JPH0132049Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a remaining toner amount detection device that detects when the amount of toner remaining in a toner hopper of a copying machine is low.

As this type of remaining toner amount detection device, one shown in FIG. 1 is known. In FIG. 1, a toner hopper 1 stores toner 2 therein, and supplies the toner with a toner supply roller 3 provided at the bottom. A scraping plate 4 serves to scrape off excess toner adhering to the toner supply roller 3. Both ends of a rotating shaft 5 are supported on both side plates of the toner hopper 1, one end of a flexible rotating member 6 is fixed to the rotating shaft 5, and a magnet 7 is attached to the other end of the flexible rotating member 6. Further, a magnetic detection switch 8 such as a reed switch or a Hall element is provided on the side wall of the hopper 1 below the rotationally passing position of the magnet 7.

To explain the operation of this device, when the toner hopper 1 is sufficiently filled with toner, the flexible rotating member 6 rotates in a bent state due to the resistance of the toner 2, and the magnet 7 moves over the magnetic detection switch 8. When passing, the distance between the magnet 7 and the magnetic detection switch 8 is sufficiently far, so the magnetic detection switch 8
If the toner 2 in the toner hopper 1 is not turned on and the toner 2 in the toner hopper 1 is consumed and there is little remaining, the resistance of the toner 2 disappears, so the flexible rotating member 6 becomes almost completely stretched, and the magnet 7 passes over the magnetic detection switch 8. At that time, the switch was turned on because it passed very close.

By the way, in such a configuration, the flexible rotating member 6
It is difficult to select suitable materials. This is because the resistance of toner is extremely small, so in order for it to bend, the elastic constant must be very small, and the magnet will bend without toner due to its own weight. In addition, when the rotating shaft 5 rotates and the flexible rotating member 6 rotates from the position A in FIG. 1, the weight of the magnet 7 and the elastic repulsive force of the flexible rotating member 6 overlap, and There is a risk that the toner 2 below will fall and be thrown away, making it impossible to use the resistance of the toner 2 stably.

An object of the present invention is to solve the problems of the conventional toner remaining amount detection device and to provide a toner remaining amount detection device that has a simple structure and can reliably detect a shortage of toner remaining amount.

To achieve this purpose, the toner remaining amount detection device of the present invention includes a rotating shaft, a rigid support member fixed to the rotating shaft, and one end of which is rotated by the supporting member at a spaced apart position parallel to the rotating shaft. A rotating member having rigidity and freely supported; a magnet attached to the other end of the rotating member; and a magnetic sensor disposed below the rotating passing position of the magnet so as to detect the position of the magnet. is provided in a toner hopper that accommodates toner, and as the rotating shaft rotates, the distance between the magnet and the magnetic sensor when the magnet passes over the magnetic sensor changes according to the remaining amount of toner. This is a characteristic feature.

The remaining toner amount detection device of the present invention will be described in detail below with reference to the drawings.

FIGS. 2a and 2b are diagrams showing an embodiment of the present invention. For the sake of clarity, parts corresponding to those in the apparatus of FIG. 1 are given the same reference numerals. In FIG. 2, a toner hopper 1 stores toner 2 therein, and the toner is supplied by a toner supply roller 3 provided at the bottom.
A scraping plate 4 serves to scrape off excess toner adhering to the toner supply roller 3. Both ends of a rotating shaft 5 are supported on both side plates of the toner hopper 1. A rigid support member 10 is fixed to the rotation shaft 5, and one end of a rigid rotation member 11 is rotatably supported by a shaft 12 at a position parallel to the rotation shaft 5 and spaced apart from the support member 10. A magnet 7 is attached to the other end of the rotating member 11, and a magnetic detection switch 8 such as a reed switch or a Hall element is provided on the side wall of the hopper 1 below the rotationally passing position of the magnet 7.

FIG. 3 is a detailed view of the magnet support within the toner hopper 1. The partially bent portion 10a of the support member 10 prevents the rotation member 11 and the support member 10 from coming into close contact when the rotation member 11 is bent and covered over the support member 10 as the rotating shaft 5 rotates. It plays a supporting role by maintaining a predetermined angle. Since the rotating member 11 is displaced by the resistance of the toner, it is better to have a light weight.For example, the material may be a light metal or a synthetic resin sheet with a thickness of about 0.05 to 0.2 mm.

Next, the operation of this device will be explained. The rotation shaft 5 is driven in the direction of the arrows in FIGS. 2a and 2b by a drive device (not shown). Accordingly, the support member 10,
The rotating member 11 rotates within the toner hopper 1, and the rotating member 11 tends to hang down in the vertical direction due to the weight of the magnet 7. Therefore, as shown in FIG. 2b, when the toner 2 in the toner hopper 1 is empty, when the magnet 7 passes over the magnetic detection switch 8, the rotating member 1
2 is vertical, the magnet is close to the magnetic detection switch 8, and the magnetic detection switch 8 is in the ON state. On the other hand, when the toner hopper 1 is sufficiently filled with toner 2 as shown in FIG. 7 passes over the magnetic detection switch 8, the rotating member 1
1 has a certain angle with respect to the vertical direction. Therefore, the distance between the magnet 7 and the magnetic detection switch 8 is greater than when the toner 2 is empty, and the magnetic detection switch 8 remains in the OFF state. That is, the presence or absence of the toner 2 can be detected by utilizing the resistance of the toner 2 by rotating the rotating shaft 5.

The position where the magnet 7 turns on the magnetic detection switch 8 when the toner hopper 1 is empty when the toner hopper 1 is empty is set as a reference position on the rotating shaft 5, and it is set such that it always returns to this reference position and waits at the end of the copying operation. When the drive is controlled, magnetic detection switch 8 turns ON,
The OFF signal may be displayed as is on the display panel, and in this case, the electric circuit will be simplified and the device will be even simpler.

As described in detail above, in the toner remaining amount detection device of the present invention, the rotating member to which the magnet is attached is a rigid member, and the rotating member is mounted on a rigid support member fixed to the rotating shaft at a position parallel to and spaced apart from the rotating shaft. Since it is configured to be movably supported, the structure is simple and inexpensive, and the amount of toner remaining in the toner hopper can be easily and accurately detected.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of an example of a conventional toner remaining amount detection device, FIGS. 2a and 2b are sectional views showing the structure of an embodiment of the toner remaining amount detection device of the present invention, and FIG. FIG. 2 is a perspective view of the main parts of the device shown in FIGS. 2a and 2b; DESCRIPTION OF SYMBOLS 1... Toner hopper, 2... Toner, 3... Toner supply roller, 4... Scraping plate, 5... Rotating shaft, 6
...Flexible rotating member, 7... Magnet, 8... Magnetic detection switch, 10... Supporting member, 10a... Portion, 11... Rotating member, 12... Shaft.

Claims (1)

[Scope of utility model registration request] a rotating shaft, a rigid supporting member fixed to the rotating shaft, a rigid rotating member having one end rotatably supported on the supporting member at a spaced apart position parallel to the rotating shaft; A toner hopper containing toner is provided with a magnet attached to the other end of the member and a magnetic sensor disposed below the rotational passing position of the magnet so as to detect the position of the magnet. A toner remaining amount detection device characterized in that the distance between the magnet and the magnetic sensor when the magnet passes over the magnetic sensor changes depending on the remaining amount of toner.