JPH08728U - Eddy current retarder - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to increase the braking torque per weight of the retarder. [Structure] On the inner peripheral surface of the peripheral wall portion 20 of the hollow cylindrical body, facing the pole 22 formed so as to be long in the axial direction, and having the same width length shape as the axial length of the pole 22 and having a large electric conductivity. A metal layer 24 made of a material is provided, the hollow cylinder and the main shaft 19 are concentrically separated from each other, and the bottom wall 2 is provided at the opening end of the peripheral wall 20.
1 is integrally provided, the bottom wall portion 21 is fixed to the main shaft 19, and the peripheral wall portion 20 and the bottom wall portion 21 are configured to rotate integrally with the main shaft 19.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an eddy current retarder mounted on a vehicle as a braking assist device.

[0002]

[Prior art]

 The eddy current retarder is provided with a rotating body made of a ferromagnetic material and a magnet so that the rotating body cuts off a magnetic flux, and generates a braking force by an eddy current generated in the rotating body. It is a thing. One example of the eddy current retarder in the conventional example will be described with reference to FIG. In the figure, reference numerals 1 and 2 are flange couplings that are connected to the rotating shaft of the vehicle, and the flange couplings 1 and 2 and the main shaft 3 that is mounted so as not to rotate with each other rotate together with the rotating shaft of the vehicle. Disks 4 and 5 are mounted on the main shaft 3 so as not to rotate relative to each other. The coil 6 forms a pair with the pole 7 to form an electromagnet, and a plurality of the coils 6 and the poles 7 are arranged radially. The frame 9 connects the plurality of coils 6 and the poles 7 in a star shape. It is mounted so as to be able to rotate with each other. The frame 9 is fixed to the vehicle base so that it cannot rotate.

[0003]

[Problems to be solved by the device]

 In the conventional eddy current retarder, the weight of the eddy current retarder per generated braking torque is larger than that of other types of retarders, and the mounting position of the eddy current retarder on the vehicle is limited. I have. That is, if the electric resistance of the material of the rotating body in the eddy current retarder is small, a larger braking torque is generated under the same conditions, that is, if the coil size, the current, and the size of the gap between the pole and the rotating body are the same. However, since the material of the rotating body needs to be a magnetic material, there is no difference in the electric resistance value which causes a remarkable difference in the generated torque, whichever material is selected. Therefore, no matter which material is used for the rotating body, a large braking torque cannot be obtained as compared with the retarder of other methods.

[0004]

[Means for Solving the Problems]

 Means for solving the above problems will be described below with reference to FIG. 5 corresponding to the embodiment. This invention confronts the pole 22 formed in the axial direction on the inner peripheral surface of the peripheral wall portion 20 of the hollow cylindrical body, and has the same electrical conductivity as the axial length of the pole 22. A metal layer 24 made of a large material, the hollow cylinder and the main shaft 19 are concentrically separated from each other, the bottom wall 21 is integrally provided at the open end of the peripheral wall 20, and the bottom wall 21 is attached to the main shaft 19. The peripheral wall portion 20 and the bottom wall portion 21 are fixed so as to rotate integrally with the main shaft 19.

[0005]

[Action]

 In such a structure, the hollow cylindrical body, which is the rotating body, faces the pole 22 of the magnet through the metal layer 24, so that the eddy current generated in the rotating body increases and the braking torque increases.

[0006]

【Example】

 This invention will be described in detail with reference to the illustrated embodiment. FIG. 2 is a vertical cross-sectional explanatory view of an eddy current retarder in which a rotating body is formed of a disc. In FIG. 2, the flange couplings 1 and 2, the main shaft 3, the disks 4 and 5, the coil 6, the pole 7, the bearing 8 and the frame 9 are the same as the eddy current retarder in the conventional example. The metal layer 10 is provided on the surface of the disks 4, 5 facing the pole 7. That is, the outer diameter has the same diameter as the discs 4 and 5, and the inner diameter has the same diameter as the inner diameter of the pole 7 in the assembled state. Screw to form. The metal layer 10 may be formed by plating or welding.

FIG. 3 is an explanatory view showing the positional relationship between the disk 11 and the magnet, in which the rotating body is formed by one disk 11. In this embodiment, the magnet is arranged only on one side of the disk 11 and is formed by a U-shaped pole 12 and a coil 13. Even in this case, the metal layer 14 is formed in a thin ring shape on the facing surface of the pole 12 of the disk 11.

FIG. 4 is an explanatory diagram showing another embodiment. In this embodiment, the rotating body is formed of one disk 15, and the magnet forms the pole 16 in a so-called horseshoe shape, and the coil 17 is arranged so as to face both side surfaces of the outer peripheral portion of the disk 15. It is provided and formed. Even in this case, the metal layer 18 is formed in a thin ring shape, and is formed by being provided on the facing surface of the disk 15 and the pole 16, that is, on both surfaces of the outer peripheral portion of the disk 15.

FIG. 5 shows a rotary body formed of a hollow cylindrical body. That is, the rotating body is formed concentrically with the main shaft 19 so as to be long, and the bottom wall part 21 is integrally provided at one open end of the peripheral wall part 20 and the peripheral wall part 20, and the bottom wall part 21 is fixed to the main shaft 19. However, the peripheral wall portion 20 and the bottom wall portion 21 are configured to rotate integrally with the main shaft 19. Further, the pole 22 is formed to be long in the axial direction so as to face the inner peripheral surface of the peripheral wall portion 20 with a gap therebetween, and the pole 22 is axially wound around the side surface in the axial direction to provide a coil 23 to form a magnet. The magnets are arranged radially around the main shaft 19. It is intended to provide an eddy current retarder that is lightweight and has a large braking torque. That is, the poles 22 are provided by dividing one or a plurality of pieces on the same radial line centering on the main shaft 19, and winding the coil 23 around the pole 22. In this case, the metal layer 24 is formed on the inner peripheral surface of the peripheral wall portion 20 at a portion facing the pole 22. That is, a thin hollow cylindrical metal layer 24 having the same width as the axial length of the pole 22 is formed on the inner peripheral surface of the peripheral wall portion 20.

FIG. 6 shows another embodiment in which the rotating body is formed of a hollow cylindrical body. In the embodiment shown in FIG. 6, a pole 25 elongated in the axial direction and a magnet having a coil 26 wound around the side surface in the circumferential direction of the pole 25 in the axial direction are provided on the outer side of the peripheral wall portion 28 with the main shaft 19 as the center. Are arranged in a radial pattern. In this case, the metal layer 29 is formed on the outer peripheral surface of the peripheral wall portion 28 at a portion facing the pole 25. That is, a thin hollow cylindrical metal layer 29 is formed on the outer peripheral surface of the peripheral wall portion 28.

The operation of the metal layer is based on the braking torque-rotation number diagram for the embodiment shown in FIG. 3 in which the rotating body is formed of a disk and the metal layer is formed only on one surface of the disk. explain. Fig. 7 shows the case where the other dimensions are all the same, and the result shown in I shows the conventional example in which the gap is formed to 1 mm without providing the metal layer, and the result shown in II shows the result with the copper plate. A 1 mm metal layer is formed, and the gap between the metal layer and the pole is 1 mm. The results shown in I and II are measured at a current of 8 A and 60 seconds after the passage of electricity. It is confirmed that the generated torque increases by about 1.3 kilograms at a spindle speed of 1000 rpm.

[0012]

[Effect of device]

 According to this invention, since the rotating body faces the pole of the magnet through the metal layer, the eddy current generated in the rotating body increases and the braking torque can be increased. Therefore, the braking torque per weight of the retarder can be increased. Since the same braking torque can be made light and small, it is possible to provide an eddy current retarder that is easy to install on a vehicle and has a great benefit.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view of an eddy current retarder showing a conventional example.

FIG. 2 is a sectional explanatory view showing a first embodiment of the present invention.

FIG. 3 is an explanatory view showing a second embodiment of the present invention.

FIG. 4 is an explanatory view showing a third embodiment of the present invention.

FIG. 5 is an explanatory view showing a fourth embodiment of the present invention.

FIG. 6 is an explanatory view showing a fifth embodiment of the present invention.

FIG. 7 is a torque-rotational speed comparison diagram.

[Explanation of symbols]

 19 main shaft 20 peripheral wall 21 bottom wall 22 pole 24 metal layer

Claims (1)

[Scope of utility model registration request] 1. An eddy current retarder in which a rotating body made of a ferromagnetic material and a magnet are provided so that the rotating body cuts off a magnetic flux, and a braking force is generated by an eddy current generated in the rotating body. Provided on the inner peripheral surface of the peripheral wall portion is a metal layer formed of a material having high electrical conductivity, which has a width and a shape that are the same as the axial length of the pole, facing the pole that is long in the axial direction. The hollow cylindrical body and the main shaft are concentrically separated from each other, a bottom wall portion is integrally provided at an opening end of the peripheral wall portion, the bottom wall portion is fixed to the main shaft, and the peripheral wall portion and the bottom wall portion are the main shaft. Eddy current retarder characterized by being configured to rotate integrally with