JP2577314Y2 - Brake drum of eddy current reduction device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking drum for an eddy current reduction device mounted on a vehicle or the like, and more particularly to a braking drum which is not affected by thermal expansion.

[0002]

2. Description of the Related Art When a rotating braking drum crosses a magnetic field, the braking drum absorbs the power of the rotating shaft as eddy current generated inside the braking drum, and finally converts the power into heat. Since the brake drum diverges, the brake drum generates heat and expands and deforms. However, if the temperature of the braking drum becomes non-uniform in the radial direction, the thermal expansion of the braking drum also becomes non-uniform, causing excessive thermal stress on the braking drum, which may damage the braking drum.

In the brake drum of the eddy current reduction device disclosed in Japanese Utility Model Laid-Open No. 57-115576 and Japanese Utility Model Laid-Open No. 3-117375, the inner peripheral surface of the brake drum is prevented in order to prevent the brake drum from being damaged due to heat generation. A rod protruding radially inward from the boss is slidably fitted to a support cylinder protruding radially outward from the boss to allow free thermal expansion of the brake drum and reduce thermal stress. However, it takes time and effort to machine the support cylinder on the boss, and the rod is fitted to the support cylinder and then welded to the brake drum. Accordingly, since the rod slides along the support cylinder, play is likely to occur due to wear of the sliding portion.

In a brake drum and a boss portion which are integrally connected by a spirally curved spoke, the spoke is freely deformed due to the thermal expansion of the brake drum, thereby allowing the brake drum to expand and deform. If the rigidity for supporting the brake drum is low and the deformation (bending) between the spokes is different, the brake drum may be eccentric with respect to the boss portion. Extreme stress on the shaft, very dangerous.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is easy to assemble a connecting member for connecting a brake drum and a boss portion, and the connecting member can easily rotate the brake drum. It is an object of the present invention to provide a very stable braking drum for an eddy current reduction device.

[0006]

In order to achieve the above-mentioned object, according to the structure of the present invention, a plurality of protruding pieces projecting outward from the boss portion are provided at equal intervals in a circumferential direction on a boss portion connected to a rotating shaft. The same number of protrusions as the protrusions protruding inward from the ends at the ends of the brake drum are provided at equal intervals in the circumferential direction, and the protrusions of the boss portion and the protrusions of the brake drum are rotated. It is characterized by being connected by a connecting plate extending in the circumferential direction of the shaft.

Further, in the construction of the present invention, a plurality of projections projecting radially outward from the boss portion are provided at equal intervals in the circumferential direction on the boss portion connected to the rotating shaft, and the end portion of the braking drum is provided at the end portion. The same number of protrusions as the protrusions projecting radially inward from are provided at equal intervals in the circumferential direction, and the protrusions of the boss portion and the protrusions of the braking drum are connected by a connection plate extending in the axial direction of the rotating shaft. It is characterized by having done.

[0008]

The projection projecting outward from the boss and the projection projecting inward from the braking drum are connected by a connecting plate. Therefore, when the boss rotates, the connecting plate receives the tensile stress, stably supports the braking drum, and transmits the rotation of the boss to the braking drum. The connecting plate is only slightly curved, and can maintain a stable rotation of the brake drum, in response to the expansion deformation caused by the thermal expansion of the brake drum.

Since the connecting plate is connected at both ends to the projecting piece of the boss and the projecting piece of the braking drum by bolts, it is very easy to assemble, and the eccentricity (center misalignment) of the braking drum with respect to the rotation axis of the boss. The movement is suppressed by the equilibrium movement between the plurality of connecting plates, and the braking drum is held concentrically with the boss.

[0010]

FIG. 1 is a front view of a braking drum of an eddy current reduction device according to the present invention. The brake drum 12 and the boss portion 3 having the shaft hole 2 are formed separately, and are connected to each other by the connection plate 8. The boss 3 is formed with a plurality of projecting pieces 4 projecting outward from the peripheral wall in parallel with the radial line 20 at equal intervals in the circumferential direction. In the illustrated example, the boss 3 is formed with four projecting pieces 4, and each of the projecting pieces 4 is provided with an end face 4 a perpendicular to the radial line 20 at the end. On the other hand, the braking drum 12 has the same number of protrusions 12a as the protrusions 4 protruding inward from the inner circumferential surface of the end in parallel with the radial line 20 at equal intervals in the circumferential direction. An end face 12b perpendicular to the line 20 is provided. Protruding piece 4
And the length of the protruding piece 12a is equal to the end face 4a of each set of the protruding piece 4 and the protruding piece 1
It is determined so that the end surface 12b of the second surface 2a is flush with the end surface 12b.

The connecting plate 8 is superposed on the end face 4a and the end face 12b, and connected by bolts 5 and 13, respectively. The protruding piece 12 a is disposed on one end side of the braking drum 12 for convenience of disposing a stationary magnet support frame inside the braking drum 12.

According to the present invention, when the rotating shaft fitted and fixed to the shaft hole 2 of the boss portion 3 is rotated in the direction of the arrow x, the rotation of the boss portion 3 is transmitted to the brake drum 12 via the connecting plate 8. Is transmitted. At this time, since the connecting plate 8 only receives a tensile stress, there is no problem. Even if the connecting plate 8 is relatively thin, the strength is sufficient. During braking, when the braking drum 12 generates heat due to eddy current flowing through the braking drum 12, the braking drum 1
2 is uniformly expanded radially outward, and the connecting plate 8 is slightly curved. At this time, the connecting plate 8 does not prevent the braking drum 12 from expanding, and the connecting plate 8 does not receive an excessive force. Since the connecting plates 8 are arranged at equal intervals in the circumferential direction and are uniformly curved, the braking drum 12 does not receive an excessive force due to the expanding deformation, and the braking drum 12 does not receive an excessive force with respect to the axis of the boss portion 3 of the braking drum 12. There is no loss of concentricity.

In the embodiment shown in FIG. 2, the connecting plate 8A extends not in the circumferential direction but in the axial direction, and the boss portion 3 and the braking drum 12
Concatenate. The base end of a substantially triangular connecting plate 8A is connected to the end surface of each protruding piece 4 extending radially outward from the boss 3 by a plurality of bolts 5, and the distal end of the connecting plate 8A is
2 is connected to an end face of a protruding piece 12a projecting radially inward from an end of the second piece 2 by a bolt (not shown). In the embodiment of FIG.
The direction of the projecting piece 4 and the projecting piece 12a is the radial line 20 (see FIG. 1).
Matches. The plurality of protruding pieces 4, 12a are arranged symmetrically with respect to the axis, so that they are easy to process.

In this embodiment, the rotation of the boss 3 is transmitted to the braking drum 12 via the connecting plate 8A.
Exhibits high rigidity because it receives bending stress on the plate surface. When the braking drum 12 expands and deforms due to heat generation, the connecting plate 8A
Is slightly curved but has little effect on the stiffness to the transmission torque.

FIG. 3 is a plan view of a braking drum according to a third embodiment of the present invention, and FIG. 4 is a side view taken along line 4A-4A of FIG. The protruding piece 4 protrudes radially outward from the boss portion. An end face 4a for connecting the connecting plate 8B is formed at the tip, a step surface 4c and a shoulder 4b are integrally formed on one side, and a screw hole 5a is provided on the end face 4a. Can be The shoulder 4 b has an outer peripheral surface corresponding to the inner peripheral surface of the braking drum 12. The braking drum 12 has a protruding piece 12a protruding in the axial direction from an end face 12c, and a screw hole 13a is provided in a flat peripheral surface 12b. End face 4a of projecting piece 4 and projecting piece 12
The peripheral surface 12b of a is not perpendicular to the radial line. The braking drum 12 is fitted over the shoulder 4b of the projection 4 and
2c is brought into contact with the step surface 4c. Projection piece 1 of braking drum 12
2a is separated in the circumferential direction from the projecting piece 4 of the boss portion, the connecting plate 8B is superimposed on the end face 4a and the peripheral face 12b, and the bolts 5, 13
Are screwed into the screw holes 5a and 13a, respectively.

In this embodiment, the shoulder 4 of the boss 4
Positioning is easy because b is fitted to the braking drum 12. Due to the expansion deformation accompanying the heat generation of the brake drum 12, the brake drum 12 separates from the shoulder 4b, and at the same time, the rotational phase between the boss 3 and the brake drum 12 changes.

[0017]

As described above, in the present invention, a plurality of projecting pieces projecting outward from the boss portion are provided at equal intervals in the circumferential direction on the boss portion connected to the rotating shaft, and the boss portion is provided at the end of the braking drum. The same number of protrusions as the protrusions projecting inward from the ends are provided at equal intervals in the circumferential direction, and the protrusions of the boss portion and the protrusions of the braking drum extend in the circumferential direction or the axial direction of the rotating shaft. Since the boss portion and the braking drum are connected by the connecting plate, it is very easy to assemble the boss portion and the braking drum, and the connecting plate transmitting the rotation of the boss portion to the braking drum receives a tensile stress or a bending stress on the plate surface. It ’s just that.

In response to the expansion deformation caused by the heat generated by the braking drum,
The connecting plate is only slightly curved and does not hinder the deformation of the brake drum, so that no excessive thermal stress is generated in the brake drum.

When the brake drum rotates, the connecting plate receives a tensile stress or a bending stress in the plane of the plate and acts to hold the brake drum concentrically with the boss portion, so that the rotation of the brake drum is very stable. It is.

Since there is no sliding portion between the boss portion and the braking drum, there is no wear or backlash and excellent reliability and durability.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a braking drum of an eddy current reduction device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a braking drum of the eddy current reduction device according to the second embodiment of the present invention.

FIG. 3 is a plan view of a braking drum of an eddy current reduction device according to a third embodiment of the present invention.

FIG. 4 is a side sectional view taken along line 4A-4A of FIG. 3;

[Explanation of symbols]

3: Boss part 4, 12a: Projection piece 5, 13: Bolt
8, 8A, 8B: Connecting plate 12: Brake drum

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hayao Isoyama 3- 25-1, Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Pref. Isuzu Motor Co., Ltd. Kawasaki Plant (58) Field surveyed (Int. Cl. ⁶ , DB name) H02K 49/02

Claims (2)

(57) [Scope of request for utility model registration] A boss connected to a rotating shaft is provided with a plurality of projecting pieces projecting outward from the boss at regular intervals in a circumferential direction, and projecting inward from the end at an end of a braking drum. A vortex, wherein the same number of the projecting pieces as the projecting pieces are provided at equal intervals in the circumferential direction, and the projecting pieces of the boss portion and the projecting pieces of the braking drum are connected by a connecting plate extending in the circumferential direction of the rotating shaft. The braking drum of the current reduction device. 2. A boss portion connected to the rotating shaft is provided with a plurality of projections projecting radially outward from the boss portion at equal intervals in a circumferential direction, and is provided at an end portion of the braking drum radially inward from the end portion. The same number of projecting pieces as the projecting pieces are provided at regular intervals in the circumferential direction, and the projecting pieces of the boss portion and the projecting pieces of the braking drum are connected by a connecting plate extending in the axial direction of the rotating shaft. Eddy current reduction gear brake drum.