PRINTER

Abstract: The present invention aims at providing a printing apparatus of a small size that facilitates replacement of a rolled paper, removal of a jammed paper, etc. and alleviates likeliness of a paper jam with a considerably simple structure. The printing apparatus comprises a rolled-paper holder (2), which is provided with a first holder (2b) for use in carrying out printing on a rolled paper (1), and a second holder (2a) for use in setting the rolled paper (1), wherein the rolled paper (1) is moved from the second holder (2a) to the first holder (2b) as a main body of the apparatus is shifted from a paper setting position to a printing work position, thereby facilitating the setting of the rolled paper (1) and removal of a jammed paper, since the rolled paper (1) can be temporarily supported by the second holder (2a) in order to provide a sufficient work space when replacing the rolled paper (1) or removing a jammed paper.

Description: The present invention relates to a printing apparatus for printing characters or figures on a rolled paper by using a printer head, and, more paiticularly, to a printing apparatus having a considerably simple structure, for which replacement of the rolled paper and removal of a jammed paper can be carried out easily, while decreasing incidents of paper jam. In most known printing apparatuses of that kind a printed output is of a definite format, and, upon completion of printing, it generally sends out the printed output with a paper transfer mechanism in a manner that a perforated line of a recording paper comes out of the apparatus, allowing the printed output to be cut along the perforated line. Accordingly, some apparatus have been proposed in recent years, in which a printed output is transferred to a discharge port by using a transfer means, etc. after it is cut while the printing is stopped for a moment within the apparatus, as shown in Fig. 13, in order to adapt printed output of an irregular shape (varied in length) and to avoid paper jams due to a consequent strain of the recording paper during the printing. Also JP-A 02 158 370 discloses such a printer comprising a platen roller for transferring recording paper across a printing head, a cutter for cutting recording paper and a discharge roller for feeding out a cut recording paper. Returning now to Fig.13, a numeral 51 in the figure represents a roll of paper, which is so arranged that it is cut in a predetermined length by a cutter unit 53, and transferred to a discharge port 55 by a presenter 54 after it is printed with a printer unit 52. Also, a numeral 56 represents a paper holder for supporting the roll of paper 51 rotatably, and numerals 57 and 58 are a roller and a printer head respectively, as they represent structural elements of the printer unit 52. With the above described structure of the prior art, a leading end of the roll of paper 51 held in the paper holder 56 needs to be inserted into a feeding port (not shown in the figure) of the printer unit 52 when the roll of paper 51 is reset in the printer unit 52 for replacement of the roll of paper 51, or after removal of a jammed paper, etc. In doing this task, however, the leading edge of the paper held in the paper holder 56 can not be inserted simply and easily into the feeding port of the printer unit 52, and the jammed paper occurred between the roll of paper 51 and the printer unit 52 can not be readily removed because of a very tight space between the roll of paper 51 and the printer unit 52 in the previous structure. There is a possibility that the paper is inadvertently rumpled or torn, if the roll of paper 51 could not be set easily in position. Also, there has been another fear that a part of the jammed paper is left behind in the printing apparatus, if the jammed paper can not be removed easily. They have been the cause to lead to another paper jam again. Widening the space between the roll of paper 51 and the printer unit 52 could clear this problem, but it would raise a new problem in which a dimensional reduction of the apparatus is restricted. Also, the structure of the prior art has frequently caused paper jams in the transfer means 54. Although there is a way to prevent it, in that the transfer means 54 is disused, and recording papers are freely dropped with their own weight, leading them to the discharge opening after printing, it poses a problem with the papers that fly out of the discharge opening by an impetus of the dropping. Furthermore, the structure of the prior art tends to cause the paper to stick to the surface of the roller 57 or the printer head 58 during a long stand-by time, or if it is used in an environment of high temperature, high humidity, low temperature, low humidity, etc. regardless of the stand-by period, so as to result in a failure of feeding the paper in the succeeding printing operation and to become liable to cause a paper jam. Also, there have been cases in which the paper transferring operation is impaired due to oxidation, corrosion, hardening of grease, etc. of components such as a gear, an axle, a bearing, etc. that constitute a paper transfer mechanism. There have also been impairments with an operation of a cutter mechanism having a similar component structure. The invention aims at providing a printing apparatus of considerably simple structure that reliably delivers a printed output to a discharge port without causing a paper jam, even for the printed output of an irregular shape (varied in length). The invention further aims at providing a highly reliable printing apparatus, which prevents a paper jam in a succeeding printing operation, and avoids an impairment to operation of the paper transfer mechanism and the cutter mechanism, even under such severe conditions as an extended stand-by time and use environment of high temperature, high humidity, low temperature, low humidity, etc. These objects are achieved by the features of claim 1 for a printing device and the features of claim 7 for a method for operating a transfer mechanism. Further embodiments are the subject-matter of dependent claims. The printing apparatus of the present invention is designed to move the recording paper toward a reverse direction after it be once moved toward a forward direction, and to drive the cutter, when a predetermined time is elapsed during a stand-by period. This effectively avoids the recording paper from being stuck completely to the roller or the printer head by temporarily freeing the paper which begins to stick, and, at the same time, prevents component parts of a paper transfer mechanism and a cutter mechanism from oxidation, corrosion, hardening of grease, etc., so as to avoid a paper jam. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a structural drawing depicting a brief construction of an example of a printing apparatus in its open position useful for understanding the present invention; Fig. 2 is a structural drawing depicting a brief construction of the same example in its closed position for the normal printing operation; Fig. 3A and Fig. 3B is a structural drawing depicting a brief construction of the same example in its intermediate position; Fig. 4A to Fig. 4D is a typical drawing depicting an operational flow of a printing apparatus of a first exemplary embodiment of the present invention; Fig. 5A to Fig. 5D is a typical drawing depicting an operational flow of a printing apparatus of a second exemplary embodiment of the present invention; Fig. 6A to Fig. 6E is a typical drawing depicting an operational flow of a printing apparatus of a third exemplary embodiment of the present invention; Fig. 7A to Fig. 7E is a typical drawing depicting another exemplar of an operational flow of a printing apparatus of a fourth exemplary embodiment of the present invention; Fig. 8A and Fig. 8B is a typical drawing depicting an operational flow of a printing apparatus of a fifth exemplary embodiment of the present invention; Fig. 9 is a perspective view depicting a construction of a printing apparatus not forming part of the present invention; Fig. 10 is an operational flowchart during a stand-by period of an exemplary embodiment not forming part of the present invention; Fig. 11 is an operational flowchart during a stand-by period of an exemplary embodiment not forming part of the present invention; Fig. 12 is an operational flowchart during a stand-by period of another exemplary embodiment not forming part of the present invention; and Fig. 13 is a structural drawing depicting a printing apparatus of the prior art. The present invention is described in more detail according to the accompanied drawings. Fig. 1 to Fig. 3B depict a brief structure of an example of a printing apparatus useful for the understanding of the present invention, where Fig. 1 shows a main body of the apparatus in its open position, Fig. 2 shows the same in its closed position, and Fig. 3A to Fig. 3B shows an intermediate position of the same. In the figures, a numeral 1 represents a roll of paper, which is axially supported by a roller shaft 9 as well as a paper holder 2 provided on a back surface of the main body of the apparatus, and paper is discharged via a cutter unit 4 after having been printed with a printer unit 3. Also, a recording paper 1a cut by the cutter unit 4 in a predetermined length falls toward a discharge port 6 through a guide unit 5 having a shape of a duct or a chute. The paper holder 2 is provided with a first holder 2b for securely supporting the roll of paper 1 while carrying out printing on the paper, and a second holder 2a for temporarily supporting the roll of paper 1 when the roll of paper 1 is replaced or a jammed paper is removed, wherein the roll 1 is rotationally or slidingly moved from the second holder 2a to the first holder 2b by a paper thruster 7 provided on a part of a housing for storing the main body of the apparatus, along with a movement of the main body being stored into the housing. Incidentally, a numeral 8 is a controller composed of a touch panel, a key switch, etc., and a printing operation on the paper is carried out in response to a command of the controller 8. An operation of the printing apparatus composed of the above structure is now described by referring to Fig. 1 to Fig. 3B. As shown in Fig. 1, a large space can be provided for replacement of the roll of paper 1 or removal of a jammed paper, if the roll 1 is positioned temporarily on the second holder 2a of the paper holder 2, so as to allow the work to be carried out very easily when inserting a leading end of the paper into a feeding port (not shown in the figure) of the printer unit 3, or removing the jammed paper in the printer unit 3. Also, when the roll of paper 1 is held on the first holder 2b of the paper holder 2 with the main body of the apparatus returned to the normal printing work position, as shown in Fig.2, a space between the roll 1 and the printer unit 3 is reduced substantially, since replacement of the roll of paper 1 or removal of the jammed paper need not be carried out in this position, so that a reduction in size is realized of a printer unit portion composed of the paper holder 2, the printer unit 3, the cutter unit 4, etc. Furthermore, as shown in Fig. 3A and Fig. 3B, the roll 1 positioned temporarily on the second holder 2a of the paper holder 2 makes a contact with the paper thruster 7 (Fig. 3A) when the main body of the apparatus is shifted from the paper setting position for the roll of paper 1 toward the normal printing work position, and the roll of paper 1 is disengaged from the second holder 2a to rotationally or slidingly move to the first holder 2b along a sloped edge of the paper holder 2 (Fig. 3B) when the main body is further shifted, so that the roll 1 can be restored into the position for carrying out printing with a simple return of the main body to the original position, thereby enabling a replacement of the roll of paper 1 and removal of jammed paper easily and in a short time. Hence, the above structure can prevent a paper jam caused by a working error during replacement of the roll of paper 1 and an incomplete removal of papers jammed in and around the printer unit. Although in the above example the main body of the apparatus is constructed so as to be openable on an axis at its lower end, this is not exclusive and the same effect is attainable by constructing it to be openable on an axis located at an upper end or at an either side of right or left side of the upper end. Also the above described example can take up a slack of the roll of paper 1, because a rotating direction and a moving direction of the roll of paper 1 in its rotational movement from the paper setting position to the printing work position are in a relationship of rewinding the roll of paper 1. An operation of a first exemplary embodiment of the present invention is described. Fig. 4A to Fig. 4D are typical drawings depicting an operation of a printing apparatus of a first exemplary embodiment of the present invention. In Fig. 4A to Fig. 4D, numerals 1c, 21, 22, 26 and 27 represent a recording paper, a stationary blade, a movable blade, a roller and a printer head, respectively. A normal printing operation is carried out by pressing the recording paper 1c against the printer head 27 with the roller 26 in rotary motion during printing while also transferring the paper simultaneously, followed by discharging the paper after it is cut with the stationary blade 21 and the movable blade 22. Fig. 4A depicts an initial condition of a stand-by period, Fig. 4B depicts a condition wherein the paper 1c is transferred in a forward direction after a predetermined time has elapsed during the stand-by period, Fig. 4C depicts a condition wherein the paper 1c is transferred in a reversed direction, and Fig. 4D depicts a condition wherein an automatic cutter is activated. The recording paper 1c is sent forward with a rotation of the roller 26, in Fig. 4B, and the recording paper 1c is returned backward with a reversed rotation of the roller 26, in the next Fig. 4C, so as to prevent the recording paper 1c from being stuck completely with the printer head 27 or the roller 26 by temporarily freeing the recording paper which begins to stick with them. In Fig. 4D, the movable blade 22 is activated, so as to protect component parts of an automatic cutter mechanism from oxidation, corrosion, hardening of grease, etc. The operation described above is able to prevent a paper jam caused by a complete stick of the recording paper 1c, which is liable to occur in case of a long stand-by period before a succeeding printing operation, or if it is used in an environment of high temperature and high humidity, etc. regardless of the stand-by time. In the above description, the forward direction is meant to be a direction to which the recording paper 1c is transferred during the printing operation, and it is the right side in Fig. 4A to Fig. 4D. The reversed direction is a direction opposite to the forward direction. Also, any spot located in the forward direction and any spot located in the reversed direction with respect to a basic position may be referred to as an upstream side and a downstream side respectively from now on. Although in the described exemplar operation of the present embodiment, the recording paper 1c is once transferred in the forward direction after the predetermined time is elapsed, and the cutter is activated following the transfer to the reversed direction, the same effect is also attainable by transferring the recording paper 1c once toward the reversed direction after an elapse of the predetermined time, and transferring back to the forward direction after the cutter has been activated. Fig. 5A to Fig. 5D are typical drawings depicting an operation of a printing apparatus of a second exemplary embodiment of the present invention. A letter A in the figures indicates a backside of a cutter. Fig. 5A depicts an initial condition of a stand-by period, Fig. 5B depicts a condition wherein the recording paper 1c is transferred in a forward direction after a predetermined time has elapsed during the stand-by period, Fig. 5C depicts a condition wherein the recording paper 1c is transferred in a reversed direction and stepped with a leading end of the recording paper 1c located at a position downstream of the backside of the cutter, and Fig. 5D depicts a condition wherein an automatic cutter is activated. The recording paper 1c is sent forward with a rotation of the roller 26, in Fig. 5B, and the recording paper 1c is returned backward with a reversed rotation of the roller 26, to a position where the leading end of the recording paper 1c does not exceed the backside of the cutter in the next Fig. 5C, so as to prevent the leading end of the recording paper 1c from being cut by a subsequent cutting operation, as well as a paper jam in an insertion port at the backside of the cutter during a paper transferring operation after the cutting. Hence, paper jams caused by a complete stick as described above can be prevented by temporarily freeing the paper, which begins to stick with the printer head 27 or the roller 26, by rotating the roller 26 forward and backward, in the same manner as the operation of the first exemplary embodiment, and also component parts of a paper transfer mechanism and an automatic cutter mechanism can be protected from oxidation, corrosion, hardening of grease, etc. Fig. 6A to Fig. 6E are typical drawings depicting an operation of a printing apparatus of a third exemplary embodiment of the present invention. Since Fig. 6A to Fig. 6D depict the same conditions as Fig. 4A to Fig. 4D in the first exemplary embodiment of the present invention, they are not described below. Fig. 6E depicts a condition where a recording paper 1c is transferred in the forward direction to the initial position (a condition in the start of a stand-by period), and a dispersion in position of the recording paper 1c after a series of the above operations can be deprived by transferring it in the forward direction in order to absorb a backlash in gears that constitute the paper transfer mechanism. It also has an effect of preventing paper jams in the same way as the first exemplary embodiment. A fourth exemplary embodiment of the present invention is described in the same manner by referring to Fig. 7A to Fig. 7E. Since Fig. 7A to Fig. 7D depict the same conditions as Fig. 5A to Fig. 5D in the second exemplary embodiment of the present invention, they are not described below. Fig. 7E depicts a condition where a recording paper 1c is transferred in the forward direction to the initial position (a condition in the start of a stand-by period), and a dispersion in position of the recording paper 1c after a series of the above operations can be decreased by transferring it in the forward direction in order to absorb a backlash in gears that constitute the paper transfer mechanism. As a matter of course, it also has an effect of preventing paper jams in the same way as the second exemplary embodiment. Fig. 8A and Fig. 8B are typical drawings depicting an operation of a printing apparatus of a fifth exemplary embodiment of the present invention. In Fig. 8A and Fig. 8B, the same component elements as those of Fig. 4A to Fig. 4D are assigned with the same reference numerals, and their description is omitted. Numerals 28, 28a and 29 represent a cutter housing, a paper exit of the cutter housing 28 and a paper discharge guide, respectively. Fig. 8A depicts an initial condition of a stand-by period, in which a slightly curled recording paper 1e is hanging by adhesion on the paper exit 28a of the cutter housing 28 after having been cut, and Fig. 8B depicts a condition where a paper advancing operation has been made after a predetermined time interval during the stand-by period after the cutting. The paper advancing operation after lapse of the predetermined time has a function of pushing out the adhering paper 1e. Accordingly, a printed recording paper after having been cut can be discharged, even if it is jammed within the apparatus. Fig. 9 is a perspective view depicting a structure of an example of a printing apparatus not forming part of the present invention, in which a numeral 1c is a recording paper, a numeral 27is a printer head for printing characters or figures on the recording paper 1c, a numeral 26 is a roller for transferring the recording paper by making a contact with the printer head 27, a numeral 31 is a stepping motor for rotating the roller 26, and a numeral 30 is a paper transfer gear for transferring rotary motion of the stepping motor 31 to the roller 26. The roller 26, the stepping motor 31 and the paper transfer gear 30 constitute a transfer means. Fig. 10 is an operational flowchart during a stand-by period in the same exemplary embodiment. When the printing apparatus is placed in a stand-by position, it waits for a predetermined time, and rotates the stepping motor 31 in the forward direction for a step of "N1" when the predetermined time has elapsed, in order to transfer the recording paper 1c in the forward direction. It then rotates the stepping motor 31 in the reversed direction for a step of "N2" to transfer the paper 1c in the backward direction. Finally, it rotates the stepping motor 31 in the forward direction for a step of "N3" to transfer the recording paper 1c in the forward direction before terminating the stand-by operation. In here, the forward direction is meant to be a direction shown by an arrow in Fig. 9, and the reversed direction is a direction opposite to it. The printing apparatus derived as above transfers the recording paper in the forward and the reversed directions in every predetermined interval during the stand-by period, and prevents the recording paper 1c from being stuck completely with the printer head 27 or the roller 26 by temporarily freeing the paper that begins to stick, so as to avoid a paper jam caused by an adhesion and to prevent grease used for the components constituting the paper transfer mechanism from hardening. The printing apparatus also provides an effect of avoiding disfigurement of characters in a beginning of the subsequent printing, since it absorbs a backlash that occurs in the paper transfer gear 30, by rotating the stepping motor 31 in the forward direction, in the reversed direction, and again in the forward direction. In this exemplar operation, although the stepping motor is rotated in the reversed direction again after having rotated in the forward direction when the predetermined time has elapsed during the stand-by period, the same effect is also attainable by rotating the stepping motor first in the reversed direction and in the forward direction thereafter. Also, a D.C. motor can be utilized in place of the stepping motor 31, as it is capable of performing the same function in combination with an encoder. Moreover, the recording paper may be transferred by providing a roller for transferring paper in addition to the roller 26, and delivering it with driving force of the motor. Fig. 11 is an operation flowchart during a stand-by period in another exemplary embodiment not being part of the present invention. A structure of the embodiment is identical to that of the exemplary embodiment, which is shown in Fig. 9. In the present embodiment, when a printing apparatus is placed in a stand-by position, it waits for lapse of a predetermined time, takes a measurement of a latest ambient temperature after the predetermined time has elapsed, and adjusts a further waiting time according to the temperature. For instance, it waits for a time of "T1" if the measured temperature is low, waits for a time of "T2" if it is normal, and waits for a time of "T3" if it is high. After that, it rotates a stepping motor 31 forward for a step of "N1" to transfer a recording paper 1c in the forward direction. It then rotates the stepping motor 31 backward for a step of "N2" to transfer the recording paper 1c in the reversed direction. Finally, it rotates the stepping motor 31 forward for a step of "N3" to transfer the recording paper 1c in the forward direction, and, terminates the stand-by operation. The printing apparatus derived as described above reduces electric power it consume in driving the stepping motor 31 for the stand-by operation, and minimizes a trace that is left behind on a surface of the recording paper 1c due to a friction between the printer head 27 and the recording paper 1c with the forward and the backward rotations of the stepping motor 31, by reducing a number of operations of the stepping motor 31 with an increase of the time of "T2", since it takes a longer time for the recording paper 1c to stick with the printing head 27 or the roller 26 when the ambient temperature is normal. The printing apparatus also has an effect of avoiding a paper jam caused by an adhesion and preventing grease used for the components constituting the paper transfer mechanism from hardening, as it prevents the recording paper 1c from being stuck completely with the printer head 27 or the roller 26 by temporarily freeing the paper that begins to stick, by increasing a number of operations of the stepping motor 31 with a decrease of the time of "T1" and "T2", since it takes relatively a shorter time for the recording paper 1c to stick with the printing head 27 or the roller 26 when the ambient temperature is either low or high. Although a determination of the ambient temperature is made for the three levels of low, normal and high, in this exemplar operation of the present embodiment, a better effect can be achieved if it is further divided into more levels. Fig. 12 is an operation flowchart during a stand-by period in a further exemplary embodiment. A structure of the present embodiment is identical to that of the exemplary embodiment, which is shown in Fig. 9. When a printing apparatus is placed in a stand-by position, it waits for lapse of a predetermined time, and, after the predetermined time has elapsed, it proceeds into any one of processes A, B or C, according to a previously memorized information of dispersion in a magnitude of movement of the recording paper 1c when the stepping motor 31 has rotated forward and backward. A magnitude of movement of the recording paper 1c disperses when the stepping motor 31 rotates forward and backward, because there are cases in which the recording paper 1c moves a different magnitude due to a variation in condition of finish of a roller 26 and a load on a transfer system of the recording paper 1c, even if the number of forward steps and the number of reversed steps of the stepping motor 31 are the same. There are three cases, i.e., a magnitude of movement is larger in the forward rotation, a magnitude of movement is larger in the backward rotation, and, magnitude of movements are same between the forward and the backward rotations. If a magnitude of movement of the recording paper 1c is larger in the forward rotation than in the backward rotation, the stepping motor 31 is rotated,forward for a step of "N1", followed by backward rotation for a step of "N1 + N2 + a", followed finally by forward rotation for a step of "N2". A magnitude represented by the letter "a" corresponds to dispersion in the movement of the recording paper 1c by the forward and the backward rotations of the stepping motor 31. Also, if magnitude of movements of the recording paper 1c are same in the forward rotation and in the backward rotation, the stepping motor 31 is rotated forward for a step of "N1", followed by backward rotation for a step of "N1 + N2", followed finally by forward rotation for a step of "N2". Also if a magnitude of movement of the recording paper 1c is larger in the backward rotation than in the forward rotation, the stepping motor 31 is rotated forward for a step of "N1", followed by backward rotation for a step of "N1 + N2 - a", followed finally by forward rotation for a step of "N2", and the stand-by operation is terminated The printing apparatus derived as described above provides an effect of preventing a paper jam due to adhesion of the recording paper, and avoids shifting of a starting position of printing in the subsequent printing operation after resumption from the stand-by state by moving the recording paper to its original position by varying a number of steps for the forward and backward rotations depending on a condition of finish of the roller and a load on the transfer system of the paper, when rotating the stepping motor 31 forward, backward and forward after lapse of a predetermined time during a stand-by period. As has been described with the examples in the first through the fifth embodiment, the printing apparatus of the present invention is provided with: an operation for preventing adhesion of the recording paper to a printing head or to a roller; and, prevention of a paper jam by thrusting out the recording paper stuck to the cutter unit; in addition to other effects as described in the individual exemplary embodiments. Furthermore, the present invention is able to realize a highly reliable printing apparatus of a small size, which alleviates a paper jam in a succeeding printing operation, and avoids an impairment to operation of a paper transfer mechanism and a cutter mechanism, even when a stand-by state continues for an extended time period, and under such severe environmental conditions as high temperature and high humidity, or low temperature and low humidity, etc. Accordingly, the printing apparatus is fit for not only household use, but also business use that requires a high reliability, and it is also suitable as a printing apparatus for outdoor use.

Claims: A printing device comprising: a printer head (27) for printing characters or figures on a recording paper (1c); a roller (26) pressing against said printer head (27) for transferring the recording paper (1c); a transfer mechanism for rotating said roller (26); a cutter unit (21, 22) provided downstream of said printer head (27); characterized in that said printing device being adapted for operating said transfer mechanism after a lapse of a predetermined amount of time during a stand-by period for transferring the recording paper (1 c) once in a first direction, then a) transferring the recording paper (1c) in a direction reverse to said first direction, and subsequently operating the cutter unit (21, 22), wherein said first direction is a forward direction; or b) operating the cutter unit (21, 22), and subsequently transferring the recording paper (1c) in a direction reverse to said first direction, wherein said first direction is a backward direction. A printing device according to claim 1, wherein said first direction is a forward direction, and wherein a leading end of said recording paper (1c) is located between a cutting edge and a backside (A) of said cutter unit (21, 22) after said transfer of the recording paper (1 c) in said direction reverse to said first direction. A printing device according claim 1, wherein said first direction is a forward direction, and wherein said recording paper (1 c) is again transferred in the forward direction after said operating of said cutter unit (21, 22). A printing device according to claim 3, wherein said recording paper (1 c) is located in its original position after said transfer in the forward direction which succeeds said operating of said cutter unit, said original position is an initial position of said recording paper (1c) at the start of said stand-by period. A printing device according to claim 3 or 4, wherein a leading end of said recording paper (1c) is located on a stationary blade (21) of said cutter unit (21, 22) after said transfer of the recording paper (1c) in said direction reverse to said first direction and during said operating of the cutter unit (21, 22). A printing device according to any of claims 1 to 5, further comprising a duct shaped paper discharge guide (29) for guiding a cut printed recording paper (1e); wherein the cutter unit (21, 22) automatically cuts the recording paper (1 c) and discharges the recording paper downward along said duct shaped paper discharge guide (29) after printing so as to form a cut printed recording paper (1e) for discharge and uncut unprinted recording paper (1c), and wherein the uncut and unprinted recording paper (1c) is further transferred in the forward direction in order to prevent said cut printed recording paper (1e) from being jammed in said duct shaped paper discharge guide (29). A method for operating a transfer mechanism and a cutter unit (21, 22) of a printing device, the printing device further comprising a printer head (27) for printing characters or figures on a recording paper (1c), and a roller (26) pressing against said printer head (27) for transferring the recording paper (1c), and said cutter unit (21, 22) located downstream of said printer head, characterized by after a lapse of a predetermined time during a stand-by period performing the following steps of: operating said transfer mechanism for transferring the recording paper (1c) once in a first direction, then a) transferring the recording paper (1 c) in a direction reverse to said first direction, and subsequently operating the cutter unit (21, 22), wherein said first direction is a forward direction; or b) operating the cutter unit (21, 22), and subsequently transferring the recording paper (1c) in a direction reverse to said first direction, wherein said first direction is a backward direction.

Inventors: ARAKAWA TOHRU, KOSHI KAZUMINE, MATSUI MASAAKI, SAITO NORIYUKI, SAKAI KEITA, SHIMIZU MASARU, TANAKA TOSHIO, ARAKAWA, TOHRU, KOSHI, KAZUMINE, MATSUI, MASAAKI, SAITO, NORIYUKI, SAKAI, KEITA, SHIMIZU, MASARU, TANAKA, TOSHIO
Applicants: MATSUSHITA ELECTRIC IND CO LTD, MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
Application year: 1998
Main classification: B65H19
IPC codes: B41J15