Abstract: In an electrophotographic imaging apparatus using a continuous form recording sheet, provided are a heat roller which is driven to rotate, and a back up roller driven by the heat roller to rotate, and a motor for driving the heat roller to rotate. In the imaging apparatus, the variation of the feeding speed of the recording sheet due to deformation thereof is detected, and the rotational speed of the motor is controlled so as to feed the recording sheet at a predetermined feeding speed.

Abstract: An electrophotographic printer using a plurality of types of continuous recording forms having different page lengths, respectively, with perforations being provided between pages of each of the continuous forms. The printer is operated at least in a standby state and in a printing state. The printer comprises feed means for feeding the continuous-form recording sheet loaded into the printer, and control means for controlling the feed means in such a fashion that the perforations is located at a predetermined position when the printer is in the standby state, regardless of the page length of the recording form loaded into the printer. The predetermined position coincides either with an image-transfer position or an image-fixing position.

Abstract: A data recovery device is employed in a printer using a continuous form recording medium for reprinting data after printing has been interrupted. In the data recovery device, the number of pages remaining in a predetermined area of the feed path of the recording medium is counted. A plurality of page buffers are sequentially read out and printed. The printing operation is controlled such that the one of the data storing means from which the data is read out and printed by the printing means is identified based on the number of the pages remaining in the predetermined area.

Abstract: A temperature control system is employed in a electrophotographic printer for controlling the temperature of a heat roller. In the system, the temperature of the heat roller is kept in a predetermined range of an operable range when printing is executed, and kept in a predetermined range of a standby range, which is lower than the operable range, when printing is unexecuted. The temperature of the heat roller is controlled to be raised up to the upper limit of the operable range before it is changed to be in the standby range when printing is terminated.

Abstract: A storage vessel detecting mechanism is used for detecting an error condition of a storage vessel, which is detachably fitted in a main apparatus. The vessel is movably fitted in the main apparatus, and one end of a movable member, which is pivoted, is engaged with the vessel. The other end of the movable member is located between first and second positions when the vessel is not installed and when the vessel is accommodating a predetermined amount of substances therein. It is determined whether the other end of the movable member is located in a predetermined range. An error condition of the vessel is detected when the other end of the movable member is located at a position other than in the predetermined range.

Abstract: In an electrophotographic printer, a toner image formed on a photoconductive member is transferred onto a recording medium by charging the recording medium and by making the charged recording medium contact the toner image formed on the photoconductive member. A transfer charger for charging the recording medium is arranged in such a fashion that the transfer charger faces the recording medium at the upstream-side portion, with respect to the feeding direction of the recording medium, of an area where the photoconductive member and the recording medium contact. Therefore, the recording medium is charged at the upstream side of the portion with respect to the lateral center of the portion where the recording medium and the image carrying means contact.

Abstract: A horizontal sync signal generating device for use with an optical printer to determine the starting positions of horizontal scannings on a photoconductive member for forming images thereon. The generation of horizontal sync timing signals is kept constant regardless of any difference in the characteristics of a light beam transmitted via each scanning face of a polygonal rotary member.

Abstract: An appartaus utilizing a continuous-form sheet having a plurality of perforations at predetermined intervals of length is provided with a plate member for upwardly guiding the sheet discharged from the apparatus. A connect member provided on the plate member, as well as the apparatus, are arranged to be brought into and out of engagement with each other. The continuous-form sheet discharged from the apparatus is bent at the perforations and falls beyond the plate to be neatly folded.

Abstract: A power controlling device capable of controlling the supply power to a drive system and to a control system for controlling the drive system. The power controlling device is provided with a main switch capable of turning on and turning off the power supplying device. When the power supplying device is turned off by the main switch, the drive system is turned off before the control system is turned off.

Abstract: A self-diagnosis device provided in a printer that detects more than one error among a plurality of functional mechanisms provided in the printer, with one process. Test devices are provided for testing the functional mechanisms, and a control unit operates the test devices to detect an error, even if errors have been detected in other functional mechanisms.

Abstract: A device for controlling a process of stopping a laser printer having a printing unit including a sensitive drum and a fixing unit. The stopping process control device is provided with a detecting unit for detecting errors occurring in the laser printer, a determining unit for determining whether or not an error detected by the detecting unit is very serious, and a control unit for controlling the printing unit and the fixing unit. The control unit stops the printing unit and the fixing unit after completing a printing and a fixing of the page being printed when the determining unit determines that the error is less serious, and conversely, immediately stops the printing unit and the fixing unit when the determining unit determines that the error is very serious.

Abstract: A printer for electrophotographically forming an image on a continuous-form recording paper. The printer has a transfer unit and a pair of heat fixing rollers which are brought into a withdrawn state, in a print stand-by state. Thus, the recording paper is out of contact with a photoconductive drum and a heat roll when the transfer unit and heat fixing rollers are in their withdrawn state. A pair of dust removing brushs are also brought into a withdrawn state in the print stand-by state so as to be out of contact with the recording paper.

Abstract: A horizontal sync signal generating device for use with an optical printer to determine the starting positions of horizontal scannings on a photoconductive member for forming images thereon. The generation of horizontal sync timing signals is kept constant regardless of any difference in the characteristics of a light beam transmitted via each scanning face of a polygonal rotary member.

Abstract: A device for feeding a continuous form in a printer, the device having a timer for controlling the width of a drive pulse for a main motor feeding the form. The timer is formed of a plurality of timers controlled by software. These plurality of timers being, for example, three timers measuring a constant time, and one timer measuring a variable time which is varied in accordance with a feeding speed of the form. The width of the drive pulse is determined by summing up a time obtained by multiplying the constant time by three and adding the variable time.

Abstract: A form feeding control device includes a sensor provided at an inlet mouth of a printer to sense whether or not a continuous form exists in the inlet mouth. A control unit feeds the continuous for transfer thereto of a printed image corresponding to one page of the continuous form. The printed image is then fixed on the continuous form. The control unit also feeds the continuous form to fix the printed image on one page when the sensor senses that the end of the continuous form has passed through the inlet mouth and that a printed image has been transferred to the continuous form.

Abstract: A justification system for use in a printer employing a continuous recording form. The justification system comprises a timing pulse signal generating system which generates timing pulses in synchronism with the traveling of sprocket holes of the continuous recording form. The timing pulses signals for commencing the printing on each printing segment defined on the continuous recording form and the timing for stopping the advancement of the continuous recording form are controlled based upon the above timing pulse signals. With this control, printing can be executed with a correct positional relationship with rules on each printing segment, even if the continuous recording form is set in the printer with a slight misalignment in the direction of the travel path of the continuous recording form or if the form itself has expanded or contracted in its longitudinal direction due to the effect of humidity.

Abstract: An image organizing unit for use in a laser beam printer. The image organizing unit comprises a character generator which has a plurality of character patterns, each of which has a larger number of pattern elements a long the width direction than that corresponding to a resolving power of the printer. A main-scanning clock pulse frequency is also set to be higher than that corresponding to the resolving power of the printer. With the thus constructed image organizing unit, the printing quality can be improved, particularly for oblique lines of characters, with the resolving power of the printer remaining unchanged.

Abstract: A justification system for use in an electrophotographic printer. The justification system comprises a detector which detects pulses occuring at intervals each covering a segment of a continuous form. A counter coupled to the detector counts the number of main scannings over the surface of a photoconductive drum during the time to feed each segment, as confirmed in the detector. The counted value is compared with a reference value by a differential arithmetic unit, the output of which is fed to a speed control to control the feed speed of the continuous form. This compensates for the fluctuations in printing positions of each segment due to systematic errors such, as expansion of the continuous form.

Abstract: In a printer, a guide mechanism guides opposite side edges of the recording medium to enable the recording medium to travel along a predetermined path. The guide mechanism is movable widthwise of the recording medium in accordance with a width of the recording medium. A position detector is interlocked with the guide mechanism for detecting a position of the guide mechanism widthwise of the recording medium to generate a position signal representative of the position of the guide mechanism. A controller is operative in response to the position signal from the position detector, for delaying timing, widthwise of the recording medium, at which the image information is recorded onto the recording medium, thereby regulating a printing start-up position on the recording medium.

Abstract: A justification system is provided for use in an electrophotographic printer. The justification system comprises a detector which detects the passage of individual segments of a continuous form which are being fed at a predetermined rate. A counter counts the number of main scannings of a laser beam carrying printing information over the surface of a photoconductive drum. A read control is connected to the detector and the counter and controls reading of main information stored by monitoring outputs from the detector and the counter so that printing of each segment always occurs at a predetermined position, synchronously with passage of the segments.