JP2021014317A - Belt conveyance control device - Google Patents

Abstract

To improve product quality and yielding percentage of inkjet printing.SOLUTION: A belt conveyance control device 30 includes: an idler 31 placed on the front side in a front-rear direction LD with the axis in a left-right direction; second toothed pulleys 32a, 32b arranged on the rear side in the front-rear direction LD with the axis in the left-right direction; a timing belt 33a wound around the idler 31 and the second toothed pulley 32a and a timing belt 33b wound around the idler 31 and the second toothed pulley 32b; and a top plate 34 placed between the idler 31 and the second toothed pulleys 32a, 32b. An upper surface of the top plate 34 has a convex curved surface, and the timing belts 33a, 33b move inside each of two guide grooves formed on the upper surface of the top plate 34. When the belt transfer control device 30 is installed in a printing device 1, a back surface of a transfer belt 5 provided in the printing device 1 and back surfaces of the timing belts 33a, 33b come into surface contact with each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a belt transfer control device, and can be suitably applied to, for example, a belt transfer control device for controlling the transfer of a belt provided in an inkjet printing device.

For example, Japanese Patent Application Laid-Open No. 8-156353 (Patent Document 1) provides a lower platen roller at a position facing the upper platen roller and applies tension to the belt to displace the upper platen roller and displace the belt of the printer unit. A belt transfer that can reduce the change in tension acting on the belt even when the gap between the belt and the inkjet head is adjusted is described.

Further, in Japanese Patent Application Laid-Open No. 2017-065063 (Patent Document 2), the inkjet head is arranged on the upstream side and the downstream side of the inkjet head on the opposite sides of the inkjet head and the web, respectively, to support the web. A device for providing an inkjet printing device including a pair of platen rollers that drive the web together and a timing belt that rotates the pair of platen rollers synchronously is described.

Japanese Unexamined Patent Publication No. 8-156353 Japanese Unexamined Patent Publication No. 2017-065063

In the inkjet printing device, by attaching an encoder to the rotation mechanism of the existing conveyor belt, the movement amount of the conveyor belt is recognized and printing on a printing medium is possible. However, when slip occurs in the transport belt, the synchronization between the information obtained from the encoder and the actual movement amount of the transport belt is impaired, and the landing accuracy of the ink droplets deteriorates. Further, when vibration is generated in the transport belt due to a change in tension or the like, there is a problem that the reproducibility of printing is remarkably lowered.
Other challenges and novel features will become apparent from the description and accompanying drawings herein.

The belt transport control device according to the embodiment is arranged on the front side in the front-rear direction with the axis in the left-right direction, and the idler composed of the first toothed pulley and the connecting shaft and the axis in the left-right direction. The second toothed pulley is arranged on the rear side in the front-rear direction, the timing belt wound around the first toothed pulley and the second toothed pulley, and the idler and the second toothed pulley. It is equipped with a top plate. The upper surface of the top plate has a convex curved surface, and a guide groove is formed on the upper surface of the top plate so that the timing belt moves inside the top plate along the front-rear direction. When a belt transfer control device is installed in an inkjet printing device, the back surface of the transfer belt provided in the inkjet printing device and the back surface on the opposite side of the tooth surface of the timing belt come into surface contact, and the linear motion of the transfer belt is caused by the linear motion of the timing belt. It is transmitted to the linear motion and converted into the rotational motion of the timing belt.

According to one embodiment, the quality and yield of products in inkjet printing can be improved.
A brief description of the effects obtained by representative of the inventions disclosed in the present application is as follows.

It is a schematic side view which shows the whole structure of the inkjet printing apparatus to which the belt transport control apparatus by embodiment is applied. It is a schematic top view which shows the whole structure of the inkjet printing apparatus to which the belt transport control apparatus by embodiment is applied. (A) and (b) are a schematic side view and a schematic top view showing the overall configuration of the belt transport control device according to the embodiment, respectively. It is a top view of the top plate provided in the belt transport control device according to the embodiment. It is sectional drawing along the line AA'shown in FIG. 3 (b). It is a schematic side view which shows the whole structure of the inkjet printing apparatus to which the belt transport control apparatus by the modification of embodiment is applied. It is a schematic top view which shows the whole structure of the inkjet printing apparatus to which the belt transport control apparatus by the modification of embodiment is applied. It is a schematic side view which shows the whole structure of the inkjet printing apparatus which the present inventor compared and examined.

Hereinafter, embodiments will be described in detail with reference to the drawings. In all the drawings for explaining the embodiment, members having the same function are designated by the same or related reference numerals, and the repeated description thereof will be omitted. In addition, when a plurality of similar members (parts) exist, a symbol may be added to the generic code to indicate an individual or a specific part. Further, in the following embodiments, the description of the same or similar parts is not repeated in principle except when it is particularly necessary.

Further, in the drawings used in the embodiment, hatching may be omitted in order to make the drawings easier to see even if they are cross-sectional views. Further, even if it is a plan view, hatching may be added to make the drawing easier to see.

Further, in the cross-sectional view and the plan view, the size of each part does not correspond to the actual device, and a specific part may be displayed relatively large in order to make the drawing easy to understand. Further, even when the cross-sectional view and the plan view correspond to each other, a specific part may be displayed in a relatively large size in order to make the drawing easy to understand.

Further, in the following embodiments, the F direction indicated by the arrow F, the R direction indicated by the arrow R, and the T direction indicated by the arrow T are used as explanatory directions. The F direction is a direction indicating the front, the R direction is a direction indicating the right side, and the T direction is a direction indicating an upward direction, and the position or direction of each part is based on the front direction, the right side, and the upper side. In addition, the front may be referred to as upstream and the rear may be referred to as downstream.

Further, in the following embodiments, the left-right direction (first direction) and the front-back direction (second direction) are used as explanatory directions, but the left-right direction and the front-back direction are orthogonal to each other to form a horizontal plane. The direction.
(An inkjet printing device that the present inventor has compared and examined)

First, since it seems that the belt transfer control device according to the embodiment of the present invention will become clearer, FIG. 8 is used to discuss the problems in the inkjet printing device before the application of the present invention, which was compared and examined by the present inventor. This will be described below. FIG. 8 is a schematic side view showing the overall configuration of the inkjet printing apparatus that the present inventor has compared and examined. Note that FIG. 8 is a schematic configuration diagram of a left side view of the inkjet printing apparatus as viewed from the left side.

As shown in FIG. 8, the printing device 51 is an inkjet printing device that performs printing work by ejecting edible ink onto the upper surface of food 54 such as rice crackers, which is a printing medium.

The printing device 51 has a printing processing unit 52 that ejects edible ink onto the upper surface of the food 54 to print characters and the like, and puts the food 54 on the surface of the transport belt 55 to print the food 54 to just below the printing processing unit 52. It is provided with a belt transport unit 53 for transporting. The transport belt 55 rotates clockwise on the rotating surface viewed from the left side.

The print processing unit 52 includes a head unit 56, a print control unit 57, a print unit 58 to which the head unit 56 and the print control unit 57 are attached, a control unit 59, and a maintenance unit 60.

The head unit 56 has an inkjet head (not shown) formed in a nozzle for ejecting edible ink at substantially the center of the LD in the front-rear direction of the belt transport unit 53. The print control unit 57 supplies the edible ink to the inkjet head. The control unit 59 supplies the edible ink to the head unit 56 and the print control unit 57 based on various signals, and controls the driving power for discharging the edible ink. The maintenance unit 60 performs maintenance work such as head cleaning on the head unit 56.

The belt transport unit 53 is provided with a belt transport unit frame (not shown), and the belt transport unit 55 rotates so as to sandwich the upper and lower sides of the belt transport unit frame. The printing processing unit 52 is installed on the upper surface side of the belt transport unit frame, and the drive unit of the belt transport unit 53 is installed on the lower surface side of the belt transport unit frame.

Further, in the belt transport unit 53, an inlet roller 61 and an outlet roller 62 are arranged on the front side and the rear side, respectively, with the print processing unit 52 in between. Further, on the drive unit side of the belt transport unit 53, the first idler roller 63 and the second idler roller 64 are arranged in the middle between the input roller 61 and the output roller 62, and the first idler roller 63 and the second idler roller 64 are arranged. A drive roller 65 and a tension roller 66 are arranged in the middle of the space between the idler roller 64 and the idler roller 64. All of these rollers 61 to 66 are axially supported with their axial centers oriented in the left-right direction, and the conveyor belt 55 is wound around these rollers 61 to 66. The shaft support means that the shaft is rotatably supported.

A rotary encoder 67 is installed on the output roller 62. By detecting information such as the rotation direction, movement position, and movement speed of the transfer belt 55 from the rotary encoder 67, the movement of the transfer belt 55 can be controlled with high accuracy.

However, if slip occurs between the transport belt 55 and the output roller 62, the synchronization between the information obtained from the rotary encoder 67 and the actual movement amount of the transport belt 55 may be impaired. In this case, for example, food. There arises a problem that the landing accuracy of the ink droplets on the 54 or the printing resolution is lowered.

Further, the transport belt 55 for food is generally made of a soft material such as polyurethane and has elasticity. For this reason, sudden expansion and contraction due to external causes, periodic expansion and contraction due to a long circumference, lateral vibration, etc. due to changes in tension occur in the transport belt 55, and the reproducibility of printing on the food 54 is improved. There is also the problem that it drops significantly.
(Embodiment)
≪Configuration of inkjet printing device≫

The inkjet printing apparatus according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic side view showing the overall configuration of an inkjet printing device to which the belt transfer control device according to the present embodiment is applied. FIG. 2 is a schematic top view showing the overall configuration of an inkjet printing device to which the belt transfer control device according to the present embodiment is applied. Note that FIG. 1 is a schematic configuration diagram of a left side view of the inkjet printing apparatus as viewed from the left side.

As shown in FIGS. 1 and 2, the printing device 1 ejects edible ink onto the upper surface of a food product 4 such as a senbei, which is a printing medium, in which a belt transport unit 3 which is a belt type transport device is incorporated. It is an inkjet printing device that performs printing work. The usage pattern of the belt transport unit 3 here is only an example, and is not particularly limited to this mode.

The printing device 1 prints by placing the food 4 on the surface of the printing processing unit 2 that ejects edible ink onto the upper surface of the food 4 that is the printing medium to print characters and the like, and the transport belt 5 in the form of an endless belt. It is provided with a belt transport unit 3 that transports the food 4 to just below the portion 2. The transport belt 5 rotates clockwise on the rotating surface viewed from the left side. The width of the horizontal (first direction) HD of the transport belt 5 is about 2 to 3 times the size of the food 4, for example, about 100 to 200 mm. The transport belt 5 is made of a soft material such as polyurethane.

The print processing unit 2 is composed of a head unit 6, a print control unit 7, a print unit 8 to which the head unit 6 and the print control unit 7 are attached, a control unit 9, and a maintenance unit 10.

The head unit 6 has a plurality of inkjet heads 11 which are located substantially in the center of the LD in the front-rear direction (second direction) of the belt transport unit 3 and have nozzles for ejecting edible ink. The print control unit 7 supplies the edible ink to the inkjet head 11. The control unit 9 supplies the edible ink to the head unit 6 and the print control unit 7 based on various signals, and controls the driving power for discharging the edible ink. The maintenance unit 10 performs maintenance work such as head cleaning on the head unit 6.

The belt transport unit 3 is provided with a belt transport unit frame 21, and the belt transport unit 5 rotates so as to sandwich the upper and lower sides of the belt transport unit frame 21. The printing processing unit 2 is installed on the upper surface side of the belt transport unit frame 21, and the drive unit of the belt transport unit 3 is installed on the lower surface side of the belt transport unit frame 21.

Further, the belt transport unit 3 has an inlet roller (also referred to as a tail roller and a tail pulley) 12 and an outlet roller (also referred to as a tail roller and a tail pulley) on the front side (upstream side) and the rear side (downstream side) with the print processing unit 2 sandwiched between them. (Also referred to as a tail roller and a tail pulley.) 13 is pivotally supported with the axis centered in the left-right direction HD. That is, the inlet roller 12 and the outlet roller 13 are axially supported on the front side and the rear side of the belt transport portion frame 21, respectively, with the axis centered in the left-right direction HD.

On the upper surface side of the belt transport unit frame 21, a belt transport control device 30 having a rotation mechanism is installed between the upper surface of the belt transport unit frame 21 and the transport belt 5. The belt transfer control device 30 is removable from the printing device 1, and has an idler 31 and two second-toothed pulleys 32a and 32b arranged on the front side and the rear side, respectively, and an idler 31 and a second-toothed pulley 32a. It is composed of a timing belt 33a in the form of an endless belt wound around the idler 31 and a timing belt 33b in the form of an endless belt wound around an idler 31 and a pulley 32b with a second tooth (see FIG. 3B).

The back surface of the transport belt 5 (the surface opposite to the surface on which the food 4 is placed) and the back surfaces of the two timing belts 33a and 33b (the surface opposite to the tooth surface) are in surface contact with each other, and the transport belt 5 is LD in the front-rear direction. The linear motion of the two timing belts 33a and 33b is transmitted to the motion of the LD in the front-rear direction. The idler 31 and the two second-toothed pulleys 32a and 32b are pivotally supported with the axial center set to HD in the left-right direction. The 32a rotates, and the idler 31 and the pulley 32b with the second tooth rotate via the timing belt 33b.
The details of the configuration of the belt transfer control device 30 will be described in << Belt transfer control device >> described later.

On the lower surface side of the belt transport portion frame 21, the first idler roller 14 and the second idler roller 15 are arranged in the middle between the inlet roller 12 and the outlet roller 13 to support the shaft with the axis centered in the left-right direction HD. A drive roller 16 is pivotally supported in the middle of the space between the first idler roller 14 and the second idler roller 15 with the axis centered in the left-right direction HD. Further, a tension roller 17 is pivotally supported in the middle between the first idler roller 14 and the drive roller 16 on the front side with the axis centered in the left-right direction HD. All of these rollers 12 to 17 are rotatably supported by shafts, and a conveyor belt 5 is wound around these rollers 12 to 17.

Further, a tension unit 20 composed of a tension roller 17, a tension frame 18, and a tension spring 19 is formed from the first idler roller 14 on the front side to the tension roller 17. The tension roller 17 is pivotally supported by a tension frame 18 that can swing back and forth around the axis of the first idler roller 14 on the front side, and the rear end of the tension frame 18 is elastic downward via the tension spring 19. Is being towed. As a result, the portion of the transport belt 5 that is wound from the lower surface of the outer circumference of the drive roller 16 to the rear surface of the outer circumference of the first idler roller 14 can be pressed from behind by the front surface of the outer circumference of the tension roller 17, so that the transport belt 5 is predetermined. Tension can be constantly applied, loosening of the transport belt 5 can be reduced, and slippage and the like can be suppressed.

Further, a rotary encoder 22 is installed on the outlet roller 13 arranged in the belt transport unit 3. By detecting information such as the rotation direction, movement position, and movement speed of the transfer belt 5 from the rotary encoder 22, the movement of the transfer belt 5 can be controlled with high accuracy. The rotary encoder 22 is not particularly limited, but is, for example, a standard optical transmission encoder, which is composed of a light emitting element, a lens, a cord wheel, a light receiving element, and the like. In the present embodiment, the rotary encoder 22 is installed on the axis of the outlet roller 13, and the light passing through the slit of the chord wheel is transmitted to the photodiode on the light receiving element and processed by the signal conversion circuit unit. It is output to the encoder as two square waves. By processing the encoder output, it is possible to detect information such as the rotation direction, the moving position, and the moving speed of the transport belt 5.

In the present embodiment, the rotary encoder 22 is installed on the outlet roller 13, but the present invention is not limited to this, and the rotary encoder 22 may be installed on the inlet roller 12. Further, for example, an encoder may be provided at a position immediately before the print processing unit 2.

Further, a camera 23 is installed above the transport belt 5 at a position immediately before the printing processing unit 2 as a position sensor for detecting the position of HD in the left-right direction of the food 4. Further, a food detection sensor 24 capable of transmitting and receiving light or sound waves is installed on the front side of the camera 23. The food detection sensor 24 is composed of, for example, a floodlight 24a and a light receiver 24b attached by sandwiching the transport belt 5 in the left-right direction HD, and the food 4 conveyed by the transport belt 5 is the floodlight 24a and the light receiver 24b. By blocking the light by passing through the space, the position of the LD in the front-rear direction, which is the transport direction of the food 4, can be detected.

From the image obtained by the camera 23, the positions of the food 4 in the front-rear direction LD and the left-right direction HD on the transport belt 5 can be obtained, and the amount of deviation from the center of the left-right direction HD can be obtained based on the signal. Centering control can be performed. Further, after a predetermined time has elapsed after the food detection sensor 24 detects the passage of the food 4, it is considered that the food 4 has reached the lower part of the head unit 6, and the edible ink is transferred from the head unit 6 onto the passing food 4. The printing process can be performed by ejecting ink droplets.
≪Belt transport control device≫

Next, the details of the configuration of the belt transfer control device will be described with reference to FIGS. 3 (a) and 3 (b), FIGS. 4 and 5. 3A and 3B are a schematic side view and a schematic top view showing the overall configuration of the belt transfer control device according to the present embodiment, respectively. FIG. 4 is a top view of a top plate provided in the belt transport control device according to the present embodiment. FIG. 5 is a cross-sectional view taken along the line AA'shown in FIG. 3 (b).

As described above, the printing device 1 has a removable belt transport control device 30 on the back surface side of the transport belt 5 which is substantially in the center of the front-rear direction LD of the belt transport unit 3 and faces the printing processing unit 2. is set up.

As shown in FIGS. 3A and 3B, the belt transport control device 30 is arranged side by side in the left-right direction HD on the rear side (downstream side) and the idler 31 arranged on the front side (upstream side). It is provided with two second-toothed pulleys 32a and 32b. The idler 31 and the two pulleys 32a and 32b with the second teeth are arranged so that their axes are HD in the left-right direction. Further, the distance between the axial center of the idler 31 and the axial centers of the two pulleys 32a and 32b with the second teeth in the front-rear direction LD is kept constant, for example, about 400 mm.

The idler 31 is composed of two first-toothed pulleys 31a and 31b arranged side by side in the left-right direction HD and a connecting shaft 31b connecting the axes of the two first-toothed pulleys 31a and 31b. .. A timing belt 33a in the form of an endless belt is wound around a pulley 31a with a first tooth provided on the idler 31 on the front side and a pulley 32a with a second tooth on the rear side. Similarly, a timing belt 33b in the form of an endless belt is wound around a pulley 31b with a first tooth provided on the idler 31 on the front side and a pulley 32b with a second tooth on the rear side.

Further, a rotary encoder 36 is installed in the idler 31. By detecting information such as the rotation direction, movement position, and movement speed of the timing belts 33a and 33b from the rotary encoder 36, the movement of the timing belts 33a and 33b can be controlled with high accuracy. The rotary encoder 36 is not particularly limited, but like the rotary encoder 22 described above, it is, for example, a standard optical transmission encoder, and is composed of a light emitting element, a lens, a cord wheel, a light receiving element, and the like. Will be done.

In the present embodiment, the rotary encoder 22 is installed in the output loader 13 provided in the belt transport unit 3 of the printing device 1 (see FIG. 1), and the rotary encoder 36 is mounted in the idler 31 provided in the belt transport control device 30. Although it was installed, a rotary encoder may be installed on either side. That is, any one of the three modes in which the rotary encoder is installed in the output loader 13, the idler 31, or the output loader 13 and the idler 31 may be used.

The timing belts 33a and 33b have a tooth surface on which convex belt teeth are formed and a smooth back surface on the side opposite to the tooth surface, so that the inner peripheral side is the tooth surface and the outer peripheral side is the back surface. It is wound around the idler 31 and the pulleys 32a and 32b with the second teeth. That is, the timing belt 33a is attached by aligning the belt teeth of the timing belt 33a with the groove of the first toothed pulley 31a provided on the front idler 31 and the groove of the second toothed pulley 32a on the rear side. Similarly, the timing belt 33b is attached by aligning the belt teeth of the timing belt 33b with the groove of the first toothed pulley 31b provided on the front idler 31 and the groove of the second toothed pulley 32b on the rear side.

As a result, when the belt transport control device 30 is installed in the printing device 1, the back surfaces of the timing belts 33a and 33b come into surface contact with the back surface of the transport belt 5, and the linear motion of the transport belt 5 in the front-rear direction LD is caused by the timing belt 33a. , 33b is transmitted to the linear motion of the front-back LD. At this time, the belt transfer control device 30 is a mechanism independent of the printing device 1, and the timing belts 33a and 33b are not easily affected by the expansion and contraction of the transfer belt 5, so that the reproducibility is good and the linear motion of the transfer belt 5 is timed. It is transmitted to the linear motion of the belts 33 and 33b, and is further converted into a rotary motion. Then, by the operation of the transport belt 5, the idler 31 and the pulley 32a with the second tooth rotate via the timing belt 33a, and the idler 31 and the pulley 32b with the second tooth rotate via the timing belt 33b to reach the idler 31. Information on the rotational motion is output to the installed rotary encoder 36.

In this way, the back surfaces of the timing belts 33a and 33b are brought into surface contact with the back surface of the transport belt 5 to move the transport belt 5, so that the friction generated between the two causes slip, expansion and contraction, lateral vibration, and the like of the transport belt 5. It can be reduced.

As shown in FIGS. 3A and 3B and FIG. 4, the space between the idler 31 and the pulleys 32a and 32b with the second teeth (inside the wound timing belts 33a and 33b) is made of resin. The top plate 34 is installed. The upper surface of the top plate 34 has a convex curved surface with a protruding central portion when viewed from the left side. The radius of curvature of the upper surface of the top plate 34 in the left side view is, for example, about 4,000 to 5,000, and the upper surface of the top plate 34 forms a gentle curve in the left side view. As a result, the contact area between the back surface of the transport belt 5 and the back surfaces of the timing belts 33a and 33b can be increased, and the initial load can be applied. Therefore, the slippage of the transport belt 5 from the timing belts 33a and 33b can be suppressed to a small value. Can be done.

The thickness of the central portion may be made larger than the thickness of the front end portion and the rear end portion to form a convex curved surface in the T direction only on the upper surface of the top plate 34, or the entire thickness may be uniform. As a result, a convex curved surface in the T direction may be formed on the upper surface of the top plate 34, and a concave curved surface in the T direction may be formed on the lower surface.

Further, two guide grooves 35a and 35b having a constant depth are formed on the upper surface of the top plate 34 along the front-rear direction LD. The timing belt 33a moves inside the one guide groove 35a, and the timing belt 33b moves inside the other guide groove 35b. In the present embodiment, two guide grooves 35a and 35b are illustrated, but the present invention is not limited to this, and the number of guide grooves is 1 or more and 5 or less according to the width of the transport belt 5. May be. That is, the number of timing belts may be 1 or more and 5 or less. At this time, the number of pulleys with first teeth and the number of pulleys with second teeth provided in the idler 31 are also adjusted according to the number of guide grooves or the number of timing belts.

As shown in FIG. 5, the width of the guide groove 35a in the left-right direction HD is set to be slightly larger than the width of the timing belt 33a so that the timing belt 33a can move inside the guide groove 35a. Similarly, the width of the guide groove 35b in the left-right direction HD is set to be slightly larger than the width of the timing belt 33b so that the timing belt 33b can move inside the guide groove 35b. For example, assuming that the widths of the timing belts 33a and 33b are W1 and the widths of the guide grooves 35a and 35b in the left-right direction HD are W2, the widths W2 of the guide grooves 35a and 35b are preferably in the range of W1 <W2 ≦ (W1 + 1.0 mm). .. In the present embodiment, the width W1 of the timing belts 33a and 33b is 10 mm, and the width W2 of the guide grooves 35a and 35b in the left-right direction HD is 11 mm.

In the present embodiment, the width of the timing belt 33a and the width of the timing belt 33b are the same, but the width is not limited to this and may be different from each other.

Further, as shown in FIG. 5, the depths of the guide grooves 35a and 35b are set to be smaller than the thickness of the upper surface and the back surface of the belt teeth on the tooth surfaces of the timing belts 33a and 33b, and are inside the guide grooves 35a and 35b. When the timing belts 33a and 33b are installed in the above, the back surface of the timing belts 33a and 33b protrudes from the upper surface 34a of the top plate 34 by, for example, about 0.5 mm to 1.0 mm. In other words, a gap of, for example, about 0.5 mm to 1.0 mm is formed between the upper surface 34a of the top plate 34 on which the guide grooves 35a and 35b are not formed and the back surface 5a of the transport belt 5. As a result, on the upper surface 34a side of the top plate 34, the back surface 5a of the transfer belt 5 and the back surfaces of the timing belts 33a and 33b are in surface contact with each other, but the back surface 5a of the transfer belt 5 and the guide grooves 35a and 35b are not formed. It does not come into contact with the upper surface 34a of the top plate 34.

Further, as described above, since the upper surface 34a of the top plate 34 has a convex curved surface, the transport belt 5 has bending resistance in a certain direction, so that the guide grooves 35a and 35b Even when the timing belts 33a and 33b move inside, an appropriate gap can be maintained between the upper surface of the top plate 34 on which the guide grooves 35a and 35b are not formed and the back surface 5a of the transport belt 5. As a result, the contact between the upper surface 34a of the top plate 34 on which the guide grooves 35a and 35b are not formed and the back surface 5a of the transfer belt 5 is substantially eliminated, so that the wear of the transfer belt 5 is significantly reduced. As a result, vibration of the transport belt 5 due to wear and wear of the transport belt 5 and the top plate 34 can be prevented.

In the present embodiment, the belt transport control device 30 is installed at substantially the center of the front-rear direction LD of the belt transport unit 3, but is installed at a position deviated from the center in relation to the installation position of the print processing unit 2. May be good.

Further, in the present embodiment, the depths of the guide grooves 35a and 35b formed in the top plate 34 of the belt transport control device 30 are constant, but the depth is not limited to this, and the ceiling is not limited to this. Even if the guide grooves 35a and 35b in which the depth of the central portion of the plate 34 is shallower than the depth of the end portion or the guide grooves 35a and 35b in which the depth of the central portion of the top plate 34 is deeper than the depth of the end portion are formed. Good.

Further, in the present embodiment, the idler 31 of the belt transport control device 30 does not include a drive mechanism, but may include a drive mechanism. If the idler 31 is provided with a drive mechanism so that the timing belts 33a and 33b can move linearly in synchronization with the linear motion of the transport belt 5, for example, slippage and vibration of the transport belt 5 can be further reduced.

As described above, according to the present embodiment, the belt transfer control device 30 is installed between the belt transfer unit frame 21 provided in the printing device 1 and the transfer belt 5, and the belt transfer control device is placed on the back surface of the transfer belt 5. By moving the transport belt 5 by bringing the back surfaces of the timing belts 33a and 33b provided in the 30 into surface contact with each other, it is possible to reduce vibration caused by slippage and tension change of the transport belt 5 due to friction generated between the two. it can. Since the slip of the transport belt 5 can be reduced, the accuracy of the ink droplets landing on the food 4 can be improved. Further, since the vibration of the transport belt 5 can be reduced, the deterioration of the reproducibility of printing on the food 4 can be suppressed. As a result, the quality and yield of products in inkjet printing can be improved.

Further, since the belt transfer control device 30 is a mechanism independent of the printing device 1 and is only attached to the existing printing device 1, the installation work of the belt transfer control device 30 is easy, and the transfer belt 5 of the printing device 1 Since the adjustment can be simplified, the belt transfer control device 30 can be installed in a short time.
(Modification example)
≪Configuration of inkjet printing device≫

The inkjet printing apparatus according to the modified example of this embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a schematic side view showing an overall configuration of an inkjet printing device to which a belt transfer control device according to a modified example of the present embodiment is applied. FIG. 7 is a schematic top view showing the overall configuration of an inkjet printing device to which the belt transfer control device according to the modified example of the present embodiment is applied. Note that FIG. 6 is a schematic configuration diagram of a left side view of the inkjet printing apparatus as viewed from the left side.

As shown in FIGS. 6 and 7, the printing device 1A is mounted on the upper surface of a food product 4 such as a senbei, which is a printing medium, in which a printing processing unit 2 and a belt transporting unit 3 are incorporated, as in the printing device 1 described above. This is an inkjet printing device that ejects edible ink to perform printing work. Further, a belt transfer control device 30 having a rotation mechanism is installed between the upper surface of the belt transfer unit frame 21 and the transfer belt 5.

The modified example differs from the above-described embodiment in that the hold roller 37 is installed on the surface side of the transport belt 5. Since the other configurations are the same as or substantially the same as those of the printing apparatus 1 described above, the description thereof will be omitted.

A hold roller 37 is axially supported on the front side (upstream side) and the rear side (downstream side) of the belt transfer control device 30 and on the surface side of the transfer belt 5 with the axis centered in the left-right direction HD. .. By suppressing the end of the transfer belt 5 in the left-right direction HD by the hold roller 37, it is possible to prevent the transfer belt 5 from floating and slipping.

Further, in the printing device 1 described above, the belt transfer control device 30 is installed in order to reduce the slip and vibration of the transfer belt 5. However, at the end of the belt transfer control device 30 in the front-rear direction LD, the transfer belt 5 may float and the contact area between the back surface of the transport belt 5 and the upper surfaces of the timing belts 33a and 33b may be reduced. In particular, when the transport belt 5 is used for a long time, the transport belt 5 may stretch, so that there is a concern that the contact area may be reduced. However, by installing the hold roller 37, the back surface of the transport belt 5 and the back surfaces of the timing belts 33a and 33b come into surface contact with each other even at the end of the LD in the front-rear direction of the belt transport control device 30, and the contact area between the two Can be secured.

As described above, according to the modified example, by holding the surface side of the transport belt 5 with the hold roller 37, the transport belt 5 floats, and in particular, the transport belt 5 at the end of the front-rear LD of the belt transport control device 30. It is possible to suppress the floating and prevent the reduction of the contact area between the back surface of the transport belt 5 and the back surfaces of the timing belts 33a and 33b. Thereby, it is possible to obtain a higher effect of reducing slip and vibration of the transport belt 5.

Although the invention made by the present inventor has been specifically described above based on the embodiment, the present invention is not limited to the embodiment and can be variously modified without departing from the gist thereof. Needless to say.

1,1A Printing equipment 2 Printing processing unit 3 Belt transport unit 4 Food 5 Conveyance belt 5a Back side 6 Head unit 7 Printing control unit 8 Printing unit 9 Control unit 10 Maintenance unit 11 Inkjet head 12 Inlet roller 13 Outlet roller 14 First idler roller 15 Second idler roller 16 Drive roller 17 Tension roller 18 Tension frame 19 Tension spring 20 Tension unit 21 Belt transfer frame 22 Rotating encoder 23 Camera 24 Food detection sensor 24a Floodlight 24b Receiver 30 Belt transfer control device 31 Idler 31a, 31b First toothed pulley 31c Connecting shafts 32a, 32b Second toothed pulleys 33a, 33b Timing belt 34 Top plate 34a Top surface 35a, 35b Guide groove 36 Rotary encoder 37 Hold roller 51 Printing device 52 Printing processing unit 53 Belt transport unit 54 Food 55 Conveyance belt 56 Head unit 57 Printing control unit 58 Printing unit 59 Control unit 60 Maintenance unit 61 Input roller 62 Outlet roller 63 1st idler roller 64 2nd idler roller 65 Drive roller 66 Tension roller 67 Rotating encoder HD Left / right direction ( 1st direction)
LD front-back direction (second direction)

Claims (8)

It is composed of a pulley with a first tooth and a connecting shaft attached to the axis of the pulley with the first tooth, which is arranged on the upstream side in the second direction orthogonal to the first direction with the axis in the first direction. With the idler
A second toothed pulley arranged on the downstream side of the second direction with the axis in the first direction,
A timing belt having a tooth surface wound around the first toothed pulley and the second toothed pulley and having belt teeth formed on one surface thereof.
A top plate arranged between the idler and the second toothed pulley,
With
A guide groove is formed on the upper surface of the top plate so that the timing belt moves inside the top plate along the second direction, and the depth of the guide groove is the depth of the tooth surface of the timing belt. A belt transport control device having a thickness smaller than the thickness of the upper surface of the belt tooth and the back surface opposite to the tooth surface. The belt transport control device according to claim 1.
A belt transport control device in which the upper surface of the top plate has a convex curved surface, and the radius of curvature of the curved surface of the top plate is 4,000 to 5,000. The belt transport control device according to claim 1.
A belt transport control device in which the height difference between the upper surface of the top plate on which the guide groove is not formed and the back surface of the timing belt is 0.5 mm to 1.0 mm. The belt transport control device according to claim 1.
A belt transport control device in which the width of the guide groove in the first direction is larger than the width W1 of the timing belt in the first direction and is (W1 + 1.0 mm) or less. The belt transport control device according to claim 1.
A belt transfer control device including an encoder at one end of the connecting shaft constituting the idler. The belt transport control device according to claim 1.
A belt transfer control device in which the number of timing belts is 1 or more and 5 or less.
Said The belt transport control device according to claim 1.
The printing apparatus is installed so that one surface of the printing conveyor belt provided in the printing apparatus comes into surface contact with the back surface of the timing belt, and the linear motion of the printing conveyor belt becomes the linear motion of the timing belt. A belt transfer control device that is transmitted. The belt transport control device according to claim 7.
A belt transfer control device further provided with hold rollers on the upstream side of the idler and the downstream side of the second toothed pulley so as to press the other surface of the printing transfer belt.