JPH04111284U - Braking drum of eddy current reduction gear - Google Patents

Abstract

(57) [Summary] [Purpose] The cage-shaped conductor connected to the brake drum promotes the flow of eddy current, and at the same time improves the cooling performance of the conductor, increasing the braking capacity without any problems in terms of strength. [Structure] Annular protruding walls 13b are provided at both ends of a brake drum 13 and protrude in the axial direction, and each protruding wall 1 is provided with a conductor ring 45 having a C-shaped cross section and having a large number of fins 45a arranged at equal intervals in the circumferential direction on the outer surface.
3b. A large number of axial grooves 43 are provided at equal intervals in the circumferential direction on the inner peripheral wall of the brake drum 13, and a conductor rod 48 is fitted into the axial grooves 43. Both ends of the conductor rod 48 are connected to the pair of conductor rings 39 .

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is a special eddy current reduction gear that is mounted on large vehicles to assist friction brakes. For the braking drum of an eddy current reduction gear, which improves the flow of eddy current and enhances cooling performance. It is related to

0002

[Conventional technology]

As shown in FIG. 3, this type of eddy current reduction gear for vehicles A braking drum 13 as a rotary braking body is supported by the rotary braking member. For this reason, the transmission gear A mounting flap is attached to a rotating shaft 4 supported by a bearing 3 on the end wall of the box 2 and protruding from the end wall. The hinge 5 is spline-fitted and fastened with a nut 6 to prevent it from coming off. Tori The end wall of the brake drum 7 of the parking brake and the brake drum 1 of the reduction gear are attached to the attached flange 5. The boss portion 9 of No. 3 and the integral flange portion 9a are overlapped, and a plurality of bolts 10 and nuts It is fastened by the gate 10a.

0003 The brake drum 13 is supported by a number of spokes 12 extending radially from the boss portion 9. It will be done. Therefore, the tips of the spokes 12 are welded to the right end of the brake drum 13. will be combined. A large number of fins 13a are provided on the outer peripheral wall of the brake drum 13 at equal intervals in the circumferential direction. available. A polyurethane material such as copper is placed on the inner peripheral wall of the brake drum 13 between a pair of rings 27 made of copper or the like. A cage-shaped conductor formed by connecting several rods 28 at equal intervals in the circumferential direction is buried.

0004 A brake drum 13 made of an electrical conductor such as iron has an inner cavity with a box-shaped cross section. A cylindrical magnet guide frame 18 is provided. The magnet guide frame 18 is attached to the projecting wall 2a of the gear box 2. Fixed with bolts 32 and 33 to a frame plate 31 having reinforcing ribs 31a fixed to the outside. be done. The magnet guide frame 18 is constructed by connecting annular end wall plates to both ends of an outer cylinder and an inner cylinder. However, the illustrated magnet guide frame 18 is made of a material such as ordinary iron. A cylindrical frame portion 18a forming a letter shape and a right half portion made of a non-magnetic material such as aluminum. and a cylindrical frame portion 18b having an inverted L-shaped cross section are connected by a large number of bolts 14. It consists of

[0005] The outer cylindrical portion, that is, the frame portion 1 of the magnet guide frame 18 facing the inner circumferential wall of the brake drum 13 A large number of openings are provided at equal intervals in the circumferential direction on the peripheral wall of 8b, and a ferromagnetic plate (port) is provided in each opening. piece) 21 is fitted and fixed. In reality, the ferromagnetic plate 21 holds the frame portion 18b It is cast when casting from aluminum.

[0006] A plurality of actuators (not shown) are supported on the frame plate 31 at equal intervals in the circumferential direction. The actuator projects from the piston fitted into the cylinder into the inner cavity of the magnet guide frame 18. A magnet support ring 19 is coupled to the end of the rod 17 to be released. The magnet support ring 19 is a magnet plan. It is supported in the inner space of the inner frame 18 so as to be movable in the axial direction. On the outer peripheral surface of the magnet support ring 19, Permanent magnets 20 facing each ferromagnetic plate 21 are coupled with alternating polarities in the circumferential direction. be done.

[0007] During braking, the magnet support ring 19 is moved to the rod 1 by an actuator as shown in the figure. 7 into the interior of the brake drum 13. The rotating brake drum 13 is permanently The magnetic field passes through the ferromagnetic plate 21 from the magnet 20 to the inner peripheral wall of the brake drum 13. eddy current is generated in the brake drum 13, and the brake drum 13 receives braking torque. . The brake drum 13 generates heat due to eddy currents, and is heated directly or by air using the fins 13a. cooled down.

[0008] In the above-mentioned eddy current reduction gear, during braking, the electric resistance embedded in the brake drum 13 Since eddy currents concentrate and flow through the cage-shaped conductor consisting of the small ring 27 and rod 28, Braking ability can be increased accordingly, but the heat generated by the conductor also increases, making it difficult for the vehicle to drive down long slopes. When the brake drum 13 is continuously braked, the temperature of the brake drum 13 reaches 700°C, so the conductor There is a risk of cracking, and in such a case, take precautions to prevent damage to the brake drum 13. Therefore, braking must be interrupted.

[0009] In the eddy current reduction gear disclosed in Utility Model Application Publication No. 2-103532, an immovable magnet guide frame is used. When the brake drum crosses the magnetic field from the magnet, an eddy current is generated on the wall of the brake drum. The flow is concentrated into a cage-shaped conductor wire buried in the brake drum, and a part of the conductor wire is The brake drum is exposed to the outside and cooled directly by air, but the strength of the conductor is It becomes structurally weak and may be deformed or damaged by heat.

0010

[Problem that the invention attempts to solve]

In view of the above-mentioned problems, the purpose of this invention is to reduce the vortex by using a cage-shaped conductor connected to the brake drum. Promotes current flow and simultaneously improves conductor cooling, increasing braking ability without affecting strength. An object of the present invention is to provide a braking drum for an eddy current speed reduction device.

[0011]

[Means to solve the problem]

In order to achieve the above object, the structure of the present invention has a large number of fins arranged on the outer surface at equal intervals in the circumferential direction. A pair of conductor rings with a C-shaped cross section are fitted onto the ends of the brake drum, and the brake drum is The conductor rod is fitted into a large number of axial grooves provided at equal intervals in the circumferential direction on the inner circumferential wall of the ram. Both ends of the conductor ring are connected to the pair of conductor rings.

0012

[Effect]

When a rotating brake drum crosses a magnetic field, it generates eddy currents in the wall of the brake drum. . Eddy currents concentrate in numerous loop-shaped current-carrying circuits formed by a pair of conductor rings and conductor rods. It flows. The conductor rings fitted on both ends of the brake drum are The heat released through the fins prevents the brake drum from overheating and increases the durability of the brake drum. improve.

[0013]

[Example of idea]

Figure 1 is a front cross-sectional view of the braking drum of the eddy current speed reduction device according to the present invention, and Figure 2 is the same eddy current reduction device. FIG. 3 is a plan view showing only the conductor of the braking drum of the current type speed reduction device expanded in the circumferential direction. The brake drum 13 has a large number of axial grooves 43 with a rectangular cross section arranged at equal intervals in the circumferential direction on the inner circumferential wall 40. established in The outer circumferential wall of the brake drum 13 is thick at the center in the axial direction. A large number of fins 13a are arranged at equal intervals in the circumferential direction.

[0014] According to the present invention, annular projecting walls 13b are formed at both ends of the brake drum 13. For this purpose, notches 42 and 41 are provided in the inner and outer circumferential walls at both ends of the brake drum 13 to prevent braking. It is preferable that the base of the protruding wall 13b relative to the drum 13 be slightly constricted. Yes. A conductor ring having a C-shaped cross section and having a large number of fins 45a on the outer surface of each projecting wall 13b. 45 is fitted. The conductor ring 45 has a cylindrical portion 46 on the outer circumferential side of an annular plate portion, and a cylindrical portion 46 on the inner circumferential side. Each of them is integrally provided with a cylindrical portion 47. The fin 45a is a C-shaped thin plate, They are arranged on the outer surface of the conductor ring 45 at equal intervals in the circumferential direction.

[0015] The left and right conductor rings 45 are almost symmetrical, and the end face of the cylindrical portion 47 of the left conductor ring 45 A large number of axial conductor rods 48 arranged at equal intervals in the circumferential direction are protruded, and the conductor rods 48 are cut. It has a rectangular surface, and a pin 48a is formed at the tip. On the other hand, the conductor ring 45 on the right side is A cut is made in a portion corresponding to the welded joint between the end wall of the brake drum 13 and the spokes 12. Cutouts 50, 50a are provided. On the end face of the cylindrical wall 47 of the right conductor ring 45, there is a A large number of pin holes 49 are provided at equal intervals.

[0016] To attach the conductor ring 45 according to the invention to the brake drum 13, the left conductor ring 45 is The conductor rod 48 protruding from the cylindrical portion 47 of No. 5 is fitted into the axial groove 43 of the brake drum 13. At the same time, the radial distance between the cylindrical portion 46 and the cylindrical portion 47 is expanded, and the protruding wall of the brake drum 13 is 13b, the conductor ring 45 is tightened because the notch 41 is narrowed. It never comes off. Next, the right conductor ring 45 is attached to the protruding wall 13b of the brake drum 13. At the same time, the pin hole 49 of the cylindrical wall 47 is externally fitted to the pin 48a of the conductor rod 48. do. After welding the spokes 12 to the right end wall of the brake drum 13, the conductor ring 45 is attached. When attaching the conductor ring 45, cutouts provided in the annular plate portion and the cylindrical portion 47 of the right conductor ring 45, respectively. The cutout 50 and the cutout 50a avoid interference with the spokes 12.

[0017] In the embodiments described above, the conductor rod 48 may have a circular cross section or may be a tube, in which case The cross section of the axial groove 23 of the brake drum 13 is circular. The conductor bar 48 is connected to the conductor ring 45 It may also be formed separately and connected by fitting the pin into the pin hole. In addition, the conductor rod 48 The conductor ring 45, which has a U-shaped cross section and is integrally provided with fins, is connected to the brake drum 1. Simply fitting one or both ends of 3 improves the flow of eddy current and improves braking performance. Can increase power.

[0018] In addition, in the above embodiment, the braking drum of the eddy current reduction gear using permanent magnets is However, the present invention is not limited to this, and the present invention is not limited to this. A similar effect can be obtained by applying the present invention to a brake drum of an electric speed reducer.

[0019]

[Effect of the idea]

As mentioned above, the present invention has annular protruding walls that protrude in the axial direction at both ends of the brake drum. A conductor ring with a C-shaped cross section and a large number of fins arranged at equal intervals in the circumferential direction is attached to each projecting wall. The conductor rods are fitted into a number of axial grooves provided at equal intervals in the circumferential direction on the inner circumferential wall of the brake drum. and both ends of the conductor rod are connected to the pair of conductor rings, and the rotating control When the moving drum crosses a magnetic field, the eddy currents generated in the wall of the braking drum flow through a pair of conductors. The current flows concentratedly into numerous loop-shaped current-carrying circuits formed by rings and conductor rods, producing braking torque. Occur. The cage-shaped conductor improves the flow of eddy currents, thereby increasing braking capacity. Ru. The heat generated by the eddy current flowing through the conductor rod is generated by the conductor rings fitted to both ends of the brake drum. Air cooling through the fins prevents the brake drum from overheating and improves braking performance. Improves drum durability.

[Brief explanation of drawings]

FIG. 1 is a front cross-sectional view of a brake drum of an eddy current speed reduction device according to the present invention.

2 is a plan view showing a cage-shaped conductor attached to the brake drum developed in the circumferential direction and partially cut away along line 2A-2A in FIG. 1; FIG.

FIG. 3 is a side cross-sectional view of an eddy current speed reduction device equipped with a conventional general braking drum.

[Explanation of symbols]

13: Braking drum 13b: Projection wall 45: Conductor ring 45
a: Fin 48: Conductor rod

Continuation of front page (72) Creator Masayuki Sano 3-25-1 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside Isuzu Motors Kawasaki Plant

Claims (1)

[Scope of utility model registration request] Claim 1: A pair of conductor rings having a C-shaped cross section and having a large number of fins arranged at equal intervals in the circumferential direction on the outer surface are fitted to the ends of the brake drum, and are attached to the inner peripheral wall of the brake drum at equal intervals in the circumferential direction. The conductor rod is fitted into the many axial grooves provided, and both ends of the conductor rod are connected to the
A braking drum of an eddy current reduction device, characterized in that it is coupled to a pair of conductor rings.