JP3446546B2 - Double eddy current reduction gear - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reduction gear installed in a motor vehicle, and doubles a braking force (deceleration force) as compared with a conventional single type reduction gear. The present invention relates to an eddy current type speed reducer. 2. Description of the Related Art In addition to a foot brake serving as a main brake and an exhaust brake serving as an auxiliary brake, a braking device for a vehicle performs stable deceleration on a downhill on a long slope and burns the foot brake. An eddy current type speed reducer (hereinafter, referred to as a "retarder") is used to prevent the above problem. This retarder includes one using an electromagnet as a magnet and one using a permanent magnet. As disclosed in Japanese Patent Application Laid-Open No. 50-61574, for example, a retarder using an electromagnet is constituted by an electromagnet formed by winding a conductive wire around an iron core, and many of the electrodes are opposed to both surfaces of a disk. It is configured to be arranged. The deceleration force can be obtained by generating a magnetic field by energizing from a battery power source and generating a desired torque in a direction to decelerate the disk by eddy current generated in the disk. However, since this retarder uses an electromagnet in which a conductive wire is wound around an iron core as a magnetic pole, its weight and outer diameter become large. It is not preferable as equipment. In addition, power must be supplied during deceleration, and the battery power and the capacity of the generator must be increased since the power consumption of the battery is drastic. Therefore, the weight is further increased. In order to solve the above-mentioned problem, the present applicant uses permanent magnets instead of electromagnets, and changes the positions of the permanent magnets and the cylindrical portion of the rotor to generate eddy current in the cylindrical portion. A retarder for deceleration (JP-A 1-234043, JP-A 1-234045, JP-A 1-298948) has been proposed. FIG. 5 is a diagram showing an example of a retarder using a permanent magnet. FIG. 5A is a plan view seen from the direction of a rotation axis.
(b) is a sectional view taken along the line AA of (a). As shown in the figure, the retarder includes a rotor R fixed to the rotating shaft 1 and a stator S fixed to the transmission case 14. The rotor R has a cylindrical portion 5 having one end (the left side in the figure) joined to the tip of the spoke 4 and a bracket 2 attached to the end of the rotating shaft 1 via a disk 3 with a nut 13. Attached by bolt B1. A plurality of fins 6 for dissipating heat generated by eddy current are attached to an outer peripheral portion of the cylindrical portion 5. Further, the spoke has a structure in which a shock absorbing mechanism 4-1 made of a spring or the like is incorporated in a center portion, and can absorb deformation due to a temperature rise. The stator S is a case 1 for accommodating two ring-shaped yokes 8, 8-1 in which permanent magnets 7, 7-1 are fixed to the outer periphery.
0, and a case cover 11 provided with a pole piece 9 disposed at a position facing the outer peripheral portion of the permanent magnet. The case cover 11 is attached to a transmission case 14 via a case support 12 by bolts B2 and B3. FIGS. 6A and 6B are diagrams schematically showing the arrangement of the permanent magnets. FIG. 6A is a diagram showing a brake-off state, and FIG. 6B is a diagram showing a brake-on state. The permanent magnets 7, 7-1 are strip-shaped as shown in the figure, and are arranged at equal intervals around the outer periphery of the ring-shaped yokes 8, 8-1 with different polarities of the circumferentially adjacent surfaces. It is fixed to. The yoke 8 can be swung in the circumferential direction by a driving device (not shown) as indicated by the double-headed arrows, and the yoke 8-1 is fixed to the case 10 (see FIG. 5). Then, as shown in FIG. 6A, when the magnetic poles on the surfaces of the permanent magnet 7 and the permanent magnet 7-1 are arranged differently in the axial direction, the braking force does not act on the rotor.
As shown in FIG. 6 (b), when the arrangement is the same in the axial direction, a braking force acts on the rotor. In the braking-on state, the cylindrical portion of the rotor rotates as shown by a single arrow in FIG. 5 (a) across the magnetic field generated by the permanent magnet. A braking torque is generated in the rotor by the interaction between the eddy current and the magnetic field. The temperature of the cylindrical portion 5 is increased by Joule heat due to the eddy current, and is cooled and cooled by the cooling fins 6 in a brake-off state. [0012] In recent years, the braking ability required of the retarder has been increasing more and more. However, as described above, the transmission space is limited because the installation space and the body weight of the automobile are restricted. There is only one retarder in the case. The retarding force of the retarder can be increased by increasing the number of turns of the coil and increasing the current in the electromagnet type retarder. However, as described above, there is a disadvantage in that the weight increases due to the coil and the battery capacity increases. In the case of the permanent magnet type retarder, the magnetic force of the permanent magnet may be increased, or the radius of the rotating cylindrical portion or the permanent magnet may be increased, or the length in the rotation axis direction may be increased. In addition, since the cylindrical portion has a structure in which one end is fixed by the spokes as described above, one end has no restriction in the radial direction and is deformed due to an increase in temperature due to eddy current.
Therefore, when the body length of the cylindrical portion is increased, the amount of deformation is increased, and rotation is hindered. An object of the present invention is to provide a double permanent magnet type retarder which is installed in a part of a transmission case as in the prior art and can double the deceleration force. [0015] In order to achieve the above object, the present inventors conducted research on a method of compactly mounting an additional second stator, and supported the connecting plate and a flanged shaft neck. By doing so, it was confirmed that the mounting was stable, and the present invention was completed. The gist of the present invention resides in the following double retarder shown in FIG. A first cylindrical portion 5 having one end fixed to the first spoke 4 and one end being formed by the second spoke 4a
A rotor Ra having a fixed second cylindrical portion 5a ;
Spoke 4 and second spoke 4a are connected via disc 3
A first stator S and a second stator S comprising a bracket 2 to be mounted, yokes 8, 8a having permanent magnets 7, 7a inside respective cylindrical portions, and pole pieces 9, 9a.
a) a compound eddy current type speed reducer comprising :
Spokes 4 and second spokes 4a are arranged alternately,
The first cylindrical portion 5 and the second cylindrical portion 5a are the first spokes 4
And one back to back around the second spoke 4a
A double eddy current type reduction gear, which is attached to a bracket 2 . DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is characterized by a mounting structure of a second cylindrical portion and a second stator, and the structure will be described with reference to the drawings. FIG. 1 is a partial cross-sectional view showing an example of the compound retarder of the present invention. The compound retarder of the present invention comprises a rotor Ra having a first cylindrical portion 5 and a second cylindrical portion 5a in the axial direction, and a yoke in which permanent magnets 7, 7a are fixed inside each cylindrical portion. 8,8a
And a first stator S and a second stator Sa. Hereinafter, the retarder of the present invention is referred to as a rotor Ra,
The order of the second stator Sa and the first stator S will be described. FIGS. 2A and 2B are views showing a rotor of the retarder of the present invention, wherein FIG. 2A is a longitudinal sectional view, and FIG. The rotor Ra has a first cylindrical portion 5 and a second cylindrical portion 5a attached to a disk 3 by first spokes 4 and second spokes 4a, and a rotating shaft by a bolt B1 via a bracket 2. Attached to one. 2
The two cylindrical portions 5, 5a are joined in a cantilever shape such that one end of each is concentric with the upper end of the spoke 4, 4a about the rotation axis 1, and is symmetrical in the axial direction about the spoke. The lower end of the spoke is joined to the outer periphery of the disk 3. The cylindrical portion, spokes, disk, and bracket have the same structure as those of the conventional retarder shown in FIG. The bracket 2 has a nut 1
3, and a shaft neck 17 into which the bearing 16 is inserted is attached by a bolt B4 via a flange 17a. The shaft neck 17 has a screw at the end and a bearing with a chrysanthemum nut 18.
Sixteen inner rings are fixed and connected to a case support 12a of a second stator Sa described later. It is desirable that the shaft neck be a hollow shaft for weight reduction. In the rotor of the present invention, since two cylindrical portions are attached to one bracket back to back with the spokes as the center, the two cylindrical portions can be installed in a relatively small space. In addition, since the flanged shaft neck is attached to the bracket, the second stator can be fixed. FIG. 3 is a longitudinal sectional view showing an apparatus for accommodating the second stator. In this figure, a section of the shaft neck 17 shown in FIG. 2 is shown by a broken line. The present invention is characterized in an apparatus for supporting a second case 10a for accommodating a second stator Sa, and the structure of a stator including a permanent magnet and a yoke is equal to that of a conventional retarder. The second case 10a has an outer peripheral surface connected to the connecting plate 15 by bolts B4, and an inner peripheral portion connected to the second case support 12a by bolts B5. The connecting plate 15 is connected to an outer peripheral portion of a first case 10, which will be described later, and is connected to the transmission case via the first case. The second case support 12a has a bearing 16 and an oil seal 19 built in the center thereof, and is supported by a shaft neck 17 shown in FIG. 2 so as not to rotate. The bearing 16 has an outer ring fixed to the center of the case support 12a by a lid 20. That is, the second stator Sa is flexibly connected in the radial direction to the transmission case 14 by the connection plate 15 and is supported by the shaft neck 17 so as not to rotate substantially concentrically with the rotor 1. Even if the cylindrical portion rotates eccentrically, it follows this, and does not hinder the rotation of the rotor. FIGS. 4A and 4B are views showing the first stator mounted on the transmission case side, wherein FIG. 4A is a plan view and FIG. 4B is a longitudinal sectional view. Stator S shown in this figure
Is substantially the same as the stator of the conventional retarder shown in FIG. DESCRIPTION OF THE PREFERRED EMBODIMENTS Among the single retarders conventionally used, the braking torque is 196 Newton meter (hereinafter referred to as "(Nm)") and 490 (Nm) and the outside of the rotor. The double retarder of the present invention was manufactured with the same diameter, and the performance was compared with a single retarder conventionally used. Table 1 shows the main dimensions of the device and the braking torque obtained at a rotation speed of 2000 rpm. [Table 1] As shown in Table 1, the double retarder of the present invention has twice the braking torque for both braking torques, while having less than twice the width and weight of the single retarder. According to the double retarder of the present invention, two cylindrical portions for generating a braking force are assembled back to back, and the second stator is supported by the shaft and neck attached to the rotating shaft.
It is possible to obtain twice the braking force without doubling the installation space and weight as compared with the conventional retarder.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional view showing an example of a compound retarder according to the present invention. FIG. 2 is a view showing a rotor of the retarder of the present invention;
(a) is a longitudinal cross-sectional view, and (b) is a plan view as viewed from a rotation axis direction. FIG. 3 is a longitudinal sectional view showing a device for accommodating a second stator. FIG. 4 shows a first case attached to the transmission case side.
2A is a plan view, and FIG. 2B is a longitudinal sectional view. 5A and 5B are diagrams illustrating an example of a retarder using a permanent magnet, wherein FIG. 5A is a plan view as viewed from the rotation axis direction, and FIG.
FIG. FIG. 6 is a diagram schematically showing an arrangement of permanent magnets, and FIG.
FIG. 4 is a diagram illustrating a state where braking is off, and FIG. [Brief Description of Codes] Rotation axis 2. Bracket 3. Disk 4, 4a. Spoke 5,5a. Cylindrical part 6. Fins 7,7-1,7a, 7a-1. Permanent magnet 8,8-1,8a, 8A-1. Yoke9. Pole peace 10,10a. Case 11, 11a. Case cover 12,12a. Case support 13. Nut 14. Transmission case 15. Connecting plate 16. Bearing 17． Shaft neck 17a. Flange 18． Chrysanthemum nut 19. Oil seal 20. Lids B1 to B5. Bolt R, Ra. Rotor S, Sa. Stator

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Showa 57-55279 (JP, U) Japanese Patent Publication No. 49-45271 (JP, B1) Japanese Utility Model Showa 52-30468 (JP, Y1) (58) Field (Int.Cl. ⁷ , DB name) H02K 49 / 02,49 / 10

Claims (1)

(57) [Claim 1] A first spoke having one end fixed to a first spoke .
Cylindrical part and one end part are fixed by the second spokes.
A rotor having a second cylindrical portion formed therein, and a first spoke and a first spoke.
And second spokes are attached via the disc
A double eddy current reduction gear comprising a bracket, a first stator and a second stator comprising a yoke and a pole piece each having a permanent magnet inside each cylindrical portion.
The first spoke and the second spoke are interchangeable.
The first cylindrical part and the second cylindrical part are arranged in
Back-to-back around the first and second spokes
A double eddy current type reduction gear characterized by being attached to a single bracket .