JP4007223B2 - Eddy current reducer - Google Patents

Description

表１の評価結果から、本発明例１〜３では、比較例に比べて、制動および非制動を繰り返した場合に、制動ディスクの表面に生じる非弾性ひずみ範囲が小さい。前述の通り、非弾性ひずみ範囲が大きいほど、熱疲労亀裂の発生までの寿命は短くなることから、本発明例１〜３は、比較例に比べて、熱疲労亀裂の発生を抑制でき、装置の耐久性を向上させることができることが分かる。
【００６５】
以上の通り、本発明の実施の形態および実施例を例示して説明したが、本発明はこれらの実施例に何ら限定されるものではなく、特許請求の範囲に示された技術思想の範疇において変更可能である。
【００６６】
【発明の効果】
本発明の渦電流減速装置であれば、制動ディスクの内周部が回転軸に直接固定されず、環状制動ディスクであるため、半径方向の幅が小さく、半径方向に形成される温度差は小さくなり、制動ディスクに発生する非弾性ひずみが低減され、長期間使用した場合であっても、制動ディスクが変形して制動力が低下したり、熱疲労亀裂が発生することを防止できる。
【００６７】
これにより、制動時の磁気効率に優れ、簡易な構造で小型、軽量化が可能であるとともに、装置の耐久性と寿命を著しく向上させることができる。
【図面の簡単な説明】
【図１】永久磁石を用いて対向する導体内に渦電流を生じさせる渦電流減速装置の構成例を示す断面図である。
【図２】本発明に基づく第１の減速装置の断面構成例を示す図である。
【図３】本発明に基づく第１の減速装置で採用する制動ディスクおよび制動ディスク保持部材の構造例（Ｘ−Ｘ視野正面図）を示す図である。
【図４】制動ディスクを回転軸の中心を通る放射状の直線に対して回転方向に傾斜したリブを介して支持ディスクに接続した構成を示す図である。
【図５】制動ディスクを回転軸の中心を通る放射状の直線に対して回転方向に湾曲したリブを介して支持ディスクに接続した構成を示す図である。
【図６】制動ディスクを回転軸の中心を通る放射状の直線に対して回転方向に湾曲したリブを介して支持ディスクに接続し、このリブを制動ディスクの内周側よりもさらに内側に突出した構成を示す図である。
【図７】本発明に基づく第２の減速装置の構成を例示する図であり、（ａ）は断面構成例を示し、（ｂ）は制動ディスクおよび制動ディスク保持部材の構造例（Ｙ−Ｙ視野正面図）で示す図である。
【図８】本発明に基づく第３の減速装置の構成を例示する図であり、（ａ）は断面構成例を示し、（ｂ）は制動ディスクおよび制動ディスク保持部材の構造例（Ｚ−Ｚ視野正面図）で示す図である。
【符号の説明】
１：回転軸、 ２、２１：制動ディスク
３：案内筒、 ３ａ：ポールピース
４：保持リング、 ５：シリンダー
６：ピストンロッド、 ７：磁石、永久磁石
８：制動ディスク保持部材、 ８ａ：リブ
８ｂ：支持ディスク（支持板）
８ｃ：背面ディスク（背面板）
９：冷却用フィン[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disk-type eddy current reduction device that assists a main brake used in a vehicle such as an automobile. More specifically, the present invention is excellent in braking efficiency during braking, can be reduced in size and weight with a simple structure, and can be used for a long time. The present invention relates to an eddy current reduction device that can ensure stable braking force and durability even when used over a wide range.
[0002]
[Prior art]
In braking systems for automobiles such as trucks and buses, in addition to foot brakes, which are the main brakes, exhaust brakes, which are auxiliary brakes, stable deceleration on long downhill slopes, etc. In order to prevent burning, an eddy current reduction device is used.
[0003]
As a conventional eddy current reduction device, there is a system in which an eddy current is generated in an opposing conductor while rotating using a permanent magnet, and braking is applied to a rotating shaft of a vehicle by Lorentz force. Usually, in this type of reduction gear, a guide cylinder configured to house a permanent magnet and move the permanent magnet to the switching position inside, and a rotor portion connected to the rotating shaft of the vehicle body outside the guide cylinder, It is composed of
[0004]
[Problems to be solved by the invention]
In recent years, the number and types of vehicles equipped with eddy current reduction devices have increased, and the performance required for eddy current reduction devices has diversified and at the same time advanced. Performance is required.
[0005]
Specifically, in a vehicle type that continuously uses an eddy current reduction device, the braking disk is exposed to a high temperature for a long time, so that the thermal deformation that occurs is increased. Further, in a vehicle type that frequently repeats braking and non-braking, thermal fatigue cracks occur because inelastic strain is repeatedly applied to the braking disk many times. For this reason, it is required to prevent thermal deformation and thermal fatigue cracks of the braking disk, improve the durability of the device, and extend the life of the device.
[0006]
The present invention has been made in view of the improvement in durability of the eddy current reduction device, and is excellent in braking efficiency during braking, can be reduced in size and weight with a simple structure, and has been used for a long time. Even if this is the case, it is possible to suppress the deformation of the braking disk, to ensure a stable braking force, and to provide an eddy current reduction device that can prevent thermal fatigue cracks and improve durability. The purpose is to do.
[0007]
[Means for Solving the Problems]
FIG. 1 is a cross-sectional view showing a configuration example of an eddy current reduction device that generates eddy currents in opposing conductors using a permanent magnet. Although the detailed operation and configuration of each part of the apparatus such as the guide cylinder 3 and the cylinder 5 will be described later, the brake disk 21 is disposed so as to face the permanent magnet 7, and an eddy current is generated inside during braking. The braking disk 21 shown in FIG. 1 has a structure in which an inner peripheral portion is attached to the rotary shaft 1 and fixed. Further, cooling fins 9 are provided on the back surface of the brake disk 21.
[0008]
When the magnetic force exerted by the permanent magnet is applied perpendicularly to the brake disk, an eddy current is generated in the brake disk from the relative speed difference when the brake disk rotating on the magnetic field line crosses, and Joule heat is generated. Although the brake disk thermally expands due to this heat generation, since the inner peripheral portion thereof is fixed to the rotating shaft, the thermal expansion in the radial direction is restricted.
[0009]
In the braking disk at the time of braking, the portion facing the permanent magnet becomes high temperature due to Joule heat, but the amount of heat generation is smaller on the inner peripheral side and outer peripheral side than that portion, and the temperature is lower than the portion facing the permanent magnet. Therefore, the braking disk has a high temperature portion facing the permanent magnet and low temperature portions located on the inner and outer peripheral sides thereof. At this time, the thermal expansion amount of the braking disk increases as the temperature increases, but the thermal expansion amount of the high temperature portion facing the permanent magnet is constrained by the surrounding low temperature portion, that is, the region where thermal expansion is small. As a result, inelastic strain (plastic strain and creep strain) is generated in the high temperature portion of the brake disk.
[0010]
When the brake disk is used for a long period of time, this inelastic strain accumulates, resulting in residual deformation, and the deformation of the brake disk gradually increases. When the deformation of the brake disk increases, the distance between the permanent magnet and the brake disk surface changes, so that the magnetic force acting on the brake disk changes and the braking efficiency decreases.
[0011]
Furthermore, by repeating braking and non-braking using the braking disk for a long period of time, inelastic strain is repeatedly applied to the braking disk, and thermal fatigue cracks are generated. When a thermal fatigue crack occurs, the eddy current generated in the disk decreases, and the braking efficiency decreases.
[0012]
  In order to suppress the above-described deformation of the brake disk and generation of thermal fatigue cracks, it is necessary to suppress inelastic strain generated in the brake disk. For this reason, it is effective to adopt a structure in which the inner peripheral portion of the brake disk is not directly fixed to the rotating shaft and a structure in which a temperature difference is not easily formed in the radial direction of the brake disk. The present invention has been completed on the basis of such findings, and the gist of the present invention is an eddy current reduction device described below.
(1) An eddy current reduction device according to the present invention includes an annular braking disk for generating a braking force applied to a rotating shaft of a vehicle, and one main surface of the annular braking disk attached to the rotating shaft. A brake disc holding member connected to the annular brake disc, a holding ring movable in a direction approaching and separating from the other main surface of the annular brake disc, and the annular brake disc in a circumferential direction of the holding ring And a plurality of first permanent magnets having adjacent magnetic pole faces arranged in opposite directions, and the first permanent magnet approaches the annular braking disk and is in a braking state. And a position that is away from the annular braking disk and is in a non-braking state.And the braking disk holding member is attached to the rotating shaft while holding the ribs, and a plurality of ribs extending from the inner peripheral side to the outer peripheral side on the one main surface of the annular braking disk, And a support plate that forms a cavity between the rib and the annular braking disk.It is characterized by that.
[0013]
The “annular brake disc” defined above is a shape in which the inner peripheral portion of the brake disc is not fixed to the rotating shaft and at the same time it is difficult to form a temperature difference in the radial direction in order to suppress inelastic strain generated in the brake disc. It is what. Although the basic shape of the brake disk of the present invention is a circular ring shape, it is not necessarily limited to a circular shape, and can be adopted as long as the start point and the end point of the ring portion are continuous and have a continuous shape. .
[0014]
  The basic shape is not limited to the circular ring shape, and the start point and the end point of the ring portion are continuous, and the shape is seamless, and the same applies to the holding ring. The annular braking disk and the retaining ring are at least similar and more preferably congruent when projected from above the main surface of the annular braking disk, and most preferably on the similar or congruent shape of each other. It has no rotation angle.
(2) Further, an eddy current reduction device according to the present invention includes an annular braking disk for generating a braking force applied to a rotating shaft of a vehicle, and one main body of the annular braking disk attached to the rotating shaft. A braking disk holding member connected to the annular braking disk at a surface, a holding ring that is held in contact with and close to the other main surface of the annular braking disk, and the annular braking in a circumferential direction of the holding ring A plurality of composite magnets including at least one second permanent magnet and at least one switching electromagnet are provided facing one main surface of the disk, and the magnetic pole surfaces of the adjacent composite magnets are opposite to each other. Placed inAnd the braking disk holding member is attached to the rotating shaft while holding the ribs, and a plurality of ribs extending from the inner peripheral side to the outer peripheral side on the one main surface of the annular braking disk, And a support plate that forms a cavity between the rib and the annular braking disk.It is characterized by that.
[0015]
Here, “composite magnet” refers to a magnet in which a permanent magnet and an electromagnet are combined with a magnet. For example, by adopting a so-called hybrid type that changes the magnetic path of a permanent magnet by turning an electromagnet on and off as a composite magnet, it is possible to switch between braking and non-braking without providing a holding ring drive unit by a cylinder. become.
[0016]
In the following description, the term “magnet” simply refers to at least one of a permanent magnet (first permanent magnet) and a combination of a permanent magnet (second permanent magnet) and an electromagnet. Indicates.
[0017]
The “main surface of the annular braking disk” refers to an annular disk surface having a wide and flat plane among the four surfaces of the annular braking disk, the front and back annular disk surfaces, the outer peripheral surface, and the inner peripheral surface. Incidentally, one of the front and back board surfaces (any main surface) faces the magnetic force.
[0018]
Next, “approaching” means that sufficient magnetic field lines reach the rotating annular braking disk from the magnet, generate sufficient eddy current in the annular braking disk, convert rotational energy into heat, rotate This means that the magnet or the holding ring that holds the magnet and the annular brake disk are close enough to allow sufficient braking to be applied to the annular brake disk.
[0019]
“Separate” means that the magnet or the retaining ring that holds the magnet and the annular ring are such that the magnetic lines of force from the magnet hardly reach the annular braking disk, and as a result, almost no eddy current is generated in the annular braking disk. The state where the brake disc is moving away.
[0020]
Further, the “magnetic pole surface” refers to a surface of a magnet that can generate a magnetic flux that passes perpendicularly to the main surface of the stationary braking disk among the “surfaces” that form the magnet shape. In other words, the surface of the magnet facing the main surface of the brake disk can also be referred to as a magnetic pole surface, and mainly refers to a certain surface of the magnet shape itself. In the case of the above-described composite magnet that emits magnetic flux, or when the shape of the magnet is uneven, and a magnetic flux is emitted from a plurality of magnet surfaces, a surface from which the magnetic flux is virtually generated may be defined and used as the magnetic pole surface.
(3) In the eddy current reduction device according to the present invention, the annular braking disk is provided at a position facing the magnetic pole surface of the magnet, and the ring width (from the center of the rotating shaft to the radial direction of the rotating shaft). The length of the ring) has a width equal to or greater than the radial length with respect to the rotation axis of the magnet.
[0021]
  With this configuration, the magnetic force exerted by the magnet can be sufficiently applied to the brake disc, and the brake disc is annular, so that its radial width is a disc-like shape fixed to the rotating shaft. Therefore, the temperature difference formed in the radial direction of the brake disk is smaller..
[0022]
  The brake disk holding member is configured to include a rib and a support plate.BecauseA cavity is formed between the two adjacent ribs, the annular braking disk, and the support plate, so that the amount of air flowing therethrough can be secured and the cooling capacity of the braking disk can be increased. Further, by projecting the rib further inward than the inner peripheral side of the annular braking disk, air can be actively sent into the cavity, and the cooling capacity of the braking disk can be further enhanced..
(FourThe rib used in the eddy current reduction device according to the present invention may be configured as a heat dissipation fin of the annular braking disk. As a result, even during braking, the cooling performance of the braking disk is increased and the temperature of the disk is less likely to rise, so the temperature difference formed in the radial direction of the disk is reduced and the inelastic strain generated in the braking disk is reduced. it can.
[0023]
The rib used here may be configured to be inclined in the rotational direction with respect to a radial straight line passing through the center of the rotation axis, or may be configured to be further curved in the rotational direction. By doing so, air can easily flow through the formed cavity, and the cooling effect by air can be enhanced.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
The example of a structure of the eddy current reduction device based on this invention mentioned above is demonstrated using a concrete drawing.
[0025]
FIG. 2 is a diagram showing a cross-sectional configuration example of the first reduction gear device according to the present invention. In the first reduction gear, the brake disk holding member 8 is constituted by a combination of a support disk (support plate) 8b and a rib 8a. In the eddy current reduction device shown in FIG. 2, a support disk 8b attached to the rotating shaft 1 of the vehicle, an annular braking disk 2 connected to the support disk 8b via a rib 8a on one main surface thereof, A guide tube 3 attached to the non-rotating part is provided. The annular braking disk 2 is fixed to the rotary shaft 1 by connection with the support disk 8b via the rib 8a.
[0026]
A holding ring 4 is accommodated in the guide tube 3 so as to be movable toward and away from the braking surface (main surface) of the annular braking disk 2. Further, the guide tube 3 moves the holding ring 4 forward and backward. A cylinder 5 is provided. On the other hand, a pole piece 3a made of a ferromagnetic material is disposed on the end face of the guide cylinder 3 facing the annular braking disk 2.
[0027]
The guide cylinder 3 shown in FIG. 2 has a structure in which a pole piece 3a made of a ferromagnetic material is disposed on the end surface facing the brake disk 2, but in the eddy current reduction device of the present invention, the guide cylinder 3 The end face of the guide tube may be made of a non-magnetic material without arranging the pole piece on the end face facing the brake disk. If the durability and weather resistance are satisfactory, the guide tube itself need not be provided.
[0028]
A plurality of magnets 7 are arranged in the circumferential direction on the surface of the retaining ring 4 facing the annular braking disk 2. The magnetic pole surface of the magnet 7 faces the braking surface (main surface) of the annular braking disk 2, and the magnetic pole surfaces of the adjacent magnets 7 are arranged in opposite directions. In the eddy current reduction device of the present invention, at least a permanent magnet is used as the magnet 7, but as described above, a so-called hybrid type in which a permanent magnet and an electromagnet are combined can also be adopted.
[0029]
The guide tube 3 that accommodates the retaining ring 4 and the magnet 7 is made of a nonmagnetic material such as aluminum, stainless steel (austenitic), or resin, and the thickness thereof is not particularly defined, but the end surface that faces the magnet of the guide tube 3 Is desirable to be thin. Moreover, when providing the pole piece 3a in the end surface of the guide cylinder 3, when producing a guide cylinder by casting, the method of casting a pole piece integrally is employable, for example.
[0030]
On the other hand, since the eddy current is generated inside the annular braking disk 2 at the time of braking and Joule heat is generated, for example, a steel containing iron as a main component, such as Cr-Mo heat resistant steel (JIS SCM415), is used. it can.
[0031]
Here, when a permanent magnet is used as the magnet 7, the operation and action during braking and non-braking are as follows. The driving mechanism of the magnet 7 includes a cylinder 5 disposed on the outer end wall of the guide cylinder 3, and a piston rod 6 fitted to the cylinder 5 passes through the outer end wall of the guide cylinder 3 and is coupled to the holding ring 4. With this configuration, the holding ring 4 can be moved in the direction perpendicular to the annular braking disk 2 in this example by the operation of the cylinder 5 in the approaching direction and in the separating direction.
[0032]
At the time of braking, the piston rod 6 of the cylinder 5 moves to the right (in the approaching direction), the holding ring 4 moves forward in the direction of the rotation axis of the annular braking disk 2, and the magnet 7 approaches the braking disk. At this time, when the annular braking disk 2 that rotates the magnetic lines of force exerted on the braking surface (main surface) of the annular braking disk 2 by each magnet 7 crosses, an eddy current flows through the annular braking disk 2 from the relative speed difference, and braking torque is generated. Occurs.
[0033]
When switching to non-braking, the operation of the cylinder 5 is switched, and the holding ring 4 directly connected to the piston rod 6 is moved to the left (in the direction of leaving), so that the magnet 7 acts as a braking surface (main part) of the annular braking disk 2. The magnetic field lines exerted on the annular braking disk 2 by the magnet 7 are weakened so that the braking torque hardly acts.
[0034]
FIG. 3 is a diagram showing a structural example (XX view front view) of an annular braking disk and a braking disk holding member employed in the first reduction gear device according to the present invention. In the configuration example shown in the figure, an annular braking disk 2 that generates a braking force by the magnetic force of a magnet during braking is connected to a support disk (support plate) 8b via a rib 8a that is an intermediate member.
[0035]
The annular braking disk 2 shown in FIG. 3 is formed of a circular annular (ring-shaped) flat plate. However, in the present invention, the shape is not limited to such a shape so that the inner peripheral portion is not restrained. What is necessary is just to be comprised by the cyclic | annular form.
[0036]
As shown in FIG. 3, by connecting the annular braking disk 2 to the support disk 8b and fixing it to the rotating shaft, even if eddy current is generated during braking and Joule heat is generated, Since the inner peripheral portion is not directly fixed to the rotating shaft, there are few constraints due to thermal expansion. Further, since the brake disc is annular, its radial width is smaller than that of the disc-like brake disc fixed to the rotating shaft, and the temperature difference formed in the radial direction of the brake disc is small. Therefore, the degree to which the thermal expansion of the high-temperature part facing the magnet is constrained by the surrounding low-temperature part, that is, the part where the thermal expansion is small is also reduced.
[0037]
As described above, when the restraint against the thermal expansion of the brake disk that becomes the high temperature part facing the magnet is reduced, the inelastic strain generated in the brake disk is reduced, and the deformation of the brake disk due to long-term use is suppressed, and the braking force is reduced. Can be prevented. Furthermore, inelastic strain repeatedly applied to the brake disk when braking and non-braking are repeated can reduce the occurrence of thermal fatigue cracks.
[0038]
In the annular braking disk 2 shown in FIG. 3, a cavity is formed by two adjacent ribs 8a, the annular braking disk 2 and the support disk 8b. As the annular braking disk 2 rotates, air flows from the inner peripheral portion to the outer peripheral portion in the cavity to cool the annular braking disc 2. If the amount of air flowing through the cavity increases, the cooling performance increases and the temperature rise of the annular braking disk 2 can be suppressed. As a result, the thermal expansion of the brake disk is reduced, and inelastic strain generated in the brake disk can be suppressed. Therefore, in order to maintain the braking efficiency of the braking disk and improve the durability of the device, it is desirable to have a structure in which the amount of air flowing through the cavity increases.
[0039]
FIG. 4 is a diagram exemplifying a configuration in which the annular braking disk is connected to the support disk via ribs inclined in the rotation direction with respect to a radial straight line passing through the center of the rotation axis. By inclining the rib 8a with respect to the rotation direction, air can easily flow from the inner peripheral side to the outer peripheral side in the formed cavity, and the amount of air flowing can be increased. As a result, it is possible to improve the cooling performance of the brake disk and suppress the temperature rise, maintain the braking efficiency of the brake disk, and improve the durability of the device.
[0040]
FIG. 5 is a diagram exemplifying a configuration in which the annular braking disk is connected to the support disk via ribs curved in the rotation direction with respect to a radial straight line passing through the center of the rotation axis. By making the rib 8a curved, it becomes easier for air to flow from the inner peripheral side to the outer peripheral side in the formed cavity, and the cooling effect by the circulating air can be enhanced.
[0041]
Further, by curving the rib 8a itself, the surface area of the side surface of the rib 8a can be increased as compared with the case where the rib 8a is simply tilted, and the amount of heat released by the circulating air can be increased. As a result, it is possible to further improve the cooling performance of the braking disk and suppress the temperature rise, maintain the braking efficiency of the braking disk, and improve the durability of the device.
[0042]
FIG. 6 shows that the annular brake disk is connected to the support disk via a rib inclined in the rotational direction with respect to a radial straight line passing through the center of the rotation axis, and this rib is further inside than the inner peripheral side of the brake disk. It is a figure which illustrates the structure which protruded. By causing the rib 8a to protrude toward the inner peripheral side of the braking disk, air can be actively circulated into the cavity. That is, since the air striking the protruding portion of the rib is introduced into the cavity, the amount of air flowing through the cavity is increased, the cooling performance of the brake disk is enhanced, and the temperature increase of the brake disk can be suppressed.
[0043]
FIG. 7 is a diagram illustrating the configuration of the second reduction gear according to the present invention, in which (a) shows an example of a cross-sectional configuration thereof, and (b) shows the structure of the annular braking disk and the braking disk holding member. It is a figure shown in an example (YY visual field front view).
[0044]
The braking disk holding member 8 shown in FIG. 7 is configured by a combination of a rib 8a attached to the rotary shaft 1 and an annular back disk (back plate) 8c. In the second reduction device, an annular braking disk 2 and an annular rear disk 8c are connected to the opposite side of the rib 8a attached to the rotating shaft 1 of the vehicle, and the annular braking disk 2 has a rim 8a. Via the rotary shaft 1 and rotate together with the rotary shaft 1. The inner diameter of the back plate is appropriately designed in relation to the amount of air, and may be smaller than the inner diameter of the brake disk or larger than the outer diameter.
[0045]
By adopting the configuration shown in FIG. 7, as in the case of the first reduction gear, even when eddy current is generated during braking and Joule heat is generated at the same time, there is little restraint due to thermal expansion, and braking is performed. Since the temperature difference in the radial direction of the disk is reduced, inelastic strain generated in the brake disk is reduced, and deformation of the brake disk due to long-time use is suppressed, so that a reduction in braking force can be prevented. Furthermore, the occurrence of thermal fatigue cracks can be suppressed even when braking and non-braking are repeated.
[0046]
Also in the second reduction gear, in order to increase the amount of air flowing through the cavity formed by the two adjacent ribs 8a, the annular braking disk 2 and the rear disk 8c, It can be inclined or curved in the rotational direction with respect to a radial straight line passing through the center of the rotation axis.
[0047]
FIG. 8 is a diagram illustrating the configuration of a third reduction gear according to the present invention, in which (a) shows an example of a cross-sectional configuration thereof, and (b) shows the structure of an annular braking disk and a braking disk holding member. It is a figure shown in an example (ZZ visual field front view).
[0048]
In the third reduction gear, the brake disk holding member 8 is configured only by the ribs 8a. In the eddy current reduction device shown in FIG. 8, the rib 8a attached to the rotating shaft 1 of the vehicle and the annular braking disk 2 are connected to the rib 8a, and the rib 8a is configured as a heat dissipation fin for the braking disk. There is no connection of the rear disk (back panel).
[0049]
By adopting the configuration shown in FIG. 8, as in the case of the first and second reduction gears, there is little restraint due to thermal expansion even during braking, and the temperature difference in the radial direction of the braking disk is small. As a result, inelastic strain generated in the brake disk is reduced, and deformation of the brake disk due to long-term use and occurrence of thermal fatigue cracks due to repeated braking and non-braking can be suppressed.
[0050]
Even in the third reduction gear, in order to improve the heat dissipation efficiency of the rib used as the heat dissipation fin of the brake disk, the rib is inclined in the rotational direction or curved with respect to the radial straight line passing through the center of the rotating shaft. It is effective to do.
[0051]
In the first to third reduction gears described above, an annular braking disk and a rib, a rib and a support disk (support plate), or a rib and a back disk (back plate) are connected. You may do it. In addition, the above-mentioned connection may be performed by connecting the respective members by welding or bolting.
[0052]
【Example】
In order to confirm the effect of the eddy current reduction device of the present invention, a finite element method (FEM) analysis was performed to evaluate the inelastic strain range generated on the surface of the braking disk when braking and non-braking were repeated. Specifically, when the examples of the reduction gears 1 to 3 based on the present invention and the comparative example are used as test materials, the maximum temperature of the braking disk is 650 ° C., the minimum temperature is 100 ° C., and this thermal cycle is applied. The range of inelastic strain produced in this was evaluated.
[0053]
However, the inelastic strain range represents the width of the value of inelastic strain generated on the surface of the brake disc when braking and non-braking are repeated. Generally, the larger the inelastic strain range, the shorter the crack life. Become. In addition, since it is "strain", it is shown by the ratio (%) of elongation to the unit length, and the strain range shows the width (range) of the value.
[0054]
In Example 1 of the present invention, the annular braking disk and the braking disk holding member employed in the first reduction gear are used. That is, as shown in FIG. 3, the annular brake disk 2 is connected by attaching the support disk 8b to the rotary shaft 1 and connecting the annular brake disk 2 to the support disk 8b via the rib 8a.
[0055]
The material of the annular braking disk is Cr-Mo low alloy steel (JIS SCM415), and the outer diameter of the rotating shaft of the vehicle is 130 mm, while the dimensions of the annular braking disk are inner diameter 240 mm x outer diameter 450 mm x thickness It was 10 mm.
[0056]
The dimensions of the support disk were 130 mm inside diameter x 450 mm outside diameter x 10 mm thickness, the rib dimensions were 240 mm inside diameter x 450 mm outside diameter x 4 mm thickness x 20 mm height, and 36 pieces were arranged on the circumferential surface of the support disk.
[0057]
In Example 2 of this invention, it was set as the structure of the cyclic | annular brake disc and brake disc holding member which are employ | adopted with a 2nd reduction gear. That is, as shown in FIG. 7, the rear braking disk 8c is connected to the annular braking disk 2 and the opposite side with the rib 8a attached to the rotating shaft 1 interposed therebetween.
[0058]
The dimensions of the annular braking disk and the rotating shaft were the same as those of Example 1 of the present invention. The dimensions of the back disk were an inner diameter of 240 mm, an outer diameter of 450 mm, and a thickness of 10 mm.
[0059]
In Example 3 of the present invention, the annular brake disc and the brake disc holding member employed in the third reduction gear are configured. That is, as shown in FIG. 8, the rib 8a attached to the rotating shaft 1 and the annular braking disk 2 are connected, and the rib 8a is configured as a fin for heat dissipation of the braking disk.
[0060]
The dimensions of the annular braking disk and the rotating shaft were the same as those of Examples 1 and 2 of the present invention. The rib dimensions were 130 mm inside diameter x 450 mm outside diameter x 4 mm thickness x 20 mm, and 36 plates were arranged on the circumferential surface of the support disk.
[0061]
In the comparative example, it was set as the structure of the disk shaped brake disk of the eddy current reduction device using a permanent magnet. That is, as shown in FIG. 1, the inner peripheral portion of the annular braking disk 21 is attached to the rotary shaft 1, and the cooling fins 9 are provided on the back surface of the braking disk 21.
[0062]
The material of the brake disk is the same as in Examples 1 to 3 of the present invention. The outer diameter of the rotating shaft of the vehicle is 130 mm, while the dimensions of the brake disk are 130 mm inner diameter × 450 mm outer diameter × 10 mm thickness. In addition, the fin dimensions were an inner diameter of 240 mm, an outer diameter of 450 mm, a thickness of 4 mm, and a height of 20 mm, and 36 pieces were arranged on the circumferential surface of the support disk.
[0063]
Table 1 shows the results of evaluating the inelastic strain range by FEM analysis using Examples 1-3 of the present invention and Comparative Examples.
[0064]
[Table 1]

From the evaluation results in Table 1, in Examples 1 to 3 of the present invention, the inelastic strain range generated on the surface of the brake disk is smaller when braking and non-braking are repeated than in the comparative example. As described above, the larger the inelastic strain range, the shorter the life until the occurrence of thermal fatigue cracks. Therefore, Examples 1-3 of the present invention can suppress the occurrence of thermal fatigue cracks compared to the comparative example, and the device It can be seen that the durability of can be improved.
[0065]
As described above, the embodiments and examples of the present invention have been illustrated and described. However, the present invention is not limited to these examples, and is within the scope of the technical idea shown in the claims. It can be changed.
[0066]
【The invention's effect】
In the eddy current reduction device of the present invention, the inner peripheral portion of the braking disk is not directly fixed to the rotating shaft, but is an annular braking disk, so that the radial width is small and the temperature difference formed in the radial direction is small. Thus, the inelastic strain generated in the brake disk is reduced, and even when the brake disk is used for a long period of time, it is possible to prevent the brake disk from being deformed to reduce the braking force or to generate thermal fatigue cracks.
[0067]
Thereby, it is excellent in the magnetic efficiency at the time of braking, it is possible to reduce the size and weight with a simple structure, and the durability and life of the device can be remarkably improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a configuration example of an eddy current reduction device that generates eddy currents in opposing conductors using a permanent magnet.
FIG. 2 is a diagram showing a cross-sectional configuration example of a first reduction gear device according to the present invention.
FIG. 3 is a diagram showing a structural example (XX view front view) of a braking disk and a braking disk holding member employed in the first reduction gear device according to the present invention.
FIG. 4 is a diagram showing a configuration in which a brake disk is connected to a support disk via ribs inclined in a rotation direction with respect to a radial straight line passing through the center of a rotation axis.
FIG. 5 is a diagram showing a configuration in which a brake disk is connected to a support disk via ribs curved in a rotation direction with respect to a radial straight line passing through the center of a rotation axis.
FIG. 6 shows that the brake disk is connected to a support disk via a rib curved in a rotational direction with respect to a radial straight line passing through the center of the rotation axis, and the rib protrudes further inward than the inner peripheral side of the brake disk. It is a figure which shows a structure.
FIGS. 7A and 7B are diagrams illustrating a configuration of a second reduction gear device according to the present invention, in which FIG. 7A shows a cross-sectional configuration example, and FIG. It is a figure shown by a visual field front view.
FIGS. 8A and 8B are diagrams illustrating a configuration of a third reduction gear according to the present invention, in which FIG. 8A shows a cross-sectional configuration example, and FIG. 8B shows a structural example of a brake disc and a brake disc holding member (ZZ It is a figure shown by a visual field front view.
[Explanation of symbols]
1: Rotating shaft 2, 21: Braking disc
3: guide tube, 3a: pole piece
4: Retaining ring, 5: Cylinder
6: Piston rod, 7: Magnet, permanent magnet
8: Braking disc holding member, 8a: Rib
8b: Support disk (support plate)
8c: Rear disc (rear plate)
9: Cooling fin

Claims (8)

An annular braking disk for generating a braking force applied to the rotating shaft of the vehicle;
A braking disk holding member attached to the rotating shaft and connected to the annular braking disk on one main surface of the annular braking disk;
A retaining ring movable in a direction approaching and away from the other main surface of the annular braking disk;
A plurality of first permanent magnets facing the other main surface of the annular braking disk in the circumferential direction of the retaining ring and having adjacent magnetic pole surfaces arranged in opposite directions;
The first permanent magnet is configured to be movable between a position where the first permanent magnet approaches the annular braking disk and enters a braking state, and a position where the first permanent magnet moves away from the annular braking disk and enters a non-braking state .
The braking disk holding member includes a plurality of ribs extending from an inner circumferential side to an outer circumferential side on the one main surface of the annular braking disk, and the adjacent ribs that are attached to the rotating shaft while holding the ribs. An eddy current reduction device comprising: a support plate that forms a cavity with the annular braking disk . An annular braking disk for generating a braking force applied to the rotating shaft of the vehicle;
A braking disk holding member attached to the rotating shaft and connected to the annular braking disk on one main surface of the annular braking disk;
A retaining ring that is held in contact with the other main surface of the annular braking disk in a non-contact manner;
A plurality of composite magnets including at least one second permanent magnet and at least one switching electromagnet are provided facing the other main surface of the annular braking disk in the circumferential direction of the retaining ring,
The direction of the magnetic pole faces of the adjacent composite magnets are arranged opposite to each other ,
The braking disk holding member includes a plurality of ribs extending from an inner circumferential side to an outer circumferential side on the one main surface of the annular braking disk, and the adjacent ribs that are attached to the rotating shaft while holding the ribs. An eddy current reduction device comprising: a support plate that forms a cavity with the annular braking disk .   The eddy current reduction device according to claim 1, further comprising a guide cylinder that accommodates the holding ring and is supported by a non-rotating portion of the vehicle.   The annular braking disk is provided at a position facing the magnetic pole surface of the first permanent magnet or the composite magnet, and the ring width is equal to or greater than the radial length with respect to the rotation axis of the first permanent magnet or the composite magnet. The eddy current reduction device according to claim 1, wherein the eddy current reduction device is provided. The eddy current reduction device according to any one of claims 1 to 4, wherein the rib protrudes further inward than the inner peripheral side of the annular braking disk . The eddy current reduction device according to claim 1, wherein the rib is configured as a heat dissipation fin of the annular braking disk . The ribs, eddy current reduction apparatus according to any one of claims 1 to 6, wherein the configured inclined in the rotational direction with respect to the radial line passing through the center of the rotary shaft. The ribs, eddy current reduction apparatus according to any one of claims 1 to 6, wherein the configured curved in the rotational direction with respect to the radial line passing through the center of the rotary shaft.

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