JP3700567B2 - ON-OFF switching device for eddy current type speed reducer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ON-OFF switching device for an eddy current type reduction gear attached to a large vehicle such as a bus or truck as a braking assist device.
[0002]
[Prior art]
In recent years, for large vehicles such as buses and trucks, for the purpose of reducing the number of times of use of foot brakes on downhill roads, preventing abnormal lining wear and fading, and shortening the braking stop distance, In addition to the foot brake, which is the main brake, and the exhaust brake, which is the auxiliary brake, eddy current speed reducers have been installed. In recent years, there have been an increasing number of eddy current reduction devices that use permanent magnets as magnetic poles and do not need to be energized during braking, as disclosed in JP-A-1-298948.
[0003]
As for the permanent magnet type eddy current type speed reducer, a single row swivel type and a double row swivel type have been devised at present.
Of these, the single-row swivel type, for example, as shown in FIG. 4, a magnet support ring 3 is attached via a bearing 4 to a support 2 made of a nonmagnetic material such as aluminum fixedly supported on a bearing case 1. A plurality of permanent magnets 6 that are pivotally supported and have a circular arc surface in a cross section perpendicular to the rotary shaft 5 are arranged at equal intervals on the outer peripheral surface of the magnet support ring 3. A plurality of switch plates 7 made of a ferromagnetic material are circumferentially arranged at equal intervals through a nonmagnetic support member so as to face the surface of each group of permanent magnets 6 attached to the magnet support ring 3. It is the structure attached to the support body 2 integrally. Then, the rotor 8 is fitted to the rotary shaft 5, and the cylindrical portion 8 a is opposed to the switch plate 7 with a predetermined gap, and the support body 2 is provided with a drive device for rotating the magnet support ring 3. Arranged above.
[0004]
Further, in the two-row swivel type, for example, as shown in FIG. 5, two magnet support rings are provided on a support body 2 made of a nonmagnetic material such as aluminum fixedly supported on a bearing case 1. Is fixedly supported by the support 2 and the other is pivotally supported via a bearing 4 so that the upper and lower magnetic pole surfaces are rotational shafts on the outer peripheral surfaces of the fixed support ring 3a and the rotation support ring 3b. A plurality of permanent magnets 6a, 6b having a circular arc surface in a cross section perpendicular to 5 are arranged at equal intervals, and the permanent magnets 6a, 6b attached to the fixed support ring 3a and the rotation support ring 3b are arranged. A plurality of switch plates 7 made of a ferromagnetic material are arranged circumferentially at equal intervals through a non-magnetic support member so as to face the surface of the group, and are integrally attached to the support 2. Then, the rotor 8 is fitted to the rotary shaft 5, and the cylindrical portion 8 a is opposed to the switch plate 7 with a predetermined gap, and the support body 2 is provided with a drive device for rotating the rotation support ring 3 b. It is arranged on the circumference.
[0005]
In such a permanent magnet type eddy current reduction device, the rotation mechanism of the magnet support ring 3 or the rotation support ring 3b is the yoke link 9 protruding from the side surface of the magnet support ring 3 or the rotation support ring 3b. There are various types such as those connected to drive sources such as hydraulic cylinders, air cylinders, electric motors, etc., but in the trucks and buses etc. that have existing compressed air sources, air cylinder drive that uses the above compressed air And a double-acting type is often used as the drive cylinder.
[0006]
By the way, the force required for driving from braking OFF to braking ON or from braking ON to braking OFF in the above-described permanent magnet type eddy current reduction gear is larger than the magnetic attractive force generated by the magnetic circuit composed of the rotor and the stator. is necessary.
[0007]
For example, in the case of the two-row swivel type, as shown in FIG. 6, the polarities of the two permanent magnets 6a and 6b on the fixed side and the rotating side facing one switch plate 7 are opposite to each other. Between the switch plate 7 and the two permanent magnets 6a and 6b opposed thereto, a magnetic circuit as shown by an arrow in FIG. 6A is configured, and a permanent magnet is formed on the inner peripheral surface of the cylindrical portion 8a of the rotor 8. From the so-called braking OFF state where the magnetic flux generated from 6a and 6b does not act, the polarity of the two permanent magnets 6a and 6b on the fixed side and the rotary side of the rotating support ring 3b facing the one switch plate 7 is the same. As shown by arrows in FIG. 7B, including the adjacent switch plate 7 and the inner peripheral surface of the cylindrical portion 8a of the rotor 8 between the circumferentially adjacent permanent magnets 6a and 6b. The position where the magnetic circuit is configured and the so-called braking ON state is reached. The required force required to rotate and then rotate the rotation support ring 3b from the brake-on state to return to the brake-off state changes depending on the movement position of the rotation support ring 3b. The maximum (F1max) is reached during the period from braking OFF to braking ON. Therefore, the cylinder needs to have a required force of F1max or more.
[0008]
[Problems to be solved by the invention]
When the eddy current type speed reducer equipped with such a double-acting air cylinder is operated frequently, the air pressure of the compressed air source is increased when the air consumption exceeds the air supply to the compressed air tank. In addition to the ON-OFF operation of the eddy current type speed reducer, the function of the parts of the vehicle where the compressed air is used is reduced, which hinders stable running of the vehicle.
[0009]
Therefore, it is necessary to provide an air tank and an air supply device having a large capacity corresponding to the compressed air consumption of the eddy current type reduction gear, which has been a factor that hinders cost increase and weight reduction of the vehicle.
[0010]
In other words, the conventional eddy current type speed reducer equipped with a double-acting air cylinder consumes a large amount of air, and it is necessary to provide a large-sized and large-capacity compressed air source, which can reduce the weight and cost of the vehicle. could not. In addition, the amount of the drive cylinder projecting outside the device is large, and sufficient consideration must be given to the mountability on the vehicle, and the cost of the drive unit in the device is high.
[0011]
The present invention has been made in view of the above-described problems, and provides an ON-OFF switching device for an eddy current reduction device that can reduce compressed air, reduce the size of the device, and reduce the cost. It is an object.
[0012]
[Means for Solving the Problems]
In order to achieve the above-described object, the ON-OFF switching device of the eddy current type speed reducer according to the present invention moves the rotation support ring or the magnet support ring to the braking OFF position by moving the piston rod of the drive cylinder. When moving from the braking ON position to the braking ON position, or from the braking ON position to the braking OFF position, the rod within the range in which the smaller one of the distances in the latter half of the stroke that moves only by magnetic attraction force is maximized. It is supposed that the exit / retreat distance is absorbed by the link member. By doing so, it is possible to save compressed air and make the device compact.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
A magnet support ring or a rotation support ring (hereinafter simply referred to as a “support ring”) is rotated from the brake OFF state to hold the brake ON state, and then the support ring is rotated from the brake ON state. According to the research and experiment conducted by the present inventors, the required force required to maintain the brake OFF state actually changes as shown in FIG. 3 depending on the moving position of the support ring. Maximum during braking ON state.
[0014]
Therefore, when the compressed air is supplied to the piston side pressure receiving chamber 10a of the cylinder 10 shown in FIG. 1 from the brake OFF state and the piston 10b is pressurized, the piston 10b moves forward in the right direction of the drawing. During this forward movement, when the position A shown in FIG. 3 is exceeded, the piston 10b is drawn to the brake ON side by the magnetic attractive force without supplying compressed air to the piston side pressure receiving chamber 10a, and the brake ON Held in position.
[0015]
In addition, when compressed air is supplied to the rod-side pressure receiving chamber 10c from the brake-on state and the piston 10b is pressurized, the piston 10b moves backward in the left direction of the paper, and at the time of the backward movement, the piston 10b returns from the position A shown in FIG. By the way, even if compressed air is not supplied to the rod side pressure receiving chamber 10c, the piston 10b is pulled to the brake OFF side by the magnetic attractive force and is held at the brake OFF position.
[0016]
That is, the present inventors show that when switching from braking OFF to braking ON, the position A shown in FIG. 3 is exceeded to the braking ON state, and when switching from braking ON to braking OFF is illustrated in FIG. It has been found that the driving force by the cylinder is unnecessary because the support ring moves only by the magnetic attraction force even if the compressed air is not supplied while returning from the A position to the brake OFF state. .
[0017]
The ON-OFF switching device of the eddy current type speed reducer according to the present invention has been made based on the above-mentioned knowledge of the present inventors, and a plurality of permanent magnets are polarized to each other on a support that is pivotally supported by a rotating shaft. A fixed support ring for a yoke and a rotating support ring that are arranged in the opposite direction are arranged in parallel, and a plurality of switch plates made of a ferromagnetic material that are magnetically insulated from each other are provided on the outer peripheral magnetic pole surface of these permanent magnet groups. Two-row swirl type eddy current type speed reducer arranged opposite to each other, or a magnet support ring for a yoke in which a plurality of permanent magnets are provided with their polarities opposite to each other on a support that is pivotally supported on a rotating shaft. A single-row swivel type eddy current reduction device in which a plurality of switch plates made of a ferromagnetic material, which are freely supported by shafts and are magnetically insulated from each other, are arranged on the outer peripheral magnetic pole surfaces of the permanent magnet groups. Supports dynamic support ring or magnet support ring In an ON-OFF switching device in which a drive cylinder is arranged via a link member to rotate a predetermined angle, the rotation support ring or the magnet support ring is braked by the withdrawal and withdrawal of the rod of the drive cylinder. When moving from the OFF position to the braking ON position, or from the braking ON position to the braking OFF position, the portion within the range in which the smaller one of the distances in the latter half of the stroke that moves only by the magnetic attractive force is maximized. The rod withdrawal / retraction distance is absorbed by the link member.
[0018]
In the ON-OFF switching device for an eddy current type speed reducer according to the present invention, the stroke ST of the driving cylinder is the distance STl from the braking OFF state to the A position shown in FIG. 3 and from the braking ON position to the A position. It is sufficient that the larger one of the distances ST2 is equal to or larger than the value obtained by adding the difference between the smaller distance and the distance of the rod of the cylinder absorbed by the link member. Accordingly, as a case where the stroke ST of the cylinder can be shortened to the maximum, the distance absorbed by the link member (hereinafter referred to as “working distance L”) when the distances STl and ST2 are equal is the distance STl (= ST2). In this case, the cylinder stroke ST is half of the rotation distance ST0 of the rotation support ring 3b or the magnet support ring 3.
[0019]
In the ON-OFF switching device of the eddy current type speed reducer according to the present invention, the working distance L is set so that the rotation support ring 3b or the magnet support ring 3 is moved by the withdrawal / retraction of the rod of the cylinder 10 as described above. When moving from the brake OFF position to the brake ON position, or when moving from the brake ON position to the brake OFF position, within the range in which the smaller one of the distances in the latter half of the stroke that is moved only by the magnetic attractive force is maximized. Thus, the opening width B of the link member 11 and the roller diameter d may be determined from the rotation distance ST0 of the rotation support ring 3b or the magnet support ring 3 and the stroke ST.
[0020]
That is, the opening width B of the link member 11 is theoretically set to B = ST0−ST + d from L = ST0−ST = Bd (see FIG. 1) when the roller diameter is d. It will be. However, even if the opening width B of the link member 11 is equal to or larger than the theoretical value obtained by the above formula, the working distance L is the smaller one of the distances in the latter half of the stroke that is moved only by the magnetic attractive force. Needless to say, there is no problem with the ON / OFF switching operation.
[0021]
In the ON / OFF switching device for an eddy current type speed reducer according to the present invention described above, the stroke of the drive cylinder may be set to be equal to or greater than the value described above. In addition, the consumption of compressed air can be reduced, and further, the apparatus can be made compact and the cost can be reduced at the same time.
[0022]
【Example】
Hereinafter, the present invention will be described based on one embodiment shown in FIGS.
FIG. 1 is a schematic configuration diagram of a main part of an ON / OFF switching device for an eddy current type reduction device according to the present invention, and FIG. 2 is a front view of the ON / OFF switching device for a two-row swirling type eddy current type reduction device according to the present invention. is there.
[0023]
1 and 2, reference numeral 10 denotes a driving cylinder to which compressed air is supplied via a control valve (not shown). In this embodiment, two cylinders are arranged at positions facing the rotation support ring 3b. Show. In the embodiment shown in FIG. 2, the cylinder 10 disposed above the paper surface in FIG. 2 is a double-acting cylinder similar to the conventional one, and the cylinder 10 disposed below the paper surface is connected to one of the air ports. Supplies compressed air, but the other air port is open to the atmosphere through a filter, for example.
[0024]
Reference numeral 11 denotes a link member attached to the tip of each piston rod 10 d of these cylinders 10, and a rotation support ring 3 b at a position facing these link members 11 has a roller supported by each link member 11. 12 is pivotally supported so that it can freely rotate.
[0025]
In the ON-OFF switching device of the eddy current type speed reducer according to the present invention, the rotation support ring 3b is moved from the brake OFF position to the brake ON position or braked by moving the piston rod 10d of the cylinder 10 back and forth. When moving from the ON position to the brake OFF position, the distance in the latter half of the stroke that is moved only by the magnetic attractive force, that is, ST2 in FIG. 3 in the case of braking OFF to braking ON, in the case of braking ON to braking OFF 3 is constructed so that the link member 11 absorbs the distance of the rod within the range in which the smaller one of ST1 in FIG.
[0026]
That is, in the ON / OFF switching device for an eddy current type speed reducer according to the present invention, the rotation support ring 3b is moved from the braking OFF position to the braking ON position or from the braking ON position to the braking OFF position. In this case, the link member 11 absorbs the range (differential distance L) in which the smaller one of the distances in the latter half of the stroke moved only by the magnetic attractive force is maximized. The opening width B of the link member 11 and the diameter d of the roller are determined from the rotation distance ST0 and the stroke ST of the rotation support ring 3b so as to be the moving distance L.
[0027]
As described above, in the ON-OFF switching device of the eddy current type speed reducer according to the present invention, the rotation support ring 3b is moved from the braking OFF position to the braking ON position or from the braking ON position to the braking OFF position. In this case, the link member 11 absorbs the range (the differential distance L) in which the smaller one of the distances in the latter half of the stroke that is moved only by the magnetic attraction force is absorbed, so that the stroke ST of the cylinder 10 is The rotation distance ST0 of the rotation support ring 3b can be made shorter, and the stroke ST of the cylinder 10 can be shortened. Accordingly, the amount of compressed air consumed can be reduced by the shortening of the stroke ST of the cylinder 10, and in addition, the apparatus can be made compact and the cost can be reduced at the same time.
[0028]
The ON-OFF switching device of the eddy current type speed reducer according to the present invention is not limited to the embodiment shown in FIG. 2, and both driving cylinders may be double-acting types, or both driving It goes without saying that both cylinders may be of single acting type. Further, only one of the driving cylinders may be applied with the configuration of the present invention. Furthermore, although the present embodiment has been described with respect to the two-row turning type, a single-row turning type may be used.
[0029]
【The invention's effect】
As described above, in the ON-OFF switching device of the eddy current type speed reducer according to the present invention, the rotation support ring or the magnet support ring is moved from the braking OFF position to the braking ON position by the withdrawal and withdrawal of the rod of the driving cylinder. Or, when moving from the braking ON position to the braking OFF position, the distance of the rod within the range in which the smaller one of the distances in the latter half of the stroke that moves only by the magnetic attraction force is maximized. Since it is constructed so as to be absorbed by the link member, the stroke of the cylinder can be shortened, and the consumption of compressed air can be saved by the shortening of the stroke of the cylinder. Compactness and cost reduction are possible at the same time.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a main part of an ON / OFF switching device of an eddy current type speed reducer according to the present invention.
FIG. 2 is a front view of an ON-OFF switching device of a two-row swirl type eddy current type speed reducer according to the present invention.
FIG. 3 is a diagram for explaining a relationship between a cylinder required force and a stroke in an ON-OFF switching device of an eddy current type reduction device discovered by the present inventors.
FIG. 4 is an explanatory view of the structure of a single-row swirl type eddy current type speed reducer.
FIG. 5 is an explanatory view of the structure of a two-row swirl type eddy current type speed reducer.
FIGS. 6A and 6B are explanatory views of a braking principle of the permanent magnet type eddy current reduction device in a braking OFF state, in which FIG. 6A is a longitudinal sectional side view, and FIG. 6B is a longitudinal sectional front view;
7A and 7B are explanatory views of a braking principle in a braking ON state of the permanent magnet type eddy current reduction device, where FIG. 7A is a longitudinal sectional side view, and FIG. 7B is a longitudinal sectional front view.
[Explanation of symbols]
3 Magnet support ring 3b Rotation support ring 10 Cylinder 11 Link member 12 Roller

Claims (2)

A fixed support ring for a yoke and a rotation support ring, in which a plurality of permanent magnets are provided with their polarities opposite to each other, are arranged in parallel on a support that is pivotally supported on a rotating shaft, and the outer peripheral magnetic pole surface of these permanent magnet groups In addition, in order to rotate the rotation support ring at a predetermined angle with respect to the support, in a two-row swing type eddy current type reduction device in which a plurality of switch plates made of ferromagnetic materials magnetically insulated from each other are arranged to face each other In addition, in the ON-OFF switching device in which the drive cylinder is arranged via the link member, the rotation support ring is moved from the brake OFF position to the brake ON position or brake ON by the withdrawal of the rod of the drive cylinder. When moving from the position to the braking OFF position, the link distance of the rod within the range in which the smaller one of the distances in the second half of the stroke that moves only by the magnetic attraction force is maximized is the link. ON-OFF switching device of the eddy current type reduction gear, characterized by being configured to absorb the wood. A magnet support ring for a yoke, in which a plurality of permanent magnets are circumferentially arranged with their polarities opposite to each other, is rotatably supported on a support that is pivotally supported on a rotating shaft, In order to rotate the magnet support ring at a predetermined angle with respect to the support body of the single row swivel type eddy current type speed reducer in which a plurality of switch plates made of ferromagnetic materials magnetically insulated from each other are arranged to face each other, In the ON-OFF switching device in which the driving cylinder is arranged via the link member, the magnet support ring is braked from the braking OFF position to the braking ON position or from the braking ON position by the withdrawal and withdrawal of the rod of the driving cylinder. When moving to the OFF position, the link member is used to determine the distance of the rod within the range in which the smaller one of the distances in the second half of the stroke that moves only by magnetic attraction is maximized. ON-OFF switching device of the eddy current type reduction gear, characterized by being configured to absorb.

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