JPH0339895B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a label printer that prints labels to be attached to various products, and in particular, a cassette type label printer that is suitable for printing large quantities of various types of labels. Regarding label printers.

[Prior Art] In recent years, with the development of supermarkets and the like that sell a wide variety of products in large quantities, there has been a demand for label printers that can issue large quantities of many types of labels most suitable for each product. In response to this demand, a label printer has been developed that is equipped with multiple printing formats and is configured to automatically select and print the format according to the type of label (Japanese Unexamined Patent Publication No. 174294/1983). ).

In this type of label printer, generally, a label roll in the form of a roll of mount paper with labels pasted thereon is attached to the printer, and the labels are sequentially transferred and printed. Therefore, when a label runs out during printing or when changing the type of label, it is necessary to install a label roll. In this case, the tip of the label roll must be routed along a predetermined guide to attach it, which is a cumbersome process.Especially when there are many types of labels, replacement work increases, which is a factor in reducing work efficiency. I'm getting older.

In order to eliminate such inconveniences, the present applicant previously proposed a cassette type label printer (Japanese Patent Application Laid-Open No. 188821/1983). This allows labels and receipt paper to be easily replaced by storing the label roll and receipt paper in a cassette case.

[Problems to be Solved by the Invention] By the way, in the conventional cassette-type label printer described above, a platen roller is built into the cassette case, and paper is sandwiched between this and a thermal head provided on the main body side. I made it into a structure, so
This poses a problem in that the position of the platen roller within the cassette and the arrangement of parts around it are restricted, reducing the degree of freedom in design. Therefore, I thought about putting the platen roller outside the cassette, but
In this case, it became difficult to automatically set the label at the printing position when the cassette was replaced.

In such a printer, if the label is manually aligned to the printing position, it is difficult to accurately align the printing start position of the label to the predetermined printing position, and the label at the leading end of the label roll is wasted. There was a problem.

This invention was made against this background, and it does not have a printing head component such as a platen roller inside the cassette, and moreover, it automatically places a label in the predetermined printing position of the printing head when the cassette is replaced. To provide a cassette type printer which can be set and does not waste labels on the front end side of a label roll.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides for mounting a cassette containing label rolls in which labels are arranged in rows into a mounting section on the label printer main body side, and A cassette-type label printer that sequentially pulls out label rolls from a cassette and prints on the label with a printing head provided at a position away from the pulled-out position, comprising: a cassette detection means for detecting that the cassette is installed; type detection means for detecting the type of label on the label roll in the cassette that has been loaded; a feed-out transport means that feeds out the leading end of the label roll from the cassette and transports it to the print head; and a space between the cassette mounting section and the print head. label detecting means for detecting the position of the label on the label roll that is fed out from the cassette and transported; a measuring means for measuring length; and a judgment for determining whether the length of the label measured by the measuring means is the same as the regular length of the label type detected by the type measuring means. If it is determined by the determining means that they are the same, the label at the leading end of the label roll is set as the printing start position, and if it is determined that they are not the same, the printing start position is set at the label second from the leading end of the label roll. a printing start position determining means that sets the label as a printing start position; and when the cassette detecting means detects attachment of a cassette, the feeding and transporting means is controlled to feed out the leading end of the label roll, and the printing start position determining means The present invention is characterized by comprising a control means for stopping the label, which has been determined to be at the printing start position, at a predetermined printing position of the printing head.

[Function] According to the above configuration, when a cassette is installed in the mounting section of the printer main body, the cassette is detected by the cassette detection means, and the tip of the label roll is fed out from the cassette and transferred to the print head by the transfer means. It can be transported up to. At this time, by detecting the label position by the label detection means and by detecting the type of label by the type detection means, the tip of the label roll is determined by the calculation means based on the detection results. The print start position of the label on the side is determined, and based on the calculation result, the print start position of the label on the front end side of the label roll being transported can be stopped at a predetermined print position.

That is, by simply loading the cassette, the label roll can be automatically pulled out from the cassette, and the label printing start position at the leading end of the label roll can be automatically set at the predetermined printing position.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIGS. 1 to 8, 1 is a label printer main body, and 2 is a stand that supports the label printer main body 1. As shown in FIGS. A display section 5 and an operation section 6 are provided at the top of the front panel 3 of the label printer main body 1, and a switch section 7 is provided at the bottom of the front panel 3. Further, from the lower right end of the front panel 3, a label 8 affixed to a mount 8a is let out and taken up on a take-up reel 9.

FIG. 2 is a front view showing the configuration of the display section 5, operation section 6, and switch section 7. As shown in FIG.

First, the display section 5 displays each item to be printed on the label 8, including an area 5a for displaying the product name, product attributes, or various messages, and an area 5a for displaying the product name, product attributes, and various messages, as well as the manufacturing date, product weight, sales date, etc. Area 5b for displaying the product number and area 5c for displaying the product number and selling price.
Area 5d that displays the flight number, label type, etc.
It is made up of. Note that each area 5a to 5d is composed of a liquid crystal display.

The operating section 6 is composed of a flat keyboard 6a consisting of a numeric keypad and function keys, and a mode changeover switch 6b for changing the operating mode of the label printer. Note that the operation modes include a label issuing mode, an online mode, a master registration mode, and a date mode.

The switch section 7 includes a power switch 7a, a label rewind switch 7b, a label feed switch 7c, and a label detection sensor sensitivity adjustment knob 7.
d, and a connector 7e for connecting external equipment.

Next, the main parts of the label printer main body 1 and the cassette 30 will be explained with reference to FIGS. 3 to 8.

In these figures, 10 is a side plate fixed perpendicularly to the main body 1. The center and lower portions of the support plate 11 are fixed to the front surface of the side plate 10 in an overlapping manner (FIG. 6). Further, the upper part of the support plate 11 is bent forward into a step shape, and a cassette attachment plate 12 is fixed to this part in parallel with the side plate 10.

A stepping motor 13 is fixed to the back side of the side plate 10 where the side plate 10 and the support plate 11 overlap. Shaft 13a of stepping motor 13
protrudes forward of the support plate 11, the motor side gear 14 is fitted into the protruding part, and the shaft 13
The tip of a is the bearing 1 attached to the bearing plate 15.
6 (Fig. 3). Note that the bearing plate 15 is fixed to the front surface of the support plate 11 with screws. In addition, the shaft 13a of the stepping motor 13
A pulley 17 is fitted on the back side of the side plate 10 (FIG. 8) to drive a timing belt 18. The timing belt 18 rotationally drives the platen roller 21 of the printing section 20, and is stretched horizontally between the pulley 17 and the pulley 22, and has a gear 22a that shares a common axis with the pulley 22.
and a gear 2 that shares a shaft with the platen roller 21.
The platen roller 21 is rotationally driven via the platen roller 1a.

A thermal head 23 is disposed above and facing the platen roller 21, and is pressed against the platen roller 21 by a head pressing spring 24 that urges it downward. Then, printing is performed on the label 8 that is transferred between the platen roller 21 and the thermal head 23. This label 8 is
It is unrolled from the cassette 30, guided between a pair of upper and lower guide plates 25a and 25b, reaches a platen roller 21, and is unwound to the outside by the platen roller 21. Moreover, in the middle of the guide plate 25,
A label detection sensor 26 consisting of a light emitting element 26a and a light receiving element 26b is provided to detect the label 8. This detection is performed by utilizing the fact that the amount of light received increases at intervals between the labels 8 attached to the mount 8a in a row.

The printing section 20 is also provided with a lever 27 that rotates around a pin 27a, and when the upper end of the lever 27 is rotated counterclockwise, the support section 2 of the platen roller 21
1a rotates downward around the pin 21b, the platen roller 21 separates from the thermal head 23,
The heating element of the thermal head 23 can be cleaned. The support portion 21a is supported by a pin 21c that fits into a recess at the lower end of the lever 27.
It is stopped in the position shown in FIG. 3 or 4. Also,
There is a cutter 28 at the front upper part of the platen roller 21.
However, there is a guide plate 29 below the thermal head 23.
is provided.

Next, the cassette 30 will be explained with reference to FIG. 5 and the like.

The cassette 30 stores a label roll and feeds out the tip of the label 8 to the printing part 20, and includes a circular container-shaped storage part 30a having a bottom plate 30c, and a feeding part 3 provided at the bottom thereof.
0b.

The storage portion 30a is covered by a circular cassette lid 32 with a handle 31 attached to the center. When the cassette lid 32 is removed, a label roll set shaft 33 is provided at the center of the storage section 30a, protruding from the bottom plate 30c, and when the center hole of the label roll is fitted into the shaft 33, the label roll is mounted. The cassette lid 32 has a lock pin 33a protruding inward from the label roll set shaft 33;
A fixing plate 31a (FIG. 6) attached to the tip of the handle 31 is engaged and fixed. Further, a guide hole 42a' is provided at the center of the rear end surface of the label roll set shaft 33, passing through the bottom plate 30c.
A guide hole 42b' is provided near the feeding portion 30b.

The feeding section 30b includes a feeding roller 35,
It is composed of a pinch roller 36 that is pressed by the pinch roller 36, a guide plate 37 that guides the unreeled label, and a rewind guide plate 38.

The rear end of the shaft of the feeding roller 35 is connected to the cassette 3.
A gear 35a is fixed to this protruding portion. The gear 35a is a gear that meshes with the above-mentioned motor side gear 14 when the cassette 30 is attached to the main body 1, and thereby the feeding roller 35 is rotationally driven. On the other hand, a coil spring 35b that biases the roller 35 rearward is fitted into the front end of the shaft of the feeding roller 35. This means that even if the motor side gear 14 and the gear 35a do not mesh when the cassette 30 is attached to the main body 1, when the stepping motor 13 starts rotating,
This is to ensure automatic engagement.
Note that a manual knob 35c is attached to the front end of the feeding roller 35, so that the label 8 can be fed out manually. Further, the gear 35a is covered by a cover 35d.

The pinch roller 36 is rotatably fitted onto a shaft 36a, and both ends of the shaft 36a are supported by coil springs 36.
b in the direction of the feeding roller 35 (FIG. 8). Also, the bearing 36c of the shaft 36a
is formed in the shape of a long hole, and is configured such that the pinch roller 36 comes into contact with the feeding roller 35 and moves away from it. The reason for this will be explained later.

The label 8 transferred between the feeding roller 35 and the pinch roller 36 is moved to the upper and lower guide plates 37.
It is guided by a guide plate 37 consisting of a and 37b and transferred to the guide plate 25 on the main body 1 side. Note that a cutter 37c is formed at the tip of the upper guide plate 37a.

The unwinding guide plate 38 is opened and closed by a hinge provided at its lower end (FIG. 4 shows the closed state and FIG. 5c shows the open state), and the label 8
3 prevents it from escaping outward when it is unwound, and stores it in the storage section 30.

Next, the mounting portion 40 of the cassette 30 will be explained with reference to FIGS. 3, 6, and 8. First, the support plate 11 includes two support rods 41,
41 is erected and protrudes forward. Similarly, a guide rod 42b is provided near the gear 14,
The guide rod 42a is provided at the center of the cassette mounting plate 12. And the support rod 41,
41 and push the cassette 30 into the main body, the label roll set shaft 33 of the cassette 30
The guide hole 42a' provided in the guide rod 42
At the same time, the guide rod 42b is fitted into the guide hole 42b', and the cassette 30 is mounted in a predetermined position. In this case, the guide rod 42b
is provided near the gear 14, so that the cassette 3
0, the main body side gear 14 and the cassette side gear 35a are configured to mesh reliably. Furthermore, four spacers 43...
It is maintained at regular intervals by... Furthermore, the legs 30f of the cassette 30 fit into escape holes 44, 44 provided in the cassette mounting plate 12. Furthermore,
The bottom plate 30c is attracted and fixed by magnets 45, 45. Note that in this embodiment, the magnet 4
Although the cassette 30 is fixed by the levers 5 and 45, a locking mechanism may be provided to prevent the cassette 30 from being removed unless the lever is actuated.

Next, the cassette type discrimination mechanism will be explained. This determination is made by using a backing plate 50 (FIG. 7) fixed to the upper part of the bottom plate 30c of the cassette 30, and a four
The detection is performed using limit switches 51a to 51d. Here, the limit switch 51a~
51d is turned on when the backing plate 50 is detected and turned off when the backing plate 50 is not detected. Therefore, by appropriately arranging the backing plate 50, it is possible to detect whether a cassette 30 is attached or not and to detect 15 types of cassettes 30. That is, all limit switches 51a to 50
When d is off, it is detected that the cassette 30 is not installed, and the limit switch 5 is turned off.
15 due to the binary value (1 to 15) formed by 1a to 51d.
A cassette 30 containing different types of labels is detected.

Next, the electrical configuration of this embodiment will be explained with reference to FIGS. 9 to 11.

In these figures, 60 is a CPU.
The CPU 60 controls printing of the label 8 using a program stored in the ROM 61. 62 is
RAM, which provides a work area for the CPU 60 and an area for various registers to be described later, 63
is a communication interface for communicating with external equipment.

The print control unit 70 is connected to the CPU 60 via a printer interface 71. This printer interface 71 receives output signals from limit switches 51a to 51d for label type detection, and a light receiving element 26b of the label detection sensor 26.
is supplied with the output of Further, from the printer interface 71, a DC motor 72 that drives the take-up reel 9 and a stepping motor 1 are connected.
At the same time, a control signal is sent to the drive circuit 73 of the thermal head 23, and a drive signal DP is sent to the shift register 74 connected to the front stage of the drive circuit 73.
Print data DATA and clock CP are supplied to .

The drive circuit 73 is composed of an AND gate group 73a and a driver circuit 73b, and is adapted to drive the heating elements R1 to Rn of the thermal head 23 to perform dot printing. Further, the shift register 74 is connected via the printer interface 71.
The print data DATA supplied from the CPU 60 in 8-bit units is shifted and taken in, and is supplied to the AND gate group 73a.

Next, the label type table 80 stored in the ROM 61 will be explained with reference to FIG.

This table 80 has 15
Corresponding to each type of label, the length of the label 8 in the traveling direction including the gap part (hereinafter simply referred to as label length) L1, the length L2 of the label 8 from the front end to the stop position P, The length L3 from the rear end to the stop position P, the label feed length L4 when adjusting the sensitivity of the label detection sensor 26, the number Co of labels located between the thermal head 23 and the label detection sensor 26 (in this embodiment, the conventional Since the number of labels is counted when the front end of the label 8 is detected, in the case of FIG. 11, Co=4) and the print format number F are stored. In addition,
The lengths L1 to L4 are stored as the number of pulses of the stepping motor 13. Furthermore, the above lengths L3 and L4 are used for control when performing a sensitivity test of the label detection sensor 26 by feeding the label 8, but the sensitivity test process of the label detection sensor 26 is not directly related to this application, so explanation thereof will be omitted. Omitted.

In the above configuration, when the cassette 30 in which the label roll is set is mounted on the mounting section 40,
The limit switches 51a to 51d detect this, and the stepping motor 13 is driven to rotate in the normal direction under the control of the CPU 60. As a result, the feed roller 35 and the platen roller 21 are rotationally driven in conjunction with each other (see FIG. 12a), and the feed roller 35 feeds out the label 8. And label 8
As shown in b and c of the same figure, the platen roller 2 passes through the guide plate 25 and the label detection sensor 26.
1 and the thermal head 23.

In this case, the label transport speed by the platen roller 21 is slightly higher than the label transport speed by the feed roller 35. This results in
Even if the label 8 becomes loose between the feeding roller 35 and the platen roller 21, it can be returned to a naturally taut state. Also, if the tension is too high, the pinch roller 36 will cause the feed roller 3
Escape in the direction away from 5 to eliminate this tension. This is why the bearing 36c of the shaft 36a of the pinch roller 36 is formed into a long hole. In this way, the amount of label 8 to be transported is determined by the platen roller 21, and the label 8 is reliably transported by a predetermined amount.

On the other hand, if the stepping motor 13 is reversed,
The platen roller 21 and the feeding roller 35 are
The label 8 is rewound by rotating in the direction shown in the figure d. At this time, the guide plate 38 prevents the label 8 from escaping outward (to the right in the figure). By using this rewinding, it is not necessary to waste the label 8 located between the cassette 30 and the printing section 20 when the cassette 30 is removed.

Next, the operation when the cassette 30 is installed will be explained.

FIG. 13 is a general flowchart showing an overview of this operation. When the cassette 30 is loaded, the label 8 starts to be fed out after a certain period of time (step S1). After a while, when the first label 8 reaches the label detection sensor 26, the output of the sensor 26, which had been at "H" level, becomes "L" level. The output changes to "H" level again. Therefore, the length of the leading label can be measured by counting the number of pulses supplied to the stepping motor 13 during the passing period of the leading label (step S2). Note that when measuring the label length including the gap length as in this embodiment, the front end of the first label, that is, the sensor 26
It is sufficient to count the number of pulses from the time when the output changes from the "H" level to the "L" level until the front end of the second label is detected.

In this way, if the measured length of the first label is the regular length, it is set at the printing position of this label, but if it is not the regular length, that is, if the label is cut in the middle, the next label is set. Set the second label in the print position. This action is a step
S3 to S5. In addition, the regular length of the label, the length to the printing position, etc. can be found in the label type table 80.
Read and use the numerical values stored in the . Also, the label type at this time is the limit switch 51a.
Determined according to ~51d.

Next, details of the above operation will be explained with reference to the detail flowchart of FIG. 14.

In this flowchart, steps SP1 to SP14 are the label feeding process, steps SP15 to SP18 are for measuring the label length, step SP19 is for checking whether the first label length is normal or not, and steps SP13 and SP20 to 22 are for label printing position. This shows the action of stopping the machine.

First, in step SP1, it is checked whether all limit switches 51a to 51d are off, and when all are off, area 5a of display section 5 is checked.
``Cassette not loaded'' is displayed. On the other hand, if even one of the limit switches 51a to 51d is on, the CPU 60
The label type is determined from these on-patterns (step SP3). The CPU 60 searches the label type table 80 using this type as a key, and sets the numerical values L1 to L4, Co, corresponding to the attached label.
Read the print format number F and store it in RAM6.
2. Store in the register reserved on 2 (step
SP4).

After completing the above preparations, the CPU 60 sets a 3-second timer (step SP5), and displays in area 5a of the display section 5, ``The cassette has been set. Feed will start in 3 seconds.'' ( Step SP6). Then, after 3 seconds (step
SP7), set constants in counters SP, LC, and PC on RAM62. Here, the counter (stop counter) SP counts the feed amount in order to stop the feed when the feed on the label 8 exceeds a certain amount.
Each time one pulse is supplied to 3, the initial value PMAX (for example, 4000 steps) is counted down by 1. If the feeding process does not stop even after counting 4000 steps, it is determined that a level failure of the label detection sensor 26, a label jam, etc. has occurred, and an abnormality is displayed (step SP23).

The counter (label counter) LC counts the number of labels that have passed through the label detection sensor 26, that is, the number of times the front edge of the label has been detected, and the counter (pulse counter) PC counts the number of labels that have passed the label detection sensor 26. It counts the number of pulses supplied to the ping motor 13,
Both are set to initial value 0 (step
SP8).

Next, at step SP9, the message "Label feeding in progress" is displayed, and then at step SP10 to SP17
In this loop, the stepping motor 13 is stepped one pulse at a time to feed the label 8.

First, step SP10 sets stepping motor 1.
3 by one step, then step
At SP11, the stop counter SP is counted down and the pulse counter PC is counted up. If the stop counter SP is not zero (step SP12) and the pulse counter
If the PC is not L2 (step SP13), the stepping motor 13 is driven to continue feeding (steps SP10 to SP14) until the label detection sensor 26 detects the label 8 (step SP14).

Eventually, when the label 8 reaches the label detection sensor 26 and is detected (step SP14), the label counter LC is counted up by 1 (step SP15).
At step SP16, it is checked whether the label counter LC is 2 or not. If not 2 (in this case 1
), sets the pulse counter PC to "0" (step SP17), and returns to step SP10. This means that the preparation for measuring the length of the first label is completed.

If the value of the label counter LC is 2, this means that the leading edge of the second label has been detected. In other words,
The pulse counter PC contains the length of the first label as a count value. However, this label length also includes the interval between labels. When the label length is detected, the value of the pulse counter PC is stored in the label length register L, and the pulse counter PC is cleared (step SP18). In step SP19, the value L of the label length register L is determined to be the regular label length. Check whether it is within the range of L1±α (where α is a constant small value).

If the first label length L is within the normal range,
Return from step SP19 to step SP10 and continue rolling. Then, when the value of the pulse counter PC reaches the length L2 to the printing position, the process moves from step SP13 to step SP21, and the value of the label counter LC, that is, the number of labels that have passed the label detection sensor 26 (label front edge detection Check whether the number of times) has reached the value Co shown in FIG. 11a. LC＝
In the case of Co, the message "Label feed completed" is displayed in step SP22, and the feeding process is ended. On the other hand, when LC≠Co, control is transferred to step SP14 to continue feeding.

In step SP19 above, if the first label is not within the regular label length range, that is, if the first label is cut, the value Co
Up 1 (step SP20), step
Return to SP10 and perform the same process as above. This causes the second label to stop at the printing position.

The above is the operation when the cassette 30 is installed. On the other hand, rewinding is performed by cutting the printed and emitted label 8 with the cutter 28 and then pressing the rewind switch 7b. When this switch 7b is pressed, the stepping motor 13 is reversely rotated by a certain amount, and the label 8 can be rewound to the feeding opening of the cassette 30 (see FIG. 12d).

The above are the main operations of this embodiment. According to this embodiment, the following effects can be achieved.

Since the cassette 30 does not include components of the printing section 20 such as the platen roller 21,
The printing section 20 and the label feeding section 30b are completely separate. As a result, the inconvenience that print quality is affected by the mounting state of the cassette 30 is eliminated, and stable print quality can be obtained.

When the cassette 30 is installed, the first label is automatically transferred to a predetermined printing position regardless of the type of label contained therein, and the label becomes ready for printing. This makes label replacement work extremely easy.

Since the feeding roller 35 and the platen roller 21 work together, the label 8 can be rewound. Thereby, the label cut outside the printing section 20 can be rewound by the rewind switch 7b, and it is possible to prevent the label 8 from being wasted when replacing the label.

Compared to the conventional type in which a platen roller is built into the cassette 30, the degree of freedom in design is increased, and the amount of labels that can be stored is also increased. In other words, in conventional cassettes, the platen roller was in pressure contact with the thermal head attached to the outside of the cassette, so there were restrictions on the mounting position of the platen roller, which hindered design freedom in terms of space. . In this embodiment, since the platen roller 21 is placed outside the cassette 30, such restrictions are avoided.

If the first label that is fed out is cut in the middle, the next label is automatically set in the printing position, so when loading the cassette, you can check whether the first label was cut in the middle or not. ,
There is no need to check each time.

If the label detection sensor 26 is impaired,
If a paper jam occurs and the feed does not stop, it is forcibly stopped, so unnecessary feed can be stopped to a minimum.

Note that the following modifications are possible in this embodiment.

(1) In this embodiment, the label 8 is continuously rolled up without being peeled off from the backing paper, but the present invention is not limited to this, and the same applies to a label printer configured to peel the labels one by one from the backing paper. Can be applied. In this case, the label and the mount may be transported by a feed roller provided outside the thermal head.

(2) In this example, the length from the front edge of one label to the front edge of the next label was measured as the label length, but the length from the front edge to the rear edge of the label, that is, the label interval The actual label length that does not include the label length may be detected.
Further, although it is arranged to stop at the printing position based on the front end of the label, it may be stopped at the printing position using the rear end of the label as a reference. In this way, when detecting a label at the trailing edge of the label, it is necessary to detect the front edge and the trailing edge when measuring the length of the first label, but this is convenient for detecting label breakage. This is because if the label is not out, the next label should arrive after a short interval, and if it is not, it can be immediately determined that the label is out.

(3) In this embodiment, a limit switch is used to detect the type of cassette and then the type of label. Therefore, if for some reason the type of cassette and the type of label stored therein do not match, normal control will not be performed. Therefore, it may be possible to detect the label type by directly inspecting the label. For example, as mentioned above, the label length can be measured by the label detection sensor, so if the label length and label type have a corresponding relationship, the label type can be detected using the output of the label detection sensor. I can do it.

Note that instead of directly detecting the label type using the output of the label detection sensor, it may be configured to use the output to check whether the label type detected by the limit switch is correct. Further, the label type may be detected by forming a type detection mark on a part of the label or the mount in advance and detecting the mark.

(4) In this embodiment, a feed roller and a pinch roller are built inside the cassette. This structure is considered preferable, considering that it is easy to attach the cassette to the attachment section and that the tip of the label roll in the removed cassette is protected, but it is not limited to this structure. For example, if only one of the feed roller or the pinch roller is built into the cassette, and the other is installed in the mounting section of the label printer main body, then when the cassette is installed in the mounting section, there will be a gap between the feed roller and the pinch roller.
It is also possible to configure the label roll so that its leading end is sandwiched between the label rolls. However, in this case, it is necessary to devise ways to hold the tip of the label roll when the cassette is removed, and the structure for mounting the cassette.

[Effects of the Invention] As explained above, the present invention includes a cassette detection means for detecting that a cassette containing a label roll is mounted, and a type detection means for detecting the type of label on the label roll in the mounted cassette. means for feeding out the leading end of the label roll from the cassette and transporting it to the printing head; disposed at a predetermined position between the cassette mounting section and the printing head so that the leading end of the label roll is fed out from the cassette; a label detection means for detecting a label on a label roll to be transported; and a calculation for determining a printing start position on a label on the leading end side of the label roll based on a label detection signal of the label detection means and a detection result of the type detection means. means, when the cassette detection means detects attachment of the cassette, controls the feeding and transporting means to feed out the leading end of the label roll by a predetermined amount, and adjusts the printing start position of the label determined by the calculation means to the label printing start position. Equipped with a control means to stop the printing head at a predetermined printing position, simply by installing the cassette, the label roll is automatically fed out from the cassette, and the printing start position of the label on the leading end of the label roll is automatically set. The print head can then be set in place for printing.

Therefore, label replacement work can be made extremely easy, which is extremely advantageous when cassettes are frequently replaced, such as when many types of labels are used or when a large number of labels are printed.

Furthermore, since the label on the front end side of the label roll is stopped at the printing position, there is an effect that the label is not wasted.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the external configuration of a label printer according to an embodiment of the present invention, FIG. 2 is a front view showing the configuration of the display section, operation section, and switch section of the label printer, and FIG. 3 is a perspective view showing the configuration of the label printer. FIG. 4 is a side view showing the label printer in a state before the cassette 30 is installed, FIG. 5 is a view showing the configuration of the cassette 30, and FIG. In the figures, b is a side view, c is a front view showing the inside, Figs. 6 to 8 are views showing the state when the cassette 30 is installed, Fig. 6 is a side sectional view, and Fig. 7 is a plan view. , FIG. 8 is a plan sectional view, FIG. 9 is a block diagram showing the electrical configuration of the label printer, FIG. 10 is a block diagram showing the configuration of the print control section 70, and FIG. 11 is the configuration of the label type table. A conceptual diagram to explain the meaning of each numerical value, Figure 12 is a diagram to explain label feeding and rewinding, and Figure 13 is a general diagram to explain the operation of the same label printer when a cassette is installed. Flowchart FIG. 14 is a detailed flowchart for explaining the same operation. 1...Label printer body, 8...Label, 1
3...Stepping motor, 20...Printing section, 2
1...Platen roller (feeding transfer means), 2
6...Label detection sensor, 30...Cassette, 3
5... Feeding roller (feeding transfer means), 4
0... Mounting section, 51a to 51d... Limit switch (type detection means), 60... CPU (controlling means).

Claims (1)

[Scope of Claims] 1. A cassette containing label rolls in which labels are arranged in rows is attached to a mounting section on the label printer main body side, and the label rolls are sequentially pulled out from the cassette to a position away from the pulled-out position. A cassette-type label printer that prints on a label with a print head installed in the cassette includes cassette detection means for detecting that the cassette is installed, and type detection means for detecting the type of label on the label roll in the installed cassette. means for feeding out the leading end of the label roll from the cassette and transporting it to the printing head; disposed at a predetermined position between the cassette mounting section and the printing head so that the leading end of the label roll is fed out from the cassette; label detecting means for detecting the position of the label on the label roll being transported; measuring means for measuring the length of the label at the leading end of the label roll based on the output of the label detecting means; determining means for determining whether the measured length of the label is the same as the regular length of the label type detected by the type measuring means; printing start position determining means that sets the label at the leading end of the label roll as the printing start position if the labels are the same, and sets the second label from the leading end of the label roll as the printing start position if it is determined that they are not the same; When the cassette detection means detects that a cassette is attached, the feeding and transporting means is controlled to feed out the leading end of the label roll, and the label whose printing start position is determined by the printing start position determining means is transferred to the printing head. 1. A cassette type label printer, comprising: a control means for stopping printing at a predetermined position. 2. The cassette according to claim 1, wherein the control means controls the feeding and transporting means after a predetermined period of time has elapsed after the cassette detection means detects that the cassette is attached. formula label printer. 3. The type detection means detects the type of label from the label type information recorded on the cassette, and the cassette detection means detects whether the cassette is loaded when the type detection means detects the label type information. 3. A cassette-type label printer according to claim 1 or 2, characterized in that the printer detects whether the label printer has been loaded or not. 4. The label detection means detects the position and size of the label based on the label detection timing and the transport amount of the label roll, and the type detection means detects the size detected by the label detection means. 3. The cassette type label printer according to claim 1, wherein the type of label is determined based on the label type. 5. The label detection means detects the position and size of the label based on the label detection timing and the transport amount of the label roll, and the control means detects the first label from the detection result of the label detection means. Claims characterized in that, if the label is not of a regular length, the feeding and transporting means is stopped when the printing start position of the second label reaches a predetermined printing position of the printing head. The cassette-type label printer described in item 1.