JPS5914454Y2 - automatic paper feeder - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an automatic paper feeding device used to automatically feed sheets of paper one after another into a computer printer or the like.

A pick roller that rotates in pressure contact with the top surface of the paper stacked on the hopper table is provided, and the friction between the pick roller and the paper feeds the stacked papers one by one in accordance with the rotation of the pick roller. Automatic paper feeding devices have been widely used in the past, which raise a hopper table in response to paper feeding and keep the paper feeding position constant using a microswitch or a proximity switch that detects the top surface of paper.

The paper sent out by the pick roller reaches the feed roller, which is made up of a drive roller and a driven roller that presses against it, where it is clamped and given a more accurately controlled feed. If the roller remains in pressure contact with the paper, a problem arises in that the accurate feeding of the paper is hindered by the friction load between the pick roller or the paper.

In order to avoid this, a method has been proposed that detects when the paper reaches the feed roller, moves the pick roller upward based on this detection signal, and releases the pressure contact of the pick roller.

However, this method has the disadvantage that a special drive mechanism must be provided to release the pressure contact of the pick roller.

In addition, when feeding paper without using an automatic paper feeder, the paper must be manually fed into the printer from the same paper feeding position as when automatic paper feeding is used, but the pick roller is installed at a fixed position. In the case where the paper is moved up or retracted upward, there is a drawback that the pick roller gets in the way during manual paper feeding.

This invention provides an automatic paper feeder that can release the pressure of the pick roller as needed without providing a special drive mechanism as described above, and that does not interfere with the pick roller during manual paper feeding. The purpose of this system is to provide a stopper that can move forward and backward to limit the descent of the pick roller, and to control the vertical movement of the hopper stand with the stopper advanced during automatic paper feeding, thereby preventing pressure contact of the pick roller. At the same time, when manually feeding paper, this stopper is retracted and the hopper table is lowered greatly.
The pick roller is retracted below the paper feeding position.

The following description will be made based on the embodiments shown in the drawings.

In the figure, 1 is a hopper table provided to be raised and lowered by a drive device (not shown), 2 is paper stacked on the hopper table 1, and 3 is a sheet of paper 2 that is pressed against the top surface of the paper 2 by its own weight or an appropriate spring force. 4 is a pick arm that pivotally supports the pick roller 3; 5 is a pick arm 4;
a pick arm shaft which is pivotally connected to a stationary member (not shown);
6 is a gate provided to send out sheets of paper one by one;
7 is a paper feed table, 8 is a driving roller 8a and a driven roller 8b
A sensor 9 is provided near the feed roller 8 and includes a light emitting device 9a and a light receiving element 9b.

10 is a stopper provided on the moving surface of the pick arm 4 to stop the descent of the pick roller 3 slightly below the paper feeding position; 11 is a spring for holding the stopper 10 on the moving surface; 12 is a spring for holding the stopper 10 on the moving surface; This is a lock shaft that is fixed to a stationary member (not shown) and pivotally supports the stopper 10.

Note that 13 in FIG. 4 is a manual paper feed table used for manual paper feeding.

The hopper stand 1 is positioned so that the top surface of the paper 2 is at a predetermined paper feeding position. A sheet of paper 2a is sent out toward the feed roller 8.

When the fed paper 2a reaches the feed roller 8 and the leading edge of the paper 2a is pinched, the sensor 9 detects the paper 2a and lowers the hopper table 1 by a predetermined amount.

The amount of descent of this hopper table is determined by pick arm 4 and stopper 1.
The pick roller 3 is set so that there is a slight gap between the uppermost surface of the paper 2 and the pick roller 3, which stops descending by contacting the pick roller 3 with zero or more contact.

In this state (FIG. 3), the pressure contact of the pick roller 3 is released, and the paper 2a is released from the pick roller 3 or the stacked paper 2a.
Accurately controlled feed is provided by the feed roller 8 without being hindered by frictional loads with the upper surface of the feed roller 8.

When the paper 2a is sent out from the feed roller 8 and detected by the sensor 9, the hopper stand 1 immediately returns to a predetermined position, completing preparations for feeding the next paper.

The stopper 10 is rotatably mounted around a lock shaft 12, and the stopper 10 can move forward and backward relative to the pick arm 4 as necessary.

This is to facilitate manual paper feeding at the same position as the automatic paper feeding position, and the stopper 1
0 in the clockwise direction in FIG.
Speaking of engagement with the pick arm 4, the hopper stand 1
As the pick roller 3 is lowered, the pick roller 3 can be lowered until the entire pick roller 3 is located below the paper feeding position.

In this state (Fig. 4), the manual paper feed tray 13 is placed at the paper feed position.
If you install the pick roller 3 during manual paper feeding,
It doesn't get in the way at all.

The tip of the stopper 10 is in contact with the side surface of the pick arm 4, and when the hopper stand 1 is raised from the state shown in FIG. The machine returns to the automatic paper feeding state.

As mentioned above, the automatic paper feeder according to this invention is provided with a stopper that limits the descent of the pick roller, and is configured to release the pressure of the pick roller only by controlling the vertical movement of the hopper stand. Therefore, it does not require a special drive means for releasing the pressure contact of the pick roller unlike conventionally proposed paper feeding devices, and has the feature that it has a simple structure and can be manufactured at low cost.

In addition, by making the stopper movable back and forth, the pick roller can be retracted below the paper feed table during manual paper feeding, so the pick roller does not get in the way during manual paper feeding, unlike conventional paper feeding devices. It is something that does not have any drawbacks.

[Brief explanation of the drawing]

The figures show one embodiment of this invention, in which Fig. 1 is a plan view, Fig. 2 is a side view showing the paper feeding state, and Fig. 3 is a side view showing the state in which the pressure contact of the pick roller is released. FIG. 4 is a side view showing the manual paper feeding state. 1: Hopper stand, 2: Paper, 3: Pick roller, 4: Pick arm, 5: Pick arm shaft, 8: Feed roller, 9:
Sensor, 10: Stopper, 11 Spring, 12: Lock shaft.

Claims (1)

[Scope of utility model registration request] A hopper stand, a drive device for raising and lowering the hopper stand, which is mounted so as to be able to move up and down, is biased downward by its own weight or a spring, rotates in pressure contact with the paper stacked on the hopper stand, and feeds out the paper by friction. An automatic apparatus comprising a pick roller and a detection means for detecting that the paper sent out by the pick roller reaches the feed roller, and releases the pressure contact between the pick roller and the paper in response to an output signal from the detection means. In the paper feeding device, a stopper that stops the descent of the pick roller slightly below the paper feeding position is provided so as to be able to move forward and backward, and during automatic paper feeding, with this stopper advanced, the hopper table is slightly moved by a signal from the detection means. Automatic paper feeding device that can separate the pick roller and paper by lowering it, and also allows the pick roller to be removed from the paper feeding position by retracting this stopper and lowering the hopper stand during manual paper feeding. .