LABEL PRINTER

Abstract: A label printer (1) of the type including two printing devices (2.3) which can issue a label (10) and record paper (29) adjacent each other with printed faces thereof directed forwardly is realised by a specific arrangement of two printing devices and two supply devices without increasing the overall size of the printer. The label printer comprises a first printing device (2) including a first print head (6) mounted for reciprocal pivotal motion and for engagement with an upper face of a first platen (4), a second printing device (3) located within the same vertical planes and generally below the first printing device and including a second print head (9) mounted for reciprocal pivotal motion and for engagement with a lower face of a second platen (7), a first supply means (12) located behind the first printing device (2) for holding a carrier sheet (11) in the form of a roll to which a plurality of labels are applied and for supplying the carrier sheet (11) to the first printing device (2) with the labels (10) directed upwardly, and a second supply means (3) for holding a record paper (29) in the form of a roll with a printing face thereof directed outwardly and for supplying the record paper (29) to the second printing device (3) with the printing face of the record paper directed, downwardly.

Description: This invention relates to a label printer for printing a label and issuing the label after printing, and more particularly to a label printer which includes two independent printing devices therein. Label printers which include two different printing devices therein have been already provided. In one such arrangement, described in Japanese Utility Model 59-15930, one of the two printing devices is provided for printing on a label while the other printing device is provided for printing on record paper in the form of a web such as a receipt or a journal paper. Label printers of such a construction eliminate the necessity to exchange, in use, an object for printing such as a label each time the object for printing is to be altered. For example, when a receipt is to be printed just after a label has been printed, it is not necessary to load the receipt as well as the label. This is convenient for an operator and will quicken intended printing. Now, problems of such prior art will be described. The prior art label printer includes two independent printing devices, naturally it also includes two independent objects for printing such as a label and record paper. Normally, those objects for printing are each held in the form of a roll. However, those objects for printing have a large volume and thus occupy a wide space within the printer. Accordingly, it is a drawback that the size of the entire printer must be large accordingly. Further separate motors are provided for the individual printing devices as means for independently driving the printing devices. Accordingly, it is also a drawback that two motors are required and motion transmitting mechanisms are therefore complicated. This tends to further increase the overall size of the printer. U.S Patent Specifications 4 011 811 and 4 240 862 each disclose combined printing systems for printing boarding passes and baggage tags at airline terminals. In each case the printing operations are arranged alongside and therefore occupy considerable space. DE-C-373 991 discloses a manually operated ticket issuing and counting device comprising two ticket supply rolls arranged alongside and a clutch for selectively engging the first and second rolls with a manually operatable one-direction drive shaft. In summary, therefore, the prior art provides a a label printer, comprising: a first printing device including a first print head mounted for reciprocal pivotal motion toward and away from engagement with a face of a first platen; a second printing device including a second print head mounted for reciprocal pivotal motion toward and away from engagement with a face of a second platen; a first carrier sheet supply means located adjacent said first printing device for holding a carrier sheet in the form of a roll to which a plurality of labels are applied, and supplying the carrier sheet to said first printing device with the labels orientated for printing and dispensed at a first port, and a second supply means for holding a record paper in the form of a roll with a printing surface, and supplying the record paper to said second printing device with the printing surface of the record paper correctly orientated for printing by said device and dispensed at a second port. It is a first object of the present invention to provide a label printer of the type including two printing devices wherein a mechanism for transmitting a motion to the printing devices can be simplified. It is a second object of the invention to provide a label printer of the type including two printing devices wherein contents of printing on print media so as a label or record paper can be observed in a natural posture of an operator when they are issued. It is a third object of the invention to provide a label printer of the type including two printing devices wherein the overall size thereof is reduced. Accordingly the invention is characterized by first and second one-way clutches for transmitting rotation in opposite directions to a drive shaft, and a bi-directional motor for alternatively driving said first and second platens respectively via said one-way clutches. In this arrangement the mechanism for transmitting motion to the printing devices can be simplified. Particularly where the two one-way clutches are disposed in a coaxial relationship with a rotary shaft of the motor, the motion transmitting mechanism can be further simplified and the overall size of the printer can be reduced accordingly. The invention will now be described, by way of illustration only, with reference to the accompanying drawings, wherein:- Figure 1 is a perspective view of an entire printer illustrating a preferred embodiment of the present invention; Figure 2 is a side elevational view of the printer of Figure 1; Figure 3 is a side elevational view illustrating a motion transmitting route for driving a first platen and a take-up shaft; and Figure 4 is a side elevational view illustrating another motion transmitting route for driving a second platen. The printer shown includes a frame 1 in the form of a housing. A first printing device 2 and a second printing device 3 are located within the frame 1 such that the first printing device 2 is located superior to the second printing device 3 but relatively displaced rearwardly therefrom. The first printing device 2 includes a first platen 4 and a first thermal head 6 which serves as a first print head. The first thermal head 6 is mounted for reciprocal pivotal motion on a support shaft 5 and normally contacts an upper face of the first platen 4. Thus, the first thermal head 6 can be pivoted upwardly away from the first platen 4. The second printing device 3 includes a second platen 7 and a second thermal head 9 which serves as a second print head. The second thermal head 9 is mounted for reciprocal pivotal motion on a support shaft 8 and normally contacts a lower face of the second platen 7. Thus, the second thermal head 9 can be pivoted downwardly away from the second platen 7. A supply shaft 12 serving as a first supply device is located up stream of the first printing device 2 and is mounted for rotation on the frame 1. A carrier sheet 11 in the form of a roll is carried on the supply shaft 12 and has a large number of labels 10 applied in an equidistantly spaced relationship thereupon. An upwardly open hopper 14 serving as a second supply device is fixedly located between the first and second printing devices 2 and 3. Record paper 13 in the form of a wound roll is placed in the hopper 14 with a printing face 13a thereof directed outwardly. A label detaching member 16 for bending the carrier sheet 11 at an acute angle to detach a label from the carrier sheet 11 is located forwardly of the first platen 4. The label detaching member 16 is secured to the frame 1. A take-up shaft 15 is supported for rotation on the frame 1 between the supply shaft 12 and the hopper 14. A torque limiter not shown is incorporated in the take-up shaft 15. The torque limiter allows slippage between the take-up shaft 15 and a support shaft 15a on which the take-up shaft 15 is supported when a load higher than a predetermined level is applied. The carrier sheet 11 after passing the label detaching member 16 is wound onto the take-up shaft 15. A bi-directional motor 17 for driving the first platen 4, the second platen 7 and the take-up shaft 15 is carried on a side wall of the frame 1. A pair of one-way clutches 19, 21 are mounted on a rotary shaft 18 of the motor 17. The one-way clutch 19 transmits counterclockwise rotation of the rotary shaft 18 while the other one-way clutch 21 transmits clockwise rotation of the rotary shaft 18. A pulley 20 is connected to the output side of the one-way clutch 19 while another pulley 22 is connected to the output side of the other one-way clutch 21. A further pulley 23 is directly connected to an end of the first platen 4 while yet another pulley 24 is directly connected to an end of the take-up shaft 15. A timing belt 25 extends between and around the pulleys 23, 24 and the pulley 20 of the one-way clutch 21. An additional pulley 26 is directly connected to an end of the second platen 7, and another timing belt 27 extends between and around the pulley 26 and the pulley 22 of the one way clutch 21. It is to be noted that a label issuing port 28 is provided at a portion of the frame 1 at which a label 10 is issued, and a discharging port 29 is provided at another portion of the frame 1 at which the record paper 13 is discharged. With the construction described above, the first thermal head 6 prints on a label 10 on the first platen 4 and the second thermal head 9 prints on record paper 13 on the second platen 7 in response to a printing signal. Then, the motor 17 is rotated by a predetermined amount in the counterclockwise direction. This angular rotation is transmitted to the platen 4 and the take-up shaft 15 via the one-way clutch 19 and the timing belt 25 as seen in Figure 3. Consequently, the carrier sheet 11 is wound onto the take-up shaft 15 while the label 10 is detached from the carrier sheet 11 by the label detaching member 16 and is issued. In this instance, the winding speed of the carrier sheet 11 imparted by the take-up shaft 15 is not higher than the feeding speed of the carrier sheet 11 the first plate 4. This is because if a load higher than a predetermined level is applied against the turning force of the take-up shaft 15, the torque limiter incorporated in the take-up shaft 15, the torque limiter incorporated in the take-up shaft 15 will operate. Accordingly, slippage of the carrier sheet 11 at the first printing device 2 is prevented. When the motor 17 is rotated in the clockwise direction, this rotation is transmitted to the platen 7 via the one-way clutch 21 and the timing belt 27 as seen from Figure 4. Consequently, the record paper 13 is fed forwardly and thus issued. Since the first and second printing devices 2 and 3 are loacted within the same frame, the space of the printer in a widthwise direction can be utilized effectively. Further, since the two thermal heads 6, 9 do not interfere with each other when they are pivoted, it is possible to locate the two printing devices 2, 3, adjacent each other. Since, particularly in the present embodiment, the hopper 14 is located within a small space between the first and second printing devices 2 and 3, the space required for location of record paper 13 can be reduced. In addition, the supply shaft 12 is located rearwardly of the first printing device 2 where it will not interfere with locations of any other members. For these reasons, the overall size of the printer can be reduced. Further, a label 10 is issued horizontally with a printed face thereof directed upwardly. However, when the record paper 13 is issued, it is turned upqardly in such a manner that a printed face 13a thereof may be directed to the front due to its curling habit after it has passed the second printing device 3. Accordingly, the direction of issuing a label 10 at the label issuing port 28 and the direction of discharging the record paper 13 at the discharging port 29 will intersect each other with contents readily displayed. Consequently, as a label 10 and the record paper 13 are issued, they are issued at locations near to each other with their respective printed faces directed to the front. Accordingly, even with a printer of a reduced size, an operator can observe contents of printing on the label 10 and the record paper 13 while assuming a natural posture. In addition, the provision of the one-way clutches 19, 21 allows the single motor 17 to be used to drive both of the first printing devices 2 and the second printing device 3. Such common use of the motor 17 will reduce the number of motors to be employed in the printer and simplify the construction of the motion transmitting mechanism. Besides, as a result of such reduction of the number of motors and such simplification of the construction of the motion transmitting mechanism, the overall size of the printer can be further reduced.

Claims: A label printer comprising a first printing device (2) including a first platen (4) and a first print head (6) mounted for engagement with said first platen; a second printing device (3) including a second platen (7) and a second print head (9) mounted for engagement with said second platen; a first supply means (12) for holding a carrier sheet (11) in the form of a roll to which a plurality of labels (10) have been applied, and for supplying the carrier sheet (11) to said first printing device (2) with the labels (10) thereon for printing; a second supply means (13), for holding a record paper (29) in the form of a roll with a printing surface thereof correctly orientated for printing, and for supplying the record paper (29) to said second printing device (3) for printing; characterised by first and second one-way clutches (20.21) for transmitting rotation in opposite directions to a drive shaft (18); and a bi-directional motor (17) alternately driving said first and second platens (4.9) respectively via said one way clutches (20.21). A label printer according to claim 1 characterised in that said one-way clutches (20.21) are located in a co-axial relationship with the drive shaft (18) of the motor (17). A label printer according to claim 1 or 2 characterised in that the first printer (2) is mounted for reciprocal pivotal motion and for engagement with an upper face of said first platen (4), while the second print head (3) is mounted for reciprocal pivotal motion and for engagement with a lower face of said second platen (7), and in that said first supply means (12) is located rearwardly of said first printing device (2) while said second supply means (13) is located between said first and second printing devices (2) and (3). A label printer according to any of claims 1 to 3 characterised by a label issuing port (28) and a record paper discharging port, arranged such that the directions of issuing a label (10) from said label issuing port and a record paper from said record paper issuing port are such as to intersect adjacent an operator viewpoint. A label printer according to any of claims 1 to 4 characterised by a take-up shaft (15) for winding thereon the carrier sheet (11) after it has passed the first printing device (2) which is driven via a torque limiter by a driving force which cannot exceed a driving force for driving the first platen (4).

Inventors: KOMORI, YASUO
Applicants: TOKYO ELECTRIC CO., LTD.
Application year: 1990
Main classification: G07G5
IPC codes: G07G5, G07B5, B41J3, B41J15