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Publication numberUS3774534 A
Publication typeGrant
Publication dateNov 27, 1973
Filing dateMar 9, 1972
Priority dateDec 15, 1971
Publication numberUS 3774534 A, US 3774534A, US-A-3774534, US3774534 A, US3774534A
InventorsIchinose S
Original AssigneeIchinose S
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Rotary screen printing machine
US 3774534 A
Abstract
A rotary screen printing machine having a plurality of printing sections, wherein when a rotary screen of one printing section is at a position raised from the printing operation position, and the printing operation is conducted by a plurality of printing sections alternately, whereby time required for change of color or design or for washing of screens, squeegees, etc. can be greatly minimized and the machine operation efficiency can be greatly increased.
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Description  (OCR text may contain errors)

United States Patent 11 1 Ichinose 1 ROTARY SCREEN PRINTING MACHINE [76] Inventor: Shiro Ichinose, 11-8, 4-chome,

- Shinohara Kita-machi, Nada-ku, v Kobe, Japan [22] Filed: Mar. 9, 1972 [21] App]. No.: 233,039

[30] Foreign Application Priority Data Nov. 27, 1973 3,572,240 3/1971 BOhm 101/116 3,420,167 l/l969 Van Der Winden 101/116 FOREIGN PATENTS OR APPLICATIONS 266,650 12/1966 U.S.S.R 101/116 Primary Examiner-Robert E. Pulfrey Assistant ExaminerEugene H. Eickholt AztorneyE. F. Wenderoth et al.

[5 7] ABSTRACT A rotary screen printing machine having a plurality of printing sections, wherein when a rotary screen of one printing section is at a position raised from the printing operation position, and the printing operation is conducted by a plurality of printing sections alternately, whereby time required for change of color or design or for washing of screens, Squeegees, etc. can be greatly minimized and the machine operation efficiency can be greatly increased.

8 Claims, 5 Drawing Figures [56] References Cited UNITED STATES PATENTS 3,291,044 12/1966 Van Der Winden 101/118 3,585,930 6/197l .Bohm 3,565,002 2/1971 Boehm 101/116 PATENTEUHUVZ? ms SHEET 10F 5 (5H1 km wm m2 v I ROTARY SCREEN PRINTING MACHINE This invention relates to a rotary screen printing machine having a plurality of printing sections. More particularly, the invention relates to a rotary printing machine having a plurality of printing sections, wherein when a rotary screen of one printing section is in the printing operation position, a rotary screen of another printing section is at a position raised from the printing operation position, and the printing operation is conducted by a plurality of printing sections alternately.

As compared with, for instance, a flat screen printing machine, a rotary screen printing machine can attain a high productivity because of its specific mechanism in which high speed printing can be conducted continuously, and the rotary screen printing machine is advantageous over the roller printing machine in the printing that the print cost is low. Further, in therotary screen printing machine a color change or design change may be accomplished very easily. Accordingly, it may be said thatthe rotary screen printing machine is a very advantageous printing machine.

A rotary screen printing machine of the type that has heretofore been used broadly comprises pulleys provided at both ends of the printing operation zone, at least one of which is driven, a printing belt supported and driven by said pulleys, which is adapted for supporting a material to be printed and transporting it to the printing operation zone, a squeegee member mounted in the interior of the rotary screen for squeezing a printing paste or ink into the material to be printed through said screen, and a drive mechanism for driving the rotary screen at a speed synchronized with the speed of the printing belt.

However, the known rotary screen printingmachine is still not high in productivity and machine operation efficiency, because the time required for washing the screens and the squeegee members is considerable at the time of exchange of color or design and loss of time, therefore, is very extensive.

Accordingly, itis a primary object of this invention to provide a rotary screen printing machine wherein such operations which cause a loss of time in the conventional machine are accomplished during the printing operation, whereby the time required for the change of color or design can be minimized and the machine operation efficiency can be greatly height-- ened.

Another object of this invention is to provide a rotary screen printing machine wherein a plurality of printing sections are provided in the printing operation zone so that when-a rotary screen of one printing section is in the printing operation position, a rotary screen of another printing section is in a position raised from the printing operation position, and the printing operation is conducted by a plurality of printing sections alternately.

In accordance with this invention, there is provided a rotary screen printing machine comprising pulleys provided on both ends of the printing operation zone, at least one of which is driven, a printing belt supported and driven by said pulleys, which is adapted for supporting a material to be printed and transporting it to the printing operation zone, a squeegee member mounted in the interior of the rotary screen for squeezing a printing paste or ink onto the material to be printed, and a drive mechanism for driving the rotary screen at a speed synchronized with thespeed of the printing belt, wherein said printing operation zone comprises a plurality of printing sections independent of each other, each of said printing sections comprising at least one rotary screen, a printing frame supporting said rotary screen and a lift mechanism for moving said printing frame vertically, said members being so arranged that when a rotary screen of of one printing section is in the printing operation position, a rotary screen of another printing section is raised from the printing operation position, and the preparation for printing and the printing operation are conducted by a plurality of sections alternately.

This invention will be explained more fully by reference to the accompanying drawings, which illustrate an embodiment of this invention.

FIG. 1 is a side view illustrating the drive mechanism of the rotary screen printing machine of this invention.

FIG. 2 is a side view illustrating the lift mechanism of the rotary screen printing machine illustrated in FIG. 1.

FIG. 3 is an enlarged partial side view illustrating the supporting mechanism for the bearing device of the rotary screen printing machine of this invention.

FIG. 4 is a top plan view illustrating the supporting mechanism for the bearing device shown in FIG. 3.

FIG. 5 is a circuit diagram of the circuit for operating the printing machine.

In FIGS. 1 and 2, on opposite ends of a frame 1, namely on the ends, and change zone A, B to zones A and B of the printing operation zone A, B, a drive pulley 2 and an idle pulley 3 are mounted, and a printing endless belt 4 is stretched between drive and idle pulleys 2 and 3, and supported and driven by these pulleys. For driving the drive pulley 2, a drive shaft on which the drive pulley 2 is fixed is provided with a sprocket or pulley 6 mounted thereon, and the driving force of a motor M is transmitted to the drive pulley 2 by means of a chain 9 (or drive belt 9) extending between a drive sprocket 8 (or pulley 8) of a reduction gear 7 mounted on the motor M and said sprocket 6 (or pulley 6).

Above the idle pulley 3, a material 10 to be printed, such as a cloth or fabric, is fed on the upper surface of the printing belt 4, and supported and transported to the printing operation zones A and B by the printing belt 4. The material 10' which has been printed is separated from the upper surface of the printing belt 4 above the drive pulley 2, following which the material 10' is forwarded to the drying or winding step. Above the idle pulley 3, a press roller 11 is provided so that it has a contact with the printing belt 4 travelling on the idle pulley 3, and the material 10 to be printed is fed between the press roller 1 l and the printing belt 4 over guide rollers 12 mounted upstream of the press roller 11. Above the drive pulley 2 there is provided a guide roller 13 to separate from the printing belt 4 the material 10' which has been printed and forward it to the subsequent treatment zone.

Above the printing operation zones A and B namely above the printing belt 4 stretched between the drive and idle pulleys 2 and 3, a plurality of rotary screens 14 are disposed. In the interior of each rotary screen 14 a squeegee member 15 is provided for squeezing a printing ink or paste onto the material to be printed through said screen. At the time of the printing operation, the rotary screens '14 contact the material 10 to be printed, which is supported on the printing belt 4,

and is driven at a speed synchronized with the travelling speed of the printing belt 4. Thus, an image of a pattern corresponding to that on the rotary screen is printed and formed on the material to be printed. Where there is a plurality of rotary screens, their position and phase are so arranged that a desired pattern or combination of colors can be formed on the material 10 to be printed.

The prominent characteristic feature of this invention is that the printing operation zone has a plurality of printing sections A and B independent of each other and each printing section has at least one rotary screen, a printing frame supporting said rotary screen and a lift mechanism for moving said printing frame vertically. By provision of a plurality of such printing sections, each having an independent lift mechanism, along the single printing belt 4, it is possible when the rotary screen of one printing section is in the printing operation position, namely in the position contacting the material 10 to be printed which is supported on the printing belt 4, the rotary screen of the other printing section is at a position raised from the printing operation position. As a result, the printing operation can be conducted by a plurality of printing sections A and B alternately, and while one printing section is conducting the printing operation, washing of the screen or squeegee member or changing of the color or design can be effected in the other printing section.

In the following explanation referring to the drawing, the same reference numbers are used for corresponding members and mechanisms common to both printing blocks A and B, and when an explanation is given specifically for either of the blocks A or B, the letter A" or 8" is prefixed to the reference number.

As is illustrated in FIGS. 1 and 2, two printing sections A and B are provided along the direction of travel of the printing belt 4. In this invention, in order to support rotary screens 14 of sections A and B for vertical movement, a vertically movable printing frame 22 is provided as is illustrated in FIG. 2. In this invention, it is preferred that the bearing device for each rotary screen 14 be mounted on a supporting member, one end of which is pivoted on a supporting shaft and the other end of which is attached to the vertically movable printing frame 22, and that a screen gear attached to the rotary screen 14 be engaged with a screen-driving gear through an idle gear on said supporting shaft.

For attaining the above structure, as is illustrated in FIG. 3, the bearing device 16 for each rotary screen 14 is mounted in a supporting member 21 pivoted at one end 17 on a supporting shaft 18, and the other end 19 is attached to a vertical member 20 on the printing frame 22. The shaft 18 is supported rotatably mounted on the frame 1. Thus, the supporting member 21 can oscillate around the supporting shaft 18 as the center, and with oscillation of the supporting member 21, the rotary screen 14 can also oscillate around the supporting shaft 18 as the center. Each vertical member 20 projects above the printing frame 22, and a mechanism for vertically moving the printing frame 22 is mounted on the frame 1. As can be seen from FIG. 2, one embodiment of such a mechanism comprises racks on the printing frame 22 extending in the downwardly vertical direction, and pinions are rotatably engaged with the racks 23. One end of an oscillating arm 25 is fixed to each pinion 24, and the other end of the oscillating arms 25 are oscillatably mounted on a slide shaft 26.

One end of the slide shaft 26 is attached to an arm 28, one end of which is oscillatably mounted on a shaft 27. The other end of the arm 28 is connected with a piston member 30 of a pressure fluid cylinder 29. When the slide shaft 26 is shifted in the right direction by introducing into the cylinder 29 a pressure fluid such as compressed air or oil, the pinion 24 is rotated in the counter-clockwise direction and the rack 23 is shifted upwardly, whereby the printing frame 22, and, in turn, the rotary screens 14 are raising up. The lifting and lowering of the printing frame 22 and the rotatary screens 14 may be accomplished by employing a known hydraulic machine instead of the lifting and lowering mechanism shown in FIG. 2.

In this invention, it is preferred that, as is illustrated in FIG. 3, the squeegee members 15 be supported by the printing frame 22. If such method of supporting the squeegee members 15 is adopted, the squeegee members 15 are shifted a distance corresponding to the lifting distance (h,) of the printing frame 22, while the screens are lifted only a distance expressed by the following equation:

e r X z i wherein h stands for the distance the printing frame 22 is raised, 11 indicates the distance the screen 14, d designates the distance between the supporting shaft 18 and the vertical member 20 of the printing frame 22, and d represents the distance from the supporting shaft 18 to the point where each screen 14 comes into contact with the corresponding squeegee member 15. Accordingly, with the rise of the printing frame 22, between the inner surface of each screen 14 and end point of the squeegee member 15 there is formed a space expressed by the following formula:

Therefore, with the rise of the rotary screens 14, the squeegee members 15 move away from the innter surface of the rotary screens 14, with the result that at the time of stoppage of the printing operation various operations can be accomplished smoothly and easily.

The driving of the rotary screens in the printing machine of this invention is conducted in the following manner. As is illustrated in FIG. 1, a screen gear 31 is attached to the end portion of each rotary screen 14, and the gear 31 is engaged with an idle gear 32 on the supporting shaft 18. As is illustrated in FIGS. 3 and 4, a shaft 33A is mounted on the vertical member 20, and on both ends of the shaft 33A there are mounted gears 33 so that the gears 33 are engaged with screen gears 31 mounted on both ends of the rotary screen 14. With such a construction, by means of the idle gear 32, the drive force transmitted to one end of the screen 14 is conveyed to the other side of the screen 14 through the screen gear 31 on one end, the gear 33 on one end, the shaft 33A, the gear 33 on the other end and the screen gear 31 on the other end. By adopting such a construction, an undesired phenomenon of twisting of the screen can be prevented effectively. Below the idle gear 32 on each supporting shaft 18, a screen-driving gear 34 is provided which is engaged with said idle gear 32. A helical worm gear 35 is meshed with the screendriving gear 34, and is engaged with a helical gear 37 on a screen-driving shaft 36 extending in the longitudinal direction of the frame 1. By rotation of the screendriving shaft 36, the screen-driving gear 34 for each rotary screen is driven through the engagement between the helical gear 37 and the helical worm gear 35, and the drive force of the screen-driving gear 34 is conveyed to the screen gear 31 through the idle gear 32, whereby the rotary screens can be driven and rotated smoothly irrespective of the position of the screens 14.

In this invention, it is preferred that the abovementioned drive system be alternatively connected to a first drive mechanism for driving the rotary screens 14 at a speed synchronized with'the speed of the printing belt 4 and a second drive mechanism independent of said first drive mechanism, whereby at the position raised from the printing operation position the rotary screens 14 can be driven and rotated independently of other known clutch M1 to the first drive mechanism,

and the other end of the screen-driving shaft 36 is connected via a magnetic clutch or other known clutch M2 to the second drive mechanism. Any mechanism capable of driving the rotary screens 14 at a speed synchronized with the speed of theprinting belt 4 may be utilized as the first drive mechanism. For instance, the drive mechanism M for the drive pulley 2 driving the printing belt 4 may be utilized also as the first drive mechanism. However, in this invention it is preferred that the idle pulley 3 of the printing belt 4 be used as the first drive mechanism for driving and rotating the rotary screens 14 at a speed synchronized with the speed of the printing belt 4.

In order to achieve this drive, as is illustrated in FIG. 1, a drive spur gear 39 is fixed on the shaft 38 on which the idle pulley 3 is fixed, an idle gear 40 is mounted to that it is engaged with the drive spur gear 39, and an exchangeable change gear 41 is mounted so that it is engagedwith the idle gear 40. A bevel gear (not shown) is fixed to the change gear 41. From this bevel gear the drive force is transmitted through a bevel gear 42, another bevel gear 43 connected to the bevel gear 42, and still another bevel gear 44 to a drive shaft 45, one end of which is fixed to the bevel gear 44. On the drive shaft 45 are fixed a plurality of spur gears A46 and B46, which are engaged with a spur gear A47 freely movably mounted on the screen-driving shaft A36 of the printing section A and a spur gear B47 freely movably mounted on the screen-driving shaft B36 of the printing section B, respectively. The gears 47 fitted on the screen-driving shafts 36 and the magnetic or other known clutches Ml attached to the shafts 36 are arranged so that when a clutch M1 is actuated, the corresponding shaft 36 is driven and rotated by the drive force conveyed to the corresponding gear 47 and when a clutch M1 is not actuated, the corresponding spur gear 47 and the screen-driving shaft 36 can be rotated freely from the other shaft 36 and gear 47. Thus, when the clutch M l for one printing section is actuated, with the movement of the printing belt 4 the idle pulley 3 is rotated at a surface speed synchronized with the speed of the printing belt 4, and the rotation force of the idle pulley 3 is transmitted to the drive shaft 45 through the gearing mechanism comprising members 39, 40, 41, 42, 43 and 44. Then, by the engagement between spur gears 46 and 47 for the one printing section the force is conveyed to the screen-driving shaft 36 for that section, and it is then transmitted to the rotary screens 14 of that section by means of the gearing mechanism comprising members 37, 35, 34, 32 and 31. In the manner as described above, in this invention, by actuating the clutches AMI and BMI of printing sections A and B alternately, either the rotary screens A14 or the rotary screens B14 can be driven and rotated at a speed synchronized with the speed of the printing belt 4. Further, by actuating simultaneously both clutches AMI and BMI, all the rotary screens 14 of printing sections A and B can be driven and rotated at a speed synchronized with the speed of the printing belt 4.

In this invention, when the drive system illustrated in FIG. 1 is adopted, even when slippage occurs between the drive pulley 2 and the printing belt 4, it is possible to drive and rotate the rotary screens 14 at a speed completely synchronized with the speed of the printing belt 4, because the load imposed between the idle pulley 3 and the printing belt 4 is smaller than the load imposed between the drive pulley 2 and the printing belt 4 and hence, the frequency of slippage between the idle pulley 3 and the printing-belt 4 is much lower than the frequency of slippage between the drive pulley 2 and the printing belt 4. Further, the rotation of the rotary screens 14 by the idle pulley 3 is not influenced by unevenness of the elongation of the printing belt 4. The change of the diameter of a rotary screen 14, i. e., the change of the design size, may be accomplished easily by exchanging the change gear 41. It is preferred that the idle pulley 40 be mounted oscillatably around the shaft 33 yet remain engaged with the drive spur gear 39, so that a change gear 41 suitable for attaining a speed synchronized with the speed of the printing belt can be readily attached.

In FIG. 1, to the other end of the screen-driving shaft 36 of each printing section is connected a motor 48 equipped with a reduction gear for driving and rotating the rotary screen independently of the printing belt 4, through the magnetic or other known clutch M2. When the above-explained first clutch M1 for one printing section is not actuated and the second clutch M2 for that section is actuated, the screen-driving shaft 36 for that section is driven and rotated by the motor 48 equipped with a reduction gear, and the rotary screens 14 for that section are then driven and rotated by means of the gearing mechanism comprising members 37, 35, 34, 32 and 31.

The printing operation of the printing machine of this invention is conducted in the following manners.

I. Case where the printing operation is conducted by using printing sections A and B alternately:

As is illustrated in FIGS. 1 and 2, the printing frame B22 of the printing section B is at the lowermost position, namely at the printing operation position, while the printing frame A22 of the printing section A is at a position raised from the operation position, namely at the stoppage position. In this state the printing operation is conducted. In FIG. 1 the first clutch BM1 of the printing section B is acutated, while the second clutch BM2 is not actuated. The first clutch AM1 of the printing section A is not actuated, while the second clutch AM2 is either actuated or not actuated. The drive pulley 2 is driven and rotated by the drive motor M, and with the rotation of the drive pulley 2, the endless belt 4 for printing is driven, and a material 10 to be printed passes over guide rollers 12 and is fed between the pressure roller 11 and the printing belt 4 travelling on the idle pulley 3. The material 111 is supplied to the upper surface of the printing belt 4 and continuously forwarded to the printing operation zone.

With rotation of the idle pulley 3 caused by friction with the endless belt 4, the drive shaft 45 is driven and rotated. Since the clutch BMI is actuated and the clutch AMI is not actuated, only the screen-driving shaft B36 of the printing section B is driven and rotated, with the result that the rotary screens B14 of the printing section B are driven and rotated at a speed synchronized with the speed of the printing belt 4. The rotary screens B14 of the printing section B contact the material 10 on the printing belt 4. The squeegee member B has a contact the inner surface of each rotary screen B14, and causes a printing paste or ink fed to the interior of the rotary screen B14 to ooze out through the screen in the form of a pattern on the material 10 on the printing belt 4. Thus, the printing of the material 10 is effectively performed in the printing section B. The material 10' which has been printed upon is separated from the printing belt 4 on the discharge end of the printing belt 4, and is forwarded through a guide roller 13 to the subsequent treatment zone, for instance, the drying or winding zone. After passage over the drive pulley 2, the endless belt 4 for printing is subjected to such treatments as surface washing and drying, and comes to the position of the idle pulley 3, following which the above operation procedures are repeated.

Initiation of the printing operation may be effected while maintaining rotary screens 14 at the lower position such as that of the rotary screens B14 of the printing block B illustrated in FIGS. 1 and 2. However, in order to prevent wear of the rotary screens 14 at the time of initiation of the printing operation, it is preferred to initiate the operation by maintaining rotary screens 14 at the raised position such as the position of the rotary screens A14 of the printing section A in FIGS. 1 and 2 and to lower the rotary screens coincidentally with initiation of driving of the printing belt 4.

Coincidentally with the termination of the printing operation in the printing section B, a fluid is introduced into the fluid cylinder B29, and the lift rack B23 and, in turn, the printing frame B22 are lifted. With the lifting of the frame B22, the rotary screens B14 are rotated upwardly around the supporting shafts B18 and separate from the material 10 to be printed applied, which is applied on the printing belt 4. Also with the lifting of the printing frame 22, the top end of the squeegee members B15 part from the inner surface of the screens B14. By introduction of a fluid into the fluid cylinder 29, disengaging of the first clutch BMI and actuation of the second clutch BM2 are automatically performed coincidentally. As a result, the screendriving shaft B36 is driven and rotated by the motor B48 equipped with a reduction gear, and the rotary screens B14 are driven and rotated, independently of the printing belt 4, by the gearing mechanism comprising members 37, 35, 34, 32 and 31. Thus, at the time of termination of the printing operation, rotary screens 14 are lifted from the printing operation position, and at this raised position they can be driven and rotated independently of the printing belt 4, whereby the undesired phenomenon that at the time of stoppage of the printing operation a printing paste or ink flows out through the screen onto the material to be printed or the printing belt can be effectively prevented.

Subsequently to the raising of the printing frame B22 of the printing section B, for conducting the printing operation in the printing section A the fluid cylinder A29 of the printing block A is so operated that the printing frame A22 and, in turn, the rotary screens A14 are lowered to the printing operation position. Coincidentally, actuation of the first clutch AMI of the printing section A and disengaging of the second clutch AM2 are effected, whereby the rotary screen A14 of the printing section A is driven and rotated at a speed synchronized with the travelling speed of the printing belt 4. Thus, the printing operation is continued by the printing section A.

While the printing operation by the printing section A is being carried out, a paste-receiving saucer is inserted below each rotary screen B14 of the printing section B, and washing of the screen, squeegee and dyestuff pump of the section B and other operations necessary for the next printing operation are carried out.

The above-mentioned procedures are repeated, and the printing operation can be continued by printing sections A and B alternately. Accordingly, in the rotary printing machine of this invention, various operations causing loss of time in the conventional rotary screen printing machines can be completely accomplished without interruption of the printing operation. According to the inventors experience, where a design of five colors is printed upon a material of 8,000 m length with four color combinations, each being 2,000 m length, in the conventional rotary screen printing machines at least 30 minutes are required for changing the color combination after every 2,000 m length of material is printed, and if the printing is conducted at a rate of 40 m/min, it takes 4 hours and 50 minutes total to accomplish the printing. Thus, the efficiency is about percent. In contrast, with the rotary screen printing machine of this invention, since all the operations required for changing the color combination, such as the screenwashing treatment, are completed without the interruption of the printing operation, the time required for such operations while the machine is not printing at all is at most 5 minutes. Thus, under the same printing conditions, the efficiency can be increased to about 93 percent in the rotary screen printing machine of this invention.

11. Case where the printing operation is conducted by employing printing sections A and B coincidentally:

In the rotary screen printing machine of this invention, the printing operation may be perfonned also by using the printing sections A and B coincidentally. In this case, in the printing sections A and B, actuation of fluid cylinders A29 and B29 and switchover of first clutches AMI and BMI and second clutches AM2 and BM2 are effected in a parallel manner. Thus, by employing all the rotary screens of printing sections A and B there can be obtained a multi-colored printing, for instance an eight-colored printing, as is illustrated in FIGS. 1 and 2.

Operation of each printing section is controlled by an electric circuit, for instance, as illustrated in FIG. 5.

In the circuit diagram of FIG. 5, symbol NFB designates a non-fuse circuit breaker, and CS and SS designate change-over switches. Symbols PB, CR, TR and RF designate a push button switch, a relay, a transformer and a rectifier, respectively. Symbols RA, RB, Ra and Rh each designate a protective resistance. MS and CL designate a magnetic switch and an overload relay, respectively. SOL A and S01 B designate solenoid valves A and B for actuating a fluid cylinder. Symbols AMI, BMl, AM2 and BM2 each to designate a magnetic clutch, and PM represents a pilot motor.

a. When a push button swich FBI is closed it energizes an exciting circuit for a realy CR0, and the relay CRO is actuated. At this point, it is necessary that the contact CRI in the circuit of the delay CRO should be in closed, namely CRI should be actuated (the driving speed of the belt is maintained at the lowest level). Open contacts CR and CR1 in the circuit of a switch MSI are closed to actuate the magnetic switch MS], whereby the main motor M is driven. b. When a switch 881 is closed to complete an exciting circuit for a relay CR4, the relay CR4 is actuated and in turn, the magnetic clutch AM]. is also actuated. As a result, the screens A14 are driven in synchronism with the printing belt. When a push button switch PB4 is closed to complete in an exciting circuit for a relay CR8, the relay CR8 is actuated to open contact CR8 in a circuit SOL A and cause a fluid cylinder A29 to lower the printing frame A22. in an exciting circuit for a relay CR5, by closing switch SS2, the relay CR5 is actuated, and in turn, a magnetic clutch IBM! is also actuated. As a result, the screens BM aredriven in synchronism with the printing belt. In an exciting circuit for a relay CR9, by closing a push button switch PBS, the relay CR9 is actuated, whereby in a circuit SOL B the open contact CR9 is closed and SOL B is actuated to cause a fluid cylinder 829 to lower the printing frame B22.

Magneticclutches AMI and BMll, or solenoid valves SOL A and SOL B, may be actuated coincidentally, or they may be actuated separately.

c. Whena stopping push button BBS provided in the exciting circuit for the relay CRO is pressed, energization of the relay CRO is. ended, and each of open contacts CRO connected in parallel to relays CR8 and CR9 is opened. Thus, energization of relays CR8 and CR9 is stopped, and in turn, actuation of solenoid valves SOL A and SOL B is also stopped. (They are returned to the original posi tions by means of springs when flow of electric current stops.) As a result,-fluid-cylinders A29 and B29 are caused to lift printing frames A22 and B22.

d. When a change-over switch SS2 in an exciting circuit for a relay CR6 or a change-over switch SS4 in an exciting circuit for a relay CR7 is closed, ei-

ther the relay CR6 or CR7 is actuated, whereby a magnetic clutch AM 2 or BM2 is actuated.

Since closed contacts CR4 and CR8 or closed contacts CR5 and CR9 are connected in parallel to the exciting circuit for the relay CR6 or that for the relay CR7, when the magnetic clutch AM! is actuated or when the printing frame A22 is in the lowered position, it is impossible to actuate the magnetic clutch AM2. Similarly, when the magnetic clutch BM! is actuated or when the printing frame B22 is in the lowered position, the magnetic clutch BM2 cannot be actuated. Magnetic clutches AM2 and BM2 may be actuated either separately or coincidentally.

tact CR7 are connected in parallel to the circuit for the magnetic switch MSA or the circuit for the magnetic switch MSB, only when the printing frame A22 is lifted and the magnetic clutch AM2 is actuated can the motor A48 be driven. Similarly, only when the printing frame B22 is lifted and the magnetic clutch BM2 is actuated can the motor B48 be driven.

The motor A48 and the motor Bd8 can be driven either separately or coincidentally.

By using the above-described circuit, operation of printing sections A and B can be carried out so as to attain the objects of this invention. Incidentally, adjustment or control of the speed of the printing belt may be accomplished appropriately by means of both the push buttons FBI and PBS.

I claim:

l. A rotary screen printing machine comprising pulleys at opposite ends of the printing operation zone, at least one pulley being a driven pulley, a printing belt supported on and driven by said pulleys for supporting a material to be printed and transporting it to the printing operation zone, a plurality of rotary screens positioned above said belt in said printing operation zone, a squeegee member in the interior of each rotary screen for squeezing a printing paste or ink through the rotary screen onto the material to be printed, a first drive mechanism coupled to said rotary screens for driving the rotary screens at a speed synchronized with the speed of the printing belt, said machine having in said printing operation zone a plurality of printing sections independent of each other, each of said printing sections including at least one of said rotary screens, a printing frame supporting said rotary screen and a lift mechanism for moving said printing frame vertically and operable independently of the lift mechanisms for the other printing sections, whereby the rotary screen of one printing section can be in the printing operation position, and the rotary screen of other printing section can be at a position raised from the printing operation position, and the printing operation can be conducted by less than all of the printing sections while the parts in the raised printing section are prepared for printing.

2. A rotary screen printing machine as claimed in claim 1, further comprising means associated with each rotary screen comprised of a bearing device on which each of the rotary screens is rotatably mounted, a supporting member on which said bearing device is mounted, a supporting shaft on which one end of said supporting member is pivotally mounted, the other end of said supporting memberbeing attached to said lift mechanism, a screen gear on the rotary screen, an idle gear on said supporting shaft engaged with said screen gear, a screen driving gear engaged with said idle gear, a second drive mechanism independent of said first drive mechanism, and means alternatively connecting said screen driving gear with said first drive mechanism and said second drive mechanism, whereby when the rotary screen of one section is in the printing operation position, said rotary screen can be driven by the first drive mechanism and the rotary screen of other printing block is at a position raised from the printing operation position and can be driven by the second drive mechanism.

3. A rotary screen printing machine as claimed in claim 2, wherein in each of the printing sections said lastmentioned means comprises a screen driving shaft, a gearing mechanism coupled between said screen driving shaft and said screen driving gear, and means at the ends of said screen driving shaft forcoupling said screen driving shaft to said first and second drive means, respectively.

4. A rotary screen printing mechanism as claimed in claim 3 wherein the means for connecting the screen driving shaft to said first drive mechanism is a first clutch mechanism at one end of said screen driving shaft, and said means for connecting the screen driving shaft to the second drive mechanism is a second clutch mechanism, said first drive mechanism comprising a gearing mechanism coupled to one of said pulleys for said belt for transmitting the rotation of said pulley, and a drive shaft coupled between said gearing mechanism and said first clutch mechanism for transmitting the rotation of said drive shaft through the first clutch mechanism to said screen driving shaft.

5. A rotary screen printing machine as claimed in claim 2 in which said screen gear is on one end of said rotary screen, and said machine further comprises a further screen gear on the other end of said rotary screen, a shaft rotatably mounted on said lifting device, and first spur gear fixed on one end of said shaft and engaged with said first-mentioned screen gear, and a second spur gear on the other end of said shaft engaged with said further screen gear.

6. A rotary screen printing machine as claimed in claim 2, wherein in each of said printing sections said lift meachanism comprises a vertical member on which said supporting member is mounted, said verticaly member being coupled to said printing frame, and a fluid pressure actuated means coupled to said vertical member for raising and lowering said printing frame and said vertical member.

7. A rotary screen printing machine as claimed in claim 6 in which said squeegee member is mounted on said printing frame and positioned within said rotary screen so that when the rotary screen is in contact with the material to be printed the blade of said squeegee member is in contact with the inner surface of the rotary screen, and when the rotary screen is in the raised position, the blade of the squeegee member is spaced from the inner surface of the rotary screen.

8. A rotary screen printing machine as claimed in claim 2 in which there are a plurality of rotary screens in each printing section each having an associated squeegee member, bearing device, supporting member,

screen gear, idle gear and screen driving gear.

Patent Citations
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3834309 *Sep 5, 1972Sep 10, 1974Zimmer PRotary screen printer with programmable screen interrupt
US3921522 *Apr 8, 1974Nov 25, 1975Zimmer PeterDevice for the printing of long repeat distance designs
US3941053 *Sep 27, 1973Mar 2, 1976James A. BlackPrinting press
US3965816 *Jul 15, 1974Jun 29, 1976Mitter & Co.Drive for rotary screen printer utilizing the roller squeegee
US3990363 *Nov 16, 1973Nov 9, 1976Stork Amsterdam N.V.Method and device for printing a web or a rectangular piece of material
US4114534 *Oct 6, 1976Sep 19, 1978Maschinenfabrik Peter Zimmer AktiengesellschaftControl system for rotary printing screens
US4771690 *Apr 24, 1987Sep 20, 1988Ernst W. Dorn Company, Inc.Screen printing apparatus for limited flexibility stock
US4909143 *Oct 7, 1988Mar 20, 1990Stork Brabant B.V.Multicolor, rotary screen printing machine and a stepped variable gear drive from a machine of this type
US4957044 *Jun 19, 1989Sep 18, 1990Cronin John VDouble sided screener for printed circuit boards
US5036759 *Oct 24, 1990Aug 6, 1991Gali Internacional, S.A.Installation for printing fabric pieces
US5265531 *Aug 27, 1991Nov 30, 1993John CroninReciprocally shuttled double sided screener with tiltable print squeegee
EP0805024A2 *Apr 9, 1997Nov 5, 1997Stork MBK GmbHRotary screen printing machine for printing large images
Classifications
U.S. Classification101/119, 101/116, 101/189
International ClassificationB41F15/10, B41F15/08
Cooperative ClassificationB41F15/10
European ClassificationB41F15/10