JPH01314276A - Mold releasing agent supply device - Google Patents

Abstract

PURPOSE:To obtain the uniform supplying quantity of mold releasing agent by forming the cross section of the leading edge of a blade on a side in contact with a roll in a circular arcuate shape and specifying the radius of curvature thereof. CONSTITUTION:A measure blade 16 which regulates the quantity of oil 13 adhering to the surface of a metering roll 15 and measures it so as to be a constant quantity is disposed on the surface of the metering roll 15 so that it may press- contact there with a specified press-contacting force. In such a case, the cross section of the leading edge of the blade 16 on the side in contact with the roll is formed in the circular arcuate shape and the radius of curvature R is set 0.05<=R<=0.3mm. Thus, the appropriate supplying quantity of mold releasing agent can be obtained and the uniform supplying quantity thereof can be also obtained in the axial direction of the roll.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an improvement in a release agent supply device used in a fixing device of an electrophotographic copying machine or the like.

[Prior Art] Conventionally, as shown in FIG. 8, the above-mentioned fixing device has a fixing roll 50 and a pressure roll 51 in pressure contact with each other, and unfixed toner @52 is present between the two rolls 50 and 51. Some copy paper 53 is passed through to fix the unfixed toner image 52 onto the copy paper 53 by heat and pressure.

At that time, the surface of the fixing roll 50 comes into contact with the unfixed toner image 52, so that the toner remains constant at the time of fixing.
There may be an offset to Therefore, a release agent such as silicone oil is applied to the surface of the fixing roll 50 by a release agent supplying device 54 to prevent the toner from being offset on the surface of the fixing roll 50 (
JP-A-55-7795@, JP-A-56-5576, etc.).

As shown in FIG. 8, the release agent supply bag M54 is pumped up by an oil pan 56 containing oil 55, a metering roll 57 that pumps up the oil 55 from the oil pan 56, and a metering roll 57 that pumps up the oil 55 from the oil pan 56. A measuring blade 58 that scrapes off the oil 55 that has been measured, and a metering blade 58 that scrapes off the oil 55 that has been measured.
5 to the fuser roll 50
It is composed of. The metering roll 57 and the donor roll 59 are rotatably supported, and the metering roll 57 is in contact with the donor roll 59, and the donor roll 59 is in contact with the fixing roll 50, respectively, with a predetermined pressure contact force. There is.

Now, when the fixing roll 50 rotates with the copying operation of the copying machine, the donor roll 59 that is in pressure contact with the fixing roll 50 and further the metering roll 57 rotate in the direction of the arrow. and,
The oil 55 in the oil pan 56 is pumped up by the metering roll 57, and an oil film of a predetermined thickness is formed on the surface of the metering roll 57 by the metering blade 58. The oil film formed to a predetermined thickness on the surface of the metering roll 57 is transferred to the surface of the donor roll 59 by contacting the donor roll 59, and is further supplied from the surface of the donor roll 59 to the fixing roll 50. Ru.

The appearance of the oil supplied to the surface of the fixing roll 50 is as follows:
If it is too small, toner offset will occur, and if it is too large, oil will adhere to the copy paper 53 and cause oil smearing. Therefore, the level of the oil 55 supplied by the mold release agent supply device 54 needs to be an appropriate level within a predetermined range. Furthermore, if the suspension of the oil 55 supplied to the fixing roll 50 is uneven in the longitudinal direction of the fixing roll 50, an offset may occur in a part of the fixing roll 50. Oil 5 by 54
5 needs to be uniform over the longitudinal direction of the fixing roll 50.

[Problems to be Solved by the Invention] However, the above prior art has the following problems. That is, in the case of the release agent supply device 54, the blade 58 is simply placed on the surface of the metering roll 57.
The problem is that the amount of oil 55 applied to the surface of the metering roll 57 is kept constant by bringing the blades into contact with each other, so that the amount of oil supplied varies depending on the edge shape of the tip of the blade 58, etc. was there. In particular, when the metering roll 57 or the blade 58 is replaced, there is a problem that an appropriate amount of oil applied and a uniform amount of oil cannot be obtained in the longitudinal direction.

[Means for Solving the Problems] Therefore, the present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to provide a mold release agent supply device which can supply a uniform release agent in the axial direction of the roll.

That is, the present invention includes a plurality of rolls that rotate with their surfaces in contact with each other, and supplies the mold release agent to the first roll, and also supplies the mold release agent by bringing the blade into contact with the surface of the first roll. In a mold release agent supply device configured to regulate the amount of mold release agent and to supply the mold release agent via a roll that contacts the first roll, the tip of the blade on the side that contacts the roll; The edge is formed to have an arcuate cross section, and the radius of curvature R thereof is set to satisfy 0.05≦R≦0.3 mm.

The plurality of rolls used include, for example, two rolls, a metering roll and a donor roll, but are not necessarily limited to this, and may be a combination of three or more rolls.

The donor roll is arranged so as to come into contact with the surface of the fixing roll, for example, but is not limited thereto, and may of course be arranged so as to come into contact with a pressure roller.

In addition to the above configuration, the surface roughness of the first roll may be set so that the 10-point average roughness R satisfies 1≦RZ≦6 μm.

[Function] In this invention, the inventors conducted various tests to find out what conditions should be met in order to uniformly supply the mold release agent at a predetermined rate, and as a result, the above conditions were satisfied. clarified that it is sufficient to satisfy the following.

[Example] The present invention will be explained below based on illustrated embodiments.

FIG. 1 shows a fixing device to which an embodiment of a release agent supply device according to the present invention is applied. In the figure, reference numeral 1 denotes a fixing device, and this fixing device 1 consists of a fixing roll 2 and a pressure roll 3 that comes into pressure contact with the fixing roll 2. The fixing roll 2 is constructed by coating the surface of a metal roll 4 with a relatively thick elastic layer 5 made of heat-resistant synthetic resin or the like. Moreover, the pressure roll 3 is
It is constructed by thinly coating the surface of a metal roll 6 with an elastic layer 7 made of heat-resistant synthetic resin or the like. The fixing roll 2 and the pressure roll 3 are heated to a predetermined temperature by a heater 8.9 housed therein, and the copy paper 11 has an unfixed toner image 10 formed therebetween. The unfixed toner image 10 is fixed onto the copy paper 11 by heat and pressure.

A release agent supply device 12 is provided near the fixing roll 2 to apply a release agent such as silicone oil to the surface thereof.

The mold release agent supply device 12 includes a plurality of rolls that rotate with their surfaces in contact with each other, and supplies the mold release agent to the first roll, and also contacts the surface of the first roll with a blade. The above-mentioned No. 1
The mold release agent is configured to be supplied through the roll that contacts the second roll.

That is, this mold release agent supply device 12 includes an oil pan 14 containing oil 13 as a mold release agent.
A metering roll 15 for pumping up 3 is provided. The metering roll 15 is formed of a cylinder made of metal such as stainless steel. A metering blade 16 is disposed on the surface of the metering roll 15 so as to control the amount of oil 13 adhering to the surface of the metering roll 15 and measure it to a constant amount with a predetermined pressure. has been done. As shown in FIG. 2, this metering blade 16 is held with its upper end fitted into a blade channel 18 provided in a blade holder 17, and is disposed over the entire length of the fixing roll 2 in the longitudinal direction. It is set up.

Further, a donor roll 19 is in contact with the surface of the metering roll 15, and one of the donor rolls is also in contact with the surface of the fixing roller 2. Donor roll 19
In this example, an elastic layer 21 is formed on the surface of a metal roll 20.

The metering roll 15 and one donor roll are rotatably arranged.

By rotationally driving the fixing roll 2, the donor roll 19 in contact with the surface of the fixing roll 2 and further the metering roll 15 are rotated. Then, the oil 13 in the oil pan 14 is transferred to the metering roll 15.
The metal is drawn up by the metal ring and adheres to the surface of the metering roll 15. The oil 13 adhering to the surface of the metering roll 15 is metered by a certain amount by the metering blade 16 to form a film having a predetermined thickness. extra oil 13
is returned into the oil pan 14. The oil film formed on the surface of the metering roll 15 is transferred to the surface of the donor roll 19 that contacts the metering roll 15,
The oil film transferred to the donor roll 19 is applied and supplied to the surface of the fixing roll 2 that contacts the donor roll 19.

In such a release agent supply device 12, the fixing roll 2
The amount of oil 13 supplied to the metering roll 13 is approximately determined by the amount of oil on the surface of the metering roll 15 regulated by the metering blade 16. That is, the metal ring roll 1
If the thickness of the oil film formed on the surface of the fixing roll 5 is not constant or uneven along the longitudinal direction of the roll 15, the oil 13 supplied to the surface of the fixing roll 2 may
The weather will also be uneven.

Therefore, the present inventors have developed a stable and uniform oil supply T.
In order to obtain this, we made prototypes with various changes in the shape of the tip edge of the metering blade, the surface condition of the metering roll, the material of the metering blade, the pressing force, etc., and conducted tests on oil supply performance.

As a result, the present inventors have clarified that the most important factor affecting the amount and uniformity of oil application is the shape of the tip of the metering blade. It was also found that the material of the metering blade and the pressure force had little effect on the amount and uniformity of oil application.

Then, as shown in FIG. 3, the tip edge 16a of the metering blade 16 that contacts the metering roll 15 is
It has been revealed that by forming it in an arcuate shape, the amount of oil applied can be maintained at an appropriate amount, and the oil can be applied evenly.

Next, the content of the above test will be explained.

The present inventors prototyped a mold release agent supply device in which the tip edge shape of the metering blade and the surface condition of the metering roll were variously changed, and tested the oil supply performance.

First, the measuring blade 16 is formed using Python rubber (manufactured by DuPont; trade name), and its shape is 3 mm thick.
, the thickness was 10 mm, and the length in the longitudinal direction was 315 mm. As shown in FIG. 2, this metering blade 16 was fitted into a channel 18 of an aluminum holder 17 by about 2 mm and held vertically. Then, this measuring blade 16 is
From the state where the tip of the metering blade is in contact with the surface of the metering roll 15, the metering blade is further fixed at a position where the interference scale is 3 mm (Fig. 4), and the metering blade 1 is placed on the surface of the metering roll 15.
I tried to press 6. The shape of the tip edge of the total 1 blade 16 was made using a mold, but
05 mm was created by cutting. The measuring blade 16 thus produced had a rubber hardness of 65 degrees.

The metaling roll 15 was constructed by polishing the surface of a stainless steel cylinder with a diameter of 25 mm with sandpaper along the axial direction, and measuring the surface roughness in a direction perpendicular to the polishing direction, as shown in FIG. , 10-point average roughness R1, RZ=3.5
It was μm. The surface of this metering roll 15 was cleaned with alcohol.

The donor roll 19 is an aluminum cylinder 20 with a diameter of 49 mm.
A silicone rubber layer 21 with a thickness of 3 mm was provided on the surface and the diameter was 25 mm. The hardness of the silicone rubber was 40 degrees, and the surface roughness was R1-10 μm.

As oil 13, a mercapto-modified silicone oil having a mercapto functional group at the end was used. The oil pan 14 had a depth of 10 mm, was lined with a 4 mm thick wick, and contained 50 g of the oil 13.

On the other hand, as the fixing roll 2 that fixes the toner image,
A rubber layer 5 made of pyton rubber was provided on the outer peripheral surface of an aluminum roll 4 with a thickness of 1.5 mm and a diameter of 5 Q mm. Further, as the pressure roll 3, a metal roll 6 with a PFA (tetrafluoroethylene perfluoroalkyl vinyl copolymer) layer 7 baked to a thickness of 30 μm on the outer peripheral surface was used. The surface temperature of the fixing roll 2 is 200°C, the surface temperature of the pressure roller 3 is 180°C,
Each was set. Further, the surface speed of both rolls 2.3 was 80 mm/sec.

The metering roll 15 was brought into pressure contact with the donor roll 19 at a contact force of 0.5 kg/cm, and the donor roll 19 was also brought into contact with the fixing roll 2 at a pressure contact force of 0.5 kg/cm.

The fixing device 1 and release agent supply device 12 configured as described above are incorporated into a copying machine; Fuji Pillox 6800, and as the copy paper 11, Fuji Xerox Office Supply Co., Ltd.'s L paper < A4 size) is fed horizontally. The following experiment was conducted.

Experiment 1 The radius of curvature R of the tip edge of the metering blade 16 is 010
．． 0.5, 0.1, 0.2, 0.3, and 0.4 mm, 2,000 copies were made at a time, and the amount of oil supplied to the fixing roll 2 per sheet was measured. FIG. 6 shows the results.

As is clear from this result, the radius of curvature R of the tip edge 16a of the metering blade 16 is set to 0.05≦R≦Q, 3 m.
By setting the oil supply port to the desired 5 to
It was found that the amount could be kept constant within the range of 9 μg/Copy. Furthermore, when the surface of the fixing roll 2 coated with the oil 13 was observed, it was found that the oil was uniformly coated along the longitudinal direction of the fixing roll 21.

Experiment 2 The radius of curvature R of the tip edge of the metering blade 16 is 0,
1mm1. : Fixed, and the surface roughness R2 of the metering roll 15 is 0.5.1.3.5 with a 10-point average roughness R7.
6.7.8μm, and 2000 copies are made at a time, and the oil supply port is supplied to the fixing roll 2 for each copy, and the oil is supplied along the longitudinal direction of the fixing roll 2 at the initial stage. In order to determine whether or not the fixing was done uniformly, the number of oil streaks formed on the surface of the fixing roll 2 was measured. FIG. 7 shows the results.

As is clear from this figure, by setting the surface roughness of the metering roll 15 to 1≦R1≦6 μm with a 10-point average roughness R7, the oil supply ω is desirably 5 to 9 μm.
g/Copy's t! It has been found that the fixing roll 2 can be maintained within the vicinity of the fixing roll 2, and that the oil supply property along the longitudinal direction of the fixing roll 2 is also uniform.

In the above experimental example, the case where the silicone rubber layer 21 was provided on the surface of the aluminum cylinder 20 was explained as an example of the donor roll 19, but the elastic layer 21 was provided around the metal cylinder 20. , furthermore, a PFA layer of 10 to 1 on the outer peripheral surface.
A material coated with a thickness of 00 μm may also be used. In such a case, cleaning performance of the donor roll 19 is improved.

(Effects of the Invention) This invention has the above-described configuration and operation, and can obtain an appropriate amount of supply of mold release agent, and moreover, can uniformly supply the mold release agent a in the axial direction of the roll (a). It is possible to provide a mold release agent supplying device capable of supplying a mold release agent.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing a fixing device to which a release agent supply device according to the present invention is applied, Fig. 2 is a side view showing a metering blade, Fig. 3 is an enlarged view of section A in Fig. 2, and Fig. 4 is an explanatory diagram showing the contact state of the metering blade to the metering roll, FIG. 5 is a perspective view showing the metering roll, and FIG. 6 is a diagram showing the relationship between the radius of curvature of the tip edge of the metering blade and the oil supply port. Figure 7 is a graph showing the relationship between the surface roughness of the metering roll, the amount of oil supplied, and the number of oil streaks, and Figure 8 is a configuration diagram showing a fixing device to which a conventional release agent supply device is applied. be. [Explanation of symbols] 12...Releasing agent supply device 13...Oil 14...Oil pan 15...Metering roll 16...One metering blade...Donor roll Fig. 4 Fig. 6 Figure 7

Claims (2)

[Claims] (1) Equipped with a plurality of rolls that rotate with their surfaces in contact with each other, a mold release agent is supplied to the first roll, and a mold release agent is supplied by contacting the surface of the first roll with a blade. In a mold release agent supply device that regulates the amount of the agent and supplies the mold release agent through a roll that contacts the first roll, the tip edge of the blade on the side that contacts the roll is cut in section. Formed in an arc shape, its radius of curvature R
A mold release agent supply device characterized in that R is set so that 0.05≦R≦0.3 mm. (2) The release agent supply device according to claim 1, wherein the surface roughness of the first roll is set so that the 10-point average roughness R_Z satisfies 1≦R_Z≦6 μm. .