JPS63136953A - Eddy current braking equipment for vehicle - Google Patents

Abstract

PURPOSE:To eliminate the imbalance of attractive force on both sides of a disc, by detecting the flux density between the disc and the polar iron cores on both sides facing the disc surface and by controlling the output value to be equal. CONSTITUTION:The gap flux density between the polar iron cores 11A and 11B on both sides of a disc 8 and the surface facing the disc is detected by flux density detecting elements 14A and 14B such as Hall elements, search coils, etc. The voltage of the separate DC current flowing respectively to the exciting coils 12A and 12B on both sides of the disc is controlled so that the flux density value on both sides of the disc 8 outputted from these detecting elements 14A and 14B may always be equal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a disc-shaped eddy current brake device used, for example, in railway vehicles.

(Prior Art) A general example of a conventional disc-shaped eddy current brake device for an electric railway vehicle will be outlined with reference to FIGS. 5 to 8.

First, FIG. 5 is an explanatory diagram of a general electric vehicle, showing a state in which an M car 2 equipped with a main motor 1 and a T car 3 without the main motor 1 are connected.

Here, both the M car 2 and the T car 3 require a brake device, and in general, the M car 2 operates the main motor 1 as a generator when a vehicle braking command is issued, and the braking resistor 4 consumes energy. Get braking power. Further, the T vehicle 3 is provided with an eddy current brake device 5 by utilizing the space inside the truck, and is configured to be excited by a DC excitation power source 13.

As shown in FIGS. 6 to 8, the eddy current brake device 5 is fixed to an axle 7 that holds left and right wheels 6 so that a disc 8 rotates together with the axle 7, and a blade truck. A pair of frames 1 are fixed to the underframe 9 (see Figure 7).
0 are arranged facing each other at spaced apart positions on both sides of the disk 8,
A plurality of excitation coils 12 are wound on the opposing inner surfaces of the frame 10 on both sides at intervals in the circumferential direction of the disk 8, and a predetermined gap is formed between each pair on both sides of the disk 8. They are mounted facing each other through the

Therefore, each exciting coil 1 of the eddy current brake device 5
2 is connected to a DC excitation power supply circuit 13 shown in FIG. is generated to apply braking force to the axle 7, thereby braking the vehicle.

6 is a perspective view of the disc-type eddy current brake device, FIG. 7 is a side view with a part cut away, and FIG.
FIG. 3 is a cross-sectional view taken along line A-A in the figure.

(Problems to be Solved by the Invention) By the way, since the bogie frame 9 is supported by a spring (not shown) on the axle 7 via an axle box, it may be affected by problems such as when passing a curve while traveling or when the rail surface is uneven. Due to the movement of the vehicle, its position relative to the axle 7 changes.

Due to this variation, the gap between the disk 8 and the magnetic pole core 11 does not always have the same size on the left and right sides, and if it increases on one side, it decreases on the other side.

In addition, when the exciting coil 12 is excited while the vehicle is running, that is, when the eddy current brake 5 is operating, the magnetic pole core 11 is an electromagnet, so a large attractive force is exerted between it and the disk 8. . This attractive force changes the magnetic resistance of the magnetic circuit as the gap size changes, causing the magnetic flux density to change, resulting in a significant increase or decrease in the magnetic flux density.

These relationships are shown in FIGS. 9 and 10.

That is, FIG. 9 is an enlarged view of a part of FIG. 8 to explain when the left and right gaps are biased, and FIG. 10 is a diagram showing magnetic flux density and attractive force with respect to gap dimensions.

From this, for example, the dimension when the left and right gaps are equal is g.

Then, when there is no relative displacement between the truck frame 9 and the disk 8, the suction force is F on both the left and right sides. Therefore, there is a balanced state, and no particularly large force is applied to the bogie frame 9 and the like.

However, if we consider the case where the relative displacement is X, the right side where the gap has increased, that is, the gap dimension (g + x
), the suction force becomes Fl, and on the left side where the gear is reduced, the suction force becomes F2 at the gap size (go x).

Therefore, the force FIIIF1-F2 acts on the frame 10 of the eddy current brake and the truck underframe 9 with respect to the disk 8. When both the displacement fix and the excitation current are constant, this force F increases as the speed decreases as shown in Figure 11 (relationship diagram between attraction force and vehicle speed), and in extreme cases, the eddy current of one vehicle increases. 10 per brake device
It is known that the force can reach more than a ton.

Since this force is an attractive force, it is strongly pulled on the side where the gap is narrower (for example, the left side), and acts in a direction that further narrows the gap.

Therefore, the springs connecting the axle box and the bogie need to have enough rigidity to withstand this force, which not only worsens the ride comfort of the vehicle, but also increases the strength of the bogie underframe 9 and the frame 10 of the eddy current brake 5. This has disadvantages, such as the fact that it is difficult to make it smaller and lighter because it requires a significant increase in the size.

Here, the present invention overcomes the difficulties of the conventional device and promptly prevents a difference in suction force from occurring even when the disk and eddy current brake are displaced due to vehicle motion, thereby preventing the bogie frame and the eddy current brake from forming. The object of the present invention is to provide a single-use eddy current brake device that makes it possible to reduce the size and weight of a current brake frame and realize an axial spring that takes riding comfort into consideration.

[Structure of the invention]

(Means for Solving the Problems) The present invention fixes a disk integrally to the axle perpendicularly to the axle, and attaches magnetic pole cores to both sides of the disk near the outer periphery through a support frame supported by the bogie frame. A plurality of excitation coils are wound around the disk, and a plurality of them are arranged facing each other so as to sandwich the disk from both sides through a gap, and the magnetic field generated by excitation of these excitation coils generates eddy currents in the disk. In a disc-shaped single-use eddy current brake device that applies braking force to the axle, the left and right magnetic flux densities attached to the left and right magnetic pole cores are used to detect the gap magnetic flux density between the left and right magnetic pole cores of the disk and the surface facing the disk. It has a detection element, has a comparator that compares the detection outputs of both the left and right magnetic flux density detection elements, derives a deviation with either positive or negative polarity, and sends this deviation to the corresponding excitation coil. Positive to flow.

A converter is provided to convert the correction current to a negative polarity, and the left and right excitation coils reciprocally add to the basic excitation current applied to the left and right excitation coils according to the polarity of the correction current. This is a single-use eddy current brake device equipped with left and right DC excitation power supplies that respectively provide excitation current.

(Function) The present invention provides a disc type eddy current brake device that is provided with a magnetic flux density detection element such as a Hall element or a search coil that detects the gap magnetic flux density between the magnetic pole cores on both sides of the disc and the disc facing surface. so that the magnetic flux density values on both sides of the disk output from the element are always equal.
A larger excitation current is passed through the excitation coil on the side where the magnetic flux density is lower, that is, the gap between the pole iron core and the disk facing surface is larger, and a smaller excitation current is passed through the excitation coil on the side where the magnetic flux density is higher, that is, the gap between the pole iron core and the disk is smaller. Since the voltages of separate DC excitation currents connected to the excitation coils on both sides of the disk are controlled, even if the disk and the magnetic pole core are displaced due to vehicle motion and the left and right gaps change, the voltage at each gap is controlled. The magnetic flux density is detected by separate detection elements, and the magnetic flux density detection output signals from these two detection elements are input to a control device, and the control device ensures that the left and right gap magnetic flux densities from the two detection elements are always equal. The voltage of the DC excitation power supply is controlled, and as a result, despite the relative displacement of this eddy current brake device with the disk, the left and right suction forces remain constant, and the eddy current brake device has a constant attraction force on the undercarriage frame and the frame of the eddy current brake device. No large force is applied.

(Embodiment) FIG. 1 shows a side sectional view of the main parts around the disk in an embodiment of the present invention, and FIG. 2 shows a block diagram of the control circuit configuration thereof.

The same reference numerals represent the same parts in all drawings.

The disk 8 fixed to the axle 7 has magnetic pole cores 11A and 11B provided on both sides thereof, each having an excitation coil 12.
A and 12B are wound around the magnetic pole core 11A, which are arranged facing each other and are excited by the excitation coils 12A and 12B.
, IIB are provided on both sides with the disk 8 in between.

The detection probes 14A, 14B are made of, for example, Hall elements, and are embedded in the surfaces of the magnetic pole cores 11A, 11B facing the disk 8, which face the side surface of the disk 8 with a gap therebetween.

Hall elements 11B and Hall elements 14A and 14B are attached so that their respective surfaces are aligned.

Further, a control device 15 is provided as shown in FIG. 2 to control the DC excitation power supply voltage so that the gap magnetic flux densities on the right and left sides outputted from the detection elements 14A and 14B are always equal.

In FIG. 2, this control device 15 includes a detection element 14A,
14B output to buffer amplifier 16A.

16B and the difference in output +ΔB or -ΔB
is output from the comparator 17, and the difference numerator ΔB or -Δ
The basic excitation current ■ is output from the basic excitation current pattern circuit 19 via the converter 18 that calculates the correction current +ΔI or −ΔI corresponding to B. Add or subtract from.

The calculation is performed by the comparator 17 in the adders 2OA and 20B.
When the detection input to the converter 18 has the sign shown in the figure, the input sign when adding ±Δl to the adders 2OA and 20B is also as shown in the figure. For example, when the output of the converter 18 is +ΔI, it is added as is. However, when it is -ΔI, the input to the adder 2OA is -Δl, and the input to the adder 20B is +Δ■.

Therefore, in the case of Fig. 2, the current command value (I + ΔI) and (Io - ΔI
) manually. Thereby, it is configured to output voltages E and E2 for exciting the right and left side coils 12A and 12B of the eddy current brake device.

Next, the operation of this embodiment will be described.

The eddy current brake 5 is in operation, i.e. the excitation coil 12
In a state where equal current is applied to A and 12B, due to vehicle movement, the gap size between the disk 8 and the magnetic pole core 11A becomes (go + x) as shown in FIG.
Consider a case where the gap size between the disk 8 and the magnetic pole core 11B narrows to (g□-x).

At this time, the magnetic resistance of the gap on the left side of the disk 8 shown in FIG. 9 decreases and the magnetic flux density increases, and conversely, the magnetic resistance of the gap on the right side increases, so the magnetic flux density decreases. Then, as shown in FIG. 1, the outputs of the Hall elements 14A and 14B attached to the magnetic pole surface are such that the Hall element 14A outputs a small value B2, and the Hall element 14B outputs a large value B1.

The outputs of these two detection elements are input to the control device 15, input to buffer amplifiers 16A and 16B, respectively, and their outputs are input to the comparator 17.

This comparator outputs ±ΔB-81-82. This output value of ±ΔB is input to the converter 18, which outputs an instruction value of the corrected current value ±Δ1 corresponding to ±ΔB.

The indicated value of this correction current ±ΔI is determined by the DC excitation power supply voltage control circuits 21A and 2 that excite the right side excitation coil 12A and left side excitation coil 12B of the eddy current brake 5, respectively.
This is the correction instruction value for 1B.

That is, the basic excitation current I output from the basic excitation current pattern circuit 19. In contrast, the adder 2OA outputs an instruction value of (Io + Δ■) to the excitation coil 21A for the right side, and the instruction value of (io - ΔI) is output from the adder 20B to the excitation coil 21B for the left side. As a result, the excitation current of the right excitation coil 12A increases and the right gap magnetic flux density increases, and conversely, the excitation current of the left excitation coil 12B decreases and the left gap magnetic flux density decreases.
The left and right gap magnetic flux densities can be made equal,
With this, the left and right excitation coils 12B.

The attraction force of 12A to the disk 8 becomes the same value.

In this way, even if the dimensions of the left and right gaps sandwiching the disc 8 of the eddy current brake change due to vehicle motion, the attraction forces of the left and right excitation coils 12B and 12A to the disc 8 can be made equal, so the eddy current brake frame 10A, I
Since the unbalanced force due to the unbalanced suction force described above does not work on the OB and the bogie underframe 9, it is possible to make settings that are more compact in terms of strength.
0A, IOB can be made smaller and lighter.

In addition, the axle springs that support the axle box and bogie underframe, which had to be strong enough to withstand unbalanced suction force and had poor riding comfort, can now be set to the optimal spring constants that take into account riding comfort. The vehicle as a whole has a comfortable ride.

Next, FIG. 3 shows a partial side sectional view of another embodiment of the present invention. In other embodiments, magnetic flux density detection elements 14A, 1
4B to magnetic pole core 11A, IIB frame IOA, IO
It is arranged on the joint surface to B.

Furthermore, FIG. 4 is a side sectional view of a main part of another embodiment of the present invention. This other embodiment includes search coils 22A and 22B as magnetic flux density detection elements.

That is, although Hall elements were used as the gap magnetic flux density detection elements 14A and 14B in the above embodiment, for example, as shown in FIG. A detection element may be placed at a location where a magnetic flux density that is approximately proportional to the magnetic flux density occurs, and the search coils 22A and 22B are wound around the magnetic pole iron cores 11A and IIB as the detection elements.
The same effect as described above can be obtained by applying a small current to this and calculating the magnetic flux density based on the relationship between the voltage and the current.

〔Effect of the invention〕

Thus, according to the present invention, the magnetic flux density between the magnetic pole cores on both the left and right sides of the disk facing surface of the single-use eddy current brake device and the disk is detected by the detection element, and the output values are controlled so that they are the same. To eliminate the unbalance of the suction force between the left and right sides of the disc, thereby preventing large forces from being applied to the eddy current brake device frame and the bogie underframe, thereby achieving a reduction in size and weight of the eddy current brake and the bogie underframe. I can do it.

Furthermore, the axle spring that connects the axle box and the bogie frame, which had to have a force that can withstand unbalanced suction force, can be configured with comfort in mind, so the ride comfort of the vehicle can be significantly improved.

As described above, the present invention has significantly superior effects compared to conventional devices.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of the main part of one embodiment of the present invention, FIG. 2 is a block diagram showing the enclosure configuration of the control system, and FIGS. 3 and 4 are other and different embodiments of the present invention. A side sectional view of a part of the embodiment, FIG. 5 is an explanatory diagram of a general electric railway vehicle, FIG. 6 is a perspective view showing a conventional example of an eddy current brake device, and FIG. 7 is a partially cutaway view. A side view, Fig. 8 is a cross-sectional view taken along line A-A in Fig. 7, Fig. 9 is an enlarged view of a part of Fig. 8 and is an explanatory diagram when the left and right gaps are biased, Fig. 10 is a gap FIG. 11 is a diagram showing the relationship between the magnetic flux density and the attractive force with respect to the dimensions, and FIG. 11 is a diagram showing the relationship between the attractive force and the vehicle speed. 1... Main motor 2... M car 3... T car 4... Braking resistance 5... Eddy current brake device 6... ... Wheel 7 ... Axle 8 ... Disk 9 ... Bogie frame 10, IOA, 10B ... Frame 11,
IIA, IIB...Magnetic pole iron core 12.12A, 1
2B... Excitation coil 13... DC excitation power supply 14A, 14B... Magnetic flux density detection element (for example, Hall element) 15... Control device 16A, 16B. ...Buffer amplifier 17...
... Comparator 18 ... Converter 19 ... Basic excitation current pattern circuit 2OA, 2
0B...Adder 21A, 21B...DC excitation power supply (voltage control circuit) 22A, 22B...Magnetic flux density detection element (for example, search coil). Applicant's Representative Sato - Shiima 1 Figure b Figure 2 Figure 5 Figure 7 Figure 10 Figure 11

Claims (1)

[Claims] 1. The disk is integrally fixed to the axle perpendicularly to the axle, and magnetic pole iron cores and excitation coils wound around the disks are attached to both sides of the disk through a support frame supported by the bogie frame, respectively. A plurality of these discs are arranged facing each other with a gap between them from both sides, and the magnetic field generated by exciting these excitation coils generates eddy currents in the discs and applies braking force to the axle. In a disc-shaped eddy current brake device for a vehicle, left and right magnetic flux density detection elements attached to the left and right magnetic pole cores that detect the gap magnetic flux density between the left and right magnetic pole cores of the disk and the disk facing surface; A comparator that compares the detection outputs of both magnetic flux density detection elements on the right side and derives a deviation with either positive or negative polarity, and a comparator that derives a deviation with either positive or negative polarity to flow this deviation to the corresponding excitation coil. According to the polarity of the correction current, the left and right excitation coils add the basic excitation current to the left and right excitation coils reciprocally to give the excitation current respectively. A dual-use eddy current brake device characterized by being equipped with left and right DC excitation power supplies. 2. The eddy current brake device for a vehicle according to claim 1, wherein the magnetic flux density detection element is a Hall element provided at a part of the magnetic pole core or at a location where magnetic flux density is generated in proportion thereto. 3. The magnetic flux density detection element is a search coil that is wound around a part of the magnetic pole core or a location where magnetic flux density is generated in proportion to it, passes a minute current, and determines the gap magnetic flux density from the relationship between the voltage and current. An eddy current brake device for a vehicle according to claim 1.