JP4585668B2 - Fixing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fixing device having a planar heater (hereinafter abbreviated as a surface heater) in which a planar heating element is formed on an insulating substrate.
[0002]
[Prior art]
Generally, in an image forming apparatus such as a printer, a film is used as a fixing device that transfers a toner image formed by an image forming unit onto a recording sheet, and heats and pressurizes the toner image to fix it as a permanent image on the recording sheet. There is a type fixing device.
[0003]
This film-type fixing device uses a surface heater in which a surface heating element is provided on a ceramic substrate. The surface heater is supported by a support member having a substantially C-shaped cross section, and a cylindrical film is formed on the outer periphery thereof. A member is mounted. The pressure roller is in pressure contact with the surface heater through this film, and a recording sheet carrying an unfixed toner image passes between the pressure roller and the film, thereby melting the toner image. To fix on the recording sheet.
[0004]
In such a fixing device, the electrode of the ceramic surface heater is formed at the end of the ceramic substrate, and the connector is supported by the surface heater as shown in FIG. The supporting member is configured to come into contact with the supporting member by sliding insertion from a direction orthogonal to the longitudinal direction of the surface heater. By sliding and inserting into the support member, the contact terminal portion included in the connector is brought into contact with and electrically contacted with the surface heater, that is, the electrode formed on the insulating substrate.
[0005]
In FIG. 7, an electrode 62 is printed on an insulating substrate 61, and the insulating substrate 61 is supported by a support member 65 formed of a heat-resistant resin such as LCP or PPS. A contact 64 constituting the connector is enclosed in a connector housing (not shown), and a contact terminal portion 63 which is a part of the contact 64 is brought into contact with and electrically connected to the electrode 62 with sufficient contact pressure. Yes.
[0006]
[Problems to be solved by the invention]
When the contact is electrically connected to the electrode 62 formed on the insulating substrate 61 supported by the support member 65 by sliding insertion, the connector is inserted at a large angle. Then, as in the case of fitting when the insertion angle is large in FIG. 7B, the tip edge of the contact 64 may interfere with the electrode 62 and part A, and the electrode may be damaged.
[0007]
An object of the present invention is to provide a power supply device and a heating device for a heating device that can correct the insertion angle of the connector depending on the shape of the support member and the contact and can prevent the electrodes from being damaged by the contact edge. Is to provide.
[0008]
[Means for Solving the Problems]
The present invention for solving the above-mentioned problems is provided on a cylindrical film member, an insulating substrate, a heating element provided on the substrate, and the substrate at a longitudinal end of the substrate. An electrode part electrically connected to the heating element, a heater whose surface opposite to the surface on which the heating element and the electrode part are provided contacts the inner surface of the film member, and the film It is provided inside the member and holds the surface of the heater on which the heating element and the electrode part are provided with a holding surface, and a part facing the electrode part is cut out so that the electrode part is exposed. A heater guide, a pressure roller that forms an area for fixing a recording sheet carrying an unfixed toner image together with the heater via the film member, a U-shaped housing section, Housing part An electrode spring contact provided on the inner surface and in contact with the electrode portion, and an urging direction of the electrode spring contact provided on the inner surface of the housing portion facing the inner surface provided with the electrode spring contact. A support spring contact for biasing the heater from a surface opposite to the surface on which the electrode portion is provided toward the holding surface of the heater guide. The housing in which the heater and the heater guide are provided with the electrode spring contact by mounting the heater held by the heater guide with the U-shaped opening side as a head. A fixing device including a connector sandwiched between an inner surface of the portion and the support spring contact, and the electrode spring contact with the electrode portion to supply power to the heating element. Wherein the contact pressure it contacts is set higher than the contact pressure of the electrode spring contacts.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
1 to 4 show a first embodiment.
[0010]
FIG. 1 shows a schematic configuration of a ceramic surface heater. (A) is sectional drawing of a ceramic surface heater, (b) shows the surface in which the heat generating body is formed, (c) has shown the surface opposite to the surface which (b) has shown.
[0011]
The ceramic surface heater includes a ceramic insulating substrate 7 such as SiC, AlN, and Al ₂ O ₃ , heating elements 10, 11, and 12 formed on one surface of the insulating substrate 7 by paste printing or the like, and the heating element 10. , 11 and 12 is formed of a protective layer 13 such as glass.
[0012]
The heating element 10 includes a portion 10a that generates heat when electric power is supplied, a conductive portion 10b that connects the electrode portions 10c and 10d and the heating element 10a, and electrode portions 10c and 10d to which electric power is supplied via a connector. Has been.
[0013]
The heating element 11 includes a portion 11a that generates heat when power is supplied, a conductive portion 11b that is connected to the electrode portions 10c and 11d, and an electrode portion 10c and 11d that is supplied with power through a connector. .
[0014]
The heating element 12 includes a portion 12a that generates heat when power is supplied, a conductive portion 12b that is connected to the electrode portions 10c and 12d, and electrode portions 10c and 12d that are supplied with power via a connector.
[0015]
The ceramic heater is supported by a heater guide 1 as shown in FIG. The surface on which the heating elements 10, 11, 12 of the ceramic heater are printed is received and supported by the heater guide 1.
[0016]
FIG. 2 is a view particularly showing a fitting portion with the connector. A portion of the heater guide corresponding to the electrode portion 6 (10c, 10d, 11d, 12d) is cut out so that the electrode portion is exposed. Further, in order to fill a step between the ceramic heater and the heater guide 1, a connector spacer 8 is provided only at a place where the connector 3 is fitted on the surface side facing the support surface of the heater guide.
[0017]
On the other hand, the connector 3 is formed such that the opening width in the vertical direction of the front end opening of the inner contact portion 2 is wider than the thickness D of the heater guide 1. Further, a notch 1 a is formed corresponding to the electrode portion 6 of the heater guide 1.
[0018]
As illustrated, the heater guide 1 has no notch where the connector 3 is fitted and there is no electrode between the electrodes.
[0019]
As shown in FIGS. 3 (a) and 4 (a), the connector 3 is slid into and inserted into a ceramic heater supported by a heater guide, so that the contact 2 heats the ceramic substrate 7 and the electrode 6 to the heater. The guide 1 and the connector spacer 8 are sandwiched together.
[0020]
3 is a sectional view of the contact portion, and FIG. 4 is a sectional view of the housing portion. When the connector 3 is fitted, the electrode spring contact 4 is in electrical contact with the electrode 6 of the ceramic heater at a predetermined contact pressure, and the support spring contact 5 at a position facing the electrode spring contact 4 is the connector spacer. 8 is in contact with a predetermined contact pressure. Here, by making the contact pressure of the support spring contact 5 higher than the contact pressure of the electrode spring contact 4, the electrode spring contact 4 is always in contact with the electrode 6 and an electrically stable connection can be established.
[0021]
As shown in the present embodiment, only the electrode portion 6 is cut out of the heater guide portion, so that the connector 3 is fitted into the electrode 6 by sliding insertion as shown in FIGS. 3 (b) and 4 (b). When the contact 2 is electrically connected, even if the insertion angle of the connector 3 is inserted at a large angle, the angle is first corrected by the positional relationship between the housing of the connector 3 and the heater guide 1 (the open end of the connector 2 is the heater). The contact with the top surface of the guide 1 and the contact of the inner bottom surface of the housing with the corner of the connector spacer 8 restricts the insertion of the connector 3, and if it does not return to the normal posture, further insertion is impossible). The leading edge of 2 does not contact the electrode part 6.
[0022]
Further, the edge of the contact portion 2 is corrected so as not to contact the electrode portion due to the positional relationship between the contact portion 2 and the notch portion 1a of the heater guide 1. Therefore, even if the insertion angle of the connector is large, the heater guide shape and the connector shape can be corrected so that the contact edge does not interfere with the electrode portion and does not interfere with the electrode portion when the connector is inserted. .
[0023]
( Reference example )
5 and 6 show a reference example .
[0024]
The points overlapping with the first embodiment are omitted.
[0025]
As shown in FIGS. 5A and 6A, the ceramic heater is supported by the heater guide 21 as a receiving surface that faces the surface on which the heating elements 10, 11, and 12 are printed.
[0026]
The contact portion 22 included in the connector 24 constituting the fitting portion of the connector 24 with respect to the heater guide 21 corresponds to a notch portion 21a that is upside down from the first embodiment, and is a spring contact for an electrode. 23 is formed. The contact portion 22 sandwiches the ceramic substrate 7 and the electrode 6 together with the heater guide 21 by slidingly inserting and fitting the connector 24 to the ceramic heater supported by the heater guide 21.
[0027]
FIG. 5 shows a sectional view of the contact portion, and FIG. 6 shows a sectional view of the housing portion. By fitting the connector 24, the electrode spring contact 23 is in electrical contact with the electrode 6 of the ceramic heater at a predetermined contact pressure. By adopting a configuration in which the contact portion 22 is sandwiched together with the heater guide, the electrode spring contact 23 is always in contact with the electrode 6 and an electrically stable connection can be made.
[0028]
Here, the heater guide 21 has a protruding portion 21 b that holds the ceramic substrate 7, and the position of the protruding portion 21 b corresponds to the position of the electrode portion 6. In addition, the protruding portion 21b of the heater guide 21 is larger than the protruding portion of the electrode portion between the electrode portions, that is, the portion where the insertion of the housing portion 24 is corrected.
[0029]
According to this reference example , as shown in FIG. 5B and FIG. 6B, when the contact 24 is electrically connected by fitting the connector 24 to the electrode 6 by sliding insertion, the connector 24 Even when the insertion angle is inserted at a large angle, the angle is first corrected by the positional relationship between the housing 24 and the heater guide 21, and the tip edge of the contact portion 22 does not contact the electrode portion 6.
[0030]
Further, due to the positional relationship between the contact portion 22 and the overhang portion 21b of the heater guide 21, the edge of the contact portion 22 is corrected so as not to contact the electrode portion.
[0031]
Therefore, even if the connector is inserted at a large angle, the shape of the heater guide and the shape of the connector can be corrected so as to achieve normal fitting without damaging the electrode portion.
[0032]
【The invention's effect】
As described above, according to the present invention, the heater guide holds the surface of the heater where the heating element and the electrode portion are provided by the holding surface, and the portion facing the electrode portion is notched so that the electrode portion is exposed. Since the contact pressure of the support spring contact of the connector is set higher than the contact pressure of the electrode spring contact, the connector can be mounted without damaging the electrode portion, and the electrode spring contact of the connector is always at the electrode portion. It is possible to make an electrically stable connection by touching .
[Brief description of the drawings]
1A and 1B show a heating device according to a first embodiment of the present invention, in which FIG. 1A is a cross-sectional view, FIG. 1B is a cross-sectional view of FIG. 1A, and FIG. Figure.
2 shows the positional relationship between the heating device of FIG. 1 and the connector part, (a) is a plan view, (b) is a sectional view taken along the line bb of (a), and (c) is c of (a). -C arrow sectional drawing.
FIGS. 3A and 3B are fitting diagrams of the connector according to the first embodiment. FIG. 3A shows a case where normal fitting is performed, and FIG. 3B shows a case where a fitting angle exceeding a proper fitting angle is large.
FIGS. 4A and 4B are diagrams illustrating fitting of the connector according to the first embodiment, where FIG. 4A illustrates a case where normal fitting is performed, and FIG. 4B illustrates a case where an insertion angle for fitting beyond a proper fitting angle is large.
FIGS. 5A and 5B show a reference example, in which FIG. 5A shows a normal fitting, and FIG. 5B shows a case where a fitting angle exceeding a proper fitting angle is large.
6A and 6B show a reference example, in which FIG. 6A shows a normal fitting, and FIG. 6B shows a case where a fitting angle exceeding a proper fitting angle is large.
7A and 7B show a fitting state of a connector of a conventional example, in which FIG. 7A shows a normal fitting state, and FIG. 7B shows a case where an insertion angle to be fitted beyond a proper fitting angle is large.
[Explanation of symbols]
1,2,65 Heater guide 2,22,64 Contact part 3,24 Connector housing 4,23,63 Spring contact for electrode 5 Spring contact for support 6 Electrode part 7 Ceramic substrate 8 Connector spacer 10, 11, 12 Heating element

Claims (1)

A tubular film member;
An insulating substrate; a heating element provided on the substrate; and an electrode part provided on the substrate at a longitudinal end of the substrate and electrically connected to the heating element, A heater whose surface opposite to the surface on which the heating element and the electrode portion are provided contacts the inner surface of the film member;
It is provided inside the film member, the surface of the heater on which the heating element and the electrode portion are provided is held by a holding surface, and the electrode portion is exposed at a portion facing the electrode portion. A notched heater guide,
A pressure roller that forms an area for fixing a recording sheet carrying an unfixed toner image together with the heater via the film member;
A U-shaped housing section, an electrode spring contact provided on the inner surface of the housing section and in contact with the electrode section, and an inner surface of the housing section provided with the electrode spring contact. The holding surface of the heater guide is provided on the inner surface and has an urging force in a direction opposite to the urging direction of the electrode spring contact, and the heater guide from the surface opposite to the surface on which the electrode portion is provided. A spring contact for urging toward the heater, and the heater held by the heater guide with the U-shaped opening side attached to the heater. The heater guide is sandwiched between the inner surface of the housing portion provided with the electrode spring contact and the support spring contact, and the electrode spring contact contacts the electrode portion to supply power to the heating element. To do And the connector,
In a fixing device having
The fixing device, wherein a contact pressure of the supporting spring contact is set higher than a contact pressure of the electrode spring contact.

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