JP3698980B2 - Electromagnetic transmission device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission device in a micro electromagnetic braking device used for office automation equipment, particularly a copying machine.
[0002]
[Prior art]
FIG. 4 shows a transmission device in an electromagnetic braking device conventionally used. In the figure, 21 is a U-shaped yoke, 22 is a coil built in and fixed to the yoke 21 by a resin 23, and 24 is this coil 22. 25 is a lining fixed to the surface of the resin 23, 26 is an amateur provided on the side surface of the yoke 21 via a gap g, 26a is an outside of the amateur 26, and 26b is also an inside, A non-magnetic ring 27 is provided between them, and the thickness thereof is G, and the respective members are fixed and integrated.
[0003]
Further, the armature 26 is fixed by a spring 28 and a rivet 29. On the other hand, a hub 30 and a spring 28 fixed to a rotating shaft (not shown) are fixed to a rivet 31, and the armature 26 itself is supported by the spring 28 so as to move in the axial direction.
The inner and outer pole portions 21 a and 21 b of the opening of the yoke 21 form a friction surface that slides with the armature 26.
[0004]
FIG. 5 is a sectional view showing a conventional electromagnetic transmission device. In the figure, 32 is a U-shaped yoke, 33 is a bobbin fixedly press-fitted into the yoke 32, and 34 is a coil wound around the bobbin 33. , 35 is a stator, and 36 is an amateur provided through a gap g.
The stator 35 is provided with slits 35a for interrupting magnetic adhesion over several places on the entire circumference, and is fixed to the yoke 32 with screws 37 through gaps G.
Further, the inner and outer pole portions 35b and 35c of the stator 35 form a friction surface that slides with the armature 36.
4 and 5 both show a braking device, and the amateurs 26 and 36 show a case where they are in an open state.
[0005]
Next, the operation of the conventional apparatus configured as described above will be described.
When a voltage is applied from a power source (not shown) to the coils 22 and 34 via the lead wire 24, a magnetic flux Φ is generated in the magnetic path indicated by the dotted line, and the amateurs 26 and 36 overcome the elastic force of the spring 28 by the attractive force. Then, it is sucked by the stators 21 and 35. Therefore, the amateurs 26 and 36 slide on the inner and outer pole portions of the lining 25 or the stator 35 and stop the rotation shaft (not shown) via the spring 28 and the hub 30.
When the voltages of the coils 22 and 34 are removed, the magnetic flux Φ disappears, the amateurs 26 and 36 return to their original positions by the elastic force of the spring 28, and a gap g is formed between the amateurs 26 and 36 and the lining 25 or the stator 35. The amateurs 26 and 36 start rotating again.
[0006]
In the electromagnetic transmission device configured as described above, when used in a copying machine or the like, it must have stable performance and be manufactured at a low cost, and further, the responsiveness is required to operate extremely fast. Has been. That is, particularly when the voltage is removed, the amateurs 26 and 36 need to quickly leave the lining 25 and return to their original positions.
As a countermeasure, in FIG. 4, the armature 26 is divided into two parts and a ring 27 made of a nonmagnetic material is provided. As described above, when the non-magnetic part (gap part) is provided in a part of the magnetic circuit, the magnetic flux Φ disappears quickly and the armature 26 is separated from the lining 25.
[0007]
[Problems to be solved by the invention]
The conventional electromagnetic transmission apparatus is configured as described above. In the apparatus shown in FIG. 4, it is very expensive to manufacture the armature 26. In other words, the amateurs 26a and 26b and the ring 27 need to transmit torque, so it is necessary to increase the mechanical strength, and it is necessary to manufacture by relying on copper brazing or the like.
In the apparatus of FIG. 5, since the gap G is provided between the stator 35 and the yoke 32, the armature 36 does not need to be divided into two parts. However, for fixing the stator 35 and the yoke 32, a screw 37 is used. Because it is used, it was very expensive.
[0008]
Further, in the apparatus of FIG. 4, since the lining 25 is fixed to the resin 23, there is an advantage that it can be manufactured at low cost. However, frictional heat is generated when the lining 25 and the armature 26 are braked. This frictional heat raises the temperature of the entire apparatus as well as the lining 25 itself. However, the thermal expansion coefficient is different between the resin 23 and the iron material constituting the yoke 21, and the resin 23 is naturally larger.
[0009]
In spite of the fact that the inner and outer pole portions 21a, 21b sliding with the armature 26 and the lining 25 are formed on substantially the same surface, the resin 23 expands due to frictional heat during use, and the lining 25 is There is a problem in that the initial torque performance cannot be ensured by protruding from the inner and outer pole portions 21a and 21b. In order to suppress the frictional heat as a countermeasure, it is necessary to limit the specifications. For this reason, the function is limited and a problem in use may occur.
[0010]
The present invention has been made to solve the above-described problems, and an object thereof is to provide an electromagnetic transmission device having a stable function and capable of being manufactured at low cost.
[0011]
[Means for Solving the Problems]
An electromagnetic transmission device according to a first aspect of the present invention includes a yoke having a U-shaped cross section, a coil built in the yoke, a stator fixed to the opening of the yoke, and an opening of the yoke. The stator is an arm provided through a gap, and the stator is press-fitted and fixed to the outside of the yoke, and the inner side is provided through the gap in the radial direction.
[0012]
According to a second aspect of the present invention, the electromagnetic transmission device is provided with slits at several locations around the stator.
[0013]
According to a third aspect of the present invention, there is provided an electromagnetic transmission device having a U-shaped yoke, a bobbin which is built in the yoke and has a coil wound therein, and is fixed to an opening of the yoke. It consists of a stator, an armature provided through an opening of the yoke and a gap, and a spacer is provided on a part of the bobbin, and this spacer is sandwiched between the stator and the yoke. It is.
[0014]
The electromagnetic transmission device according to claim 4 of the present invention is configured such that slits are provided at several places on the entire circumference of the stator and the bobbin collar closes the slits.
[0015]
According to a fifth aspect of the present invention, there is provided an electromagnetic transmission device in which a lining is fixed to a stator.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 is a cross-sectional view showing an electromagnetic transmission device according to Embodiment 1 of the present invention. In the figure, 1 is a yoke, 2 is a coil wound around a bobbin 3, 4 is a stator, and 4a is for interrupting magnetism. A slit provided in the stator 4, a lining fixed to the stator 4, and a spacer 6 made of a nonmagnetic material for providing a gap H in a part of the magnetic circuit.
[0017]
Further, 1a is an outer pole portion forming a friction surface provided on the yoke 1, 4b is an inner pole portion similarly forming a friction surface provided on the stator 4, 7 is a lead wire connected to the coil 2, and 8 is The armature 8 is provided on the side surface of the yoke 1 via a gap g. The armature 8 is fixed by a spring 9 and a rivet 10. On the other hand, a hub 11 and a spring 9 fixed to a rotating shaft (not shown) are fixed by a rivet 12, and the armature 8 itself is supported by the spring 9 so as to move in the axial direction.
[0018]
According to the electromagnetic transmission device according to the first embodiment of the present invention configured as described above, the stator 4 is press-fitted into the U-shaped hole of the yoke 1 and fixed.
In other words, the outer peripheral side of the stator 4 is press-fitted into the inner periphery of the U-shaped outer side of the yoke 1. At this press-fitting, if a spacer 6 made of non-magnetic material is assembled and press-fitted into the contact surface of the yoke 1 beforehand. The gap H can be secured and the disappearance of the magnetic flux Φ can be accelerated at a low cost.
[0019]
When the stator 35 having the inner and outer pole portions shown in FIG. 5 is compared with the conventional technique in which the same is press-fitted into the yoke 32, the one shown in FIG. Since this is not possible, it becomes difficult to ensure the torque performance. In some cases, it is necessary to enlarge the coil 34 to increase the suction force.
As a result, the entire apparatus becomes large as an electromagnetic transmission device, which is disadvantageous as a product. From this point, it can be seen that the effect of the present invention is enormous.
[0020]
Furthermore, in the configuration shown in FIG. 1, it may be used without the lining 5 depending on use conditions. At this time, iron powder generated when the stator 4 and the armature 8 slip may enter the coil 2 from the slit 4a and cause insulation deterioration. However, according to the present invention, when the gap G is provided by the spacer 6, At the same time, because it is manufactured so as to cover the slit 4a, the iron powder is blocked here, does not enter the coil 2 side, and it is not necessary to fill the coil with resin as in the prior art shown in FIG. This enables inexpensive and reliable insulation.
[0021]
As described above, according to the electromagnetic transmission device of the present invention, the stator 4 is press-fitted into the yoke 1 and the spacer 6 made of a nonmagnetic material is sandwiched between the mating surfaces. Equipment can be produced.
Although the brake has been described in the present invention, it can be used as a clutch if the yoke 1 is rotated.
Furthermore, although it demonstrated for OA equipment in this invention, it cannot be overemphasized that it can apply also to a general industrial machine.
[0022]
Embodiment 2. FIG.
In the first embodiment, the example in which the gap is provided in the axial direction is shown. However, in this embodiment, the gap is provided in the radial direction.
2 is a cross-sectional view showing an electromagnetic transmission device according to Embodiment 2 of the present invention. In FIG. 2, 13 is a yoke, 14 is a stator, and they are press-fitted on the outside as shown in FIG. The inner side is configured to provide a gap I in the radial direction. 14a is a slit for magnetic shielding.
Note that the slit 14 a portion formed in the stator 14 is configured to be closed by the bobbin 3.
[0023]
According to the present embodiment, the gap I is provided in the radial direction, and further, the wear powder is prevented from entering the coil 2 side from the gap I or the slit 14a. Therefore, compared with the case of the first embodiment. Thus, the non-magnetic spacer can be eliminated, and it can be manufactured at a lower cost, and at the same time, stable performance can be obtained.
[0024]
Embodiment 3 FIG.
In this embodiment, a non-magnetic spacer is abolished using a bobbin material.
3 is a cross-sectional view showing an electromagnetic transmission device according to Embodiment 3 of the present invention. In the figure, reference numeral 15 denotes a bobbin having a coil 2 built therein, which is made of a resin material. Reference numeral 15 a denotes a spacer integrally formed with the bobbin 15, and 15 b denotes a flange of the bobbin 15, which is configured to close the slit 4 a of the stator 4.
[0025]
According to the present embodiment, since the spacer 15a is provided by using a part of the bobbin 15 made of resin, since it can be integrated by molding, the parts can be omitted, and therefore the assembly can be shortened. It can be manufactured at low cost. Further, since the spacer 15a is sandwiched between the stator 4 and the yoke 1, the bobbin 15 itself does not need to be press-fitted into the yoke 1, and assembly can be shortened.
Furthermore, the slit 4a can be closed using the flange 15b of the bobbin 15.
[0026]
【The invention's effect】
According to the electromagnetic transmission device of the first aspect of the present invention, the yoke having a U-shaped cross section, the coil built in the yoke, the stator fixed to the opening of the yoke, and the opening of the yoke The stator is press-fitted and fixed to the outside of the yoke and the inner side is provided via the gap in the radial direction, so that it can be manufactured at a low cost. Stable performance can be obtained.
[0027]
According to the electromagnetic transmission device according to the second aspect of the present invention, since the slits are provided in the whole circumference of the stator, the magnetism can be interrupted.
[0028]
According to the electromagnetic transmission device according to claim 3 of the present invention, a yoke having a U-shaped cross section, a bobbin built in the yoke and having a coil wound therein, and fixed to the opening of the yoke The stator is made up of the stator and the yoke opening and the armature provided through the air gap. A spacer is provided on a part of the bobbin, and the spacer is sandwiched between the stator and the yoke. Therefore, assembly can be performed easily.
[0029]
According to the electromagnetic transmission device according to claim 4 of the present invention, since the slits are provided in the whole circumference of the stator and the flange of the bobbin closes the slits, the magnetism can be interrupted and at the same time the iron powder is applied to the coil. Can be prevented from entering.
[0030]
According to the electromagnetic transmission device according to claim 5 of the present invention, since the lining is fixed to the stator, it can be produced at low cost.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an electromagnetic transmission device according to Embodiment 1 of the present invention.
FIG. 2 is a sectional view showing an electromagnetic transmission device according to a second embodiment of the present invention.
FIG. 3 is a sectional view showing an electromagnetic transmission device according to a third embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a conventional electromagnetic transmission device.
FIG. 5 is a cross-sectional view showing a conventional electromagnetic transmission device.
[Explanation of symbols]
1,13 yoke, 2 coils, 4,5,14 stator, 4a, 14a slit, 6 spacer, 8 amateur, 15 bobbin.

Claims (5)

A yoke having a U-shaped cross section, a coil built in the yoke, a stator fixed to the opening of the yoke, and an amateur provided through the opening of the yoke and a gap. In the electromagnetic transmission device, the stator is press-fitted and fixed to the outer side of the yoke, and the inner side is provided through a gap in the radial direction. The electromagnetic transmission device according to claim 1, wherein slits are provided in several places on the entire circumference of the stator. A yoke formed in a U-shape in cross section, a bobbin built in the yoke and having a coil wound therein, a stator fixed to the opening of the yoke, the opening of the yoke and a gap An electromagnetic transmission device comprising an amateur provided, wherein a spacer is provided on a part of the bobbin, and the spacer is sandwiched between the stator and a yoke. 4. The electromagnetic transmission device according to claim 3, wherein slits are provided at several places on the entire circumference of the stator, and bobbin ridges block the slits. The electromagnetic transmission device according to any one of claims 1 to 4, wherein a lining is fixed to the stator.

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