JPH0419552Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a mechanism for detecting a non-operating position, that is, an open state, of a paper ejection mechanism section in an electrophotographic recording apparatus.

[Conventional technology]

In the paper ejection mechanism section of the electrophotographic recording device,
If paper gets stuck in front of this paper ejection mechanism,
It is necessary to provide a mechanism that allows the paper ejection mechanism to be opened in order to remove the paper or for maintenance and inspection. On the other hand, when such a mechanism is adopted, a mechanism is required to detect in advance that the paper ejection mechanism is in the open state so that the printing operation does not start when the paper ejection mechanism is in the open state. .

An open state detection mechanism for a paper ejection mechanism in a conventional electrophotographic recording apparatus will be described with reference to FIGS. 2 and 3.

In FIG. 2, reference numeral 1 denotes a paper ejection mechanism section, which is supported by the main body 2 via a shaft 3 so as to be openable and closable. Reference numeral 4 denotes a sheet guide, which is attached to the paper ejection mechanism section 1 with a detection hole 4a formed therein. Reference numerals 5 and 6 denote transmission type photo sensors, which are disposed on the sheet guide 4 so as to detect the conveyance of the paper within the paper ejection mechanism 1, and form an optical axis passing through the detection hole 4a of the sheet guide 4. Reference numeral 7 denotes a shutter, which is biased counterclockwise by a spring 8 so as to be rotatable by the paper ejection mechanism 1 so as to block the optical axis between the photo sensors 5 and 6 when the paper ejection mechanism 1 is in an open state. Install. A post 9 holds the shutter 7 so that the shutter 7 does not block the optical axis of the photo sensors 5 and 6 when the paper ejection mechanism 1 is in a closed state, that is, in an operating position. A latch lever 10 is rotatably attached to the side frame 11 via a rotating shaft 12 so as to hold the paper ejection mechanism 1 in a closed state, and is urged in the locking direction by a spring 13. Reference numeral 14 denotes a post, which is attached to the main body 2 so as to be engaged with the latch lever 10 when the paper ejection mechanism section 1 is in the closed state.
Attach to. 15 is the stopper and latch lever 1
Limit rotation of 0. 16 is a roller.

Next, the operation of the above structure will be explained. First, when the paper ejection mechanism 1 is in the closed state as shown in FIG. If so, the sensor output level of the photo sensors 5 and 6 will decrease. At this time, the sensor output level is monitored by a control unit (not shown), and if the sensor output level does not increase even after the conveyance time corresponding to the length of the paper has elapsed,
It is determined that there is a paper jam.

Furthermore, if the latch lever 10 is removed from the post 14 under normal conditions and the paper ejection mechanism 1 is opened at a predetermined angle around the shaft 3 as shown in FIG. As shown in FIG. 2, it rotates counterclockwise, thereby blocking the optical axes of the photo sensors 5 and 6. If this state continues for a certain period of time, the control section detects that the paper ejection mechanism section 1 is in the open state. Detect.

[Problem that the invention attempts to solve]

However, in such a conventional example, the number of parts increases and the structure becomes complicated, which not only increases the number of assembly steps and costs, but also causes problems in reliability.

The present invention was made to solve the above problem, and its purpose is to detect the open state of the paper ejection mechanism by shifting the optical axis between the photo sensors when the paper ejection mechanism is opened. The objective is to provide a simple mechanism at a low price.

[Means for solving problems]

In order to achieve this purpose, the present invention has a paper ejection mechanism attached to the main body of the apparatus so as to be openable and closable, and this paper ejection mechanism is fixed to a rotating shaft and latched to a post provided on the main body of the apparatus. a latch lever that holds the paper ejection mechanism in a closed state; a biasing means that urges the latch lever to rotate in a direction in which it locks onto the post; and a sheet guide that guides the ejection of paper from the main body of the apparatus. and a pair of photo sensors arranged opposite to each other across the sheet guide to detect the passage of paper through the sheet guide, wherein one of the pair of photo sensors is attached to the rotating shaft, and The other is fixed, and when the latch lever is locked to the post, the optical axes of both photo sensors are made to coincide with each other, and when the latch lever is detached from the post, the urging means is used to align the rotation axis and the latch lever. The present invention is characterized in that one of the photo sensors is rotated integrally to shift the optical axis, and further includes a determining means for determining whether the paper jam or the paper ejection mechanism is in an open state based on the output level of the photo sensor.

[Effect]

In the present invention having such a configuration, when the output level of the photo sensor is at a predetermined level, the determining means determines that the paper ejection mechanism section is in the closed state, and even if the output level decreases, it can be restored within a certain time. For example, it is determined that the paper is passing through the sheet guide, but when the output level of the photo sensor decreases for a certain period of time, it is determined that the jam of the paper passing through the sheet guide or the paper ejection mechanism is open.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1, 4, 5, and 6.

FIG. 1 is a side view of the main parts of an embodiment of the electrophotographic recording apparatus according to the present invention when the paper ejection mechanism section is in a closed state, FIG. 4 is a schematic rear view of FIG. 1, and FIG. FIG. 6 is a side view of a main part of an embodiment of the electrophotographic recording apparatus according to the invention when the paper ejection mechanism is in an open state, and FIG. 5 is a partial side view.

In FIG. 1, reference numeral 17 denotes a paper ejecting mechanism section, which is supported by the main body 18 via a shaft 19 so as to be openable and closable. 2
Reference numeral 0 denotes a latch lever, which is rotatably attached to the side frames 21 on both sides via rotating shafts 22 so as to hold the paper ejection mechanism 17 in a closed state. Reference numeral 23 denotes a spring as a biasing means, one end of which is connected to one of the latch levers 20 so as to bias the latch lever 20 in the locking direction, that is, in the counterclockwise direction.
0 and the other end engages with one side frame 21. Reference numeral 24 denotes a post, which is used by the latch lever 2 when the paper ejection mechanism section 17 is in the closed state.
Attach it to both sides of the main body 2 so that it locks with 0 respectively. 25 is a stopper, side frame 21
The rotation of the latch lever 20 is restricted by protruding from the latch lever 20.

Reference numeral 26 denotes a sheet guide, which is attached to the paper ejection mechanism section 17 with a protruding detection hole 26a. Reference numeral 27 denotes a transmission type first photo sensor, which can detect the conveyance of paper within the paper ejection mechanism section 17.
It is attached to the side frame 21 via a flange 28, and an optical axis passing through the detection hole 26a of the sheet guide 26 is formed. Reference numeral 29 denotes a second photo sensor of a transmission type, which is attached to the side frame 21 with a flange 30 opposite to the photo sensor 27 so as to detect the conveyance of paper within the paper ejection mechanism section 17;
An optical axis passing through the detection hole 26a of the sheet guide 26 is formed. Reference numeral 31 denotes a pair of rollers, one of which is rotated at a constant speed by a drive source (not shown) so that the paper can be conveyed.

Here, the sensor output level of the photo sensors 27 and 29 decreases while the paper passes through the paper ejection mechanism section 17, and changes in the sensor output level are monitored by a control section (not shown) as a determining means. ing. In the control section, the photo sensors 27 and 29 are activated even after the conveyance time corresponding to the length of the paper has elapsed.
If the sensor output level does not rise, it is determined that there is a paper jam.

Further, the stopper 25 is provided to protrude from the side frame 21 at an interval of, for example, several millimeters from the position of the latch lever 20 in the engaged state in the biasing direction thereof.
The purpose of protruding in this way is to prevent the stopper 25 from interfering with the engagement operation of the latch lever 20 that engages with the post 24, and to prevent the latch lever 20 from rotating by a predetermined angle. , the second rotating together with the latch lever 20.
This is to ensure that the second photo sensor 29 is deviated from the optical axis of the first photo sensor 27.

Next, to explain the effect of the above configuration, first
When the paper ejection mechanism 17 is in the closed state as shown in the figure, the biased latch lever 20 engages with the post 24 to hold the paper ejection mechanism 17 in the closed state, and the photo sensors 27 and 28 face each other. , when the paper passes between the sheet guides 26, the sensor output levels of the photo sensors 27 and 29 decrease. At this time, the sensor output level is monitored by a control unit (not shown), and if the sensor output level does not rise even after the conveyance time corresponding to the paper length has elapsed, it is determined that there is a paper jam. If the output level returns to the original level within the conveyance time, it is determined that the paper has passed.

Here, when the latch lever 20 is disengaged and the paper ejection mechanism section 17 is opened as shown in FIG. 5, the latch lever 20 is brought into contact with the stopper 25 by the spring 23. At this time, the rotation shaft 22 rotates with the rotation of the latch lever 20, and the second photo sensor 29 attached to the rotation shaft 22 rotates counterclockwise as shown in FIG. Therefore, the optical axis of the photo sensor 29 is shifted from the optical axis of the first photo sensor 27.

Generally, the effective distance of the optical axis of a transmission type photo sensor is about 2 to 4 mm, so even the slight deviation of the optical axis described above will cause the sensor output level of the photo sensors 27 and 29 to decrease, and if this state continues for a certain period of time, , the control unit determines that the state is equivalent to a paper jam in the paper ejection mechanism section 17, that is, the paper ejection mechanism section 17 is in the open state, and stops the recording operation until the paper ejection mechanism section 17 returns to the closed state. let

[Effect of idea]

As explained above, in the present invention, one of a pair of photo sensors for detecting the passage of paper through the sheet guide of the paper ejection mechanism is attached to the rotating shaft to which the latch lever is fixed, and the other is fixed.
When the latch lever is locked to the post of the main body of the device, the optical axes of both photo sensors are made to coincide with each other, and when the latch lever is disengaged from the post, the latch lever is biased by a biasing means that urges the rotation shaft and the latch lever. A determination that determines that a jam of paper passing through the sheet guide or a paper ejection mechanism section is in an open state when one of the photo sensors rotates as a unit so that the optical axis is shifted, and the output level of the photo sensor decreases for a certain period of time. Since the structure is equipped with means, the photo sensor for detecting the passage of paper, which is essential for the paper ejection mechanism, can also be used as a sensor for detecting the opening and closing of the paper ejection mechanism.Moreover, the shutter mechanism, which was conventionally required, can also be used. Since it is unnecessary, the number of parts can be significantly reduced.

Therefore, the structure is simplified, and an inexpensive and highly reliable electrophotographic recording apparatus can be realized.

[Brief explanation of the drawing]

FIG. 1 is a side view of the main parts of an electrophotographic recording device according to an embodiment of the present invention when the paper ejection mechanism section is in the closed state, and FIG. 3 is a side view of the main part of the conventional example when the paper ejection mechanism is in an open state, FIG. 4 is a schematic plan view of FIG. 1, and FIG. 5 is an electrophotographic record according to the present invention. FIG. 6 is a side view of a main part of an embodiment of the apparatus when the paper ejection mechanism section is in an open state, and FIG. 6 is a partial side view of FIG. 5. 17...Paper ejection mechanism section, 18...Main body, 20
... Latch lever, 22 ... Rotating shaft, 24 ... Post, 27 ... First photo sensor, 29 ... Second photo sensor.

Claims (1)

[Claims for Utility Model Registration] The device has a paper ejecting mechanism attached to the main body so as to be openable and closable, and the paper ejecting mechanism is fixed to a rotating shaft and is engaged with a post provided on the main body of the device to eject paper. A latch lever that holds the ejection mechanism in a closed state, an urging means that urges the latch lever to rotate in a direction in which it locks onto the post, a sheet guide that guides the ejection of paper from the main body of the apparatus, and An electrophotographic recording device comprising a pair of photo sensors arranged opposite to each other with a sheet guide in between to detect the passage of paper through the sheet guide, wherein one of the pair of photo sensors is attached to the rotating shaft and the other is fixed. When the latch lever is locked to the post, the optical axes of both photo sensors are made to coincide with each other, and when the latch lever is disengaged from the post, the biasing means rotates one of the photo sensors integrally with the rotating shaft and the latch lever. The photo sensor is rotated so that the optical axis is shifted, and the apparatus further includes a determining means for determining that a paper jam passing through the sheet guide or a paper ejection mechanism is in an open state when the output level of the photo sensor decreases for a certain period of time. An electrophotographic recording device characterized by: