JP2017024244A - Automatic screen printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic screen printing device that can perform pressure adjustment with high accuracy while performing switch of squeegees used in printing and pressing force adjustment with a simple structure.SOLUTION: An automatic screen printing device 1 includes: a screen 4 arranged along a surface of an object C to be printed; squeegee carriers 20, 20 reciprocating along the screen; and a pair of squeegees 30A, 30B for forward movement which print on the object to be printed. The squeegee carriers 20, 20 comprise: a pair of holders 22A, 22B for supporting the pair of squeegees 30A, 30B disposed at an interval in a reciprocating direction; a pair of lifting members 23A, 23B for supporting and moving each holder 22A, 22B in a vertical direction; a drive device 24 including a motor 241 rotatable in a forward/reverse direction; and a reciprocation displacement mechanism 25 for converting forward/reverse rotation displacement of the motor into reciprocation linear displacement, transmitting it to each lifting member, and interlocking the lifting members so that their vertical movements become opposite.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an automatic screen printing apparatus, and more particularly to an automatic screen printing apparatus that performs switching of a squeegee used for printing and adjustment of a pressing force of a squeegee that acts on an object to be printed with a simple structure.

In general, an automatic screen printing apparatus performs printing by extruding a dye through a screen on a printed material conveyed by an endless belt. More specifically, a pair of squeegees that reciprocate in a direction perpendicular to the conveyance direction of the printed material is provided, and the dye is put between the pair of squeegees. When the squeegee is moved forward, the squeegee on the front side in the running direction is raised and positioned at a position away from the screen, and the squeegee on the rear side in the running direction is lowered and the tip portion is curved with respect to the screen. Press down. By adjusting the pressing force (hereinafter also referred to as “squeegee pressure”) by pushing down the squeegee on the rear side, the dye is effectively pushed out through the screen and permeated into the printed material.
In this state, when the squeegee travels to the end of the printed material, the squeegee is subsequently moved back. At this time, when the squeegee moves forward, the squeegee, which has been localized at a position away from the screen, is lowered, the squeegee pushed down with respect to the screen is raised, and the squeegee used for printing is switched (for example, see Patent Document 1). ).

  In the automatic screen printing apparatus of Patent Document 1, switching of the squeegee used for printing and adjustment of the squeegee pressure by pressing down the squeegee to be applied to the object to be printed are performed by different mechanisms. The squeegee used for printing is switched by a pair of slide racks to which the squeegees are respectively attached and a pinion shaft positioned between the pair of slide racks. As the squeegee moves forward, the switching shaft is pulled through the roller chain to rotate the pinion shaft, and the rotation of the pinion shaft raises the slide rack on the front side in the running direction and lowers the slide rack on the rear side. When the squeegee is moved backward, the switching shaft is pulled in the opposite direction to that of the forward movement, the slide rack that has been raised is lowered, and the slide rack that has been lowered is raised, thereby switching the squeegee. Is done.

  Further, the squeegee pressure adjustment by pushing down the squeegee is performed as follows. The squeegee is supported by a squeegee support, and the squeegee support is attached to the slide rack so that the height can be adjusted up and down by an adjustment screw. By rotating the adjusting screw with a squeegee pressure adjusting motor, the squeegee is pushed down to adjust the squeegee pressure.

Japanese Patent Publication No.8-18424

  However, in the automatic screen printing apparatus disclosed in Patent Document 1, switching of the squeegee used for printing and adjustment of the squeegee pressure applied to the object to be printed are performed by different mechanisms, so the structure of the apparatus is complicated and the number of parts is reduced. There was a problem of increasing. In addition, since the number of parts is large, there is a problem that parts tolerances are accumulated and an error becomes large when adjusting the pressurizing amount.

  The present invention has been made in view of the above problems, and provides an automatic screen printing apparatus that performs a squeegee pressure adjustment by switching a squeegee used for printing and adjusting a squeegee pressure by depressing the squeegee with a simple structure. The challenge is to do.

  The automatic screen printing apparatus according to the present invention includes a screen along the surface of the object to be printed, a squeegee carrier that reciprocates along the screen, and a pressing force that is supported by the squeegee carrier and acts on the screen during forward and backward movements. A forward movement and a pair of forward movement squeegees for printing on a printed material, wherein the squeegee carrier supports the pair of squeegees arranged at intervals in the reciprocating direction. A pair of elevating members, a pair of elevating members that individually move up and down with respect to the screen while supporting each holder, a drive device including a motor capable of forward and reverse rotation, and forward and reverse rotational displacement of the motor. A reciprocating displacement mechanism that converts each reciprocating linear displacement to be transmitted to each elevating member and interlocks each elevating member so that the elevating operation is reversed. The purpose of is achieved by the automatic screen printing device.

  According to the above configuration, when the squeegee carrier moves forward, the reciprocating displacement mechanism converts the forward / reverse rotational displacement of the motor into a reciprocating linear displacement and transmits it to each elevating member, and is supported by the elevating member. The moving squeegee is lowered and the returning squeegee is raised. When the squeegee carrier moves backward, similarly, the forward squeegee is raised and the backward squeegee is lowered to switch the squeegee used when the squeegee carrier reciprocates. Further, by adjusting the rotational displacement amount of the motor, the linear displacement amount of the elevating member is adjusted, the height of the squeegee below is changed, and the pressing force due to the pressing down of the squeegee is adjusted.

  In this way, the reciprocating displacement mechanism is operated by a single motor to switch the squeegee used for printing and to adjust the pressing force by pushing down the squeegee. Therefore, switching the squeegee used for printing as in the prior art. Compared to the case where the adjustment of the pressing force by pushing down the squeegee is performed by separate mechanisms, the configuration is simple and the number of parts is reduced. Further, the accumulation of component tolerance due to the large number of components is eliminated, and the pressing force can be adjusted with high accuracy.

  In a preferred embodiment, a control mechanism is further provided for controlling the rotational displacement of the motor in accordance with the pressing force applied to the printed material.

  According to said structure, a raising / lowering member raises / lowers by rotating a motor, the squeegee supported by the raising / lowering member is pushed down toward to-be-printed material, and a front-end | tip part curves. The reaction force generated by this bending acts as a pressing force against the printed material. By controlling the amount of rotational displacement of the motor, the amount of linear displacement of the elevating member is controlled, so that it is possible to control the squeegee pressure that acts on the fabric to be printed.

  In a preferred embodiment, the reciprocating displacement mechanism includes a pair of racks provided in parallel so that the tooth surfaces face each lifting member, and teeth on the outer periphery located between the racks mesh with the teeth of each rack. Including a pinion gear.

  According to said structure, since a pair of rack and the pinion gear located between racks are provided, each raising / lowering member can be interlock | cooperated so that raising / lowering operation may be reverse.

  It is preferable that the reciprocating displacement mechanism further includes a gear mechanism that transmits a forward / reverse rotational displacement of the motor to the pinion gear.

  As a preferred embodiment, the drive device includes a detection mechanism for detecting a rotational displacement amount of the motor, and the control mechanism is a linear displacement amount of the elevating member from an origin at which a desired pressing force is obtained for each squeegee. And a control device for controlling the operation of the motor so that the rotational displacement detected by the detection mechanism matches the set value. Yes.

  When the linear displacement amount of the elevating member corresponding to the desired pressing force is instructed, the control device stores the rotational displacement amount of the motor corresponding to the linear displacement amount of the elevating member in the memory as a set value, and the detection mechanism The detected rotational displacement amount of the motor is matched with the set value. This makes it possible to apply a desired pressing force to the printed material.

  The motor is preferably a servo motor.

  The memory may store, as a set value, a rotational displacement amount of the motor corresponding to a linear displacement amount of the elevating member from the origin when the position of the elevating member when the tip of the squeegee is in contact with the printed portion. Good.

The printed portion may be an endless belt on which the printed fabric is placed, may be a printed fabric, or may be a screen placed on the surface of the printed fabric.
The origin is detected before printing starts. When the origin is detected in a state where the fabric to be printed is not placed on the endless belt, the position of the elevating member when the tip of the squeegee contacts the endless belt can be used as the origin.

  The memory preferably stores the set value for each position in correspondence with the reciprocating position of the squeegee carrier relative to the object to be printed.

  According to the above configuration, the control mechanism can set the reciprocating position of the squeegee carrier during the reciprocating movement of the squeegee carrier by setting the set value of the rotational displacement amount of the motor to a different value for each reciprocating position of the squeegee carrier. It is possible to change the squeegee pressure according to the above.

  When printing at the reciprocating position of the squeegee carrier, due to air mixing into the dye, air mixing into the lower surface of the screen, excessive permeation or poor transmission of the dye, a portion of the squeegee carrier that is highly dyed parallel to the squeegee at the reciprocating position. Dyeing spots may occur depending on the reciprocating position of the squeegee carrier, such as a thin part of the dyeing parallel to the squeegee at another position. By setting the motor rotation fluctuation amount at this position to an optimal value and adjusting the squeegee pressure by changing the motor rotation fluctuation amount, that is, the height of the squeegee during reciprocation of the squeegee carrier, Spots can be reduced.

  According to the present invention, the reciprocating displacement mechanism is operated by one motor to switch the squeegee used for printing and to adjust the pressing force by pushing down the squeegee, so that the squeegee used for printing as in the prior art. Compared to the case where the switching and the adjustment of the pressing force by pushing down the squeegee are performed by separate mechanisms, the configuration is simple and the number of parts is reduced. In addition, accumulation of component tolerances due to the large number of components is eliminated, and squeegee pressure adjustment can be performed with high accuracy.

It is a top view of the automatic screen textile printing apparatus concerning one embodiment of this embodiment. It is the side view seen from the AA line of FIG. FIG. 3 is a plan view of FIG. 2. It is the side view seen from the BB line of FIG. It is explanatory drawing which shows the setting value of the speed of the reciprocation of a squeegee carrier. It is a block diagram which shows the structure of a control mechanism. It is explanatory drawing which shows the example of the setting of the total linear displacement amount of the raising / lowering member from a squeegee origin. It is explanatory drawing which shows the example of the correspondence table of the linear displacement amount of a raising / lowering member, and the rotational displacement amount of a servomotor. It is explanatory drawing which shows the example of the conversion table of the reciprocating position of a squeegee carrier, and the setting value of the rotational displacement amount of a servomotor. It is a block diagram for demonstrating the function of a control apparatus. It is a flowchart which shows operation | movement until the printing operation start of an automatic screen printing apparatus. It is the side view seen from the AA line of FIG. 1 which shows the state by which the ON signal from the carrier origin detection sensor was detected. It is the side view seen from the AA line of FIG. 1 which shows the state which raised the raising / lowering member only by the carrier origin displacement amount. It is the side view seen from the AA line of FIG. 1 which shows the state by which the squeegee was attached to the raising / lowering member of FIG. It is the side view seen from the AA line of FIG. 1 which shows the state which the front-end | tip of the squeegee rubber contact | abutted to the endless belt surface. It is a flowchart which shows control of the servomotor after a printing operation start.

Embodiments of the present invention will be described with reference to the drawings.
(Automatic screen printing equipment as a whole)
As shown in FIG. 1, an automatic screen printing apparatus 1 includes an endless belt 3 for conveying a printing object C or the like onto a machine base 2, a screen 4 along the surface of the printing object C, a printing unit 5, and the like. And an operation box 6 in which a control mechanism 70 for controlling the printing unit 5 according to the squeegee pressure to be applied to the printed material C is provided. Note that a plurality of screens 4 and printing units 5 are provided along the endless belt 3, but only one is described in the present embodiment.

  The endless belt 3 is configured to intermittently convey the printed material C in the direction of arrow X from right to left in FIG. The endless belt 3 is driven by drive rollers (not shown) provided at both ends of the automatic screen printing apparatus 1. Since the endless belt 3 has a sticky surface on which the printed material C is placed, the printed material C does not slide on the belt.

  The printing unit 5 includes two guide frames 7 and 7 extending in the width direction of the printed material C (in the direction of arrow Y in FIG. 1), and the guide frames 7 and 7 guided by the guide frames 7 and 7 along the screen 4 in the direction of the arrow Y. A pair of squeegee carriers 20, 20 that reciprocate in the direction, and a pair of squeegee carriers 20, 20 that extend between the two squeegee carriers 20, 20 are supported by the squeegee carriers 20, 20. A pair of forward and backward squeegees 30A, 30B for printing on the article C to be printed is provided.

  The squeegee carriers 20 and 20 are located on both sides of the screen 4 so as to sandwich the screen 4. The squeegee carriers 20 and 20 are slidably supported by the guide frames 7 and 7.

  The reciprocation of the squeegee carriers 20 and 20 is performed by the printing unit driving unit 10. More specifically, the textile printing unit drive unit 10 is equipped with a drive motor (not shown), and is connected to the drive motor to be rotationally driven, and timing pulleys provided at both ends of the connection shaft 11. 9 and the timing belt 8 driven by the timing pulley 9, the squeegee carriers 20 and 20 are reciprocated.

  The textile printing unit driving unit 10 is further equipped with a pulse transmitter (for example, a rotary encoder) to detect the reciprocating position (mm) of the squeegee carriers 20 and 20. Although details will be described later, the pulse transmitter sends a signal indicating the reciprocating position of the squeegee carriers 20, 20 to the printing unit drive unit control means 725 of the control device 72 of the control mechanism 70. The printing unit driving unit control means 725 controls the operation speed of the key carrier 20, 20 relative to the reciprocating position.

The squeegee carriers 20 and 20 have speeds set relative to their reciprocating positions, for example, as shown in FIG. In FIG. 5, the solid line indicates the set value of the speed at the time of forward movement, and the broken line indicates the set value of the speed at the time of backward movement.
The squeegee carriers 20 and 20 are accelerated from the squeegee pressurization start position so as to reach a predetermined low speed (for example, a speed of 0.3 m / s), and are positioned at a predetermined distance (for example, 10 mm) from the squeegee pressurization start position. The speed is once set to zero. This position is referred to as a printing start position. Thereafter, the vehicle is accelerated to a predetermined speed (for example, a speed of 3.0 m / s) higher than the speed to the squeegee pressurization start position, and after maintaining the predetermined speed, the speed becomes zero at the printing end position. . The actual textile printing area is the area shown in FIG.
In the normal printing operation, the same operation as when the squeegee carriers 20 and 20 are moved backward is performed.
In a special printing operation, acceleration at a low speed is not performed at the time of reverse movement, but is accelerated to a predetermined high speed (for example, speed of 3.0 m / s) from the start of reverse movement, and the printing end position ( The speed may be 0 at the printing start position during forward movement).

  This textile printing unit 5 reciprocates the squeegees 30A and 30B along the width direction of the article to be printed C (the direction of the arrow Y) while the dye is put between the pair of squeegees 30A and 30B. C is printed. In FIG. 2, assuming that the left side is the direction in which the squeegee carriers 20 and 20 move forward, and the right side is the direction in which the squeegee carriers 20 and 20 move backward, when moving the squeegee carriers 20 and 20 forward, The squeegee 30B is lifted to move away from the printing portion such as the endless belt 3, the printed material C, and the screen 4, and the forward squeegee 30A located on the right side is lowered and brought into contact with the printing portion to bring the tip portion into contact. The printed part is pressed by bending. When the squeegees 30A and 30B travel to the end of the printing object C, the squeegee carriers 20 and 20 are moved backward. At this time, the forward squeegee 30A is lifted away from the printing part, and the returning squeegee 30B is moved. Lower and press the printed part. In this way, during printing of the object to be printed C, the squeegees 30A and 30B alternately repeat rising and lowering.

(Squeegee carrier)
As shown in FIGS. 1 to 4, each squeegee carrier 20, 20 is slid while being guided by guide frames 7, 7, and reciprocates in a carrier case 21 having a slide shoe (not shown). A pair of squeegee support holders 22A and 22B for supporting a pair of squeegees 30A and 30B arranged at intervals (in the direction of arrow Y in FIG. 1), and a screen that supports each squeegee support holder 22A and 22B. 4, a pair of elevating members 23 A and 23 B that individually move up and down, a drive device 24 including a servo motor 241 capable of forward and reverse rotation, and a forward and reverse rotational displacement of the servo motor 241 are converted into a reciprocating linear displacement. In addition, a reciprocating displacement mechanism 25 that incorporates the elevating members 23A and 23B so as to transmit the elevating members 23A and 23B to each other and reverse the elevating operation is incorporated. It has been.

  The carrier case 21 accommodates a drive device 24 that includes a servo motor 241 and a pulse transmitter 242 that is a detection mechanism for detecting the amount of rotational displacement of the servo motor 241. Is connected to the reciprocating displacement mechanism 25. The pulse transmitter 242 is, for example, a rotary encoder.

The reciprocating displacement mechanism 25 includes a pair of racks 251A and 251B, a pinion gear 252 and a gear mechanism 253.
As shown in FIGS. 2 and 3, the gear mechanism 253 includes a drive-side bevel gear 253 a connected to the rotation shaft of the servomotor 241 and a driven-side bevel gear 253 b connected to the gear shaft 252 a of the pinion gear 252. The forward / reverse rotational displacement of the servo motor 241 is transmitted to the gear shaft 252a of the pinion gear 252 disposed so as to be orthogonal to the rotation axis of the servo motor 241. That is, the rotation shaft of the servo motor 241 is arranged in a direction in which the carrier case 21 reciprocates, and the gear shaft 252a of the pinion gear 252 is arranged in a direction orthogonal to the direction in which the carrier case 21 reciprocates. The forward / reverse rotational displacement of the servo motor 241 is transmitted to the gear shaft 252a of the pinion gear 252.

  The gear shaft 252 a of the pinion gear 252 is a side wall that forms the carrier case 21, and passes through the side wall that faces the carrier case 21 of the other squeegee carrier 20, 20 across the screen 4. A pair of elevating members 23A and 23B are provided on the outer surface of the side wall of the carrier case 21 with a space in the direction in which the carrier case 21 reciprocates, and a pair of racks 251A and 251B are provided on each elevating member 23A and 23B. Each is provided. The pair of racks 251A and 251B are provided in parallel so that the tooth surfaces face each other, and a pinion gear 252 is provided between the racks 251A and 251B so that the outer peripheral teeth mesh with the teeth of the racks 251A and 251B. ing.

In order to detect the amount of rotational displacement (hereinafter referred to as the carrier origin) of the servo motor 241 where the elevating members 23A and 23B have the same height, the surface of the elevating members 23A and 23B facing the side surface of the carrier case 21. The carrier origin detection dog 26a is provided on the outer surface of the side wall of the carrier case 21, and a carrier origin detection sensor 26b is provided on the outer surface of the carrier case 21 so as to face the carrier origin detection dog 26a by raising and lowering the raising and lowering members 23A and 23B. When the carrier origin detection dog 26a passes the side of the carrier origin detection sensor 26b by the elevation of the elevation members 23A and 23B, an ON signal is transmitted to the operation box 6. After detecting the ON signal, the carrier origin detection sensor 26b and the carrier origin detection dog 26a are attached so that the pair of elevation members 23A and 23B are at the same height when the elevation members 23A and 23B are raised by a predetermined distance. Yes.
The carrier origin detection dog 26a and the paired carrier origin detection sensor 26b are provided only on one lifting member 23A side.

Squeegee support holders 22A and 22B for supporting the squeegees 30A and 30B are attached to the pair of elevating members 23A and 23B, respectively.
As shown in FIGS. 2 and 4, the squeegees 30A and 30B include squeegee brackets 31A and 31B, squeegee holders 32A and 32B, squeegee rubbers 33A and 33B held by the squeegee holders 32A and 32B, and squeegee rubbers 33A and 33B. Are provided on the squeegee holders 32A and 32B. The squeegee brackets 31A and 31B are attached to the squeegee holders 32A and 32B by bolting or the like, and the squeegee brackets 31A and 31B are supported by the squeegee support holders 22A and 22B.

(Squeegee height adjustment)
Generally, rubber (natural rubber or synthetic rubber) is used as the squeegee rubbers 33A and 33B of the squeegees 30A and 30B for performing printing. As shown in FIG. 2, the squeegee rubbers 33 </ b> A and 33 </ b> B are bent at the tip by being pushed down by a set value S from the squeegee origin (described later). The reaction force R generated by this bending acts as a squeegee pressure, and the color density of the printing and the penetration degree differ depending on the magnitude of the reaction force R. Originally, it is preferable to detect and control the reaction force R directly as a squeegee pressure. However, since it is difficult to detect the squeegee pressure, the push-down displacement amount S of the squeegees 30A and 30B is substituted for the reaction force R, and the squeegee 30A, The squeegee pressure is adjusted by adjusting the height of 30B.

(Control mechanism 70)
In FIG. 1, an operation box 6 is arranged on the operation side of the textile printing unit 5. The operation box 6 is connected to the textile printing unit driving unit 10, the servo motor 241, the pulse transmitter 242, and the carrier origin detection sensor 26b by a signal line (not shown).

The operation box 6 is provided with a control mechanism 70. As shown in FIG. 6, the control mechanism 70 includes an input / output terminal 71, a control device 72, a memory 73, and an operation panel 74.
The input / output terminal 71 is connected to the textile printing unit driving unit 10, the servo motor 241, the pulse transmitter 242, and the carrier origin detection sensor 26b via a signal line, and receives a signal from the signal line and controls the signal line. The signal from 72 is sent. Instead of the input / output terminal 71, a communication interface may be used to wirelessly connect the printing unit driving unit 10, the servo motor 241, the pulse transmitter 242, the carrier origin detection sensor 26b, and the control mechanism 70.

  The control device 72 is composed of, for example, a CPU and a memory serving as a work area. The control device 72 executes the program stored in the memory 73, thereby controlling the memory 73 and the operation panel 74 and realizing the functions (described later) shown in FIG.

The operation panel 74 is a touch panel, for example, and includes an input key for inputting a linear displacement amount of the elevating members 23A and 23B on the screen. Since the squeegees 30A and 30B move up and down integrally with the elevating members 23A and 23B, the linear displacement amount of the elevating members 23A and 23B corresponds to the above-described push-down displacement amount S of the squeegees 30A and 30B.
Specifically, the first linear displacement amount and the second linear displacement amount of the elevating members 23A and 23B are input from the operation panel 74, and the sum of the first linear displacement amount and the second linear displacement amount is the squeegee. This is the total linear displacement amount of the elevating members 23A and 23B from the origin. The first linear displacement amount is a displacement amount for realizing the squeegee pressure necessary for pushing the dye into the screen 4, and the second linear displacement amount is printed by trial printing or the like at the first linear displacement amount. This is the amount of displacement set to further increase or decrease the squeegee pressure from the amount corresponding to the first linear displacement amount when dyed spots or the like are found on the object C. The second linear displacement amount may be constant during the reciprocation of the squeegee carriers 20 and 20, or may be set so that the linear displacement amount is changed during the reciprocation of the squeegee carriers 20 and 20.

7A to 7F are examples of set values of the total linear displacement amounts of the elevating members 23A and 23B from the squeegee origin input from the operation panel 74. FIG. 7A to 7F, the first linear displacement amount is set as a set value from the squeegee press start position of the squeegee carriers 20 and 20 to the printing start position. In this way, by setting the first linear displacement amount from the squeegee pressurization start position to the printing start position as a set value, the squeegees 30A and 30B are bent while the squeegee carriers 20 and 20 are moved, and the pressurization operation is performed. Since this is done, the buckling load of the squeegees 30A and 30B is reduced.
FIG. 7A shows an example in which the second linear displacement amount is set to zero and the set value is set to the first linear displacement amount from the squeegee pressurization start position to the printing end position.
FIG. 7B shows an example in which the second linear displacement amount is set to a predetermined constant value at the printing start position.
In FIG. 7C, the second linear displacement amount is set to a predetermined value at the printing start position, and the second linear displacement amount is zero at the printing end position (that is, the set value is the same as the first linear displacement amount). It is an example set so as to decrease linearly so as to satisfy (linear pressure control). The predetermined value may be a negative value, and may be increased linearly so as to be zero at the printing end position.
In FIG. 7D, the second linear displacement amount is set to zero at the printing start position and the printing end position, and is changed in a curved shape so as to be a predetermined value at an intermediate position between the printing start position and the printing end position. This is an example of setting. The predetermined value may be a negative value, and the position where the predetermined value is set may be an arbitrary position between the printing start position and the printing end position instead of the intermediate position.
FIG. 7E shows an example in which the second linear displacement amount is set to zero at the printing start position and set to a predetermined value in a stepped manner at the predetermined position. In this case, the distance from the printing start position to the predetermined position is also input from the operation panel 74.
FIG. 7F shows an example in which the second linear displacement amount is set to a predetermined value at the printing start position and set to zero at the middle position. In this case, the distance from the printing start position to the predetermined position is also input from the operation panel 74.

  Further, the first linear displacement amount and the second linear displacement amount of the lifting members 23A and 23B are set to the same value for the four lifting members 23A and 23B provided in the pair of squeegee carriers 20 and 20. However, a different value may be set for each of the four elevating members 23A and 23B.

The memory 73 is constituted by a storage device such as a hard disk device or a flash memory, for example, and the positions of the elevating members 23A and 23B when the tips of the squeegees 30A and 30B are in contact with the printed portion (for example, the endless belt 3) are the origins. (Hereinafter referred to as “the squeegee origin”), the rotational displacement amount of the servo motor 241 corresponding to the linear displacement amount of the elevating members 23A and 23B from the squeegee origin for obtaining the desired squeegee pressure for each of the squeegees 30A and 30B. It is stored as a set value. Specifically, the memory 73 stores a conversion table for associating the linear displacement amounts of the elevating members 23A and 23B and the rotational displacement amounts of the servo motor 241 as shown in FIG. When the set value of the linear displacement amount of the elevating members 23A, 23B corresponding to the reciprocating position of the squeegee carriers 20, 20 as shown in FIG. 7 is input from 74, the control device 72 refers to the conversion table of FIG. Then, the linear displacement amount of the elevating members 23A and 23B is converted into the rotational displacement amount of the servo motor 241, and the servo is made to correspond to the reciprocating position of the squeegee carriers 20 and 20 in the memory 73, for example, as shown in FIG. The rotational displacement amount of the motor 241 is stored as a set value for each position.
The memory 73 also stores a carrier origin displacement amount that is a rotational displacement amount of the servo motor 241 for setting the pair of elevating members 23A and 23B as the carrier origin.

  The control device 72 executes a program stored in the memory 73, thereby performing carrier origin acquisition means 721, squeegee origin acquisition means 722, input value storage means 723, servo motor control means 724, textile printing as shown in FIG. The function as the unit driving unit control means 725 is realized.

The carrier origin acquisition means 721 acquires the carrier origin that is the rotational displacement amount of the servo motor 241 when the pair of elevating members 23A and 23B have the same height, and stores them in the memory 73. Specifically, the carrier origin acquisition means 721 detects the ON signal from the carrier origin detection sensor 26b, reads the carrier origin displacement amount stored in the memory 73, and only the carrier origin displacement amount from the time when the ON signal is received. By rotating the servo motor 241 in the reverse direction, the elevating members 23A and 23B are raised by a predetermined distance corresponding to the carrier origin displacement amount from the height position of the elevating members 23A and 23B when the ON signal is received. Further, the rotational displacement amount of the servo motor 241 when the elevating members 23A and 23B are raised by a predetermined distance is stored in the memory 73 as the carrier origin.
The carrier origin may be acquired once after the automatic screen printing apparatus 1 is turned on, and the acquired carrier origin can be used until the automatic screen printing apparatus 1 is turned off. When the pulse transmitter 242 (24) is an absolute value method, the carrier origin acquired at the time of machine setting when the automatic screen printing apparatus 1 is operated for the first time can be used for the subsequent operation. It is not necessary to acquire the carrier origin again every time the device 1 is powered off.

The squeegee origin acquisition means 722 lowers the squeegees 30A and 30B in the forward and backward squeegees 30A and 30B, respectively, so that the tips of the squeegees 30A and 30B come into contact with the portion to be printed (for example, the endless belt 3). The positions of the elevating members 23A and 23B are acquired as the squeegee origin and stored in the memory 73. The squeegee origin is used as the origin of the linear displacement amount of the elevating members 23A and 23B from which a desired squeegee pressure is obtained.
Specifically, in the squeegee origin acquisition means 722, the tips of the squeegees 30A and 30B that descend integrally with the elevating members 23A and 23B come into contact with the surface of the endless belt 3, and the rotation speed of the servo motor 241 becomes “0”. The rotation displacement amount of the servo motor 241 corresponding to the linear displacement amount of the elevating members 23A and 23B at this time is stored in the memory 73 as the squeegee origin.
The squeegee origin may be acquired once after the carrier origin is acquired by the carrier origin acquisition means 721. The acquired squeegee origin is switched off from the automatic screen printing apparatus 1 or separately from the squeegees 30A and 30B. Until the squeegee is replaced, it is not necessary to acquire the squeegee origin again when the same squeegee is attached or detached for color change or the like.

  The input value storage means 723, for example, the rotational displacement amount of the servo motor 241 corresponding to the input value of the linear displacement amount of the elevating members 23A and 23B from the squeegee origin input from the operation panel 74 as shown in FIG. As shown in FIG. 9, the setting value is stored in the memory 73 in correspondence with the reciprocating position of the squeegee carriers 20 and 20 with respect to the printing object C.

  The printing unit drive unit control means 725 controls the printing unit drive unit 10 to reciprocate the squeegee carriers 20 and 20 with a set value as shown in FIG. Further, the printing unit driving unit control means 725 receives a signal indicating the reciprocating position (mm) of the squeegee carriers 20 and 20 detected by the pulse transmitter of the printing unit driving unit 10.

  When the servo motor control means 724 receives an instruction to start printing, the servo motor control means 724 obtains the reciprocating position (mm) of the squeegee carriers 20 and 20 from the printing unit drive section control means 725, and the servo motor 241 with respect to the reciprocating position of the squeegee carrier. Is read from the memory 73 for each control cycle.

  Then, the rotational displacement amount of the servo motor 241 is detected based on the number of pulses received from the pulse transmitter 242, and the operation of the servo motor 241 is controlled so that the rotational displacement amount matches the set value.

(Printing operation)
Next, the printing operation of the automatic screen printing apparatus 1 of the present invention will be described. FIG. 11 is a flowchart showing a process until the printing operation of the automatic screen printing apparatus 1 is started.
First, when the automatic screen printing apparatus 1 is turned on, the control mechanism 70 detects the carrier origin by the carrier origin acquisition means 721 of the control device 72. The control mechanism 70 stores, as carrier origin position data, the rotational displacement amount of the servo motor 241 when the elevating members 23A and 23B are raised by a predetermined distance so that the pair of elevating members 23A and 23B have the same height ( Step S1).

Specifically, the carrier origin acquisition means 721 of the control device 72 reads the carrier origin displacement amount (in the present embodiment, which is set to 26 mm, but is not limited to this) from the memory 73 and corrects the servo motor 241. The elevating member 23A is lowered by rolling. When the ON signal from the carrier origin detection sensor 26b is detected (FIG. 12), the motor control means reversely rotates the servo motor 241 by the rotational displacement amount corresponding to the carrier origin displacement amount from the time when the ON signal is received, In the illustrated example, the elevating member 23A is raised by the carrier origin displacement amount. The rotation displacement amount of the servo motor 241 when the elevating member 23A is raised by the carrier origin displacement amount is stored in the memory 73 by the carrier origin acquisition means 721.
At this time, the pair of elevating members 23A and 23B have the same height (FIG. 13).
When the carrier origin detection sensor 26b is provided on the lifting member 23B side, the servo motor 241 is driven in reverse to lower the lifting member 23B, and an ON signal from the carrier origin detection sensor 26b is detected. The elevating member 23B may be raised by the carrier origin displacement amount.

In the state where one lifting member 23A is lowered as shown in FIG. 12, the distance between one lifting member 23A and the endless belt 3 is small, and the squeegee 30A is attached to the squeegee support holder 22A provided on the lifting member 23A. Although it is difficult to attach, as shown in FIG. 13, by setting the pair of elevating members 23A and 23B to the same height, the distance from the endless belt 3 is widened, and the squeegees 30A and 30B can be easily attached to the squeegee support holders 22A and 22B.
Further, when the squeegees 30A and 30B are attached in a state where the heights of the pair of elevating members 23A and 23B are different, the distance for moving the elevating members 23A and 23B to lower the upper squeegees 30A and 30B is long and downward. The moving distance for lowering a certain lifting member 23A, 23B is shortened, and the time required for movement differs greatly depending on whether the lifting member 23A, 23B is below or above, but the pair of lifting members 23A, 23B is the same By attaching the squeegees 30A and 30B in the height state, the distance and time for moving the elevating members 23A and 23B to switch between the squeegees 30A and 30B used for textile printing are substantially the same for each elevating member 23A and 23B.

  Next, the squeegees 30A and 30B are attached to the squeegee support holders 22A and 22B (step S2). FIG. 14 shows a state in which the squeegees 30A and 30B are attached to the elevating members 23A and 23B at the same height.

  Further, the control mechanism 70 uses the squeegee origin acquisition means 722 to move the elevating members 23A when the tips of the squeegee rubbers 33A and 33B of the squeegees 30A and 30B come into contact with the printing portion for the forward and backward squeegees 30A and 30B. , 23B are acquired as the squeegee origin and stored in the memory 73 (step S3).

Specifically, the tip of the squeegee rubber 33 </ b> A of the descending squeegee 30 </ b> A contacts the surface of the endless belt 3 when the lifting member 23 </ b> A is lowered and the moment when the rotation speed of the servo motor 241 becomes “0” is detected. As an example (FIG. 15), the rotational displacement amount of the servo motor 241 corresponding to the linear displacement amount of the elevating members 23A and 23B at this time is stored in the memory 73 as the squeegee origin.
Note that the tip of the squeegee rubber 33A of the descending squeegee 30A may be in contact with the surface of the endless belt 3 when the current value of the servomotor 241 is measured and a sudden change in the current value is detected.

  Next, the amount of linear displacement of the elevating members 23A and 23B from the squeegee origin is input from the operation panel 74 (step S4). For example, as shown in FIG. 7A, the first linear displacement amount of the elevating members 23A and 23B is 3 mm, and the second linear displacement amount of the elevating members 23A and 23B is a constant value of zero. Considering the operation panel 74, the first linear displacement amount is 3 mm, the second linear displacement amount is zero, and the lifting member 23A, which is the sum of the first linear displacement amount and the second linear displacement amount, The total linear displacement amount 23B is converted into the rotational displacement amount of the servo motor 241, and stored in the memory 73 by the input value storage means 723 as a set value for each reciprocating position of the squeegee carriers 20, 20.

  Note that step S4 may be performed prior to step S3 or may be performed simultaneously with step S3.

  Next, when the start button on the operation panel 74 is pressed, the printing operation is started (step S5).

Hereinafter, control of the printing unit driving unit 10 of the control mechanism 70 after the printing operation is started will be described.
The printing unit drive unit control means 725 of the control mechanism 70 is a squeegee carrier 20 that is running from the printing start position to the printing end position as shown in FIG. , 20 and the setting values of the operation speed are read out, and the printing unit driving unit 10 is controlled to move the squeegee carriers 20 and 20 forward. After the squeegee carriers 20 and 20 reach the printing end position, the printing unit drive unit control means 725 of the control mechanism 70 moves the squeegee carriers 20 and 20 back to the printing end position (printing start position during forward movement).

  Next, the control of the servo motor 241 after the start of the printing operation will be described with reference to FIG.

  With the start of the printing operation, the servo motor control means 724 of the control mechanism 70 acquires the reciprocating position of the squeegee carriers 20 and 20 detected by the pulse transmitter of the printing unit drive unit 10 (step S11). Next, the servo motor control means 724 reads the set value of the rotational displacement amount of the servo motor 241 corresponding to the reciprocating position of the squeegee carriers 20 and 20 from the memory 73 (step S12). Then, the rotational displacement amount of the servomotor 241 is detected based on the number of pulses received from the pulse transmitter 242 (step S13), and the servomotor 241 is adjusted so that the rotational displacement amount of the servomotor 241 matches the set value. The operation is controlled (step S14). Next, the servo motor control means 724 determines whether or not the squeegee carriers 20 and 20 have reached the printing end position (S15). If the squeegee carriers 20 and 20 have reached the printing end position, the operation is terminated. -S14 is repeated.

  Until the squeegee carriers 20 and 20 move forward and the reciprocating position reaches the printing start position, as shown in FIG. 7A, the set value of the rotational displacement amount of the servo motor 241 is the first of the lifting members 23A and 23B. 1 is a value corresponding to a linear displacement amount of 1, and the servo motor 241 is controlled so that the rotational displacement amount of the servo motor 241 coincides with the set value until the squeegee carriers 20 and 20 reach the printing start position. To be done. Until the squeegee carriers 20 and 20 reach the printing start position, the operation speed of the squeegee carriers 20 and 20 is low. During this time, the elevating members 23A and 23B are lowered to the first linear displacement amount, so that the screen 4 The impact when the tip of the squeegee 30A comes into contact is reduced.

  After the squeegee carriers 20 and 20 reach the printing end position, the servo motor control means 724 of the control mechanism 70 returns the elevating members 23A and 23B to the squeegee origin (step S16), and the operation ends.

  When the squeegee carriers 20 and 20 start returning, the servo motor control means 724 of the control mechanism 70 performs the operation shown in FIG. 16 from the start to the end of printing.

  According to the present invention, the reciprocating displacement mechanism 25 is operated by one servo motor 241 to switch the squeegees 30A and 30B used for printing and adjust the squeegee pressure by pressing the squeegees 30A and 30B. Compared to the case where the switching of the squeegee used for textile printing and the adjustment of the squeegee pressure by pressing down the squeegee are performed by separate mechanisms as in the prior art, the configuration is simple and the number of parts is reduced. Further, the accumulation of component tolerances due to the large number of components is eliminated, and the pressure adjustment of the squeegees 30A and 30B can be performed with high accuracy.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Automatic screen printing apparatus 3 Endless belt 4 Screen 5 Printing unit 6 Operation box 20, 20 Squeegee carrier 22A, 22B A pair of squeegee support holder 23A, 23B A pair of raising / lowering member 24 Drive apparatus 241 Servo motor 242 Pulse transmitter (position detection mechanism) )
25 Reciprocating displacement mechanisms 251A, 251B A pair of racks 252 Pinion gears 253 A gear mechanism 30A, 30B A pair of squeegees 70 A control mechanism 72 A control device 73 A memory 74 An operation panel C

Claims (8)

A screen along the surface of the object to be printed, a squeegee carrier that reciprocates along the screen, and a squeegee carrier that is supported by the squeegee carrier and applies a pressing force to the screen during forward and backward movements. In an automatic screen printing apparatus including a pair of moving and forward squeegees,
The squeegee carrier includes a pair of holders for supporting the pair of squeegees arranged at intervals in a reciprocating direction, and a pair of elevating members that support the holders and individually move up and down with respect to the screen. And a drive device including a motor capable of forward / reverse rotation, and each lifting member so that the forward / backward rotational displacement of the motor is converted into a reciprocating linear displacement and transmitted to each lifting member, and the lifting operation is reversed. An automatic screen printing apparatus comprising a reciprocating displacement mechanism for interlocking with each other. The automatic screen printing apparatus according to claim 1,
An automatic screen printing apparatus further comprising a control mechanism for controlling the rotational displacement of the motor in accordance with the pressing force applied to the object to be printed.   The reciprocating displacement mechanism includes a pair of racks provided in parallel so that tooth surfaces face each other on each lifting member, and a pinion gear located between the racks and having outer peripheral teeth meshing with the teeth of each rack. Item 3. The automatic screen printing apparatus according to Item 1 or 2.   The automatic screen printing apparatus according to claim 3, wherein the reciprocating displacement mechanism further includes a gear mechanism that transmits a forward / reverse rotational displacement of the motor to the pinion gear. The drive device includes a detection mechanism for detecting a rotational displacement amount of the motor,
The control mechanism includes a memory for storing, as a set value, a rotational displacement amount of the motor corresponding to a linear displacement amount of the elevating member from the origin at which a desired pressing force is obtained for each squeegee, and a circuit detected by the detection mechanism. The automatic screen printing apparatus according to claim 2, further comprising a control device that controls the operation of the motor so that the amount of dynamic displacement matches the set value.   The automatic screen printing apparatus according to claim 1, wherein the motor is a servo motor.   The said memory memorize | stores the rotational displacement amount of the motor corresponding to the linear displacement amount of the raising / lowering member from the origin as a setting value from the position of the raising / lowering member when the front-end | tip of a squeegee touches a to-be-printed part as an origin. 5. The automatic screen printing apparatus according to 5.   6. The automatic screen printing apparatus according to claim 5, wherein the set value for each position is stored in the memory in correspondence with a reciprocating position of the squeegee carrier with respect to the object to be printed.

Images