JPS5938774A - Thermal fixation device - Google Patents

Abstract

PURPOSE:To decrease the consumption of an offset-preventive liquid and to prevent the clogging of a supply member for the preventive liquid, by installing a supply member and a cleaning member, and engaging the same with a heat roll under prescribed control. CONSTITUTION:A heat roll pair 1 consists of a heat roll 3 and a pressurizing roll 4. Transfer paper S is thermally fixed by the roll 3. A supply means for an offset-preventive liquid is constituted of a silicone oil storage vessel 6, a liquid supply member 7, a support member 8, a spring 9 and a solenoid 10 and coats the offset preventive liquid of silicone oil on the roll 3. A cleaning member 17 is provided to an arm 21 having a pad 16 actuated by a solenoid 19 and a spring 18. When the transfer paper approaches the roll pair 1, the member 7 contacts with the roll 3 and coats the silicone oil thereon. The pad 16 is held detached from the roll. When the transfer paper goes out after finishing fixing, both are reversed.

Description

[Detailed description of the invention] The present invention relates to a heat fixing device such as a copying machine.

Conventionally, in a heat fixing device, an anti-offset liquid supplying means for supplying and applying an anti-offset a was constantly in contact with a heat fixing roller. When a copying machine or the like is in operation, the surface of this heating fixing roller is quite flat (approximately 180°0).
Therefore, the offset prevention liquid supplying means that contacts the heating fixing roller and rotates at
When the fixing action is not performed, K also supplies the anti-offset liquid to the heating fixing roller, and there is a problem that the anti-offset liquid is wasted. Since it also served as a cleaning means for the fixing roller, clogging caused by toner
It occurs relatively early, and uneven or incomplete coating of the preventive liquid and poor cleaning tend to occur.

A first object of the present invention is to provide a heat fixing device that suppresses wasteful consumption of anti-offset liquid.

A first object of the present invention is to provide a heating fixing roller pair;
a first position for supplying the anti-offset liquid to the roller; an offset prevention liquid supply means selectively positioned at a second position where no offset prevention liquid is supplied; and when the pair of heating and fixing rollers is passing paper, the offset prevention liquid supply means is positioned at the first position. position, and when the pair of heat-fixing rollers is not passing paper, a moving means for positioning the anti-offset liquid supply means in the second position. This is achieved by a heat fixing device characterized in that the anti-offset liquid is supplied to the rollers only when the paper passes through the rollers.

According to the present invention, by movably supporting the offset preventing liquid supply means, wasteful consumption of the offset preventing liquid is avoided.

A second object of the present invention is to provide a heat fixing device in which clogging of the offset prevention liquid supply means is prevented.

This object of the present invention is achieved by a heat fixing device r characterized in that a cleaning means is added to the heat fixing device described above.

According to the present invention, since the cleaning means is added in addition to the offset prevention liquid supply means, there is no need to provide the offset prevention liquid supply means with a cleaning function (this prevents clogging of the offset prevention liquid BL supply means). can be prevented.

That is, the offset prevention liquid can be supplied uniformly and stably, and the off-set prevention effect can be maintained over a long period of time.

In addition, the heating fixing device has a cleaning section 4N in the cleaning means, and an application section 4'A which directly applies offset prevention liquid to the roller in the offset prevention liquid supply means. is supported by one support part H, and the means for moving the cleaning means and the means for moving the anti-offset liquid supply means are constituted by one driving means. Control of prevention liquid supply means @
Even one method can be simplified.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 21.

In these figures, reference numeral 1 indicates a pair of heating constant rollers. This roller pair 1 consists of a heating roller 6 having a heat source 2 inside thereof, and a pressure roller 4 which rotates in pressure contact with this roller, and is rotated in the direction indicated by the arrow. The toner image formed on the sheet S is conveyed with its image portion toward the heating roller 3, and is heated and pressed by the pair of rollers 1 to fix the toner image.

An anti-offset liquid, such as silicone oil, is applied to the circumferential surface of the heating roller 3 by an anti-offset liquid supply means. The off-set prevention liquid supplying means includes a piece of offset prevention liquid that stores silicone oil, a felt 7 as an offset prevention liquid supplying member having one end 7a immersed in the piece, a support member 8 that supports this felt 7, and this member. 8
It consists of a spring 9 and a solenoid 10 for moving the .

The support member 8 is swingably disposed about a pivot shaft 12. An arm 13 provided integrally with the support member 8 constantly biases the member 8 clockwise. The spring 9 is connected to a solenoid 10 for swinging the member counterclockwise.

The solenoid 10 is turned off in response to a signal detected by a sheet sensor (not shown) located in front of the roller pair 1 when the sheet path is OK, and the roller A sheet sensor (not shown) disposed on the rear side of pair 1 is turned on by a signal that detects the rear end of the sheet that has passed through the nip portion of the pair of rollers.

That is, when the roller pair passes through the paper, the felt 7 is located at the first position where it is brought into pressure contact with the heating roller roller by the elasticity of the spring 90, and when the paper passes, the solenoid 1
0 places it in a second position spaced apart from the heating roller.

The above-mentioned sheet passing time includes not only the time during which the sheet S is held between the roller pair 1 but also the heating roller 3 that comes into contact with the sorting when the leading edge of the sheet S is gripped by the roller pair. This also includes the time required to pre-apply silicone oil to the surrounding surface of the

That is, when the sort s is held in the nip portion of the roller pair 1, the surface of the heating roller 3 must already be coated with silicone oil. In other words,
When the sheet S is held between the nip portion of the pair of rollers, silicone oil is present on the surface of the heating roller, and this surface is previously coated with silicone oil by the felt 7.

Then, at the first position, the felt Z&'' is used to draw up the liquid oil in the tank 6 and apply it to the surface of the rotating heating roller 6.

Further, a cleaning means is provided on the circumferential surface of the heating roller 6 to clean the circumferential surface, and this cleaning means is provided with a cleaning pad 1, for example, as a cleaning member for removing toner attached to the roller circumferential surface.
6, a support member 17 for supporting the cleaning hat 16, and a spring 18 and a solenoid 19 for moving this support member.

This support member 17 is arranged so as to be able to swing freely around a pivot 20. An arm 21 provided integrally with this support member 17 has an arm 21 that allows the support member 17 to move in the counterclockwise direction at all times. (
A spring 18 biased by -1 is connected to a solenoid 19 for swinging the member in the 31 direction.

Note that the cleaning pad 16 may be kept in constant contact with the surface of the heat fixing roller filter. In this case, the solenoid 19 is unnecessary, and the spring 18 is locked so as to bias the cleaning pad 16 in a direction to contact the heat fixing roller.

When the solenoid 19 is not energized, the heat fixing roller 3 is
in a non-cleaning position spaced from the surface. The solenoid 19 is turned on and off by the valley sensor that controls the solenoid 10.
, and the anti-offset liquid supply means is in the first position li.
f and is turned off when the means is placed in the second position as shown in FIG.

In other words, when the felt 7 is applying glue oil to the heating fixing roller 3, the cleaning vane 16
is located in a non-cleaning position away from the roller 3,
When the felt 7 is separated from the roller 3, cleaning is performed by placing the cleaning pan 16 in the cleaning position where it is in contact with the roller 6.

That is, when the sheet S is detected by a sheet sensor (not shown) located on the near side of the sheet path 0, the felt 7 assumes the first position, and at the same time, the cleaning pad 16 assumes the non-cleaning position. In addition, in response to a signal detected by a sheet sensor (not shown) located behind the pair of rollers in the sorting path 0 that the sheet S has passed through the nip, the felt 7 takes the second position, and the cleaning pad 16 moves to the second position. take a position.

As described above, in the present invention, when the roller pair 1 is not passing the paper, the felt 7 serving as the offset prevention liquid supplying member is
is moved to a position away from the circumferential surface of the heating roller 6, cutting off the supply of glue oil to the roller, so that wasteful consumption of the oil can be suppressed.

In addition, this heat fixing device is equipped with an offset prevention liquid supplying means (IJ2K) and a cleaning means.
There is no need to provide a cleaning function to the offset prevention liquid supply means, and clogging of the offset prevention liquid supply means can be prevented.

Further, in this heat fixing device, the cleaning pad 16
Since the pad 16 and the felt 7 move relative to each other, the pad 16
Compared to the case where the pad 16 is fixedly provided, the silicone oil applied by the felt 7 is not constantly removed by the pad 16, so the consumption of silicone oil can be reduced.

Next, a 1 m embodiment of the present invention will be described based on FIG. 6. In this embodiment, the same members as those in the previous embodiment are designated by the same reference numerals, and the explanation thereof will be omitted.

The felt 7, which is an offset prevention liquid supply member, is integrally supported by one end 31a of a support member 31 having an inverted shape, and the other end 31a of the support member 31, and a cleaning pad 16 which is a cleaning member. This L-shaped support member 31 is swingably provided around a pivot shaft 33, and the other end 3
1b is connected to a spring 64 that swings and urges the support member 31 in a counterclockwise direction, and one end portion 51a of the spring 64 is connected to the spring 64.
65 is connected to Rennoi. This solenoid 35
When turned on, the support member 31 swings clockwise.

The solenoid 65 is turned off by a seat detection signal from a seat sensor (not shown) located in front of the opening to the opening 1 of the seat passage 0. When the solenoid 35 is turned off, the support member 61 is swung counterclockwise about the shaft 36 by the elasticity of the spring 34. The felt 7 is supported by one end 31a of the support member 31 and is υ.
# is moved to the first position where it contacts the circumferential surface of the heating roller 3, and Noricon oil is supplied to the circumferential surface of the roller. Further, at this time, the cleaning hat 16 supported by the other end 31b of the supporting portion 4]31 moves to a non-cleaning position away from the circumferential surface of the roller 3. Next, when the sensor detects that the sheet S has passed through the nip, the solenoid 35 is turned on in response to the detection signal, causing the support member 61 to swing clockwise about the shaft 63.

As a result, the felt 7 moves to the second position away from the circumferential surface of the roller 6, and the supply of silicone oil to the circumferential surface of the roller is cut off. Further, when the supporting portion 31 swings clockwise, the cleaning pad 16 supported by the other end 31b moves to a cleaning position where it contacts the circumferential surface of the roller 6, and the cleaning pad 16 is moved to the cleaning position where it contacts the peripheral surface of the roller 6, and Clean.

In this way, in this embodiment, the offset prevention liquid supply member and the cleaning unit are supported by one support 61, and the means for moving them relative to each other is provided by one solenoid 3.
5, the structure of the apparatus itself can be simplified, and the control means for the cleaning means and offset prevention liquid supply means can be simplified.

Incidentally, when the copying machine is not in operation, if both the off-safety prevention liquid supplying member and the cleaning member are separated from the surface of the heating roller, damage to the surface of the roller due to assimilation of toner can be prevented. In this case, the positions of the spring 9, which is the moving means, and the solenoid 10 in FIG. 1 are switched, and the solenoid 10 is turned on only when paper is passed, and is operated to place the felt 7 in the first position.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the heat fixing device of the present invention, and FIG.
FIG. 3 is a schematic operational view showing the temperature state when paper is not being passed, and FIG. 3 is a schematic side view showing another embodiment of the heat fixing device of the present invention. 1...Heating roller pair, Ro...Heating roller, 6...
Tank, 7..., Felt, 8, 17.31... Supporting member, 9.18°64... Pie, 10.19. ! +
5...Solenoid, 16...Cleaning pad. ■(Liu/Q ■Z#, J

Claims (1)

[Scope of Claims] 1. A fixing device having a pair of heat fixing rollers and an anti-offset liquid supplying means for supplying and coating an anti-offset liquid onto the circumferential surface of the roller that comes into contact with at least a visible image. - Offset prevention liquid supply means selectively positioned at a first position for supplying offset prevention liquid to the roller and a second position for not supplying the offset prevention liquid; When paper is being fed, the offset prevention liquid supplying means is located at the first position, and when the pair of heating and fixing rollers is not passing paper, the offset prevention liquid supplying means is located at the second position. A heating fixing device comprising a moving means, and supplying an anti-sorting liquid to the rollers only when the pair of heating and fixing rollers passes the paper. 2. A pair of heating and fixing rollers. , Mf is at least tangent to the visible image.
In a heating fixing device, the heating fixing device has an offset prevention liquid supplying means for supplying and applying an offset prevention liquid to the circumferential surface of the roller, which has a first position where the offset prevention liquid is supplied to the roller, and a second position where the offset prevention liquid is not supplied to the roller. When the pair of heat-fixing rollers and the offset prevention liquid supply means are selectively positioned at the first position, the offset prevention liquid supply means is positioned at the first position, and the pair of heat-fixing rollers The present invention is characterized by comprising a moving means for positioning the anti-offset liquid supply means to a second position when the pair is not passed through, and a means for cleaning the surface of the roller. Heat fixing device. 3. In the invention set forth in claim 2, the cleaning means includes means for selectively moving the cleaning member to a non-cleaning position and a cleaning position, and the offset prevention liquid supply means is a first When the cleaning member is in the second position, the cleaning member is located in a non-cleaning position, and when the off-flash prevention liquid supply means is in the second position, the cleaning member is located in the cleaning position. 4. According to the invention described in claim 2 or 6, a cleaning member in the cleaning means and a coating member for directly applying the anti-offset liquid to the roller in the anti-offset liquid supply means. A heating fixing device characterized in that a means for moving a cleaning means and a means for moving an off-knot prevention liquid supplying means are constituted by one driving means. .