JPS58111964A - Sheet separating device - Google Patents

Abstract

PURPOSE:To reduce abrasion of the circumferential surface of a roll, to extend life of a fixing roll, and also to maintain the separating performance of a separating pawl satisfactorily extending over a long period of time, by constituting so that a position of the separating pawl contacting with the surface of the fixing roll can be moved in the lateral direction. CONSTITUTION:Plural separating pawls 6 for separating a sheet from a fixing roll 1 are supported by a supporting shaft 5 at suitable intervals so as to freely turnable. The separating pawl-supporting shaft 5 can be moved to a position shifted by a distance (l) in the axial direction by loosening a nut 22 by which a screw part 5b of the supporting shaft 5 has been fixed. After it has been moved, the loosened nut 22 is fixed. In the same way, a supporting lever 8 for supporting a spring which gives a rocking property to the separating pawl 6 moves by the distance (l), as well. In this way, since the contact position of the separating pawl 6 can be moved by the distance (l), abrasion of the contact place can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method for separating sheets that move in close contact with the surface of a rotating body that rotates in one direction, such as a fixing device, using a separation claw whose tip is in contact with the surface of the rotating body. Regarding a separation device.

Conventionally, as a method for separating a sheet that moves in close contact with the surface of a rotating body that rotates in one direction, such as a fixing roller of a copying machine, from the roller, a sheet separating device in which a separating claw is brought into contact with the roller surface is known. There is.

An example of this conventional sheet separating device will be explained based on FIGS. 1 and 2.

A fixing roller 1 is supported on a side plate F of a fixing device of a copying machine so as to be rotatable in the direction of the arrow. A pressure roller 2 is provided on the same side plate F, in contact with a part of the surface of the fixing roller 1, and rotates in the direction of the arrow. A drive gear 3 connected to a drive source (not shown) is connected to the shaft 1a of the fixing roller 1.
is provided, and the fixing roller 1 is configured to rotate in the direction of the arrow by the driving force from this driving source. In addition, a shaft for supporting the separation claw is supported on the side plate F.
A plurality of separation claws 6 are rotatably supported on the support shaft 5 at regular intervals. This separation claw 6 is
It is composed of a central trunk portion 6a, a claw portion 6b, and a rear free end portion 6C. A support rod 8 is supported on the side plate F in parallel with the shaft 5, and this support rod 8 and the rear free end 6 of each separation claw 6 are connected to each other.
A tension spring 9 is hung between the C and C. This tension spring 9 gives the separating claw 6 the habit of rotating clockwise in FIG. Due to this behavior, the claw portion 6b is brought into contact with the circumferential surface of the fixing roller 1.

A guide plate 10 is fixedly supported on the side plate F at a constant distance from the separating claw 6. A sheet passage P is formed by the guide plate 10 and the separation claw 6. This sheet path P is provided with a pair of rollers 12 and 13 that press against each other. The shaft 15a of one of the rollers 12 and 15 is provided with a drive gear 13b to which a drive force is transmitted from a drive source (not shown).

When this row 215 is rotated in the direction of the arrow by the drive source, the other rows 212 in contact with it are also rotated in the direction of the arrow.

In a fixing device equipped with such a sheet separation device,
When the sheet S on which the toner image is formed is fed between the fixing roller 1 and the pressure roller 2, the toner image on the sheet S is fixed. The sheet S that has passed between these rollers 1 and 2 is separated by the claw portion 6b of the separation claw 6 that is in contact with the surface of the fixing roller 1, and the sheet S is moved along the sheet path P to the guide plates 1 and 0. The paper travels along the same line, is gripped by rollers 12 and 13 located ahead, and is discharged to the outside. As described above, in the conventional sheet separating device, the separating claw 6 is given the habit of rotating clockwise by the tension spring 9, so that the claw portion 6b is always in contact with the circumferential surface of the fixing roller 1. ing. Therefore, abrasion of the contact portion H is accelerated, and the Teflon coating layer as an offset prevention layer that has become loose on the surface of the fixing roller 1 is peeled off. Furthermore, as wear of the contact portion H is accelerated, unevenness occurs on the surface of the fixing roller 1. As a result, the sheet separation performance deteriorates, and separation defects such as sheet wrapping around the fixing roller 1 are more likely to occur. Further, the conventional sheet separating device has a drawback that as the Teflon coat layer of the portion in contact with the claw portion 6b is peeled off, the anti-offset effect of the portion of the fixing roller 1 is weakened, causing an offset phenomenon.

The present invention was made in order to eliminate the above-mentioned drawbacks of conventional sheet separating devices, and its purpose is to make the position of the separating claw that contacts the surface of the moving body movable. This feature makes it possible to suppress wear on the peripheral surface of the movable body as much as possible, extend the life of the movable body, such as the fixing roller, and improve the separation performance of the separation claw for a long time. It is about maintaining it over time.

An embodiment of the present invention will be described below with reference to the drawings. Third
In the figures and FIG. 4, the same members as those of the conventional separation device are given the same reference numerals, and the explanation thereof will be omitted. As in the conventional separating device, a plurality of separating claws 6 are rotatably supported on a support shaft 5 at appropriate intervals. One end 5 of this support shaft 5
a is supported movably in the axial direction by one side plate F1,
A threaded portion is formed at the other end 5b of the support shaft 5, and a slot 5c for rotating the shaft is provided at the tip of the threaded portion 5b. This threaded portion 5b is supported by the side plate F2 by an axial fixing position adjustment mechanism for the separation claw. This position adjustment mechanism is formed by a bush 21 fixed to the side plate F'2 and a fixing nut 22 that fits into the threaded portion. Further, one end 8a of the spring support rod 8 provided parallel to the support shaft is bifurcated, and each of the bifurcated ends is supported by the side plate F1 so as to be movable in the axial direction of the support rod 8. has been done. A threaded portion is formed on the other end 8b of this support rod 8, and a slot 8c for rotationally moving this rod is provided at the tip of this threaded portion 8b. 8b is the support shaft 5
Similarly, it is supported by the side plate F2 by an axial fixed position adjustment mechanism. The position adjustment mechanism for the support rod 8 is formed by a bush 25 fixed to the side plate F2 and a fixing nut 24 that fits into the threaded portion.

In this manner, in the sheet separating device according to the present invention, after making a required amount of copies, first, the threaded portion 5b of the separating claw support shaft 5 is
Loosen the nut 22 that fixes it, insert the tip of a screwdriver or the like into the slot 5c of the threaded part 5b, and rotate the support shaft 5 along the screw. The contact portion H of the separating claw 6 can be moved to a position shifted by a distance l in FIG. 4 in the axial direction. After moving, the loosened nut 22 is fixed. Next, the support shaft 5 of this separation claw 6
Similarly, loosen the nand 24 that fixes the threaded part 8b of the support rod 8 that supports the spring that gives the separation claw 6 its swinging behavior, and insert a screwdriver or similar tool into the slot 5C of the threaded part 8b. By inserting the tip and rotating the support rod 8 along the screw, the support rod 8 can also be moved by a distance l in FIG. 4. After the movement, the loosened nut 24 is fixed.

In this way, the separation claw 6 can separate the sheets by a distance l. , and can be moved axially and separated at that position. Therefore, the contact position of the separation claw 6 can be moved by a distance l from the previous one, and instead of always contacting the same place to perform separation, the position can be changed, which reduces the wear and tear of the contact place. will no longer be promoted. As a result, a fixed position of the rotating body, for example, the fixing roller 1, is not peeled off, so that surface irregularities do not occur and the sheet separation performance does not deteriorate. In addition, according to this separation device, the separation claw does not always contact only a fixed location, so if the rotating body is a fixing roller, the Teflon coat layer applied to the surface may be peeled off by the separation claw. This prevents the offset prevention effect of the relevant portion from weakening.

Next, other embodiments of the present invention will be described with reference to the drawings.

Although the previous embodiment showed an example in which the support shaft 5 and the support rod 8 were moved separately in the axial direction, the present invention may have the following configuration.

In FIGS. 5 and 6, the other end 5b of the separation claw support shaft 5
is formed with an extension portion 5d that protrudes from one side plate F2. Further, the other end portion 8b of the support rod 8 also forms an extension portion 8d projecting from the side plate F2 similarly to the support shaft 5. The extension part 8d and the support shaft extension part 5d are provided with a connecting member 25, and the support member 25 is provided with fixtures 25a and 25b for fixing the extension part 8d and the support shaft extension part 5d, respectively. is provided, whereby the separation claw support shaft 5 and the support rod 8 are connected.

Further, the other end 5b of the separation claw support shaft 5 is provided with an appropriate number of circumferential grooves 5e. The gap N provided between each circumferential groove 5θ is
It is set equal to the moving distance l of the previous embodiment. A positioning lever 27 rotatably supported by a shaft 26 is provided on one side plate P2. The free end of this positioning lever is provided with a notch 27a that fits into the circumferential groove 5e provided at the other end 5b, and the upper end thereof is provided with a bent portion 27b.

The support shaft 5 of the separation claw B and the support rod 8 supporting the spring 9 that gives the separation claw 6 a swinging behavior are supported as described above. To move the support shaft 5 and the support rod 8 in the axial direction, the positioning lever 27 fitted in the circumferential groove 5e is held by the bent portion 27b and swung to move the positioning lever 27 into the circumferential groove 5θ. Remove from. Next, the connector 25 is moved in the axial direction until the other circumferential groove 5θ, which is separated by a distance N, is positioned outside the side plate F2, and the notch 27a of the positioning lever 27 is fitted into the circumferential groove 5e. Positioning lever 27
By swinging, the positions of the separating claw 6 and the spring 9 that gives it a swinging behavior can be simultaneously moved by a distance N in the axial direction. By configuring the sheet separating device in this way, the moving mechanism can be simplified.

Further, other embodiments of the present invention will be described with reference to the drawings.

7 and 8, the other end 5b of the support shaft 5 of the separating claw 6 is provided with a circumferential groove 5e spaced apart by a distance N, as in the above embodiment.

A support member 30 having a flange portion 31a fixed by a nut 31 and supporting the support shaft 5 is provided on the side plate F2. This support member 30 has a positioning nut 3
2 is provided, and this nut 32 is connected to a support shaft 5.2 inserted into the support 60. It engages with the circumferential groove 5e of the other end 5b.

Now, when moving the support shaft 5 in the axial direction, first loosen the positioning nut 32, move the support shaft 5 in the axial direction, and position it in another circumferential groove 5e provided at a distance N. This is done by engaging the nut 32.

In this way, the separation claw 6 can be moved and fixed easily. In this embodiment, positioning was performed using a positioning nut, but in the present invention, it may be performed using a well-known click-stop mechanism.

Although the above embodiment shows an example in which the separation claw 6 and the spring 9 that gives it a swinging behavior are supported separately on the side plates F, F2 by a support shaft and a support rod, the present invention In the case of a sheet separating device in which a winding spring is provided between the claw 6 and the support shaft 5, and a weight is provided in the separating claw 6, the separating claw 6 has a swinging behavior. It goes without saying that it is sufficient to only swing the support shaft 5 (separation claw 64).

Further, in the sheet separating device according to the present invention, a stopper is provided at the end of the support shaft 5 and the support rod 8 of the moving separating claw to regulate the amount of movement, so that the support shaft 5 and the support rod 8 are connected to the side plate R. , Fz may be prevented from shifting.

[Brief explanation of the drawing]

FIG. 1 is a side view of a conventional sheet separation device during fixing formation, FIG. 2 is a view of the device viewed from the sheet path direction, and FIG. 5 is a sheet separation device showing an embodiment of the present invention. FIG. 4 is a diagram showing the state of the above-mentioned device after it has been moved, and FIG. 5 is a diagram showing the state of support of the support shaft and support rod of a sheet separating device according to another embodiment of the present invention. Figure 6 showing
The figure is a perspective view of the support part of the support shaft of the above device, FIG. 7 is a view showing the support state of the support shaft of a sheet separating device showing another embodiment of the present invention, and FIG. 8 is a perspective view of the support shaft of the same support shaft. It is a perspective view of a support part. DESCRIPTION OF SYMBOLS 1... Fixing roller, 5... Support shaft, 5b... Threaded part. 6... Separation claw, 8... Support rod, 8b... Threaded part,
21...Bunyu, 22...Nut, 25...Button, 24...Nut, 5e...Peripheral groove, 27...
・Positioning lever, 3O...Support member, 52...
Positioning nut. Moυ Warm C Ryomo 7 Q City 6 Illusion 683-

Claims (1)

[Claims] In a sheet separating device of the type that separates a sheet moving in close contact with the surface of a rotating body rotating in one direction with a separating claw whose tip is in contact with the surface of the rotating body, the separating claw is supported and the rotating body 1. A sheet separating device comprising: a separating claw support means movable in the axial direction of a rotating body; and a fixing means for positioning and fixing the support means in the axial direction of a rotating body.