JPS60129601A - Remains detector of recording paper - Google Patents

Abstract

PURPOSE:To reduce poor operation with a simplified construction by converting the displacement of a contact piece with respect to the highest surface of a recording paper rolled or stacket into an electrical signal to display the remains of the paper. CONSTITUTION:A conductive contact piece 12 contacting the outer surface of a rolled recording paper 11 is made rotatable centered on a support shaft 14 supported on a bracket 13 to charged on the paper surface with a coil spring 15 and conductive roller 18 is brought into contact with the endface of a spool 17 in which a conductive contact 16 at the tip of the contact piece 12 is kept in contact with the internal one side thereof. Then, the contact piece 12, the contact 16, the spool 17 and the roller 18 are connected together in series to form an input section of a residue display electric circuit and a display (not illustrated) is provided at the output section thereof. The distance to the contact 16 from the roller 18 is varied with changes in the remains of the paper 11 thereby enabling the indication of changes in electric resistance for the duration.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a recording paper remaining amount detection device in a recording apparatus such as a facsimile or a copying machine.

Conventional configuration and problems The recording device is equipped with a recording paper remaining amount detection device in order to prevent recording from being interrupted due to running out of recording paper during recording, and to appropriately manage recording paper inventory. It is equipped. A conventional recording paper remaining amount detection device is comprised only of mechanical parts, as shown in FIG. 1, for example. This device is
Roll-shaped record 2 A contact piece 2 that contacts the outer circumferential surface of the paper 1 and a rotating habit of the contact piece 2 in a clockwise direction around a support shaft 4 via a connecting rod 3. A tension coil spring 5, a wire 9 connected at one end to the connecting rod 3, the other end connected to another tension coil spring 6 having weaker spring characteristics than the coil spring 6, and passed around a roller 7.8. , a pointer 10 fixed to a wire 9 between rollers 7 #8, and a scale plate 11. Since the contact piece 2 is constantly pressed against the outer circumferential surface of the recording paper 1 by the coil spring 6, when the recording paper 1 decreases, the displacement is transmitted to the wire 9 via the connecting rod 3, and the pointer 10 moves to adjust the scale. Instructions change. Therefore, by setting the scale of the scale plate 11 in advance in correspondence with the remaining amount of recording paper 1, it is possible to know the remaining amount of recording paper at that time.

However, in such a conventional device, since the remaining amount of recording paper is detected by a mechanical method, the structure is complicated and there is a high possibility that malfunctions will occur. In addition, if it is desired to display the remaining amount at a position away from the recording paper, the interval between them becomes large, making the configuration even more complex and difficult to adjust. To provide a recording paper remaining amount detection device which has a simple configuration, has few malfunctions, and can easily display the remaining amount at a position away from the recording paper.

Structure of the Invention The recording paper remaining amount detection device according to the present invention brings a contact piece into contact with the uppermost paper surface of a roll-shaped or stacked sheet-like recording paper, and displaces this contact piece to follow changes in the remaining amount of the recording paper. This displacement is converted into an electric signal and visually displayed to detect the remaining amount.

DESCRIPTION OF THE EMBODIMENTS In an embodiment of the present invention shown in FIG. 2, the displacement of the contact piece 12 that contacts the outer peripheral surface of the roll-shaped recording paper 11 is detected as a change in electrical resistance. That is, the conductive contact piece 12 is rotatable about a support shaft 14 supported by a placket 13, and is given the habit of constantly contacting the surface of the recording paper 1 by a tension coil spring 16. A conductive contact 16 provided at the tip of the contact piece 12 is in contact with one inner surface of a spool 17, which is an electrical resistor. A conductive roller 18 comes into contact with the end face of the spool 17, and the contact piece 12, the contact 16, the spool 17, and the roller 18 are connected in series to form an input section of a remaining amount display electric circuit. The output of this electrical circuit is equipped with a known analog or digital display.

Next, the operation of this device will be explained. When recording is performed and the remaining amount of the recording paper 11 decreases, the contact piece 12 biased by the spring 15 follows this and rotates around the support shaft 14, and the position of the contact 16 changes to the spool. Since it moves from the end face of the roller 17 toward its center, the distance from the roller 18 to the contact 16 changes, and the electrical resistance therebetween changes. This change in electrical resistance is displayed analogously and digitally on the display section, and the remaining amount of recording paper 11 is detected.

The 5-base spool 17 can be integrally molded as an electric resistor using conductive resin or the like, but only on one inner side thereof, for example, a spiral resistance wire, a thin film resistor formed by metal vapor deposition,
A thick film resistor made of a metal oxide film, a film made of a conductive resin, or the like may be provided.

Further, instead of the conductive roller 18, a conductive leaf spring may be brought into contact with the spool 17, and the handle 19 of the spool 17 may be brought into contact with the spool 17.
The change in resistance from the center of the spool 17 to the contactor 16 may be detected by using the terminal as a terminal. Furthermore, the change in electrical resistance due to the displacement of the contact 16 may be performed via an electrical resistor separate from the spool door. As long as it comes into contact with the outer circumferential surface of the recording paper 11 and is displaced in accordance with changes in its remaining amount, the method and shape are free, regardless of whether it is an oscillating motion or a linear motion. In another embodiment of the present invention shown in FIG. It is detected as a rotational angle displacement.

In still another embodiment of the present invention shown in FIG. The amount of light received by the shift sensor 23 is changed by the displacement of , and the amount of light received by the shift sensor 23 is converted into an electric signal by the photosensor 23.

In the present invention, as means for converting the displacement of the contact piece 12 into an electrical signal, the position, pressure, angle, etc. of a position sensor, proximity switch, differential transformer, resolver, etc. arranged at the twelfth end of the contact piece 12 are used. Various electrical sensors capable of detecting displacement of can also be used.

Effects of the Invention As is clear from the above description, the recording paper remaining amount detection device of the present invention detects the displacement of the contact piece that contacts the top surface of the recording paper due to changes in the remaining amount of recording paper using an electric signal. Since this is done by converting it into a 71° recording paper, the configuration of the device used is simple, there are few malfunctions, and the remaining amount can be easily displayed at a position away from the recording paper. Note that the present invention has similar effects in detecting the remaining amount of sheet-like recording paper stacked on a table.

[Brief explanation of drawings]

Figure 1 is a diagram showing the main parts of a conventional recording paper remaining amount detection device;
The figure is a perspective view of a main part of a recording paper remaining amount detection device according to the present invention.
FIGS. 3 and 4 are diagrams showing the main parts of other embodiments of the present invention, respectively. 11...Recording paper, 12...Contact piece, 1
3... Bracket, 14... Support shaft, 1
5... Spring, 16... Contact, 17.
... Spool, 18 ... Conductive roller.

Claims (1)

[Claims] □ A contact piece that contacts the top surface of the rolled or stacked recording paper, a conversion means that detects the displacement of this contact piece due to changes in the remaining amount of recording paper □ and converts it into an electrical signal, and a A recording paper remaining amount detection device having a display means for displaying the remaining amount of recording paper.