JPH02159435A - Electromagnet-operated spring - Google Patents

Abstract

PURPOSE:To perform fixing and releasing of a printing sheet while fixing pressure is kept constant by providing a second electromagnet on the side of a sheet fixing device on the opposite side from a first electromagnet provided on the side of a rotary roller, and switching polarity direction of the second electromagnet to positive or negative relative to the first electromagnet. CONSTITUTION:An electromagnet 4 is provided on the side of a rotary roller 1, and an electromagnet 5 is provided through a column 3 on opposite side of the electromagnet 4 on the side of a printing sheet fixing device 2 for pressing a printing sheet against the roller 1. Both electromagnets 4, 5 are then energized by DC power supply 7, and polarity of the electromagnet 5 is switched relative to the electromagnet 4 by an interlocking switch 6. Fixing ans releasing of the printing sheet can thus be performed by the interlocking switch 6, and pressure for fixing the printing sheet can be kept constant.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an electromagnetic spring, and particularly to an electromagnetic spring that uses the attractive and repulsive forces of an electromagnet to operate a paper fixing device that presses printing paper against a rotating roller in a printer or the like. Regarding.

[Conventional technology]

Conventionally, as shown in FIG. 2, this type of printing paper fixing device uses a metal spring 13, and utilizes its elasticity and tension to fix and fix the printing paper by the fixing device 12 to the rotating roller 11. The fixing and unfixing operations must be done manually, and metal fatigue of the spring 13 makes it impossible to maintain a constant fixing pressure on the printing paper.

[Problem to be solved by the invention]

Since the metal spring in the conventional fixator described above uses the elasticity and tension of the material, it has the drawback of causing damage, failure, or reduction in elasticity and tension due to metal fatigue.

The present invention eliminates the above-mentioned conventional drawbacks and provides an electromagnetic spring that has a spring function by utilizing the polarity change of the electromagnet.

[Means to solve the problem]

The electromagnetic spring of the present invention includes a rotating roller, a paper fixing device for pressing the printing paper against the rotating roller, a first electromagnet provided on the rotating roller side, and a first electromagnet provided on the paper fixing device side and a second electromagnet disposed to face the first electromagnet; a DC power supply and power switch that excites the first and second electromagnets; and a second electromagnet in the polarity direction of the first electromagnet. It is equipped with a changeover switch that switches the polarity direction of the polarity between forward and reverse.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

The first example is a configuration diagram including a partial cross section of an embodiment of the present invention.

This embodiment includes a rotating roller 1, a printing paper fixing device 2 for pressing the printing paper against the rotating roller 1, an electromagnet 4 provided on the rotating roller 1 side, and a printing paper fixing device 2.
An electromagnet 5 provided on the side and arranged to face the electromagnet 4 via the cylinder 3, a DC power source 7 and a power switch 8 for supplying power to and exciting the electromagnet 4.5, and a polarity direction of the electromagnet 4. The electromagnet 5 is provided with an interlocking switch 6 for switching the polarity direction of the electromagnet 5 between forward and reverse directions. Here, the electromagnet 4 is a base electromagnet, and the electromagnet 5 is an electromagnet whose polarity changes by switching an interlocking switch 6. Note that the power switch 8 is the power switch of the printer device or facsimile device itself.

Next, the operation of this embodiment having such a configuration will be explained.

When the power switch 8 is turned on, a direct current flows through the electromagnets 4 and 5. Since current always flows in the same direction in the electromagnet 4, the magnetic material inside the cylinder 3 generated by the electromagnet 4 maintains a constant polarity (if a north pole occurs, it always turns into a north pole,
If an S pole occurs, it is always an S pole). When the interlocking switch 6 is off, the electromagnet 5 receives the same magnetic field as the electromagnet 4 from the cylinder 3.
They are generated in the magnetic material of the electromagnet 5 inside, and are made to repel each other. As a result, when the interlocking switch 6 is off, the rotating roller 1 and the print paper fixing device 2 are separated, and the fixation is released. When the interlocking switch 6 is turned on, the electromagnet 5
A current flows in the opposite direction, and the magnetic bodies inside the cylinder 3 generated by the electromagnet 5 have completely opposite polarities, and the polarities inside the cylinder 3 are different and attract each other. That is, by attracting each other, the printing paper fixing device 2 is moved against the rotating roller 1.
is pressed and becomes fixed.

In this way, in this embodiment, two electromagnets 4.5 are provided with the polarity generating portions facing each other, and the polarity of the electromagnet 4 serving as the base is not changed, but the direction of the current is changed by switching the interlocking switch 6. The electromagnets 5, whose polarity changes, generate forces that repel or attract each other depending on their polarities, and this force is used to function as a spring.

〔Effect of the invention〕

As explained above, by providing two electromagnets facing each other, one of which has variable polarity, the printing paper can be fixed and unfixed simply by turning on and off a switch. At the fixing pressure, elasticity due to metal fatigue is lower than that of metal springs.
Since no drop in tension occurs, the effect is that the pressure can always be kept constant.

[Brief explanation of the drawing]

FIG. 1 is a block diagram including a partial cross section of an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of a conventional printing paper fixer including a metal spring and a rotating roller. 1.11...Rotating roller, 2,12...Print paper fixer, 3...Cylinder, 4.5...Electromagnet, 6...
・Interlocking switch, 7...DC power supply, 8...Power switch, 13...Spring, 14...Fixing stand, 15
···Axis of rotation.

Claims (1)

[Claims] a rotating roller, a paper fixing device for pressing the printing paper against the rotating roller, a first electromagnet provided on the rotating roller side, and a paper fixing device provided on the paper fixing device side and facing the first electromagnet. a second electromagnet arranged as shown in FIG. An electromagnetic spring characterized by comprising a changeover switch.