JPS58195867A - Pressure fixation device - Google Patents

Abstract

PURPOSE:To obtain a pressure fixation device which is light in weight, is small in size and permits easy adjustment of pressurizing force, by adjusting the pressurizing force by means of the pressurizing force on a pressurizing lever which converts pressing force to a right angle direction and a pair of pressurizing members screwed to a pressurizing bolt in an inverse screw relation. CONSTITUTION:The pressurizing force of a compression coil spring 63 acting roughly in parallel with upper, middle, lower rolls 51, 55, 58 is converted in a right angle direction by a pressurizing lever 61, and press contact force is generated among the rolls 51, 55, 58 with a guide member 59, then the recording paper passing between the rolls 51 and 55 is subjected to pressure fixation. The pressing force of the spring 63 is adjusted freely by a pressurizing bolt 64 which moves a pair of pressurizing plates 65 in an inverse screw relation when said bolt is turned. The movement of the plates 65 beyond the specified extent is regulated by a nut 66, so that the pressurizing force on the rolls 51, 55, 58 is prevented from increasing higher than the required pressure. The pressure fixation device which is light in weight, small in sizi and by which the pressurizing force is adjusted easily and surely is obtained.

Description

[Detailed description of the invention] [Technical field of the invention] The f! A relates to a pressure fixing device that performs a fixing action by passing a recording paper carrying a toner image between a pair of pressure rolls and crushing the toner image.

[Technical background of the invention and its problems]

As shown in FIGS. 1 and 2, the conventional pressure fixing device includes a lower roll 14 fitted in a lower housing 12 fixed to a base 11 and rotatably supported via a bearing 13, and a lower roll 14 at one end. An upper roll 18 is rotatably supported via a bearing 17 fitted in an upper housing 16 which is rotatably connected to the lower housing 12 via a bin 15.
1, a pressurizing mechanism having a compression coil spring 20 interposed in a bolt 19 is provided at the other end of the lower housing 12 and the upper housing 16, and the lower roll 14 and the upper roll 17 are brought into pressure contact with each other.
, has a structure that generates a predetermined pressure necessary for fixing. In conventional pressure fixing devices, it is necessary to adjust the deflection of the left and right compression coil springs by 1S14 knots each, and it requires skill to adjust the pressure to the same pressure on the left and right sides. There are drawbacks. Also, this conventional pressure foot 7
11 requires a large amount of pressure, so the roll diameter is large, and therefore the weight is large, and the pressure mechanism is provided protruding in the paper passing direction, resulting in a large external size, and is used in facsimiles and copying machines. The disadvantage is that it takes up a large amount of space.

An example of a pressure fixing device having a structure shown in FIGS. 3 and 4 is an example that improves the drawbacks of this follower. The device is
A pair of left and right frames 32 connected by a prismatic body 31
The upper roll 34 is rotatably supported via a bearing 33 fitted in the frame 32, and the bearings 37. A guide member 36 that supports the lower roll 40 is pressed by a plate spring 42 bent by a pressurizing pole 41. Then, the respective rolls are pressed against each other, and the upper roll 34 and the middle roll 39a)
A recording paper having a toner image is passed between them to perform an electrolytic layer action. This conventional pressure fixing device uses three rolls with a smaller diameter than the pressure fixing device shown in FIGS. Since pressure is applied, a small and compact device can be constructed with a relatively light lid. However, a predetermined pressing force necessary for the electrical layer is applied to the frame 3 by a pressing bolt 41 inserted in the frame 32.
Press down on the disc spring 42 from below 7 and let it deflect! 11
However, the number of adjustment points is still two, and in addition, the disc spring 42 has a compression coil used in the conventional four pressure foot devices shown in Figs. 1 and 2. The spring is much thicker than the spring 20 (therefore, it is much more difficult to set the pressing force of the roll, and the work requires a high degree of skill).

In addition, in the conventional pressure fixing devices shown in Figs. 1 to 4, the rolls press against each other due to the heavy load when they are stationary other than when paper is being passed through or during operation, so the service life of the rolls is comparatively long. The shortcoming is that it is difficult to maintain a long life because it is soft and short, and high loads are constantly applied to the bearings. Furthermore, since the rolls are in contact with each other under high pressure, it is often difficult for the recording paper to enter when fusing is attempted, causing jam problems and the recording paper being Another drawback is that when the rolls escape from between the rolls, the rolls collide with each other and noise is generated.

[Purpose of the invention]

The present invention has been made in view of the above points, and its object is to provide a pressure fixing device that is lightweight, small, and compact, and in which the roll pressure force can be easily adjusted. Another object is to provide a reliable pressure fuser that is easy to maintain over a long period of use, with roll and bearing bearings [4fjli].A further object is to provide a reliable pressure fuser that is easy to maintain over a long period of use. To provide a quiet pressure foot* device which ensures reliable entry into a roll and makes no noise when exiting.

[Summary of the invention]

In the present invention, a pair of pressurizing levers are rotatably supported in a mountain half parallel to the meat including the axis of the roll, and one end of each is engaged with a pair of left and right guide members, and consists of a pressure bolt whose position is regulated at the other end of each of the pair of pressure levers, and a pair of pressure plates screwed into desired positions of the pressure bolt in a reverse thread relationship. A pressure member, one end of each of which is locked to each of a pair of pressure plates of the pressure member, and the center thereof is located at the center of the roll. A pressurizing mechanism is provided with a pair of compression springs disposed parallel to # and pressing the other end of each of the pair of pressurizing levers, and the pressurizing force is adjusted by rotating a pressurizing bolt. By doing so, at least the first objective mentioned above is achieved.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 5 and 6.

In FIG. 5, a pair of left and right frames 54 are connected by a prismatic body 53 via an upper roll 5 rear bearing 52.
54 so as to be rotatable. The middle roll 55 is rotatably supported via a bearing 57 mounted on a guide member 56 which is slidably provided in an internal groove of the frame 54. In addition, the lower roll 58 is the middle roll 55.
It is rotatably supported via a bearing 6o mounted on a guide f1459 provided in the same manner as in the case of . In addition, each roll is usually arranged with its axes slightly crossing each other in order to apply a uniform pressing force to all corners of the recording paper to be fixed.
Next, reference numeral 61 denotes a pressure lever, which is rotatably supported via a pin 62 fixed to the prismatic body 53, and has one end that presses against the pressure coil spring 63 (when pressed, it moves in a direction almost perpendicular to it). The other end of the guide section 59(7)-) is pressed upward, thereby generating a pressure force on the adjacent rolls 1iJJK. The pressure coil spring 63 is mounted between the pressure plate 65 and the pressure lever 61. The pressure plate 65 is threadedly connected to the pressure bolt 64, and is supported so that at least one side is unrotatable with the moon pedestal 53 in contact with it, and rotates in the same direction as the pressure bolt by the rotation of the pressure bolt 640. It is movable. The pressure bolt 64 is supported at one end of the pressure lever 61 that is pressed by the compression coil spring 63, for example, by penetrating the bolt 64 so that its position is restricted so that it can move only in the compression direction of the compression coil spring 63. At the same time, the screw directions of the pair of left and right pressure plates 65 are opposite to each other! The compression coil spring 63 has at least one flat surface in the center to adjust the deflection of the compression coil spring 63. 66 is a screw member, for example a nut, which is screwed to the pressurizing lever 64;
This serves to restrict the rotation range of the pressure lever 610.

In the apparatus of the embodiment configured as above, the roll 51.5
A compression coil spring 63 that acts approximately parallel to 5 and 58.
The pressure lever 61 converts the pressing force into a substantially perpendicular direction, and generates a pressing force on the adjacent rollers via the guide member 59, and also connects the shaft 67'1 of the upper roll 51 with a power source (not shown). The upper roll 51 and the middle roll 5
Fixing is performed by passing a recording paper having a toner image on its surface between the toner image and the toner image to be fixed. Pressure force between rolls in g
The 11m adjustment is performed by rotating the pressure bolt 64. That is, by rotating the central flat part of the pressure bolt 64 with a tool such as a wrench, the pair of left and right pressure plates 65 are screwed together with the pressure bolt 64 in the opposite direction with the same thread. The left and right compression coil springs 63 act in the direction of increasing or decreasing the deflection at the same time, and the pressure lever 6
1 and the guide member 59 to simultaneously change the force applied to the left and right details of the rolls, thereby changing the pressure contact force between the rolls.

At this time, the pressure bolt is supported at one end of the pressure lever 61 that is pressed by the compression coil spring 63, for example, in a penetrating manner 5, so as to be able to move in the compression direction of the compression coil spring 63. Therefore, the pressurization generated by the deflection of the compression coil spring 63 is stopped at a position where the force received by the pressurization &65 is always equal on the left and right sides. This means that the pressing force exerted by the compression coil spring 63 on the left and right pressure levers 61 is equal, and therefore the force applied to the left and right shaft portions of the roll is always equal.

In this way, since the pressing force can be adjusted at one location, the work becomes extremely simple.

Furthermore, in this embodiment, since a compression coil spring is used as the compression spring, the spring constant is small, and the work of adjusting the pressing force is further simplified.

In addition, in this embodiment, the nut that engages with the pressure bolt is used to control the rotation range of the pressure lever, so that the pressing force between the rolls when the paper is not passed is reduced. It becomes possible to form a small gap, or it is also possible to form a gap sufficiently smaller than the thickness of the recording paper between the upper roll and the middle roll so that the pressure force does not substantially act. For this reason, it becomes an OT function to apply pressure effectively only when the recording paper is passed through and fixed.
Therefore, if used in a pressure regulator IIF machine that is operated for a considerable period of time even when not passing paper, such as a facsimile machine, the rolls will not come into unnecessary contact with each other under high pressure, so the spout and bearing It has a great effect on extending the life of the machine, and has the advantage of requiring no maintenance over a long period of time and being easily removable. Furthermore, if a small gap tt is provided between the rolls at times other than when paper is being passed through, excess recording paper can be accommodated, and the negative collision between the rolls that conventionally inevitably occurs when the recording paper escapes can be eliminated, resulting in deformation of the rolls. It also has the advantage of eliminating noise.

Note that the present invention is not limited to the Sosei Dormitory example,
It can be implemented by modifying Kusunoki as follows.

For example, the vertical relationship of the rolls may be reversed to that of the embodiment and the pressure mechanism may be provided at the top, in which case the nut for providing the copying barrier between the rolls can be easily operated from above except when paper is being passed. There are advantages.

In addition, in the embodiment, the pressure fixing device is described in which three rolls 1 are combined, but it is obvious that it can also be applied to the pressure fixing unit 51t, which is a combination of two rolls as described in the conventional example. This contributes to making the device smaller and more compact, and also brings about the same effects as the embodiment.

In addition, in the embodiment, a compression coil spring is used as the mechanical spring, but a disc spring may also be used. You can make it smaller and have a similar effect to pressure stiffness.

Furthermore, regarding the pressure bolt, in the example, the central flat part was rotated with a spanner etc. to adjust and set the roll pressure contact force, or the end of the pressure bolt was slotted and the frame was A hole is drilled in the extension direction of the pressure bolt, and the pressure bolt can be rotated from the surface using a screwdriver through the hole, which makes assembly of the device even easier, and allows for facsimile IJ JP bales. The difficulty of adjusting the pressure vI4 after installation in a photographic machine is also improved.

〔Effect of the invention〕

As explained above, according to the present invention, the pair of guide members is rotatably supported in a plane parallel to the plane including the axis of the roll, and one end of each engages with each of the pair of left and right guide members. a pressurizing lever, a pressurizing bolt whose both ends are regulated in position at the other ends of the pair of pressurizing levers, and a pressurizing bolt screwed into a desired position of the pressurizing bolt in a reverse thread relationship. 1
a pressure member consisting of a pair of pressure plates, one end of each of which is fixed to each of the pair of pressure plates of the pressure member, the center of which is arranged parallel to the axis of the roll; By using a pressure mechanism that includes a pair of compression springs at the other end of each lever, it is possible to provide a lightweight, small and compact pressure fixing device. Since the adjustment can be made from both the Japanese and French V and J of the pressurizing bolts, the A section of the pressurizing force can be simplified.

[Brief explanation of the drawing]

Fig. 1 is a top view showing a conventional device IT, Fig. 2 is a side view of the same, and Fig. 3 is a front view showing another conventional device.
The drawings are side views, and Fig. W45 is a front view showing an embodiment of the present invention, and Fig. WJ6 is a side sectional view taken along the AAZ line in Fig. 5. 14-...lower roll, 18-...upper roll, 20-
... Skewer compression coil spring, 32 ... Frame, 341
1...Top roll, 39...Middle roll, 40...
・Lower OK, 42...disc spring, 51...-upper roll, 54...frame, 55...middle roll, 5
8... Lower roll, 61... Pressure lever, 63...
... Pressure coil spring, 64 ... Pressure bolt, 66
@...Natsuto.

Claims (1)

[Scope of Claims] (The axes of the 11 rolls are approximately in the same plane, the first roll is rotatably supported on a frame, and the other rolls are in a plane including the roll axis in the frame. Then, a pair of guide members, which are slidably provided in a direction perpendicular to the roll shaft edge, are supported by the internal member, and also press a pair of guide members which support another roll that is far from the first roll. , When a recording medium is passed through an arbitrary point between adjacent rolls, pressure is applied to the recording medium in 11 pressure chambers. A pair of pressure levers each having one end engaged with a corresponding one of the pair of forward-facing guide members; and one end of each of the pressure levers having #1 pair A pressure member consisting of 11 pressure bolts positioned at the other end and a pair of pressure plates screwed into the F9T desired position of the pressure bolts in a reverse thread relationship; a pair of compressors that are locked to each of the pair of pressure plates of the pressure member, the center of which is arranged parallel to the axis of the Ronil, and whose other end is the other end of each of the pair of pressure levers; It has a pressurizing mechanism equipped with a spring, and the pressurizing force can be adjusted by
A pressure fixing device characterized by being operated by the body. (2) The compression spring is a compression coil spring, and the other end of each of the pair of pressure levers is a pair of members screwed to the pressure bolt at a position opposite to the compression coil spring. The pressure fixing device according to the patent-requested range@paragraph (1), wherein the pressure fixing device contacts each of the parts and has a rotation range divided into black sections.