JPH0455878A - Fusing device - Google Patents

Abstract

PURPOSE:To maintain good toner applying performance and to obtain an excellent applying effect by performing a cleaning action for removing the impurity such as toner, etc., first, by a single oil applying member and then performing a primary oil applying action. CONSTITUTION:A leaf spring 13 which applies loads for pressing the oil applying member 10 to a fixing roller 11 at two or more positions is provided on the load position P2 which is on a downstream side in the rotating direction of the roller 11 among the load positions, then plural holes 18 where oil passes are arranged below the means 17 on the leaf spring 13. Thus, the good oil applying performance is maintained and the offset preventing oil dropped on the leaf spring is rapidly infiltrated in the member 10.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a fixing device comprising a fixing roller and a pressure roller that are in pressure contact with each other, and in which the fixing roller is brought into contact with an oil coating member impregnated with offset prevention oil. Regarding.

[Conventional technology]

2. Description of the Related Art In image forming apparatuses such as copying machines, facsimile machines, and printers, a transfer sheet carrying a toner image is passed between a fixing roller and a pressure roller that are pressed against each other to fix the toner image.

In that case, it is unavoidable that the toner in the toner image is offset to the fixing roller, and in order to prevent this offset, it is well known that an oil application member impregnated with offset prevention oil is brought into contact with the fixing roller using a leaf spring. It is. Furthermore, for cleaning the surface of the fixing roller,
It has already been proposed to arrange a cleaning member separately from the oil application member or to have the oil application member also have a cleaning function.

[Problem to be solved by the invention]

If the cleaning member is arranged separately from the oil applying member, a configuration for arranging the cleaning member is required.
The disadvantage is that the configuration is complicated. In addition, in the case where the oil application member also has a cleaning function, dull substances such as toner and paper dust adhere to the oil application member, which reduces the oil application ability.

Furthermore, in the case where the offset prevention oil is dripped onto the oil application member from above, the offset prevention oil falls onto the leaf spring that presses the oil application member and flows to both ends of the leaf spring.
There is a drawback that it is not guaranteed that the oil will completely penetrate into the oil application member.

The present invention aims to eliminate the above-mentioned conventional drawbacks.

[Means to solve the problem]

The above problem has been solved by the present invention, in which a plate spring is provided on the oil application member that applies a load to press it against the fixing roller at two or more positions, and one of the load positions is located downstream when viewed in the rotational direction of the fixing roller. This problem can be solved by providing a dripping means for anti-offset oil above the load position, and further arranging a plurality of holes for oil passage in the leaf spring below the oil dripping means.

[Function] The oil applying member according to the present invention performs a cleaning action of toner and impurities on the surface of the fixing roller at the first load position, thereby causing the oil application member to clean the toner and impurities on the surface of the fixing roller downstream of the first load position in the rotational direction of the fixing roller. This prevents the adhesion of impurities such as toner and paper dust at a certain second load position, and maintains good oil application performance at this position. Further, the offset prevention oil dropped onto the leaf spring quickly permeates into the oil application member through the plurality of holes provided in the leaf spring.

〔Example〕

In FIG. 1, a fixing roller 1 and a pressure roller 2 are arranged so as to be in pressure contact with each other and rotate in the direction of the arrow. 3 is a heater. A transfer paper 5 carrying a toner image 4 is passed between a fixing roller 1 and a pressure roller 2 via a guide plate 6, and after the toner image is fixed by the pusher, it is sent to the outside of the machine via a pair of discharge rollers 7. It is drained onto the tray. 8 is a separation claw, and 9 is an oil application device constructed according to the present invention.

In FIGS. 1 and 2, one end of the oil application member 10 made of felt material is folded and the fixing roller 11
The other end is immersed in an offset prevention oil 12 such as silicone oil placed in an oil sump 11. A contact portion 10a of the oil application member 10 with the fixing roller 1 is pressed against the fixing roller 1 by a leaf spring 13.

In this case, the contact portion 10a is attached to the leaf spring 1 at two locations: a first load position P1 at the tip of the oil application member 10 and a second load position P2 downstream in the rotational direction of the fixing roller 1.
Pressed more strongly than 3.

14 is a support plate of the leaf spring 13, and 15 is a second cleaning member.

An oil tank 16 is disposed below the oil sump 11, and an oil nozzle 17 is further disposed above the leaf spring 13. The silicone oil 12 in the oil tank 16 is
The oil is supplied by a pump 18 through a conduit 19 to an oil nozzle 17, from which an appropriate amount is dripped. The silicone oil from the oil nozzle 17 drips near the second load position P2 of the leaf spring 13, as shown in FIG.

At the second load position, a plurality of holes 18 are provided in parallel in the axial direction of the fixing roller.

In FIGS. 1 to 3, impurities such as toner and paper powder adhering to the surface of the fixing roller 1 are first dammed up at the first load position P of the application member 10 by the rotation of the fixing roller. ). Therefore, the portion at the second load position P2 is not contaminated with toner or the like, and good oil application performance can be maintained. The toner that has passed through the contact portion 10a without being captured by the contact portion 10a is removed by the second cleaning member 15.
captured by

Further, the silicone oil dripped onto the leaf spring 13 from the oil nozzle 17 passes through the hole 18 provided in the leaf spring 13, reaches the oil application member 10, quickly and evenly penetrates into the member, and then is applied to the fixing roller 1. applied to. As a result, the silicone oil is spread particularly to the portion of the oil application member near the second load position P2, and uniformly applied to the fixing roller.

〔Effect of the invention〕

According to the present invention, a single oil application part first performs a cleaning action to remove impurities such as toner, and then performs the original oil application action, so there is no deposition of toner or impurities at the oil application position, and the product is well-oiled. Excellent toner application performance can be maintained, and since the offset prevention oil dropped from above penetrates into the oil application member through the hole provided in the plate spring, excellent application effects can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a fixing device according to the present invention, FIG. 2 is an enlarged explanation of an oil application device thereof, and FIG. 3 is a perspective view of essential parts of the present invention. 1... Fixing roller 2... Pressure roller 10... Oil application member 13... Leaf spring 18... Hole P□... First load position P2... Second load position

Claims (1)

[Claims] In a fixing device that includes a fixing roller and a pressure roller that are in pressure contact with each other, and in which the fixing roller is brought into contact with an oil coating member impregnated with offset prevention oil, a load is applied to the oil coating member at two or more places to press the oil coating member against the fixing roller. A leaf spring is provided at the position shown in FIG. A fixing device characterized in that a plurality of holes for oil passage are arranged in a leaf spring.