lower carriage 55 and the upper carriage 75 are out of phase due to maintenance work or the like, the lower carriage 55 can be simply rotated in the clockwise rotation direction by rotating each gear of the interlocking unit 80. And the upper carriage 75 can be sequentially reached to the incompletely threaded portions 52F and 72F near the right end (FIGS. 8 and 9). As a result, in the paper detection sensor unit 14, the phases of the lower carriage 55 and the upper carriage 75 can be aligned in the incompletely threaded portions 52F and 72F, so that each gear of the interlocking portion 80 is rotated in the counterclockwise rotation direction. Only by itself, the movement to the left can be started at the same time as in the case of manufacturing.

According to the above configuration, the paper detection sensor unit 14 has incompletely threaded portions 52F and 72F formed on the lower screw shaft 52 and the upper screw shaft 72, respectively (FIG. 5). Therefore, the paper detection sensor unit 14 simply rotates each gear of the interlocking unit 80 in the counterclockwise rotation direction with the lower carriage 55 and the upper carriage 75 inserted through the incompletely threaded portions 52F and 72F, respectively. Can be moved to the left while keeping the phases of the carriages aligned. As a result, the paper detection sensor unit 14 does not need to require the operator to perform troublesome work such as disassembly and position adjustment using a jig.

[4. Other embodiments]
In the above-described embodiment, the case where the incompletely threaded portions 52F and 72F are provided near the right ends of the lower screw shaft 52 and the upper screw shaft 72 has been described (FIG. 5 and the like). However, the present invention is not limited to this, and for example, the incompletely threaded portions 52F and 72F may be provided at other locations such as near the left end of the lower screw shaft 52 and the upper screw shaft 72.

Further, in the above-described embodiment, the case where the urging members 56 and 76 provided near the right ends of the lower screw shaft 52 and the upper screw shaft 72 are made of an elastic material such as rubber has been described. However, the present invention is not limited to this, and various other configurations may be used, for example, the urging members 56 and 76 may be springs made of a metal or resin material. Further, the urging members 56 and 76 may be omitted from the lower screw shaft 52 and the upper screw shaft 72.

Further, in the above-described embodiment, the left-right lengths of the incompletely threaded portions 52F and 72F of the lower screw shaft 52 and the upper screw shaft 72 are set based on the left-right lengths of the lower carriage 55 and the upper carriage 75. The case of determining (for example, lengthening) was described. However, the present invention is not limited to this, for example, in the insertion holes 55H2 and 75H2 in the lower carriage 55 and the upper carriage 75, when the range in which the inner groove is formed is shorter than the width in the left-right direction in the outer shape, the inner groove is formed. The lengths of the incompletely threaded portions 52F and 72F in the left-right direction may be determined based on the length of the formed range.

Further, in the above-described embodiment, the lower first regulation shaft 51 and the lower second regulation shaft 53 are inserted into the insertion holes 55H1 and 55H3 of the lower carriage 55, respectively, so that the lower carriage 55 can be moved in the front-rear direction and the vertical direction. The case where the position is determined and the rotation around the lower screw shaft 52 is suppressed has been described. However, the present invention is not limited to this, and for example, a rail along the left-right direction may be provided on the lower portion 15 of the main body, and an engaging body that engages with and slides on the lower carriage 55 may be provided. In short, it suffices if the rotation of the lower carriage 55 about the lower screw shaft 52 can be suppressed. The same applies to the upper carriage 75.

Further, in the above-described embodiment, the case where the operator rotates each gear of the interlocking unit 80 in the left movement rotation direction at the time of manufacturing to start the left movement of the lower carriage 55 and the upper carriage 75 has been described. However, the present invention is not limited to this, and for example, by supplying a driving force to each gear of the interlocking unit 80 from a motor (not shown) as a driving force supply unit and rotating the gear, the vehicle is rotated in the left movement rotation direction. The movement of the carriage 55 and the upper carriage 75 to the left may be started.

Further, during maintenance work, for example, when the maintenance work is completed and the power of the image forming apparatus 1 is turned on with the lower carriage 55 and the upper carriage 75 out of phase, the motor (not shown) is controlled by the control unit 5. ) May be driven to align the phases of the lower carriage 55 and the upper carriage 75. For example, the control unit 5 first rotates each gear of the interlocking unit 80 in the right movement rotation direction to position the lower carriage 55 and the upper carriage 75 near the right end, align the phases, and then rotate the lower carriage 55 and the upper carriage 75 in the right movement rotation direction. The lower carriage 55 and the upper carriage 75 may be moved to the left while keeping their phases aligned. Alternatively, by making such an operation a part of the initial operation immediately after the power is turned on, the phases of the lower carriage 55 and the upper carriage 75 may be aligned each time the power is turned on. Alternatively, for example, when the control unit 5 determines that the lower carriage 55 and the upper carriage 75 are out of phase based on the light receiving result by the light receiving element 58, that is, the receiving result, such an operation may be performed. good.

Further, in the above-described embodiment, when the lower portion 15 of the main body is manufactured, the lower first regulation shaft 51 and the lower second regulation shaft 53 and the incompletely threaded portion 52F of the lower screw shaft 52 inserted through the lower carriage 55 are attached to the left side plate. The case where the gears of the interlocking portion 80 are attached to the 15L and the right side plate 15R has been described. However, the present invention is not limited to this, for example, in a state where the right side plate 15R is removed from the lower part 15 of the main body, the lower first regulation shaft 51, the lower screw shaft 52, and the lower second regulation shaft 53 near the left end of the left side plate 15L. It may be assembled in various orders, such as inserting, incorporating each gear of the interlocking portion 80, further inserting the lower carriage 55, attaching the urging member 56, and then attaching the right side plate 15R. The same applies to the upper portion 16 of the main body.

Further, in the above-described embodiment, a case has been described in which the lower carriage 55 is assembled in a state of being inserted into the incompletely threaded portion 52F of the lower screw shaft 52 at the time of manufacturing the lower body portion 15 (FIG. 6). However, the present invention is not limited to this, and for example, when manufacturing the lower part 15 of the main body, the lower carriage 55 may be assembled in a state of being inserted at an arbitrary position in the threaded portion 52S of the lower screw shaft 52. In this case, by assembling the upper part 16 of the main body in the same manner, the same state as in FIG. 7 is obtained. Therefore, as in the case of the maintenance work described above, by rotating each gear of the interlocking portion 80 in the right movement rotation direction, The state shown in FIG. 6 can be obtained.

Further, in the above-described embodiment, the lengths of the lower carriage 55 and the upper carriage 75 in the left-right direction are aligned, and the lengths of the incompletely threaded portions 52F and 72F of the lower screw shaft 52 and the upper screw shaft 72 are also aligned in the left-right direction. The case has been described (FIGS. 7 and 8). However, the present invention is not limited to this, and for example, when the lengths of the lower carriage 55 and the upper carriage 75 in the left-right direction are different, the incompletely threaded portions 52F and 72F of the lower screw shaft 52 and the upper screw shaft 72 are in the left-right direction. The length may be different. In short, with the misalignment of the light emitting element 78 and the light receiving element 58 suppressed within an allowable range, screwing of the screw portions 52S and 72S with the thread grooves of the insertion holes 55H2 and 75H2 is started, respectively, and the lower carriage 55 It suffices if the upper carriage 75 can be started to move to the left.

Further, in the above-described embodiment, the case where the light emitting element 78 is provided on the upper carriage 75 and the light receiving element 58 is provided on the lower carriage 55 has been described (FIGS. 4 and 5). However, the present invention is not limited to this, and for example, the upper carriage 75 may be provided with the light receiving element 58, and the lower carriage 55 may be provided with the light emitting element 78. Alternatively, for example, the upper carriage 75 may be provided with a transmitting element for transmitting ultrasonic waves, and the lower carriage 55 may be provided with a receiving element for receiving the ultrasonic waves. In short, one of the upper carriage 75 and the lower carriage 55 may be provided with a transmitting element for transmitting various lights and electromagnetic waves, and the other may be provided with a receiving element for receiving the light and electromagnetic waves.

Further, in the above-described embodiment, a case where the paper P is a so-called label paper has been described (FIG. 2). However, the present invention is not limited to this, and the paper P may be a paper having various configurations. In this case, it is sufficient that the transmissive sensor composed of the light emitting element 78 and the light receiving element 58 can detect the position on the paper P where the image should be formed. Further, the paper P is not limited to long paper, and may be cut paper having a relatively short length such as A4 size.

Further, in the above-described embodiment, the case where the present invention is applied to the paper detection sensor unit 14 for detecting the position of the label paper piece PL in the image forming apparatus 1 for forming an image on the paper P made of label paper will be described. It was. However, the present invention is not limited to this, and various types of detecting the position of a medium such as paper by using a transmission type sensor such as a detection sensor group 34 (FIG. 1) provided in the central transport portion 23 of the main body portion 2. It may be applied to a sensor.

Furthermore, the present invention is not limited to each of the above-described embodiments and other embodiments. That is, the present invention has an applicable scope to an embodiment in which each of the above-described embodiments and a part or all of the above-mentioned other embodiments are arbitrarily combined, and an embodiment in which a part is extracted. Is.

Further, in the above-described embodiment, the main body lower portion 15 as the first main body portion, the main body upper portion 16 as the second main body portion, the rotating portion 17 as the main body rotating portion, and the lower portion as the first screw shaft. The screw shaft 52, the incompletely threaded portion 52F as the first alignment portion, the upper screw shaft 72 as the second screw shaft, the incompletely threaded portion 72F as the second aligning portion, and the first carriage. A paper detection sensor as a medium detection device by a lower carriage 55, an upper carriage 75 as a second carriage, a light emitting element 78 as a transmitting element, a light receiving element 58 as a receiving element, and an interlocking unit 80 as an interlocking unit. The case of forming the part 14 has been described. However, the present invention is not limited to this, and the first main body portion, the second main body portion, the main body rotating portion, the first screw shaft, the first alignment portion, and the second screw shaft having various other configurations are used. The medium detection device may be configured by the second alignment unit, the first carriage, the second carriage, the transmitting element, the receiving element, and the interlocking unit.

The present invention can be used, for example, in an image forming apparatus that detects the position of paper and forms an image according to the position.

1 ... Image forming device, 3 ... Transfer cutting unit, 4 ... Roll feeder unit, 5 ... Control unit, 12Y ... Transfer path, 14 ... Paper detection sensor unit, 15 ... Lower part of main body, 16 ... Upper body, 17 ... Rotating part, 18 ... Paper cutting part, 21 ... Primary transfer part, 50 ... Lower sensor part, 52 ... Lower screw shaft, 52F, 72F ... Incomplete screw part, 52S , 72S ... screw part, 55 ... lower carriage, 55H2, 75H2 ... insertion hole, 56, 76 ... urging member, 57 ... reflection sensor, 58 ... light receiving element, 70 ... upper sensor part, 72 …… Upper screw shaft, 75 …… Upper carriage, 78 …… Light emitting element, 80 …… Interlocking part, 82 …… Mediation gear, P …… Paper, PL …… Label paper piece.

Claims (7)

A first main body portion arranged on one side of a transport path for transporting a medium along a predetermined transport direction, and
The second main body portion arranged on the other surface side of the transport path and
A main body rotating portion that rotates the first main body portion with respect to the second main body portion about a central axis that is parallel to one surface and along an intersecting direction that intersects the transport direction.
A first screw shaft having a central axis along the crossing direction, rotatably supported around the central axis by the first main body portion, and having a thread groove formed on a peripheral side surface.
In the first screw shaft, a first alignment portion provided at an end portion on the first crossing direction side, which is one of the crossing directions, and the screw groove is omitted, and a first alignment portion.
A second screw shaft that has a central axis along the crossing direction and is rotatably supported around the central axis by the second main body portion and has a thread groove formed on the peripheral side surface.
A second alignment portion of the second screw shaft, which is provided at an end portion on the first crossing direction side and corresponds to the first alignment portion, and the screw groove is omitted.
It has a first insertion hole through which the first screw shaft is inserted, and a screw groove screwed with the screw groove of the first screw shaft is formed on the inner peripheral surface of the first insertion hole, and the first screw shaft has a screw groove. The first carriage that moves in the crossing direction as it rotates,
The second screw shaft has a second insertion hole through which the second screw shaft is inserted, and a screw groove screwed with the screw groove of the second screw shaft is formed on the inner peripheral surface of the second insertion hole. A second carriage that moves in the crossing direction as it rotates,
A transmitting element provided on one of the first carriage and the second carriage and transmitting light or electromagnetic waves to the transport path, and
A receiving element provided on the other side of the first carriage and the second carriage and receiving the light or the electromagnetic wave from the transport path, and
Through the intermediary rotary member which rotates about a common center axis and the body pivot portion, and the interlocking portion for interlocking the rotation of the rotary and the second screw shaft of the first screw shaft,
A driving force supply unit that supplies a driving force to the interlocking unit,
With a control unit that controls the driving force supply unit
With
The control unit supplies the driving force from the driving force supply unit to the interlocking unit, and rotates the first screw shaft and the second screw shaft, respectively, thereby causing the first carriage and the second carriage to move. After reaching the first alignment portion and the second alignment portion, the first screw shaft and the second screw shaft are rotated in opposite directions to form the first insertion hole in the first carriage. The screw groove is screwed with the screw groove of the first screw shaft, and the screw groove of the second insertion hole in the second carriage is screwed with the screw groove of the second screw shaft, and the first carriage and the said While keeping the phases of the second carriage aligned, they are moved in a direction away from the first alignment portion and the second alignment portion.
Medium detection device, characterized in that. The first screw shaft has the first alignment portion in a range longer than the length of the range in which the thread groove of the first insertion hole in the first carriage is formed at the end portion on the first crossing direction side. Is formed,
The second screw shaft has a second alignment portion that is longer than the length of the range in which the thread groove of the second insertion hole in the second carriage is formed at the end portion on the first crossing direction side. The medium detection device according to claim 1, wherein the medium is formed. A first urging portion that urges the first carriage in a second crossing direction opposite to the first crossing direction.
The medium detection device according to claim 1 or 2, further comprising a second urging portion for urging the second carriage in the second crossing direction. The pitch of the thread grooves in the first screw shaft and the second screw shaft is displaced with respect to the crossing direction of the receiving element and the transmitting element so that the receiving element can receive the light or the electromagnetic wave from the transmitting element. The medium detection device according to claim 2, wherein the medium detection device is smaller than the range of. When the control unit determines that the transmitting element is displaced with respect to the receiving element in the crossing direction based on the reception result of the light or the electromagnetic wave by the receiving element, the driving force supply unit The medium detection device according to claim 1 , wherein a driving force is supplied to the interlocking portion. The medium detection device according to claim 1 , wherein the control unit supplies a driving force from the driving force supply unit to the interlocking unit each time a power is turned on. The medium detection device according to any one of claims 1 to 6 .
Comprising an image forming unit for fixing by transferring an image formed by the current image agent,
The control unit determines the position of the medium based on the reception result of the light or the electromagnetic wave by the receiving element, and determines the position of the medium.
The image forming unit transfers and fixes the image in accordance with the position of the medium determined by the control unit.
Image forming apparatus characterized by.

Images