JPS61200564A - Form separating device for fixing device - Google Patents

Abstract

PURPOSE:To prevent the separation layer of a heat roller from damaging by allowing the tip of a separation claw to move along the surface of the surface of a heat roller and moving a lower guide plate with pressure originating from a jam when the jam occurs in a form guiding member. CONSTITUTION:A rocking shaft 23 for supporting the separation claw 25 is formed in a crank shape. Therefore, when an excessive load is placed on the separation claw 25, the separation claw 25 moves along the separation layer 8 of the heat roller 5 and its tip 26 does not contact the heat roller 5 any more, so that the separation layer 8 is prevented from damaging. Further, a lower guide plate 30 is so set that a form is guided to a frame by a support shaft 36 and a support pin 37, but when large force is applied onto the lower guide plate 30 owing to the jamming of the form, the guide plate moves as shown by a chain line to relieving the force. Consequently, the form 40 staying while bent in a form guide part 10 does not press the separation claw upward and the separation layer of the heat roller is prevented from damaging.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a paper peeling device in a heating roller type fixing device such as a copying machine, and in particular, a paper peeling device in which a peeling claw is formed to be swingable in the circumferential direction of the heating roller. The present invention also relates to a device configured to automatically move the guide plate one step in the event of a paper jam between the fixing device and the feed roller, so that no extra pressure is applied to the peeling claw.

(Prior Art) Generally, in a copying machine using an electrophotographic process, in order to fix an unfixed toner image on copy paper, a heating roller using an internal heating element such as a halogen lamp and a heating A pressure roller is provided that contacts the roller with a predetermined pressure. Paper is inserted between the two rollers, and by applying heat and pressure, the toner is melted and the toner image is formed. I'm trying to make it stick.

As a conventional example in this field, Japanese Patent Application Laid-Open No. 57-507
There are those shown in Japanese Patent Publication No. 0, Japanese Patent Laid-Open No. 57-44169, and the like. In other words, in the device disclosed in Japanese Patent Application Laid-Open No. 57-5070, a guide plate for peeling paper from a heating roller is configured to be able to swing in synchronization with a toner peeling member. , Japanese Patent Publication No. 57-441
The device disclosed in Japanese Patent No. 69 includes a peeling claw provided in contact with a heating roller and a pressure roller, respectively.
A horizontally movable configuration is shown.

Further, to explain in more detail the structure of a conventionally commonly used fixing device, as shown in FIG. It is composed of a heating roller 5 in which a heating element 6 is housed inside a core 7, and the paper 40 is peeled off by a peeling claw 15 that comes into contact with a release layer 8 on the surface of the heating roller 5. .

In this type of heating row 55, an internal heating element 6 is housed inside a metal core 7 that is supported by a shaft (not shown) and has mechanical strength that can withstand pressure, and a heat-resistant surface is provided on the surface of the metal core 7. Materials that have good properties and release properties (toner offset prevention), such as HTV silicone rubber (formerly ghTemperature Vulcan)
5ilicone Rubber)
The mold release layer 8 is coated with polytetrafluoroethylene (P, TFE) or the like.

On the other hand, the pressure roller 2 described above is formed, for example, by an elastic body 4 provided on a shaft 3, and when it comes into contact with the heating roller 5, it presses with a predetermined pressure, and also has an elastic body 4. The body 3 is made of a material having elasticity and heat resistance, such as HTV silicone rubber, Sutsuso rubber, E
PDA rubber (Ethylene Propylene)
Diene Acryl Rubber)
It is made of heat-resistant elastic material such as

By the way, in such a fixing device, since the toner image on the paper 40 comes into direct contact with the surface of the heating roller 55, there is a situation where the paper 40 gets wrapped around the surface of the heating roller due to the adhesiveness of the melted toner. may occur. In order to prevent such situations from occurring,
A device is required to peel off the paper 40 wrapped around the surface of the heating roller 5.

Conventionally, as this type of paper peeling device, for example, 6th to 7th paper peeling devices
A peeling claw 15 made of metal or heat-resistant plastic is provided as shown in the figure, and the tip 16 of the peeling claw 15 is brought into contact with the surface of the heating roller 5. energize the two to make pressure contact with a predetermined pressure of several 2 to several +25.

According to this type of peeling device, the tip of the nail is prevented from rising from the surface of the heating roller 5 due to rotational vibration of the heating roller 55 or the paper 40 hitting the tip 16 of the peeling nail 15. As a result, the peeling claw 15 is set in a stable state.

However, in such a conventional paper peeling device, the sharp part of the claw tip 16 of the peeling claw 15 is in pressure contact with the surface of the heating roller 5, so that the sharp part formed on the surface of the heating roller 5 is not formed on the surface of the heating roller 5. An operation such as scraping the mold release layer 8 is performed. Therefore, in the case where the release layer 8 is formed of a soft elastic material such as HTV silicone rubber, the tendency of cutting the surface is noticeable, and furthermore, the tip 16 of the peeling claw 15 itself is also damaged. , the peeling claws will wear out and become rounded due to contact with the heating roller, impairing the durability and effectiveness of the peeling claws.

In addition, when fixing an unfixed toner image with a large amount of toner on the leading edge of the paper 40 or when a jam occurs within the paper guide member 10, the claw tip 16 should be strongly pushed toward the heating roller 5. A pressing effect may occur.

In such a state, the tip of the nail may dig into the release layer 8, which not only tears or scrapes the release layer 8, but also deforms the tip of the release nail. Therefore, there is an inconvenience in that it is necessary to replace these members each time.

Furthermore, in the conventionally used fixing device 1 as described above, the claw tip 16 of the peeling claw 15 comes into contact with the release [i8] of the surface of the heating roller 5, and the paper bonded to the heating roller 5 The peeling claw 15 used in the past has a structure as shown in FIG. 7.

That is, the angle between the nail upper surface 15a forming the nail tip 16 and the nail upper surface 15b is set to ψ -30 to 45 degrees, and the angle θ between the nail upper surface 15b and the tangent to the surface of the heating roller 5, that is, the peeling It is necessary to set the clearance angle of the claw 15 to be relatively large.

By setting in this way, the peeling claw 15
Although the tip 16 of the claw is made to stand up slightly with respect to the heating roller 5 to improve the paper peelability, as the relief angle θ is set larger, the paper peelability improves. On the contrary, the drawbacks of increased wear and damage to the release layer of the heating roller and the tips of the peeling claws are amplified.

In addition to the drawbacks of the conventionally used peeling claws as described above, the conventionally used paper guiding member 10 may also exhibit many drawbacks when a paper jam occurs. That is, the upper guide plate 11 and the lower guide plate 12 constituting the paper guide member 10 are each formed of a plate of metal or the like, and the two guide plates are spaced apart from each other at an interval of 0.5 to 2.0 mm as shown in the figure. Although the fixing device 1 side is wide and the feed roller 13 side is narrow and fixed, if the paper 40 after fixing jams in the paper guide member 10,
The jammed paper is bent many times and finally the peeling claw 15
It starts to push up. The pushed-up peeling claw may damage the release layer 8 of the heating roller 5 or damage the peeling claw 15 itself.

Also, when removing jammed paper, use a tool to remove the guide plate fixed to the frame of the copying machine, and then remove the paper that is tightly jammed inside.
It becomes necessary to fix the guide plate again, which complicates maintenance of the copying machine.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned drawbacks of conventionally used devices. , each has a new configuration to improve the peelability of the paper from the heating roller, and by configuring the guide plate to be swingable, it is possible to deal with jams between the paper guide members. It is an object.

(Means and Effects for Solving the Problems) The paper peeling device of the fixing device of the present invention is configured so that the tip of the peeling claw contacts the heating roller of the heating roller type fixing device, and the tip of the nail comes into contact with the heating roller of the heating roller type fixing device. If a jam occurs in the paper guide member, the paper can be moved by the pressure of the paper guide member, and the paper can escape without exerting the pressure on others. It consists of a guide plate.

The peeling device of the present invention has a peeling claw supported by a crankshaft-shaped support shaft and biased by a spring, and when a large load is applied to the tip of the claw, the tip of the claw touches the surface of the heating roller. It is made to move along the surface without being pressed too hard.

In addition, the lower guide plate of the guide plates constituting the paper guide member of the present invention has its leading end supported by the support shaft, and its other end engaged with the bin by the locking part, so that it can be easily attached. and is configured to be removable.

Therefore, in the paper peeling device of the fixing device of the present invention, when a load exceeding a set value is applied when peeling the paper from the heating roller, the peeling claw does not strongly press the surface of the heating roller. move along its surface,
Furthermore, even if a jam occurs within the paper guide member,
Since the lower guide plate moves in a direction to reduce the pressure, it is possible to reliably prevent the jammed paper from applying extra pressure to the peeling claw.

(Example) The structure of the paper peeling device of the fixing device of the present invention will be described according to the illustrated example. As shown in FIG.
The device of the present invention has a fixing bag @1 formed by combining a pressure roller 2 and a heating roller 5, and a nail tip 26 is brought into contact with the discharge side surface of the heating roller 5 after fixing. A peeling device 20 configured to peel paper. The paper guide member 101 is formed of the upper guide plate 11 and the lower guide plate 30, and includes a feed row 513 and the like.

The peeling device 20 of the present invention has a structure as shown in FIGS. 2 to 4, and has an end portion 23a supported by a shaft hole 22 of a support member 21 provided in a frame of a copying machine. The shaft 23 is formed in the shape of a crankshaft, and its center portion is configured as a pawl support shaft 24 to support the peeling pawl 25 .

In the support shaft 23 of the present invention, as shown in FIG. 2, a line connecting both ends 23a thereof and a line in the axial direction of the claw support shaft 24 are formed in parallel. A spring 27 provided on the pawl support shaft 24 presses the pawl tip 26 of the peeling pawl 25 toward the surface of the heating roller 5. Accordingly, it is also possible to provide a spring to restrict the range of its swing, as necessary.

The peeling claw 25 of the present invention is made of metal or plastic, similar to conventionally used peeling claws, and the tip 26 of the claw is formed at an angle of about 30 degrees.
Then, as shown in FIG. 3, the upper surface 25a of the nail,
The heating roller 5 is arranged so as to be in contact with the tangent line at an angle of 2 degrees.

Therefore, in the peeling claw 25 of the present invention, the relief angle is formed to be very small compared to the conventionally used peeling claw shown in FIG. Since the angle of intrusion between the two members when peeling is small, the pressing force exerted by the paper can be reduced.

Further, in the peeling claw of the present invention, as shown in FIG. 4, the swing shaft 23 for supporting the peeling claw 25 is formed in the shape of a crank. In the peeling claw of the present invention, when the claw is in contact with the heating row 55 in a normal state without being swung, the support shaft 23 supporting the peeling claw 25 moves as shown in (A). A pawl support shaft 24 is set at that position, and the peeling pawl normally performs the paper peeling action at that position.

However, in the present invention, as described above, the line connecting the shaft end portion 23a supported by the support member 21 and the claw support shaft 2
4 is far apart from the central axis of the support shaft 23, when a force is applied to the peeling claw 25 in the direction of the arrow F due to a paper jam or the like, the support shaft 23 will be swung in the direction of the force indicated by the arrow Fa. The trajectory becomes as shown by B. This trajectory is
Points (A) and (C) are respectively shown for the trajectory A when the peeling claw 25 is oscillated while maintaining a predetermined angle of 2° with respect to the surface of the heating roller 55. This will intersect at the intersection and draw a trajectory that passes inside it.

Since the peeling claw is swung according to the trajectory, the claw support shaft 24 passes through a position approaching the heating roller 55 as shown in (B), and the shaft 23 and the heating roller 5 are connected to each other. Since the length d of the line connecting the centers becomes a straight line, it is the shortest, and if it oscillates beyond that, the length of the line will gradually become longer.

In this case, the peeling claw 25 moves from the position shown by the solid line in FIG. 3 to the position shown by the chain line, and at the same time, the relief angle of the peeling claw gradually decreases to the position shown in FIG. 4 (b). When the support shaft moves to , the angle is set to about -3°. That is, when the clearance angle of the claw tip 26 of the peeling claw 25 with respect to the surface of the heating roller 5 becomes 0° or less, the tip does not come into contact with the top surface 25a of the claw, but the top surface 25a of the claw comes into contact with the surface of the heating roller 5.

Therefore, in the peeling claw of the present invention, when an extra load is applied to the peeling claw, the tip of the claw 26 is attached to the heating roller 5.
This prevents the mold release layer 8 formed on the surface of the heating roller 5 from being damaged.

Furthermore, if the load applied to the peeling claw 25 is large, the swing shaft 23 will move significantly, as shown in (c), and the relief angle of the claw tip 26 will gradually increase. However, since the peeling claw does not require any further swinging, a stopper 21a is usually provided to limit the swinging of the shaft, as shown in FIG. Either a stopper is provided at the top, or the weight of the peeling claw is used at the top to prevent unnecessary movement.

As described above, in order to obtain the effect of the peeling claw of the present invention, the shaft end 23a of the swing shaft 23 and the claw support shaft 2 must be
4 to a predetermined value, and the claw support shaft 2
It is necessary to set the swing locus B of No. 4 so that it passes inside the theoretical locus A within the range in which the claw operates.

In addition, in the embodiment of the present invention as described above, only one peeling claw is shown, but in reality, a good l! Either multiple peeling claws are formed in the middle of the driving wheel and each peeling claw is made to swing at the same time, or each peeling claw is formed so that it can swing on its own support shaft, and the setting is made for each peeling claw. It is also possible to oscillate each part separately when a load exceeding the specified value is applied. It is necessary to configure the settings as described above.

Furthermore, if the support shaft of the peeling claw of the present invention is swung for some reason, the swiveling motion is detected by a sensor (not shown) and displayed on the control panel of the copying machine. A member is used to notify the operator, and at the same time, the copying operation of the copying machine is stopped to prevent the abnormal situation from spreading further.

In addition to the above-described peeling device, in the paper peeling device of the fixing device of the present invention, a lower guide plate 30 constituting the paper guide member 10 is installed as shown in FIGS. 1 and 5(a) and (b). It is set up as follows.

The lower guide plate 30 of the present invention is made of a plastic or metal plate, and has its tip 31 supported by a support shaft 36 so that it can swing around the support shaft 36. , the other end is supported by a support pin 37 via a locking part 32, and when a force of more than a predetermined value is applied to the locking part 32, it will come off from the support pin.

As shown in FIG. 1, normally the lower guide plate 3
Both ends of the support shaft 36 are connected to the frame 35 of the copying machine.
The paper is set so as to be guided by the support bin 37, but if the paper jams, etc., the lower guide plate 30
When a large force is applied to the paper guide member 10, the paper 40 moves in the direction shown by the chain line to release the force. Situations such as pressing upward will no longer occur.

In addition, the lower guide plate 30 of the present invention is made slightly larger than the maximum paper width that can be copied in a copying machine, and, for example, the end of the paper comes into contact with the locking portions 32 on both sides of the lower guide plate 30. It seems like it never happens.

Further, the locking portions 32 formed on both sides of the lower guide plate 30 of the present invention can easily set the force for clamping the support bottle 37 to a predetermined value. When the pressing force of 25 is set as 1002', when a slightly larger force, that is, a force of 100 to 20025, is applied to the lower guide plate 30, the locking portion 32 engages the support pin. 37.

If the lower guide plate 30 comes off, the state is detected by a sensor (not shown), and the copying operation of the copying machine is stopped, and the operator is notified and the operator is instructed to take measures to recover from the jam. become.

In the embodiment of the lower guide plate 30 of the present invention described above,
Connect the end of the lower guide plate on the feed-out row 513 side to the fixed shaft 3.
Although the lower guide plate 30 of the present invention is shown supported at 6, it is also possible to set the lower guide plate 30 of the present invention by reversing the position of the supporting member. In any case, in the lower guide plate 30 of the present invention, when a paper jam occurs in the paper guide member 10, it is only necessary to automatically release the pressure, and the work of removing the paper can be performed. It will be necessary to make it easy to set it later.

(Effects of the Invention) Since the paper peeling device of the fixing device of the present invention has the above-described configuration, a situation occurs in which the paper is firmly adhered to the heating roller, causing the peeling claw to swing. However, the swinging of the peeling claw does not damage the surface of the heating roller, making it possible to protect the release layer formed on the surface of the heating roller.

Furthermore, since the tip of the peeling claw is swung so as to escape from the heating roller, damage to the peeling claw itself can be reliably prevented even if a large load is applied.

In addition, even if paper jams in the paper guide member, the pressure can be released by moving the lower guide plate. This prevents pressure from being transmitted to the peeling claws and other members and causing damage to these members due to excessive movement, thereby facilitating maintenance.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the configuration of the device of the present invention, FIG. 2 is a perspective view showing the configuration of the peeling device of the present invention, FIG. 3 is a side view thereof, and FIG. 4 is a side view showing the configuration of the peeling device of the present invention. FIG. 5 is an explanatory diagram showing the swinging motion of the peeling claw, and FIG. 5 is a diagram showing the configuration of the lower guide plate of the present invention, in which (a) is a plan view, (b) is a side view thereof, and FIG. FIG. 7 is a side view showing the configuration of a conventionally used fixing device, and FIG. 7 is an explanatory diagram illustrating the operation of a conventional peeling claw. Reference numeral 1 in the figure: fixing device, 2: pressure roller,
3...Shaft, 4...Elastic body, 5.
... Heating roller, 6 ... Internal heating element,
7...Core, 8...Release layer, 10-...
...Paper guide member, 11...Top guide plate, 12
...Lower guide plate, 13...Feeding roller, 15...Peeling claw, 16...Tail tip, 17...Shaft, 18 ... Spring, 20 ... Peeling device, 21 ... Support member, 22 ... Shaft hole, 23 ... Swing shaft,
24...Claw support shaft, 25...Peeling claw,
26...Claw tip, 27...Spring, 30...Lower guide plate, 31...Tip, 32...Locking part , 35... Frame, 36... Support shaft, 37... Support pin, 40... Paper, 41... Toner image. Figure 1 Figure 2 Figure 3 Figure 4

Claims (4)

[Claims] (1) A heating roller type fixing system consisting of a heating roller with an internal heating element formed inside it, and a pressure roller that is formed parallel to the heating roller and contacts the heating roller with a predetermined pressure. In the apparatus, a peeling claw for peeling off the paper attached to the surface of the heating roller is formed to be swingable in the circumferential direction of the heating roller, and a paper guide member for guiding the peeled paper to the delivery roller. is formed to be swingable, and when a load of more than a predetermined value is applied to the peeling claw or the paper guide member, these members swing in a direction to reduce the load. Paper peeling device of fixing device. (2) Using a guide plate as a paper guide member,
A paper peeling device for a fixing device according to claim 1, characterized in that the guide plate is supported by a shaft at one end, and the other end is attached to the shaft so as to be detachable from the shaft. . (3) The peeling claw is supported via a shaft member, and when a load exceeding a predetermined value is applied to the peeling claw, the tip of the peeling claw moves in the direction of escape. A paper peeling device for a heating roller type fixing device according to claim 1. (4) The shaft member supporting the peeling claw has a crank shape, and the shaft supported by the frame and the shaft supporting the peeling claw are formed parallel to each other, and between the shaft member, the peeling claw, and the frame. 4. A paper peeling device for a fixing device according to claim 3, further comprising a spring so as to bias the tip of the peeling claw toward the surface of the heating roller.