JPS6210465B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a cylindrical scanning facsimile machine or a similar device such as a printer that has an automatic paper feeding and discharging function. The present invention relates to a paper winding device that clamps and releases both ends of paper of a fixed size to be wrapped using two bars.

Generally, in a facsimile machine, the width of the bar for holding down the paper should be as narrow as possible in order to increase the effective screen area relative to the circumference of the drum. In addition, although the height from the drum surface depends on the type of scanning element, it is generally necessary to reduce the height in many cases. Therefore, in many cases, the bar has a narrow thin plate structure. Since such a bar is generally supported only at both ends, the clamping force inevitably becomes weak near the center in the longitudinal direction, and this tendency becomes more pronounced as the drum becomes longer, and therefore the bar becomes longer. Furthermore, in drums that require higher speed rotation, centrifugal force causes the center of the bar to lift up, making it impossible to securely clamp the edges of the paper in either case. In order to increase the rigidity of the bar, there is a method of creating grooves on the drum side and making the bar thicker by the depth of the groove, but this may cause creases at the edges of the paper, and depending on the hardness of the paper, the area near the grooves may This is not a preferred method as it tends to cause floating.

Figure 1 shows the main part of a conventional paper winding device used in medium-speed facsimile machines with automatic paper feed and ejection for A4 size paper, and shows the form of paper clamping using a bar. be. 1 is a drum, 2 is paper, and 3 is a front bar for clamping the leading edge of the paper. Since the front bar 3 is formed to have a fish-shaped cross section, there is no need to consider weakening of the clamping force in the central portion. The rear end clamping bar 4 cannot have the same cross section as the front bar 3 due to the structure and operation of the automatic winding means. The rear bar 4 is formed to have a trough-shaped cross section, which is one of the narrow thin plate structures described above.
As will be described later, the present invention is basically intended to apply this structure to long drums and high-speed rotating drums, and for this purpose, it is necessary to apply a reliable clamping force to the member corresponding to the rear bar 4. Is required.

In the prior art, there is a method of fixing a permanent magnet on the drum side to attract the bar. This method can provide a strong and stable clamping force over the entire bar by selecting a magnet with appropriate magnetic force, so it can be said to be an effective method for clamping in the case of long drums or drums that rotate at high speed. The problem is the means of release. In the automatic paper feed/delivery system, the bar must automatically separate from the drum at a predetermined time to release the clamp on the edge of the paper. In a device that does not use magnets, the entire bar 4 is separated from the drum 3 by simply pushing up both ends of the bar 4 in the direction of the arrow as shown in Figure 2, but in a device that uses magnets, the bar 4 is moved away from the drum 3 as shown in Figure 3.
cannot be floated as a whole due to the attractive force of the magnet 5. Therefore, in this case it is necessary to apply a force to the entire bar to pull it away from the magnet. Therefore, as a conventional means, a method has been proposed in which, when necessary, a plurality of electromagnets with a stronger attraction force than the magnets on the drum side are applied to the back of the bar, energized, and then moved in a direction away from the drum. The mechanism and operation are complicated, and the equipment for this purpose is also large in size.

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper winding device that takes advantage of the stability of a clamp method using magnets and is configured to release a bar from a magnet using extremely simple means. An embodiment of the present invention will be described below based on the drawings. Here, Fig. 4 is a side view of the main parts of the device of this embodiment, Fig. 5 is a side sectional view with a part of the structure removed from Fig. 4 to clarify the bar opening/closing mechanism, and Fig. 6 is a side view of the drum. Fig. 6 is a side sectional view with a part of the structure removed from Fig. 4 to clearly show the structure of the drum, and Fig. 6 is a side sectional view with a part of the structure removed from Fig. 5 to clearly show the structure of the side surface of the drum. In both cases, the device is in a standby state before being supplied with paper.

The drum 1 is fixed to a drum shaft 6, and is stopped at a fixed position by a stop lever 8 engaged with a drum stop cam 7, which is also fixed to the drum shaft 6. The stop lever 8 is rotatably supported by a lever shaft 9, and is applied with a counterclockwise rotational force by a spring 10. A cam 12 fixed to the camshaft 11 displaces the stop lever 8 by its rotation when necessary. This displacement locks and releases the drum stop cam 7, and also turns the sensor 13 on and off. The ON and OFF signals of the sensor 13 turn ON and OFF an electromagnetic clutch (not shown) that connects the rotation input of the drum shaft 6 during paper winding via a control circuit (not shown).
Turn off.

Brackets 14 are symmetrically fixed to both longitudinal ends of the steel plate rear bar 4 shown in FIGS. 5 and 6. This bracket 14 is supported by a rotatable retainer 15 with respect to the drum shaft 6 so that it can move only in the vertical direction in the drawing. Bracket 1
A pin 16 and a pin 17 are fixed to the pin 4.
The rear lever arm 18 is rotatably supported by a pin 19 fixed to the retainer 15, and is supported by a spring 2.
0 applies a downward force to the bracket 14 via the pin 16. The bar opening/closing lever 21 rotatably supported on the lever shaft 9 is connected to the rear bar lever arm 1 by a pin 22 fixed to a part thereof.
8 is locked. The spring 23 applies a counterclockwise rotational force to the bar opening/closing lever 21. camshaft 1
A cam 24 fixed to the bar 1 controls the position of the bar opening/closing lever 21 by its rotation. A spring clutch mechanism (not shown) is provided at one end of the camshaft 11, and the camshaft 11,
Therefore, the cam 12 and the cam 24 are rotated to a predetermined angle.

In addition, a plurality of squeezing rollers 25 are connected to the bracket 2.
It is rotatably supported on a shaft 27 fixed to 6. Both ends of the bracket 26 are attached to a fulcrum shaft 28 (fourth
) and 29 (see FIG. 7a), respectively, are fixedly attached to a lever 30 and an arm 31 which are rotatably supported. As shown in FIG. 4, the lever 30 is given a counterclockwise rotational force by a torsion coil spring 32, but is maintained at a predetermined position by a stopper 33. A link 36 connecting a pin 34 fixed to the bar opening/closing lever 21 and a pin 35 fixed to the lever 30 transmits the displacement of the bar opening/closing lever 21 due to the rotation of the cam 24 to the lever 30, and at a predetermined time. It serves to separate the squeezing roller 25 from the drum 1.

The front bar 3 (FIG. 6), which has been dropped into a groove provided in the drum 1, is supported by front bar lever arms 37 that pass through holes drilled near both ends of the front bar 3 (FIG. 6). The front bar lever arm 37 is rotatably supported by pins 38 fixed to both sides of the drum 1, and applies a downward force to the front bar 3 by a spring 39. Holding position.

A plurality of magnets 5 are very small rare earth permanent magnet machines, and a plurality of magnets are fixed to the drum 1 along with the yoke 41 in the longitudinal direction thereof. The configuration of the main parts has been explained above, and the remaining part of the configuration will be described in the operation description below.

In FIG. 6, the paper 2 is moved to the feed path 4 by a paper feed roller (not shown, hereinafter the same) in response to a paper supply command.
2. When the leading edge of the paper 2 passes the paper edge detector 43, the detection signal causes the camshaft 1 to
1 starts rotating. The feeding speed of the paper 2 and the rotational speed of the camshaft 11 are set in a constant relationship, and when the leading edge of the paper 2 enters the opening 44 of the front bar 3, the cam 24 is rotating at an angle θ1. It's becoming like that. As the cam 24 rotates by θ1, the bar opening/closing lever 21 is displaced by the step difference of the cam 24. In addition,
A detector (not shown) detects this point, that is, the rotation end point of angle θ1, and this signal causes the paper feed roller to stop.

Figures 7 to 9 are diagrams for explaining the following operations, where a in each figure shows the changes from Figures 4 and 5 step by step, and b shows the changes from Figure 6 in the same way. .

In FIG. 7, as the bar opening/closing lever 21 is displaced, the rear bar lever arm 18 is displaced and the bracket 14 is lowered. is closed, so that the leading edge of the paper 2 is clamped. Then, the cam 12 rotates the stop lever 8 clockwise, so that the stop lever 8 releases the lock of the drum stop cam 7 and turns on the sensor 13. The cams 12 and 24 temporarily stop when point B reaches point A.

When the sensor 13 turns on, the electromagnetic clutch connects the rotation of the drum shaft, and the drum 1 starts rotating.
The paper 2 is wound around the outer periphery of the drum by a squeezing roller 25 while being brought into close contact with the outer periphery of the drum. Since the rear bar lever arm 18 is locked to the pin 22, the rear bar 4 is maintained at the position shown in FIG. 7 without the retainer 15 moving.

When the trailing edge of the paper 2 passes the paper edge detector 43,
The camshaft 11 starts rotating again in response to the detection signal. The drum 1 and the camshaft 11 rotate at synchronous speeds, and when the rear end of the paper 2 reaches below the rear bar 4, the cam 24 rotates by an angle θ2. By rotating the cam 24 by θ2, the bar opening/closing lever 2
1 is displaced to the state shown in FIG. 8 (the cam 24 stops again here), and after being released from the lock by the pin 22, the lever arm 18 pulls down the bracket 14. At the same time, the rear bar 4 clamps the rear end of the paper 2 by the attraction force of the magnet 5. Furthermore, link 36 at the same time
The squeezing roller 25 is separated from the drum surface. The detector 45 detects the movement of the lever 30 at this time and switches the rotation of the drum 1 from the winding speed to the main scanning speed. This completes the winding of the paper.

When a command to return to the initial state is issued, the drum 1 starts rotating at the winding speed. When the rear bar 4 passes through a position approximately 180 degrees different from that shown in the figure, a cam rotation command is issued by a detector (not shown) that detects this moment. When the camshaft 11 rotates by an angle θ3,
(Figure 9 below) The bar opening/closing lever 21 returns to its original position (Figure 5), the squeezing roller 25 also returns in the same way, and the stop lever 8 loses its locking with the cam 12 and slides into contact with the outer periphery of the drum stop cam 7. . The cams 12, 24 rotate further, return to the position shown in FIG. 4, and stop. By returning the bar opening/closing lever 21 to its original position, the rear bar lever arm 18 is rotated clockwise by the pin 22 with the pin 19 as a fulcrum as the drum 1 rotates.
is pushed up. This figure (Figure 9) shows the bracket 14 in the middle of being pushed up.
The vicinity of both ends of the rear bar 4 along with the bracket 14 are being separated from the drum 1. This corresponds to the situation shown in FIG.

When the drum 1 further rotates from the state shown in this figure (FIG. 9), the bracket 14 is further pushed up, and therefore the pin 17 pushes up the front bar 3 via the front bar lever arm 37. Then, the rear bar 4 is pushed up by the eave-like portion 3' on the left side of the front bar 3, and is separated from the attraction by the magnet 5. After this moment, the bar 4, together with the bracket 14 and the retainer 15, loses its rotational power with the drum 1, but at the next moment, the pin 40 fixed to the side of the drum 1 rotates with the bracket 1.
Press the side of 4 to continue rotating. A groove 14' is provided on the surface of the bracket 14 facing the side surface of the drum, and the rear lever arm 18 is connected to the pin 22.
When the bracket 1 reaches the position where it is locked by
4 is pushed up to the highest position so that the pin 40 can fit into this groove 14'. Therefore, the bracket 14 is now released from the side pressure force exerted by the pin 40 and stops together with the retainer 15. Since the drum 1 continues to rotate, the front bar 3 is subsequently pushed up to the highest position by the front bar lever arm 37 of the pin 17 and moves under the rear bar 4.
At this time, the drum stop cam 7 is moved to the stop lever 8.
It is in a position where it is locked by. Stop lever 8
With the locking operation, the sensor 13 is turned OFF and the drum rotation input is cut off.

The device is now in its initial state (Figures 4 to 6)
, and the clamps at the front and rear ends of the paper 2 are released. After this, the paper is ejected, but this is not the gist of the present invention and will therefore be omitted.

As is clear from the above embodiments, according to the present invention, the end of the paper can be automatically and reliably clamped on a long drum or a drum rotating at high speed, and the rear bar can be released from the magnet. By utilizing the movement of the front bar when the clamp is released as a means, the clamp can be released reliably at the correct time, and a paper winding device with an extremely simple mechanism can be provided.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are explanatory diagrams of a conventional paper winding device, FIG. 4 is a side view of a main part showing an embodiment of the present invention, and FIG. 5 is a partial view of FIG. 4. FIG. 6 is a side sectional view showing the structure removed from FIG. 5, FIG. 6 is a side sectional view showing the structure removed from FIG. 8a and 8b show the state when the front end of the sheet is clamped, FIGS. 8a and 9b show the state when the rear end is clamped, and FIGS. 9a and 9b show the state during the clamp release process, respectively. 1...Drum, 2...Paper, 3...Front bar, 4
... Rear bar, 5... Magnet, 11... Rear bar lever arm, 14... Bracket, 21... Bar opening/closing lever, 24... Cam, 37... Front bar lever arm.

Claims (1)

[Claims] 1. A rotating drum for wrapping the paper, a front bar with an eave shaped part in the opposite direction to the paper leading edge clamping part, and a rear bar on the drum near the eave part side for the suction action of the rear bar. A plurality of permanent magnets are fixed in the length direction of the drum, and a narrow thin plate member whose rear end in the width direction overlaps the eaves-like part of the front bar when clamped. a rear bar that clamps the rear end of the sheet of paper; and a control mechanism that opens and closes the front bar and the rear bar; The paper winding device is characterized in that the rear bar is pushed up at a portion to release the rear bar from the attraction force of the permanent magnet.