JPS5831154Y2 - Heating roll type fixing device - Google Patents

Description

[Detailed Description of the Invention] The present invention is based on electronic photocopying, heating roll type fixing using a heat roller, etc.

・1 This type of fixing device (≠1.., 1.1, l”
As shown in the figure, it is equipped with a pair of fixing rolls, for example, a pair of heating rolls 1 and a pressure roll 2, and between these rolls 1 and 2, a toner image 3 is transferred. The horn image 3 is fixed on the transfer mt44 by passing the horn, sail, etc. through a rolling stopper.

These fixing roll pairs are made of a material that repels viscous materials,
For example, the surface of the roller is coated with Teflon, and an anti-offset agent supplying member 5 made of a heat-resistant material such as Teflon felt is brought into contact with the heating roll 1 on the side corresponding to the toner image 3 on the transfer medium 4. An anti-offset agent 7 such as silicone oil or low molecular weight polyethylene in an oil pan 6 is supplied to the heating roll 1.

By the way, in the conventional contact roller type fixing device, as shown in FIG. 1, the heating roll 1 is located below, and the anti-offset agent supplying member 5 and the oil pan 6 are located below this. Since the excess offset prevention agent 7 scraped off by the doctor blade 8 naturally falls into the oil pan 6, the offset prevention agent 7. However, the anti-offset agent 7 did not leak to the outside.

However, due to the smaller size and faster speed of copying machines in recent years, the second
As shown in the figure, when the upper roll of the pair of fixing rolls is used as a heating world, the supply member 5 for supplying the anti-offset agent to the heating world is also located on the upper side.1. As shown in FIG. 3, the excess anti-offset agent relative to the heating roll 1 causes a problem in that it leaks to the outside through the lower pressure roll 2.

On the other hand, pressure welding roll? There is also a method of installing an oil pan below, but since this oil pan is far away from the offset preventive agent supply member, there is a drawback that the circulation mechanism for the offset and preventive agent that accumulates in the oil pan becomes difficult. there were.

'': The present invention has the above-mentioned features: A heated roll type in which the holes have been drilled and the upper roll of the pair of fixing rolls is used as a heating roll and an anti-offset agent is applied to this roll. The purpose is to make it possible to easily and accurately prevent and stop the leakage of edge offset preventive agent in mounting equipment.

The configuration is shown below in Figure 1 below), based on the following example:
, 1. ´ ・I will explain next.

11,... 1. ．． 94. . An anti-offset agent supply member 5 is attached to the heating roll 1 located above the pressure roll 2.
and a doctor blade 8 are provided in the same manner as in the conventional example shown in FIG.

The lower end of the anti-offset agent supply member 5 is connected to an anti-offset agent 7 in an oil pan 6 provided at the lower side of the heating roll 1.
Although not shown, the base of the doctor blade 8 is fixed to the machine frame side such as the oil pan 6.

The doctor blade 8 is shorter than the length of the heating roll 1, and oil-absorbing cloths 9, 9 are provided at both ends of the doctor blade 8 for slidingly contacting the heating roll 1. A guide plate 10 located inside 6 is a companion.

The oil-absorbing cloths 9, 9 may be coupled to the doctor blade 8, or may be supported by a guide plate 10.

The oil-absorbing cloths 9, 9 are made of a material that absorbs the anti-offset agent well, such as spongy silicone rubber that is softer than the doctor blade 8.

The excess amount of the offset preventive agent applied by the offset preventive agent 1 to the preventive agent supply member 5 is removed by the doctor blade 8, but this excess offset preventive agent is removed by the oil-absorbing cloth located at both ends of the doctor blade 8. 9, 9, and when it reaches a saturated state, it passes through the guide plate 10 and is collected into the oil pan 6.

In the above embodiment, as shown in FIG.
By making it narrower than the width, it is possible to prevent the oil-absorbing cloths 9, 9 from leaking in the form of drops from the lower pressing roll 2 through the heating roll 1 as a reverse effect.

Furthermore, when a low-viscosity offset preventing agent is used, the offset preventing agent collected on the oil-absorbing cloth 9.9 when the fixing roll pair stops has a low viscosity.
There is a possibility that the oil absorbing cloths 9 and 9 may fall onto the heating roll 1, but in this case, as shown in FIG. It is possible to reduce the amount of coating and prevent leakage through the heating roll 1.

Since the present invention is as described above, leakage of the anti-offset agent can be easily and reliably prevented even in a heating roll type fixing device in which the heating roll 1 is positioned above the pair of fixing rolls.

[Brief explanation of drawings]

FIG. 1 is a configuration explanatory diagram showing a heating roll type fixing device when the heating roll is placed below the pair of fixing rolls, FIG. 2 is a configuration explanatory diagram showing a conventional example, FIG. 3 is a perspective view thereof, and FIG. The figure is a partially cutaway perspective view showing one embodiment of the present invention, FIG. 5 is a plan view of the main part, and FIGS. 6 and 7 are structural explanatory diagrams showing other embodiments. 1 is a heating roll, 8 is a doctor blade, 9 is an oil-absorbing cloth, and 10 is a guide plate.

Claims (1)

[Scope of utility model registration request] □ In a contact roll type fixing device in which an offset preventive agent is applied to the heating roll 1 on the upper side of a pair of fixing rolls, a doctor blade is used to remove an excess amount of the offset preventive agent applied to the heating roll 1. Put oil-absorbing cloths 9, 9 in contact with the heating roll 1 on both sides of the roll 8,
, one end is attached to the bottom surface of the oil-absorbing cloth 9, 9.
A contact roll type fixing device characterized in that a guide plate 10 is provided inside the thread 6.