JP2013075484A - Mountless label printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mountless label printer that can prevent coiling of the label paper around the platen roller when back feeding the mountless label paper by a simple mechanism.SOLUTION: The mountless label printer A that draws out the label paper 3' from the mountless label roll 3, prints the predetermined items in the label paper by a printing part 5, and issues the leaf shape label includes: a pressing member 8 that pulls back the label paper 3' to the mountless label roll 3 side, when back feeding the label paper 3' of a predetermined amount in the transport pathway of the label paper from the mountless label roll 3 to the printing part, and swings the label paper in the opposite direction to the reverse of the issuing direction of the label paper 3'; and a suppressing means 9 to suppress the rotation of the mountless label roll 3 when the label paper 3' is at least back fed.

Description

  The present invention relates to a mountless label printer that uses a mountless label roll wound in a roll as a label sheet.

In label printers that use label paper without mount as label paper, the adhesive surface (glue surface) on the surface opposite to the label paper print surface is in direct contact with the platen roller that feeds out the label paper. A non-adhesive (or easily peelable) surface treatment (for example, coating treatment) is applied to the outer peripheral surface of the platen roller, or the platen roller itself or the outer layer of the platen roller is made of a material that exhibits the above-described action. .
However, the effect of non-adhesiveness or easy peelability is not maintained permanently, and the effect is gradually lowered in long-term use. When a long time is required until the next label issuance after the previous label issuance, the mountless label sheet is continuously pressed by the pressure between the thermal head and the platen roller for a long time.
In this type of label printer, since the printing start position is in the vicinity of the leading edge of the label paper (a few millimeters on the roll side from the leading edge), the label paper is cut back to the printing unit side after cutting the printed label. When the platen roller is rotated backward so as to back-feed the label paper while the mount-less label paper is pressed by the pressure between the thermal head and the platen roller for a long time, the label paper is moved to the outer periphery of the platen roller. There is a risk of rotating while wrapping around the surface.
As shown in FIG. 5, the label paper 29 back-fed by the reverse rotation of the platen roller 28 is slackened in the vicinity of the upstream side of the platen roller as shown in FIG. The platen roller 28 rotates and winds as it is attached to the outer peripheral surface of the belt 28. When the label paper 29 adheres to the platen roller 28 and wraps around during the back feed, the label paper necessary for the next label issue cannot be fed out, and the label print cannot be issued.

In order to solve this problem, a pair of upper and lower drive rollers for conveying the label paper upstream of the platen roller is provided separately from the platen roller. When the label paper is back-fed, the drive roller is rotated in the reverse direction. A technique has been proposed in which tension is generated on the label paper on the upstream side of the roller, thereby peeling off the label paper attached to the platen roller (see, for example, Patent Document 1).
However, in this case, apart from the platen roller, a pair of driving rollers for sandwiching the label paper from above and below is provided at a position upstream from the platen roller, so that the structure is complicated and the cost is increased.

JP 2010-5943 A

  The present invention has been made in view of the above problems, and provides a mountless label printer that can prevent a label sheet from being wound around a platen roller when backfeeding a mountless label sheet with a simple mechanism. For the purpose.

  In order to achieve the above object, a mountless label printer according to the present invention draws a label sheet from a mountless label roll, prints a predetermined item on the label sheet by a printing unit, cuts and issues a sheet-like label In a less label printer, when a predetermined amount of the label paper is back-fed to the label paper moving path from the mount-less label roll to the printing unit including the platen roller and the thermal head, the label paper is moved to the mount-less label roll side. A pressing member that elastically swings back in a direction opposite to the direction in which the label paper is issued, and a suppression unit that suppresses rotation of the mountless label roll at least when the label paper is back-fed. Features.

The pressing member may be any of a plate-like member that is deformed by receiving an external force, or a roller member that is elastically oscillated with a return spring. As a specific example of the pressing member made of a plate-like member, for example, one in which one side portion of the plate member is fixed to the case and the free end of the other side portion is brought into contact with the label sheet can be considered. The pressing member may be any member that oscillates at least when the label paper back-feeds and pushes back the paper. When the label paper moves in the forward direction (issue direction), it does not come into contact with the label paper. In addition, the elastic swinging may be performed as described above only when the paper is back-fed.
Further, the label paper is bent and deformed by the movement of the label paper in the printing direction to accumulate a pullback force, and when the label paper is back-fed after cutting the print label, the label paper has a force to release the accumulated pullback force. You may make it join. In this way, in the forward direction in which the label paper is issued, the label paper is moved while accumulating force in the pressing means. Therefore, when the label paper is pulled out from the mountless label roll, It is possible to prevent an inertia force more than necessary due to the rotation from being applied to the printing unit. This is particularly effective for a mountless label roll having a large diameter. Then, a member for preventing an unnecessary force from being applied to the printing unit is used, and the stored force is released at the time of back feed, so that a special member is not required. That is, in this case, the pressing member can move in either the forward or reverse direction with respect to the label issuing direction.
Since the rotation of the label roll is suppressed at the time of back feed, the label paper acts to push the accumulated force back to the upstream side of the paper conveyance by the free end to release the accumulated force, so that the upstream side of the platen roller It is possible to prevent the paper from being wound around the outer peripheral surface.

Further, as the suppression means, any of a pressing member that elastically contacts the outer peripheral surface of the mountless label roll, a brake member that is mounted on the rotating portion of the mountless label roll, and the like may be used.
Specific examples of the brake member include, for example, a non-excitation electromagnetic brake, and when the label printer main body is turned off, when the label printer main body is turned on and waiting for label issuance, or back feed In this case, it is preferable to employ a spring-type non-excitation actuating electric brake in which a braking force is applied by a spring. That is, when the coil current is cut off, the armature is released and the disc is pressed against the end plate by the spring force and the brake is applied by friction. Therefore, the brake is always applied in the non-excited state. Therefore, only when the label sheet moves and issues in the forward direction, a current flows through the coil and the brake is released based on a signal for issuing the label sheet. In other words, even when waiting for label issuance or when the power of the label printer main body is OFF, the label roll is fixed and the label paper does not come loose.

  In addition, for example, the pressing member constituting the restraining means is attached to the shaft supporting the member that restricts the axial movement of the mountless label roll so that one side portion of the pressing member having a rod shape can be rotated. Then, the peripheral surface of the other side (free end) of the pressing member is brought into contact with the outer peripheral surface of the mountless label roll, so that the weight of the pressing member suppresses the rotation of the mountless label roll. In this case, the mountless label roll is not completely stopped. However, if the roll is held with a certain amount of force, the label paper between the print unit and the mountless label roll is held in a tensioned state by the restraining means during backfeed. Is done. Then, the pressing member slightly moves in the direction opposite to the label issuing direction against the tensioned label paper, so that the label paper is pulled back, and the label paper is placed on the upstream outer peripheral surface of the platen roller. It can prevent wrapping. In other words, it is more preferable for the restraining means to completely stop the rotation of the mountless label roll at the time of backfeeding because the label roll rotates when the pressing member comes into contact and does not form a deflection on the label paper. The force accumulated in the pressing member at the time of feeding may be released, and the rotation of the mountless label roll may be completely stopped as long as the force of acting to pull the label paper back to the upstream side is suppressed.

According to the above means, the label sheet is pulled out by the driving rotation of the platen roller constituting the printing unit, and predetermined items are printed on the label sheet by the thermal head. When the label sheet moves in the forward direction, the pressing member that comes into contact with the label sheet is also moved in the label sheet moving direction, and a pullback force is accumulated. Then, the label paper on which the predetermined matter is printed is cut into a sheet by a cutting means arranged on the downstream side of the printing portion, and a label is issued. After the label issuance, the label paper connected to the mountless label roll is back-fed to the printing unit side in order to set the next label printing start position near the leading edge of the label paper. When the label paper is back-fed, for example, if the paper is pressed by the platen roller and the thermal head for a long time, the paper is fed by the platen roller and the thermal head of the label paper when the paper is back-fed. The pressed portion rotates together with the platen roller, forms a bend on the upstream side of the platen roller, and winds up on the upstream side of the platen roller. This is particularly noticeable with label paper having an adhesive surface on the back side of the paper.
However, simultaneously with the start of the back feed of the label paper, the pressing member operates to release the accumulated pulling force and return to the original position, and when returning to the original position, the label paper is pushed back to the upstream side. Therefore, the label paper that is back-fed by the reverse rotation of the platen roller is held in a tension state to prevent the occurrence of slack. Thereby, when the label paper is back-fed, the label paper can be prevented from being wound around the platen roller.
Further, when the label paper is back-fed by reversely rotating the platen roller, since the rotation of the mountless label roll is stopped by the restraining means, it is ensured that the tension of the label paper is maintained by the pulling force of the pressing member. Can be performed stably.

In the mountless label printer of the present invention, the rotation of the mountless label roll is suppressed at the time of backfeed of the label paper, and the pressing member arranged in the moving path of the label paper with respect to the tensioned label paper has a label issuing direction. By swinging and swinging in the opposite direction, the label paper between the printing section and the mountless label roll is pulled back, and it is ensured that the label paper wraps around the outer peripheral surface of the platen roller when the label paper is back-fed. Can be prevented.
Moreover, since the pressing member is a simpler mechanism than the conventional case where a pair of upper and lower drive rollers for reverse rotation are provided, it is economical and can be easily attached to an existing product to wrap around the label paper. Prevention can be achieved. In the case of the driving roller, it is necessary to perform a non-adhesive surface treatment so that the adhesive surface does not adhere to the outer peripheral surface of the roller. Although there is a possibility of being caught by the roller, it is not caught by the pressing member because it is a pressing member that swings in the forward / reverse direction of the label sheet.

1 is a schematic side view showing an example of an embodiment of a mountless label printer according to the present invention. FIG. 4 is a partially enlarged view showing the operation of the pressing member, where (a) shows a state in which a pulling force is accumulated in the pressing member by forward drawing of the label paper, (b) shows a state in which the print label is cut from the label paper, c) is a state in which when the platen roller rotates backward and the label paper is fed back, the pressing member returns to the original position and the label paper is tensioned. The side view which shows the other example of a press member. The block diagram which shows the electric constitution of the printer provided with the electromagnetic brake as a suppression means which stops rotation of a base paperless label roll at the time of the back feed of a label paper. The side view which shows winding of the label paper in the conventional mountless label printer.

Hereinafter, an example of an embodiment of a mountless label printer according to the present invention will be described with reference to the drawings.
FIG. 1 schematically shows a mountless label printer A composed of a flat plate that can bend and deform a pressing member. A mountless label roll is provided in a case 1 and set in the roll loader 2. The label paper 3 ′ feed-out means 4, the printing section 5, and the cutting means 6 for cutting the printed label paper 3 ″ into a predetermined length are arranged at the front position in the feeding direction of the third label paper 3 ′. A label holding unit 7 that temporarily holds the printed label L that has been cut and sent is provided in front of the cutting unit 6, and further extends from the mountless label roll 3 set in the roll loading unit 2 to the printing unit 5. In the movement path of the label paper 3 ′, a pressing member 8 that is in contact with the label paper 3 ′ and elastically swings in the forward / reverse direction of movement is disposed. feed At this time, a restraining means 9 for stopping the rotation of the mountless label roll 3 is disposed in contact with the roll loading section 2, and the mountless label roll 3 is rotatably supported.
Note that an adhesive layer is applied in advance to the back surface of the label paper 3 ′, and the fed label paper 3 ′ is cut by the cutting means 6 to generate a single label that can be attached to the product. .
Further, since the pressing member 8 moves the label paper while accumulating force on the pressing member in the forward direction in which the label paper is issued, an excessive force is required when the label paper is pulled out from the mountless label roll. It can prevent joining to a printing part.

  The feeding means 4 for pulling out the label paper 3 ′ from the mountless label roll 3 set in the roll loading section 2 is a downstream composed of a pair of upper and lower rollers arranged in the vicinity of the upstream side of the label delivery opening 10 provided on the peripheral wall of the case 1. The sheet feeding means 4b on the side and the sheet feeding means 4a on the upstream side that also serves as the printing unit 5 arranged at a predetermined interval on the upstream side of the sheet feeding means 4b.

  The upstream sheet delivery means 4a also serving as the printing unit 5 includes a platen roller 5a positioned below (labeling side) the label sheet 3 'and a thermal head positioned above (printing side) the label sheet 3'. 5b, and the platen roller 5a and the lower roller in the downstream sheet feeding means 4b are driven and rotated by a motor. The thermal head 5b positioned above the label paper 3 ′ and the upper roller in the downstream paper feed means 4b are respectively connected to the lower side of the label paper 3 ′ (the lower roller and platen roller in the paper feed means 4b). 5a) and is biased downward so as to be attached, whereby the label paper 3 'can be stably delivered.

  The platen roller 5a of the printing unit 5 and the lower roller of the downstream paper feeding means 4b are coated with a release agent on the respective surfaces, and are applied to the side opposite to the printing surface of the label paper 3 '. The adhesive that has been applied is prevented from adhering so that the label paper 3 'can be fed smoothly. Note that the configuration in which the adhesive layer of the label sheet 3 ′ is difficult to adhere to the roller is not limited to the above configuration, and the roller itself or the outermost peripheral portion of the roller may be configured with an easily peelable member.

  The cutting means 6 that cuts the label sheet 3 ′ printed on the product information on the printing unit 5 and sent to the label delivery port 10 into a sheet of a predetermined length is sent horizontally from the label delivery port 10. It is composed of a pair of upper and lower movable blades 6a and a fixed blade 6b arranged so as to sandwich the label paper 3 '. The movable blade 6a advances and retracts toward the fixed blade 6b, whereby the label paper 3 'is cut by a shearing action. The leading edge of the label sheet 3 ′ cut by the cutting means 6 and connected to the mountless label roll 3 is back-fed to a position slightly protruding from the thermal head 5 b when receiving the next label issuing instruction. Thereby, at the time of the next printing, it is possible to print from the substantially leading end position of the label paper 3 '.

  The label holding unit 7 that temporarily holds the print label L cut by the cutting unit 6 in a standby state has a frame body 7b including a abacus ball-shaped contact member 7a on the outer surface of the case 1 via a fixed frame 11. Installed. The print label L sent to the label holding unit 7 is pasted on the product by automatic pasting by an pasting means (applicator) or by manual pasting by an operator.

The pressing member 8 disposed in the moving path of the label sheet 3 ′ from the mountless label roll 3 to the printing unit 5 is substantially the same width as the sheet width of the label sheet 3 ′ or a wide synthetic resin thin plate that is substantially S-shaped. A plate member (elastic plate) 12 that is bent and deformed, and one side portion 12a in the longitudinal direction of the plate member 12 is attached to a mounting portion 1 ′ projecting from the inside of the case 1 with a screw 12c. The free end of the other side portion 12 b is arranged so as to come into contact with the printing surface of the label paper 3 ′ drawn from the mountless label roll 3 and reaching the printing portion 5. The label sheet 3 ′ is supplied to the printing unit 5 in a substantially horizontal state by way of the plate member 12.
As a result, when the label paper 3 ′ is pulled out by driving of the feeding means 4 (the downstream paper feeding means 4b and the platen roller 5a), the plate member 12 in contact with the label paper 3 ′ moves the label paper 3 ′. Bending movement (bending deformation) from the position where the label paper 3 'was in contact toward the moving direction of the label paper 3', thereby pulling back the label paper 3 'to the plate member 12 in a direction opposite to the pulling direction. (Elasticity) is accumulated (see FIG. 1). It should be noted that the position of the free end of the plate member 12 that abuts on the label paper 3 ′ is determined by pulling out the label paper 3 ′ when the outer diameter of the mountless label roll 3 is reduced by issuing the label. ) Can be generated substantially in the same manner, for example, the angle at which the tangent line (label sheet feeding direction) in contact with the outer periphery of the mountless label roll 3 intersects the horizontal line direction of the label sheet 3 ′ passing through the printing section is approximately A position held at an acute angle is preferred.

In order for the plate member 12 constituting the pressing member 8 to bend and move (bend and deform) in the moving direction of the label sheet when the label sheet 3 ′ is pulled out, the roll loading unit is effective. The mountless label roll 3 set to 2 is required to stop without rotating in either the forward or reverse direction at least when the label paper 3 ′ is back-fed. That is, it is the suppression means 9 that allows the mountless label roll 3 to rotate during printing and stops the rotation during backfeed.
As the restraining means 9, as shown in FIG. 1, a rod-shaped pressing member 13 having a certain amount of weight is elastically brought into contact with the outer peripheral surface of the mountless label roll 3 by a spring member, and external force (label paper) If the external force does not act, the rotation of the mountless label roll 3 is maintained in a stopped state by the pressing member 13. In this case, the rotation is suppressed by the force of the spring member, and the rotation of the mountless label roll 3 is not completely stopped, but the plate member 12 and the label paper 3 ′ Is a force that exerts tension on the label paper 3 ′, and when the force stored in the plate member 12 is released, the label paper near the platen roller is pulled back upstream. Therefore, no label is attached to the upstream outer peripheral surface of the platen roller.
In other words, in the forward direction in which the label paper is issued, the label paper moves while the force is accumulated in the pressing means. Therefore, when the label paper is pulled out from the mountless label roll, an excessive force is applied to the printing unit. Since the accumulated force is released at the time of back feed by using a member for that purpose, the special member is unnecessary and the label paper near the platen roller is pulled back to the upstream side. As a result, no label is attached to the upstream outer peripheral surface of the platen roller. Further, since the plate member 12 is in contact with the printing surface (the surface opposite to the adhesive surface) of the label paper 3 ′ which is a non-adhesive surface, even if the number of times the label is issued is repeated, Is not attached to the label sheet 3 ', so that the label sheet 3' is not affected.

The pressing member 13 is attached by supporting one side portion of the rod-shaped pressing member rotatably on a shaft 14 disposed outside the roll loading unit 2 and the other side portion (free end side) of the pressing member. Rotating (tilting) and contacting the outer peripheral surface of the mountless label roll 3 around the shaft 14 so that the weight of the pressing member 13 acts as a load on the rotation of the mountless label roll 3.
The shaft 14 may be provided exclusively for attaching the pressing member 13, but as shown in FIG. 1, the mountless label roll 3 set in the roll loading unit 2 does not move in the axial direction (roll width direction). As described above, the movement restricting rod 15 is disposed in contact with the side end surface of the mountless label roll 3, but it may be attached using a shaft that supports the movement restricting rod 15.

The restraining means 9 that prevents the mountless label roll 3 from rotating in either the forward or reverse direction at least during backfeeding is not limited to the configuration of the pressing member 13, and the mountless label roll 3 is set. Brake means 16 may be attached to the roll loading unit 2. As a result, the roll is completely fixed at the time of back feed, so that a stronger tension state can be generated in the label sheet 3 ′, and the plate member 12 tries to return to the tensioned label sheet 3 ′. The label sheet near the platen roller 5a is pulled in the upstream direction, and the label sheet can be prevented from being wrapped around the outer periphery on the upstream side of the platen roller 5a.
The brake means 16 includes, for example, a non-excitation electromagnetic brake, and when the label printer body is turned off, the label printer body is turned on and the label printer body is on standby for label issuance or backfeed. It is preferable to employ a spring-type non-excitation actuating electric brake in which a braking force is applied by a spring in the brake. That is, when the coil current is cut off, the armature is released and the disc is pressed against the end plate by the spring force and the brake is applied by friction. Therefore, the brake is always applied in the non-excited state. Therefore, the brake does not act in the forward rotation direction in which the label sheet 3 ′ is pulled out from the mountless label roll 3, and when the label sheet 3 ′ is back-fed, the brake acts to rotate the mountless label roll 3. It is something to stop. For example, even when the label issuance of the day is completed and the label printer main body is turned off, the mountless label roll 3 is kept locked. 'Will not bend. That is, when the label is issued the first morning of the next day, the pressing member 8 and the label sheet 3 ′ come into contact with each other, so that when the label sheet 3 ′ back-feeds, the outer circumference on the upstream side of the platen roller 5a. It is possible to reliably prevent the label paper from being wound.

  Further, the pressing member 8 is not limited to the form constituted by the plate member 12 but may be a roll member. For example, as shown in FIG. 3, the roller 17a is rotatably attached to one side of the swing rod 17b, and the other side portion of the swing rod 17b is pivotally supported at a predetermined position in the case. A spring 17c is stretched at a substantially intermediate position between the shaft stopper of the swing bar 17b and the roller 17a, and the swing bar 17b moves in the moving direction of the label sheet 3 'by moving the label sheet 3' in the pulling direction. Thereby, a resilient force (retraction force) is accumulated in the spring 17c.

FIG. 4 is a block diagram showing an electrical configuration of the mountless label printer shown in FIG. 1, and the roll loading unit 2 includes a brake unit 16 (electromagnetic brake 27) as the suppression unit 9.
The configuration includes a CPU 18, a flash memory 19, a RAM 20, an operation unit 21, a display unit 22, a communication unit 23, a print control unit 24, a print issue unit 25, a cutter drive motor 26, and an electromagnetic brake 27.

The CPU 18 is a central processing unit that executes a program stored in the flash memory 19 and supervises the operation of the mountless label printer A.
The flash memory 19 is a read-only memory that stores a control program for the mountless label printer A, control data, and the like.
The RAM 20 has a work area for temporarily calling and processing data. Among them, a dot expansion area for expanding print data into dot data, and a call for calling and storing one format data from a label format file. There are a format area, a call product area for calling and storing product data, and the like.

The RAM 20 stores a label format file in which a label printing format is set, a product file in which various product data for label printing are set, and holds the product file and the format file even when the power is turned off. To be backed up by a battery.
The operation unit 21 is an input device for operating the main mount-less label printer A, and is a touch panel configured integrally with the display unit 22.
The display unit 22 is a liquid crystal display that displays various menu screens and data.
The communication unit 23 communicates with the host computer to exchange data.

The print control unit 24 controls the operation of the print issuing unit 25 based on a command from the CPU 18.
In this embodiment, the print issuing unit 25 pulls out the label paper 3 ′ from the mountless label roll 3 set in the roll loading unit 2, and prints information on the selected and designated product by the printing unit 5.
The cutter drive motor 26 drives the movable blade 6a of the cutting means 6 based on a command from the CPU 18 to cut the printed label sheet 3 ′ and issues a print label L.
The electromagnetic brake 27 is a spring-type non-excitation electromagnetic brake that stops the forward / reverse rotation of the mountless label roll 3 set in the roll loading unit 2. After the print label is cut and issued, the label paper 3 ′ The leading edge (the leading edge of the label paper connected to the mountless label roll 3 from which the printing label L has been separated) is back-fed for printing position alignment. During this back-feeding, a braking force is exerted by a spring in the brake, Stop the rotation of the mountless label roll 3. That is, the brake is applied except that the label sheet 3 ′ moves in the forward direction, and the mountless label roll 3 cannot rotate in either the forward or reverse direction.
The electromagnetic brake 27 stops forward / reverse rotation of the mountless label roll 3 set in the roll loading unit 2, and after cutting and issuing the print label, the leading end of the label paper 3 '(the mount on which the print label L has been cut off) The leading edge of the label paper connected to the less label roll 3 is back-fed for printing position alignment. During this back feed, rotation of the mountless label roll 3 is stopped by energization. Except when back feeding the label sheet 3 ', the power is cut off and the brake is not applied, and the mountless label roll 3 can be rotated in either the forward or reverse direction.

In the mountless label printer A configured as described above, when the label printing issuance is input from the operation unit 21 or the display unit 22, the feeding unit 4 (the downstream sheet feeding unit 4b and the platen roller 5a) is driven to drive the label sheet. 3 'is pulled out and product information selected and designated by the printing unit 5 is printed. For this printing, the label paper 3 'is pulled out from the mountless label roll 3, but when the label paper 3' is pulled out, the plate member 12 of the pressing member 8 arranged in the movement path of the label paper 3 'is shown in FIG. As shown in (a), the label sheet 3 ′ is bent and deformed in the same direction by the movement of the label sheet 3 ′ from the initial position (the position of the plate member (the position of the imaginary line) in the state before the start of printing). By this bending deformation, a pulling back force (elastic force) is accumulated in the plate member 12. When the label sheet 3 'is pulled out, the pressing member 13 of the restraining means 9 is in contact with the outer peripheral surface of the mountless label roll 3, but the pulling force by the feeding means 4 wins and the label sheet 3' is pulled out. .
When the printing of the selected and designated merchandise information is completed, the cutting means 6 operates to cut the printed label sheet 3 ′ and issue the print label L as shown in FIG.

After issuing the print label L, the tip of the label paper 3 ′ is back-fed by the reverse rotation of the sending means 4 in order to match the print start position in order to issue the next print label. It is pulled back to (slightly downstream position from the platen roller 5a). When the label paper 3 ′ provided with the adhesive layer on the back surface is continuously pressed between the thermal head 5a and the platen roller 5 for a long time, when the label paper 3 ′ back-feeds, Since the platen roll 5a rotates with a part thereof still attached to the platen roll 5a, the label sheet 3 'is conventionally wound around the platen roll 5a. However, when the label paper 3 ′ is back-fed, the label paper is pulled by the pulling force (elastic force) of the plate member 12 as the label paper 3 ′ moves upstream. Therefore, as described above, the platen roll 5a does not rotate while part of the label remains attached to the platen roll 5a, and the label paper 3 'does not wind around the platen roll 5a.
That is, when the label paper 3 ′ is back-fed, since the mountless label roll 3 is stopped from rotating by the pressing member 13 of the restraining means 9, as shown in FIG. The label paper 3 ′ positioned between the printing unit 5 and the printing unit 5 is held in a tension state by the pulling back force (elastic force) of the plate member 12. Accordingly, when the label paper 3 ′ is back-fed, it is possible to prevent the label paper 3 ′ from adhering to and wrapping around the platen roller 5a of the printing unit 5. If the restraining means 9 for stopping the rotation of the mountless label roll 3 is the electromagnetic brake 27, the brake is activated by energization, the rotation of the mountless label roll 3 is stopped, and the pressing member 8 (plate The member 12) acts to hold the label paper 3 'in tension.

The mountless label printer of the present invention is not limited to the illustrated embodiment, and can be changed as appropriate without departing from the spirit of the present invention.
(1) In the embodiment, an example in which a sheet feeding unit is arranged between the printing unit and the cutting unit is shown, and the back feed of the label sheet is also near the downstream side of the sheet feeding unit. For example, there may be a structure in which there is no sheet feeding unit between the printing unit and the cutting unit, and the leading end of the label sheet is pulled back to a position near the downstream side of the printing unit by back feed of the label sheet.
(2) In the embodiment, the plate member bent and formed in a substantially S-shape is shown as the pressing member. However, the present invention is not limited to this, and a linear plate member that bends and deforms by receiving an external force may be used.
(3) In the embodiment, as another example of the pressing member, the example in which the roller is rotatably attached to the swinging rod that is elastically swinged is shown. The label paper may be rotated in the direction in which the label paper is pulled out, the rotation is stopped in the reverse direction, and the swinging rod may be returned by the spring force in this state.
(4) In the embodiment, the spring type non-excitation electromagnetic brake has been described, but an excitation electromagnetic brake may be used. In this case, it is energized and braked when the label paper is back-fed, and the rotation of the mountless label roll 3 is stopped. In other cases, the electric brake is de-energized, so that there is no problem in issuing the label paper in the forward direction. Rotation may be suppressed by a pressing member that holds the mountless label roll 3 with the force of.
(5) In the embodiment, when the label is issued, that is, the label sheet 3 ′ moves toward the thermal head (the label sheet moves in the forward direction as the label sheet moves along with the printing on the label sheet). Although it has been described that the pulling force for pulling back the paper in the reverse direction is accumulated in the pressing member 8 so that the force is released when the label paper 3 ′ is back-fed, the present invention is not limited to this. A spring member that extends and contacts the label paper 3 'between the mountless label roll 3 and the printing unit 5 is provided and does not act when moving to the head, and acts only when the spring member back feeds. By doing so, the label sheet 3 ′ may be moved in the direction opposite to the sheet conveyance, so that the label is not wound around the upstream side of the platen roller 5a. In this case, the extended spring member may be pushed back to a position where it does not come into contact with the label sheet 3 ′ when the label sheet 3 ′ moves in the forward direction, for example, by operation of a solenoid. Even in this case, when the back feed is performed only by the movement of the spring member, the label sheet 3 ′ can be moved in the reverse direction of the sheet conveyance, so that the label is not wound around the upstream side of the platen roller 5a. it can.
That is, since there is no need to provide a roller member to be driven as in the prior art, a motor or roller member can be dispensed with and costs can be reduced. Further, in the case of the method of adding the driving roller member, there is a double problem that the label paper 3 ′ may be wound around the driving roller member. In the present embodiment, the spring member is used. In addition, the contact with the printing surface, which is the non-adhesive surface of the label paper, is brought into contact only when back-feeding, so that the spring member is not wound.

A ... Mountless label printer L ... Print label
2 ... Roll loading section 3 ... Mountless label roll 3 '... Label paper 5 ... Printing section
8 ... Pressing member 9 ... Suppression means 12 ... Plate member 13 ... Pressing member 16 ... Brake means (electromagnetic brake 27)

Claims (6)

In a mountless label printer that pulls out label paper from a mountless label roll, prints predetermined items on the label paper at a printing unit, and issues a sheet-like label,
When a predetermined amount of the label paper is back-fed to the label paper movement path from the mount-less label roll to the printing section consisting of a platen roller and a thermal head, the label paper is pulled back to the mount-less label roll side and the label paper A pressing member that elastically swings in a direction opposite to the issuing direction;
When the label paper is at least back-feeded, a suppressing means for suppressing rotation of the mountless label roll;
A mount-less label printer, characterized by comprising:   2. The mountless sheet according to claim 1, wherein the pressing member accumulates a pull-back force that contacts the label sheet and pulls the label sheet in a reverse direction by the movement of the label sheet accompanying printing on the label sheet. Label printer.   The pressing member is composed of a plate member that can be bent and deformed, one side of which is fixed, the free end side of the other side is in contact with the label sheet, and is deformed by movement of the label sheet in the printing direction. 3. The mountless label printer according to claim 1, wherein the pull-back force is accumulated to hold the label paper in a tensioned state by the pull-back force when the label paper is back-fed.   The mountless label printer according to any one of claims 1 to 3, wherein the suppressing means is configured by a pressing member that elastically contacts an outer peripheral surface of the mountless label roll.   The suppression means is a brake means attached to the rotating portion of the mountless label roll, and the brake does not act in the forward rotation direction in which the label paper is pulled out from the roll. The mountless label printer according to any one of claims 1 to 3, wherein the rotation of the less label roll is stopped.   5. The mountless label printer according to claim 4, wherein the pressing member constituting the suppressing means is attached to a shaft that supports a member that restricts the axial movement of the mountless label roll.

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