KR100596593B1 - Electromagnetic shock absorber for vehicle - Google Patents

Abstract

The axle side tube 2 is slidably inserted inside the vehicle body side tube 1, and the motor “M” is connected to the inside of the vehicle body side tube 1, and moves together with the axle side tube 2. The ball screw nut 3 is disposed inside the axle-side tube 2, and the screw shaft 4 connected to the motor shaft "MS" is rotatably coupled to the ball screw nut 3, where the ball screw nut ( The linear movement of 3) is converted into the rotational movement of the screw shaft 4, which is transmitted to the motor shaft "MS", thereby generating an electromagnetic force for the rotation of the motor shaft "MS", which electromagnetic force of the axle-side tube It is used as a damping force to limit linear motion.

Description

Automotive Electronic Shock Absorber {ELECTROMAGNETIC SHOCK ABSORBER FOR VEHICLE}

The present invention relates to a shock absorber inserted between a vehicle body and an axle for damping vibrations from a road, and more particularly, by linearly moving a shaft force transmission member by rotatably coupling a screw shaft to a ball screw nut. To an electromagnetic shock absorber for a vehicle having a mechanism for converting the motor into a rotational motion of the motor shaft in the motor through the screw shaft, wherein the electromagnetic force caused by the rotational motion of the motor shaft is used as a damping force.

Hydraulic shock absorbers are commonly known as being inserted between the vehicle body and the vehicle axle. This hydraulic shock absorber not only improves the riding comfort of the vehicle by attenuating input of vibrations from the road, but also suspends the vehicle body.

Automotive hydraulic damping dampers provide high damping force but require oil. Thus, the electronic shock absorber requires a sealing device and also a complicated valve mechanism to prevent leakage of oil. If the oil leaks, it may not be possible to achieve the desired damping force.

Under these circumstances, new electronic shock absorbers that do not require oil, air, power sources, etc. have recently been studied, and their literature has been published (Research of Automotive Electronic Suspensions: Automotive Technology Association, Pre-edtion for Lectures). issue of Lecture), No. 4-00, 2000).

As shown in the example of FIG. 4, the basic configuration of the electromagnetic shock absorber includes a ball screw nut 87, a flange 74 holding the ball screw nut 87, and an eye bracket. A flange 77, a guide rod 76 connecting the flange 74 to the flange 77, a screw shaft 88 rotatably coupled to the ball screw nut 87, a coupling 83, A motor 89 is connected to the upper end of the screw shaft 88 via the shaft 89a.

In addition, when using this electromagnetic shock absorber as a vehicle suspension by inserting such an electromagnetic shock absorber between the vehicle body and the axle, the upper end of the electromagnetic shock absorber is connected to the vehicle body via a flange fixed to the flange 68 disposed on the motor 89. Its lower end is connected to the axle via an eye type bracket 78.

In this case, the motor 89 is connected to the flange 72 through the flange 70 and the connecting rod 71 at its lower end, the ball bearing 84 is fixed to the inner surface of the flange 72, the screw shaft An upper portion of the 88 is rotatably inserted inside the ball bearing 84.

In addition, the flange 72 is connected to the flange 75 by a connecting rod 73, the guide rod 76 is slidably inserted into the bore formed in the flange 75, so that the ball screw nut 87 Only linear motion is allowed.

According to the concept of suspension with an electronic shock absorber, for example in the linear movement of the ball screw nut 87 in the direction of the arrow "a" caused by the vibration input from the road, the linear movement of this ball screw nut 87 is a screw Guided by the screw groove 88a on the outer circumference of the shaft 88 and the balls in the ball screw nut 87, it is converted to the rotational movement of the screw shaft 88 inside the ball screw nut 87.

Accordingly, the rotational movement of the screw shaft 88 is transmitted through the coupling 83 attached to the upper end of the screw shaft 88 as the rotational movement of the shaft 89a in the direction of the arrow "b", whereby the motor 89 Induces electromotive force. When each electrode (not shown) of the motor 89 is shorted without a power source or connected to a control circuit for a given electromagnetic force, current flows in a coil inside the motor 89 caused by induced electromotive force and the motor 89 Generate electromagnetic force.

At this time, the electromagnetic force is generated in a direction opposite to the rotational direction of the shaft 89a, and torque for the rotation of the shaft 89a is generated due to the electromagnetic force, thereby limiting the rotation of the shaft 89a of the motor 89. Done.

Next, limiting the rotation of the shaft 89a will limit the rotation of the screw shaft 88, so that the torque acts as a damping force that limits the linear motion of the ball screw nut 87.

In other words, the action of torque serves as a damping force to limit the extension and contraction motion of the electromagnetic shock absorber.

Here, as shown in Fig. 5, when looking at the ball screw nut 87, a plurality of balls 87a of small diameter are arranged in the ball screw nut 87 and these balls 87a are formed of the screw shaft 88. Engaging with the helical groove 88a to form a pair of screws, the screw shaft 88 is coupled to the ball screw nut 87 and rotated about the nut.

Thus, as the ball screw nut 87 moves linearly in the axial direction, the balls move along the groove 88a, thus forcibly supplying the rotational force to the screw shaft 88 and rotating the screw shaft 88.

Therefore, since the screw shaft 88 and the ball screw nut 87 move smoothly together, it is useful as a mechanism for converting the linear motion required for the electromagnetic shock absorber into rotational motion.

As described above, the oil-free electronic shock absorber is very useful because it does not require a sealing mechanism or a complicated valve mechanism to prevent the leakage of oil, while actually causing various problems when used in the suspension as follows.

That is, since the electromagnetic shock absorber is typically disposed inclined between the vehicle body and the axle, the force acting on the shock absorber during vehicle travel is inclined as well as the axial direction as the bending force caused by vibrations or push-up inputs caused by vehicle rotation, rough roads, and the like. It may be input to the ball screw nut in the direction.

The flange 75 supports this bending force, but a slight gap between the flange 75 and the guide rod 76 or between the flange 75 and the screw shaft 88 is inevitably formed due to machining, and the flange (75) may not fully support the bending force caused by looseness as a gap between them.

Likewise, there is a looseness as a gap between the ball screw nut 87 and the screw shaft 88 generated due to machining, and there is a tendency to create a loose fit therebetween.

As a result, as a large force is input to the electromagnetic shock absorber in the oblique direction, as shown in Fig. 6, the electromagnetic shock absorber is inclined, whereby the center axis "c" of the screw shaft 88 is reduced to that of the ball screw nut 87. It may be biased from the central axis "d".

The reason is that in the electromagnetic shock absorber, the ball screw nut 87 is fitted and fixed to the upper end of the guide rod 76, so that the ball screw nut 87 is horizontal from the eye bracket 78 attached to the lower end of the guide rod 76. The rotational motion centered around the position at which the ball screw nut 87 and the screw shaft 88 engage when they are received is exerted on the ball screw nut 87. As a result, the central axis of the ball screw nut 87 inevitably deviates from the central axis of the screw shaft 88 as shown in FIG.

The ball screw nut 87 is attached to the screw shaft 88 only through the plurality of balls 87a, so that the load acts intensively on the parts of the balls 87b and 87c due to the bias of the central axis therebetween. Thus, the threads of the balls 87b and 87c or the screw shaft 88 tend to be damaged.

Next, by causing damage to the threads of the balls 87b and 87c or the screw shaft 88, the movement of the shock absorber in the direction of rotation, extension or contraction of the screw shaft 88 and the ball screw nut 87 is performed well. This will not deteriorate the operation of the electronic shock absorber, causing breakage.

Further, since the suspension spring is not attached to the above-described electromagnetic shock absorber, when the electromagnetic shock absorber is interposed between the vehicle body and the vehicle axle, the vehicle body of some vehicles to which the electromagnetic shock absorber is applied is lowered and the electromagnetic shock absorber does not act as a shock absorber. There is a case.

In view of the above problems, it is an object of the present invention to provide an electronic shock absorber which can be applied to a vehicle in which the electromagnetic shock absorber uses electromagnetic force as the damping force, that is, can generate the damping force without using oil.

In order to achieve the above object, the first aspect of the present invention is that the axle-side tube is slidably inserted outside the vehicle body side tube, the upper suspension spring receiver is attached to the vehicle body side tube, the lower suspension spring receiver is axle side It is attached to the tube, the motor is connected inside or outside the vehicle body side tube, and the ball screw nut is disposed inside the axle side tube, which ball screw nut provides an electronic shock absorber for the vehicle moving with the axle side tube. . The screw shaft, which is directly connected to the motor shaft or through a power transmission, or integrally formed with the motor shaft, is rotatably coupled to the ball screw nut, where the linear motion of the ball screw nut is converted to the rotational motion of the screw shaft to the motor shaft. Transmitted and thereby generate an electromagnetic force, the torque caused by the electromagnetic force on the rotation of the motor shaft is used as a damping force to limit the linear motion of the axle-side tube.

According to a second aspect of the present invention, the axle-side tube is slidably inserted outside the vehicle body side tube, the upper suspension spring receiver is attached to the vehicle body side tube, the lower suspension spring receiver is attached to the axle side tube, and the motor is The ball screw nut is connected inside or outside the axle side tube, and the ball screw nut is disposed inside the vehicle body side tube, and the ball screw nut provides an electronic shock absorber for the vehicle that moves with the vehicle body side tube. The screw shaft, which is directly connected to the motor shaft or through a power transmission, or integrally formed with the motor shaft, is rotatably coupled to the ball screw nut, where the linear motion of the ball screw nut is converted to the rotational motion of the screw shaft to the motor shaft. Transmitted and thereby generate an electromagnetic force, the torque caused by the electromagnetic force on the rotation of the motor shaft is used as a damping force to limit the linear movement of the tube on the vehicle body side.

Accordingly, the vehicle electromagnetic shock absorber according to the first or second aspect of the present invention uses the electromagnetic force generated in the motor as the damping force, and can generate the damping force without using oil.

Further, since the axle-side tube is slidably inserted into the vehicle body-side tube, the inclination of the axle-side tube toward the vehicle body-side tube is prevented even when the bending force is exerted on the vehicle electromagnetic shock absorber. As a result, the central axis of the ball screw nut is not biased from the central axis of the screw shaft, thereby avoiding damage of the ball screw nut and the screw shaft, that is, the vehicle electronic shock absorber.

Further, according to the electromagnetic shock absorber, when the motor is connected inside the vehicle body side tube, since important elements of the vehicle electromagnetic shock absorber such as the motor, the ball screw nut and the screw shaft are covered by the axle side tube and the vehicle body side tube, Thus, when applied to a vehicle, rainwater, mud, stones, etc. do not enter the electronic shock absorber or hit the key elements directly. Damage to the electronic shock absorber for the vehicle due to rain water, mud, stones, etc. can be effectively prevented.

In addition, since the suspension spring receiver is disposed in the vehicle electromagnetic shock absorber, the suspension spring can be attached to the electromagnetic shock absorber. Thus, when inserted between the vehicle body and the axle, this spring acts as a shock absorber and can be applied to various vehicles.

Thus, an electronic shock absorber without oil can be applied to a vehicle based on using an electromagnetic force as a damping force due to the above-described effect.

According to a third aspect of the present invention, the axle-side tube is slidably inserted outside the vehicle body side tube, the upper suspension spring receiver is attached to the vehicle body side tube, the lower suspension spring receiver is attached to the axle side tube, and the coil is It is wound around a shaft rotatably inserted inside the vehicle body side tube, and a permanent magnet is disposed opposite the coil on the vehicle body side tube to generate a magnetic field inside the vehicle body side tube, and the ball screw nut is also the axle side tube. The ball screw nut, which is disposed inside, moves with the axle side tube to provide an electronic shock absorber for the vehicle. The screw shaft connected to the shaft directly or through a power transmission or integrally formed with the shaft is rotatably coupled to the ball screw nut, where the linear motion of the ball screw nut is converted to the rotational motion of the screw shaft and transmitted to the shaft. This generates an electromagnetic force and the torque caused by the electromagnetic force with respect to the rotation of the shaft is used as a damping force to limit the linear motion of the axle-side tube.

According to a fourth aspect of the present invention, the axle-side tube is slidably inserted outside the vehicle body side tube, the upper suspension spring receiver is attached to the vehicle body side tube, the lower suspension spring receiver is attached to the axle side tube, and the coil is It is wound around a shaft rotatably inserted inside the axle side tube, and a permanent magnet is disposed opposite the coil in the axle side tube to generate a magnetic field inside the axle side tube, and the ball screw nut is inside the vehicle body side tube. This ball screw nut is arranged to provide an electronic shock absorber for a vehicle that moves with the vehicle body side tube. The screw shaft connected to the shaft directly or through a power transmission or integrally formed with the shaft is rotatably coupled to the ball screw nut, where the linear motion of the ball screw nut is converted to the rotational motion of the screw shaft and transmitted to the shaft. This generates an electromagnetic force and the torque caused by the electromagnetic force with respect to the rotation of the shaft is used as a damping force to limit the linear movement of the tube on the vehicle body side.

Thus, in the vehicle electromagnetic shock absorber of the third or fourth aspect of the present invention, electromagnetic force is generated in the coil, and torque based on electromagnetic force with respect to the rotation of the shaft is a damping force that limits the linear motion of the vehicle body side tube or the axle side tube. It can be used as. Thus, such electron buffers can also achieve the same effects as the first or second aspect of the present invention.

Moreover, the coil or permanent magnet is attached directly inside the vehicle body side tube or the axle side tube and does not require the frame to cover the coil or permanent magnet. Therefore, as compared with the arrangement in which the motor is arranged inside the vehicle body side tube or the axle side tube, the heat generated by the coil does not remain inside the vehicle body side tube or the axle side tube.

Further, even though heat generated by the coil is transferred to the vehicle body side tube or the axle side tube, this heat can be effectively released by the vehicle body side tube or the axle side tube.

Thus, an increase in temperature of the coil itself can be avoided, so that the insulation performance of the wire forming the coil does not deteriorate due to chemical changes in the insulation coating of the wire.

As a result, leakage of the coil is prevented and damage to the vehicle electronic shock absorber is limited.

Thus, the electronic shock absorber without oil can be applied to the vehicle based on using the electromagnetic force as the damping force due to the above-described effect.

In a preferred mode of the first or third aspect of the invention, the ball screw nut is connected to one end of the connecting pipe inserted inside the vehicle body side tube and the other end thereof to the axle side tube.

Further, in the preferred mode of the second or fourth aspect of the present invention, the ball screw nut is connected to one end of the connecting pipe inserted inside the axle-side tube and the other end is connected to the vehicle body-side tube.

In this preferred mode, the connecting pipe is arranged inside the vehicle body side tube or the axle side tube and the ball screw nut is connected directly to the connection pipe without connection to the vehicle body side tube or the axle side tube, so that the stone hits the electronic shock absorber. Even if the same up and down oscillation occurs, the ball screw nut can be protected.

In addition, if a connecting pipe shorter than the vehicle body side tube or the axle side tube is used, the connection pipe connected to the ball screw nut is compared with the case where the ball screw nut is connected to the middle of the vehicle body side tube or the axle side tube. Only by inserting the inside the vehicle body side tube or the axle side tube, the ball screw nut can be disposed in the middle of the vehicle body side tube or the axle side tube, thereby providing easy processing of the nut.

Moreover, in another preferred mode of the first or third aspect of the present invention, the anti-rotation device is arranged so that the vehicle body side tube does not rotate with respect to the ball screw nut.

Moreover, in another preferred mode of the second or fourth aspect of the invention, the anti-rotation device is arranged so that the axle-side tube does not rotate relative to the ball screw nut.

Thus, in the electromagnetic shock absorber of the preferred mode, the vehicle body is particularly used as the strut type and when the vehicle body side tube or the axle side tube is not rotated with respect to the ball screw nut when mounted on the vehicle body, the vehicle body The ball screw nut moving with the side tube or the axle side tube rotates when the vehicle rotates, and this rotational movement is then transmitted to the motor shaft or shaft. This prevents electromagnetic forces from generating in the motor or coil to produce damping forces or the ball screw nut rotates for each vehicle rotation to move the screw shaft linearly to change the vehicle height to increase or decrease.

Also in another preferred aspect of the first or third aspect, the vehicle mounting portion has an upper suspension spring receiver connected between the vehicle body side tube and the motor, the suspension spring being inserted between the upper suspension spring receiver and the lower suspension spring receiver. .

In this preferred mode, since the motor is arranged inside the vehicle body formed by the car body to prevent rain, mud or stones from hitting the motor directly, breakage of the motor caused by this point can be avoided.

In addition, the vehicle electronic shock absorber can have sufficient stroke as the shock absorber because the motor length is not added as the length of the shock absorber itself.

In addition, such a vehicle electronic shock absorber is provided with a suspension spring can act as a shock absorber between the vehicle body and the axle and can be applied to various vehicles.

Furthermore, in a preferred mode of the first, second, third or fourth aspect, the vehicle mounting portion has an upper suspension spring receiver connected to the tip of the motor or the tube of the vehicle body side, and the suspension spring includes the upper suspension spring receiver and the lower suspension. It is inserted between the spring receivers.

Therefore, such an electronic shock absorber for a vehicle can act as a shock absorber between the vehicle body and the axle because the suspension spring is provided, and can be applied to various vehicles.

Furthermore, in a preferred mode of the first, second, third or fourth aspect, the vehicle mount comprises a bracket connectable to the vehicle, a bush held by and enclosed by the bracket, and a rolling bearing retained and enclosed by the bush. Wherein the upper suspension spring receiver is attached to the bracket and the vehicle body side tube or motor is fitted to the inner surface of the rolling bearing.

In this preferred mode, in particular when such a vehicle electromagnetic shock absorber is used as the strut type and mounted on the vehicle body, the electromagnetic shock absorber itself is rotatable relative to the vehicle body when the vehicle rotates, whereby the axle side to the vehicle body side tube is Limit the rotation of the tube. As a result, the ball screw nut rotates and this rotational motion is then transmitted to the motor shaft or shaft. This prevents the electromagnetic force from being generated in the motor or coil to produce damping forces or the ball screw nut rotates for each vehicle rotation to move the screw shaft linearly to change the vehicle height to increase or decrease.

These and other objects, features, aspects, and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which discloses a preferred embodiment of the present invention in connection with the accompanying drawings.

Preferred Embodiments of the Invention

Selected embodiments of the present invention will now be described with reference to the drawings. It will be apparent to those skilled in the art that the following description of the embodiments of the present invention is provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

First embodiment

The vehicle electronic shock absorber of the first embodiment according to the present invention is slidably inserted into the outer tube 2 through the outer tube 2, the bearing members 9, 10, which are the axle-side tubes, as shown in FIG. An inner tube 1 which is a vehicle body side tube to be connected, a connecting pipe 5 coaxially connected inside the outer tube 2, a motor “M” connected to an upper end of the inner tube 1, and having a shorted electrode; Ball screw nut (3) connected to the upper end of the connecting pipe (5), screw shaft (4) connected to the motor shaft "MS" of the motor "M" inside the frame of the motor "M", of the outer tube (2) A vehicle mounting portion “T” equipped with a lower suspension spring receiver 6 fixed to the circumferential side, an upper suspension spring receiver 7 attached to a shaft 13 disposed on the motor “M” via a nut 19 and Interposed between the upper suspension spring receiver (7) and the lower suspension spring receiver (6) Includes a suspension spring (8), it consists of a strut type as shown in FIG.

As will be explained in detail below, the outer tube 2 has a lower end which is cylindrical and sealed by a cap "C". An axle bracket 14 connected to the axle side is arranged on the lower side of the outer tube 2 and the lower suspension spring receiver 6 is fixed to the circumferential side of the outer tube 2.

The inner tube 1 is cylindrical and the motor "M" is connected at the upper end of the inner tube 1 and the spring seat 21 with the cushion spring 20 is fitted to the lower end of the inner tube 1 and the outer It is slidably inserted inside the tube 2. Lip “R” is disposed at the open end of the outer tube 2 and slides with the inner tube 1. Therefore, rainwater, dust, and the like do not flow into the vehicle electronic shock absorber.

And the key 1a is disposed on the outer surface of the inner tube 1 at its lower end and the key groove (not shown) is disposed along the axial direction on the inner surface of the outer tube 2. The key 1a is engaged with the key groove so that the outer tube 2 does not rotate relative to the inner tube 1.

However, the key 1a and the key groove are arranged to prevent the inner tube 1 from rotating with respect to the ball screw nut 3 described later. That is, the ball screw nut 3 is arranged at the tip end of the connecting pipe 5 which is connected to the outer tube 2, so that the inner tube 1 is a ball screw due to the relationship between the key 1a and the key groove. It does not rotate relative to the nut 3. Instead of arranging the key 1a and the key groove between the inner tube 1 and the outer tube 2, the key 1a and the key groove are formed on the outer surface of the connecting pipe 5 and the inner tube 1. It may be arranged between the inner surface or between the outer surface of the ball screw nut 3 and the inner surface of the inner tube 1, and also the prevention of rotation of the inner tube 1 with respect to the outer tube 2 is a key and a key groove. It may also be implemented by a different configuration than.

As described above, the inner tube 1 and the outer tube 2 are in sliding contact with each other through the bearing members 9 and 10, so that when the bending force is exerted on the vehicle electronic shock absorber, the outer tube 2 is It does not tilt with respect to the inner tube 1.

In addition to the cushion 23 in contact with the cap "C", a connecting pipe 5 screwed into the cap "C" coaxially with the outer tube 2 is arranged inside the outer tube 2. When the vehicle electronic shock absorber is fully retracted, the cushion 23 absorbs the up-and-down fluctuations generated between the spring seat 21 disposed at the lower end of the inner tube 1 and the cap "C", and also protects the electronic shock absorber. The interference with the motor "M" connected to the upper side of the inner tube 1 of the ball screw nut 3 to be described later is prevented. On the other hand, the ball screw nut 3 is protected in such a way that the cushion spring 20 described above comes into contact with the ball screw nut 3 when the vehicle electromagnetic shock absorber is fully extended.

The connecting pipe 5 is cylindrical and has a top end to which the ball screw nut 3 is connected as described above, as well as a cap disposed at the lower end of the outer tube 2, which is inserted into the inner tube 1. It has a lower end that is screwed inside the C ″. Thus, the connecting pipe 5 moves with the outer tube 2.

Next, the motor "M" connected to the upward side of the inner tube 1 will be described. The motor "M" is a cylindrical frame as a yoke (not shown), a permanent magnet attached to the frame to generate a magnetic field inside the frame, a motor shaft "MS" rotatably inserted into the frame through a bearing, and a motor shaft "MS A coil wound at a position opposite the permanent magnet in the " phase, a rectifier disposed on the outer surface of the motor shaft " MS ", and a brush attached to the brush holder. The motor "M" is well known and is connected to the upper end of the inner tube 1.

The motor "M" in this embodiment is a direct current motor, but may also be a variety of motors, such as brushless motors, alternating current motors, and motors with direct current brushes and other induction motors. Each electrode of the motor "M" is shorted or connected to a control device.

The screw shaft 4 is not only rotatably inserted into the inner tube 1 via the bearings 11 and 12, but also screwed into the motor shaft "MS" of the motor "M" at its upper end. The cushion 22 is disposed at the leading end of the lower end of the screw shaft 4 whose spiral groove (not shown) is screwed into the ball screw nut 3. As the ball screw nut 3 moves to the lower end of the screw shaft 4, i.e. when the vehicle electronic shock absorber is fully extended, the cushion 22 is used to prevent damage to the ball screw nut 3, Not only does the vertical swing caused by the interference with the cushion 22 of (3) be alleviated, but the ball screw nut 3 is prevented from slipping out of the screw shaft 4.

In the present embodiment, the upper end of the screw shaft 4 is screwed and connected inside the motor shaft "MS", but as long as the rotational movement of the screw shaft 4 is transmitted to the motor shaft "MS", the connection method is Not limited to the threaded method, other conventional methods may be used. For example, the screw shaft 4 and the motor shaft "MS" may be integrally molded.

Alternatively, a power transmission device may be arranged between the screw shaft 4 and the motor shaft "MS", thereby transmitting the rotational movement of the screw shaft 4 to the motor shaft "MS". In this case, as a power transmission device (not shown), the gear is disposed at the tip end of the motor shaft "MS" so that the gear becomes a sun gear, and the planetary gear is disposed in the screw shaft 4, and the sun gear of the inner tube 1 It is disposed on the inner surface. That is, the gear mechanism may be configured such that the planetary gear is interposed between the sun gear in the motor shaft " MS " and the sun gear in the inner tube 1 and the respective gears are coupled to each other. Alternatively, a torsion bar may also be used between the motor shaft "MS" and the screw shaft 4.

As described above, in the case where the gear mechanism is used as the power transmission mechanism, the rotation speed of the gear shaft "MS" increases or decreases with respect to the rotation speed of the screw shaft 4 based on the gear ratio of each gear. . In the case of using a torsion bar, the torsion bar absorbs to some extent the rotational speed of the screw shaft 4. Therefore, in particular, when the rotational speed of the screw shaft 4 changes, the variation can be propagated appropriately delayed to the motor shaft "MS".

For the ball screw nut 3, the structure thereof is not shown in the drawings, but for example, the helical ball retaining portion is formed on the inner surface of the ball screw nut to engage with the helical screw groove of the screw shaft and a number of balls are retained. Is placed in the department. A passage communicating between both ends of the helical ball retainer is disposed inside the ball screw nut such that the ball circulates therein. If the ball screw shaft is screwed inside the ball screw nut, and the balls in the ball screw nut are engaged with the helical screw groove of the screw shaft, as a result of the rotational movement of the screw shaft, the ball itself will rub against the screw groove of the screw shaft. Rotation due to WHEREIN enables a smoother movement compared to the rack and pinion mechanism or the like.

As described above, the ball screw nut 3 comprises a screw shaft along a helical groove in which the ball in the ball screw nut 3 travels up or down as the ball screw nut 3 linearly moves up or down. 4) is rotatably attached. At this point, the screw shaft 4 is forcibly rotated because the ball moves along the helical screw groove of the screw shaft 4.

That is, the linear motion of the ball screw nut 3 is converted to the rotational motion of the screw shaft 4 by the mechanism described above. Thus, since the ball screw nut 3 moves integrally with the outer tube 2 via the connecting pipe 5, the linear movement of the outer tube 2 is converted into the rotational movement of the screw shaft 4.

The vehicle mounting portion "T" includes a pair of up brackets 17 and down brackets 18 connectable to the vehicle, an upper suspension spring receiver 7 attached to the brackets 18, a pair of brackets 17, 18 Bush 15 held and enclosed by a shaft, and the shaft 13 disposed at the upper end of the motor "M" is held and enclosed by a bush fitted into an inner surface of the rolling bearing 16. It includes.

The brackets 17 and 18 are formed in a disk shape having recesses on their inner surfaces so as to hold and surround the bush 15 individually, and a plurality of bores (near the circumferential portions into which bolts screwed into the vehicle body are inserted). Not shown).

The bush 15 is held and enclosed by the recesses of the brackets 17 and 18 and the rolling bearing 16 is held by the notch formed in the inner surface of the bush 15. The vehicle mount "T" is fixed to the shaft 13 by a nut 19, while the shaft 13 is engaged with the inner surface of the rolling bearing 16. As a result, the vehicle electronic shock absorber is rotatable relative to the vehicle mount "T".

According to the above configuration, however, in the vehicle electronic shock absorber, the key element such as the ball screw nut 3 or the screw shaft 4 is covered by the inner tube 1 and the outer tube 2 when applied to the vehicle. Therefore, rainwater, mud, stones, etc. do not flow into the vehicle electronic shock absorber and do not directly hit the preceding key element. Therefore, the damage of the electron buffer caused by the above is effectively avoided.

In addition, since the upper and lower suspension spring receivers are disposed in the vehicle electronic shock absorbers and the suspension springs are interposed between the suspension spring receivers, even when the electronic shock absorbers are interposed between the vehicle body and the axle, It can be applied to various vehicles.

However, the basic mode of the vehicle electronic shock absorber as shown in Fig. 1 is a so-called upright electronic shock absorber in which an inner tube to which a motor is connected is attached to the vehicle body and an outer tube is attached to the axle, but the vehicle body side tube is an outer tube. The axle-side tube is an inner tube and may also be inverted in which the motor can be connected to the outer tube as an axle-side tube rather than an inner tube as the vehicle body side tube.

In addition, as shown in the figure, the motor "M" is connected to the upper end of the inner tube 1, but may also be connected to the inner tube 1, and here, as well as the ball screw nut 3 and the screw shaft 4. In addition, since the motor "M" is also covered by the inner tube 1 and the outer tube 2, even when applied to a vehicle, rainwater, mud or stones do not flow into the vehicle electronic shock absorber and directly drive the motor "M". Don't hit Thus, damage to the electron buffer caused by the above is avoided more effectively.

In addition, in the case where the motor "M" is connected to the outer tube 2 (not shown), the ball screw nut 3 may be directly connected to the inner tube 1 without the connecting pipe 5. And when a connecting pipe 5 shorter than the inner tube 1 is used here, compared to the case where the ball screw nut 3 is connected to the middle of the inner tube 1, the ball screw nut 3 By inserting the connecting pipe 5 connected to this ball screw nut 3 only inside the inner tube 1, it can be positioned in the middle of the inner tube 1, thus providing their easy machining. .

The operation will be described below. In the vehicle electronic shock absorber, the inner tube 1 is attached to the vehicle body of the vehicle via the vehicle mount "T" and the outer tube 2 is attached to the axle via the shaft bracket 14 so that pushing input or vibration is applied to the vehicle. As it is input from a road or the like during driving, the electronic shock absorber is extended or contracted.

That is, the outer tube 2 moves linearly along the outer surface of the inner tube 1. Subsequently, the ball screw nut 3, which is connected to the front end of the connecting pipe 5 connected to the outer tube 2, also moves linearly, so that the linear motion of the ball screw nut 3 is carried out as described above. It is converted into the rotational motion of, and finally transferred to the motor shaft "MS" of the motor "M".

In the case where the power transmission device is disposed between the screw shaft 4 and the motor shaft "MS" and the power transmission device is a planetary gear, the rotational speed of the motor shaft "MS" of the motor "M" is dependent on the gear ratio of the planetary gear. Accordingly it increases or decreases more than the rotational speed of the screw shaft 4.

Thus, as the motor shaft "MS" of the motor "M" rotates, the coil wound around the motor shaft "MS" traverses the magnetic flux generated by the permanent magnet attached to the frame of the motor "M", thereby inducing electromotive force. Create Then, when each electrode of the motor "M" is short-circuited, that is, the coil is short-circuited, current flows in the coil due to the induced electromotive force, producing an electromagnetic force, i.e., torque for rotation of the motor shaft "MS".

As a result, the torque for the rotation of the motor shaft "MS" limits the rotational movement of the motor shaft "MS". Thus, the rotation of the screw shaft 4 is limited by limiting the rotation of the motor shaft "MS", as a result of which the linear motion of the ball screw nut 3 and finally the ball screw nut 3 is via the connecting pipe 5. The linear movement of the outer tube 2 to be connected is limited. Thus, the torque for the rotation of the motor shaft "MS" due to the electromagnetic force acts as a damping force.

As described above, in the vehicle electronic shock absorber, the linear movement of the outer tube 2 upward and downward relative to the inner tube 1 is converted into the rotational movement of the screw shaft 4, and then the motor shaft "MS". To generate the rotational motion of. The electromagnetic force is thereby generated in the motor "M" and used as a damping force. In the present embodiment, since the strut type electromagnetic shock absorber is used, the rolling bearing 16 can be disposed in the vehicle mount "T" and the vehicle electromagnetic shock absorber can rotate with respect to the vehicle mount "T".

The electronic shock absorber then rotates relative to the vehicle mount "T" during rotation of the vehicle, but the electronic shock absorber itself can also rotate relative to the vehicle body. As a result, the rotation of the outer tube 2 relative to the inner tube 1 is limited and the ball screw nut 3 rotates. This rotation of the ball screw nut 3 is transmitted to the motor shaft or shaft. Thus, the damping force by the electromagnetic force generated in the motor or the coil is prevented from being generated or the vehicle height is changed by the linear movement of the screw shaft caused by the rotation of the ball screw nut with respect to the rotation of all the vehicles.

In addition, a key 1a is disposed in the inner tube 1, and a key groove is formed in the inner surface of the outer tube 2, so that the outer tube 2 also does not rotate relative to the inner tube 1. As a result, the ball screw nut 3 also does not rotate relative to the inner tube 1. That is, the problem in the rotation of the vehicle is limited due to the total electromagnetic shock absorber for the vehicle rotating on the rolling bearing 16, and the aforementioned problem is more effectively avoided as the key 1a and the key groove.

In addition, in the strut type electromagnetic shock absorber, the above problem is very effectively prevented, and similar effects are also obtained when the electronic shock absorber is applied when the ball screw nut and the vehicle body side tube or the axle side tube rotate and the problem is likely to occur. It goes without saying that it can be obtained.

Further, in the foregoing description, the torque for the rotation of the motor shaft "MS" is generated by shorting each electrode of each motor "M". However, for example, the motor "M" is connected to an electrical circuit whose internal resistance changes with the magnitude of the induced electromotive force, and the amount of current flowing in the motor "M" due to the induced electromotive force is changed by this electrical circuit. May be By doing so, the current flowing in the motor " M " can be changed, and then the damping force generated in the vehicle electronic shock absorber can also be changed.

In the case where the motor "M" is connected to the control device, since a predetermined damping force can be obtained by changing the amount of current flowing in the motor "M", it is necessary to supply current from the control device to the motor "M" from the control device to the positron. And only supplying the power required to operate the control device. Therefore, power economy is improved.

Here, as described above, the bearing members 9 and 10 are disposed between the inner tube 1 and the outer tube 2 and supported upward and downward at two points, so that the bending force is the rotation of the vehicle when the vehicle is driven, Even when applied on the vehicle electromagnetic shock absorber in an oblique direction due to a bumpy road or the like, the outer tube 2 is used to prevent the center axis of the screw shaft 4 from being biased from the center axis of the ball screw nut 3. It does not tilt with respect to the inner tube 1.

That is, because the individual central axes of the screw shaft and the ball screw nut are matched, no load is concentrated and applied to a portion of the balls of the ball screw nut, thereby avoiding ball or thread damage.

In addition, since the damage of the ball or the thread is prevented, the movement of the electronic shock absorber for the vehicle in the direction of rotation or extension and contraction of the screw shaft relative to the ball screw nut is smoothly performed.

Therefore, the operation of the vehicle electronic shock absorber is not damaged due to maintaining each smooth operation, and as a result, breakage is prevented.

In addition, as described above, when the power transmission device is arranged and used as a gear mechanism such as a planetary gear, the rotational speed of the motor shaft "MS" of the motor "M" increases more than the rotational speed of the screw shaft 4 or It is possible to reduce, so that a certain damping force can be generated by an appropriate combination of gear ratios of each gear. However, conventional devices such as planetary gears and other friction wheels may be used as the power transmission device.

That is, when the electronic shock absorber is applied to the vehicle reliably, if the gear ratio of each gear is appropriately selected, the specification of the motor "M" is changed based on the vehicle model to which the required damping force is applied corresponding to the applied vehicle model. Can be obtained without.

In addition, since the damping force can be changed in correspondence with the gear ratio, when a large damping force is required, it is not necessary to enlarge the motor "M" used for the vehicle electronic shock absorber. Thus, the cost can be reduced.

In addition, in the case of using a torsion bar as a power transmission device, when the rotational speed of the screw shaft is caused by a change in the elongation or contraction speed of the vehicle electromagnetic shock absorber, the change is appropriately delayed and transmitted to the motor shaft. Can be. That is, the moment of inertia of the motor rotor may be generated with a time delay after the extension and contraction start time or after the extension or contraction rate change. Here, the moment of inertia of the motor rotor acts to limit the rotational motion of the screw shaft, so that the vehicle electromagnetic shock absorber produces a damping force. As a result, the moment of inertia of the motor rotor in the initial period of change of the elongation and contraction speed of the electronic shock absorber generated before the generation of the time delay of the damping force due to the moment of inertia of the motor rotor and the generation of the damping force due to the electromagnetic force. The damping force caused by can be reduced.

Thus, various problems such as difficulty in controlling the damping force generated by the moment of inertia of the rotor described above can be reduced as much as possible, and the inertia of the motor rotor in the initial period of extension and contraction speed change of the vehicle electronic shock absorber. The generation of damping forces caused by moments can be reduced. As a result, when the vehicle electronic shock absorber is applied to the vehicle, the deterioration of the riding comfort in the vehicle can be avoided.

The second embodiment will be described as follows with reference to FIG. The same elements as those of the above-described embodiments are not described in detail, and only reference numerals are given.

As shown in Fig. 2, in the second embodiment, the tube bracket 26 connecting the motor bracket 25 to the motor " M " is connected to the upper end of the inner tube 1, which is the vehicle body tube, and the electronic shock absorber for the vehicle. Is configured to be attached to the vehicle mount "T" by sandwiching the rolling bearing 16 of the vehicle mount "T" between the tube bracket 26 and the motor bracket 25. However, the vehicle electronic shock absorber, the vehicle mounting portion "T" and the motor "M" are the same as in the above-described embodiment.

The tube bracket 26 is cylindrical and is connected to the inner tube 1 at its lower end and is formed disposed on a step for sandwiching the rolling bearing 16 around the circumference of the middle part.

The motor bracket 25 is cylindrical with a diameter enlarged from the upward side, and the tube bracket 26 is fitted to the lower and inner surfaces thereof so that the rolling bearing 16 is between the lower end thereof and the stepped portion of the tube bracket 26. Insert in.

A connecting shaft 27 connected to the upper end of the screw shaft 4 is inserted into the inner surface of the tube bracket 26 and the motor bracket 25 is screwed at the upper end into the motor shaft "MS" of the motor "M". The motor bracket 25 is fixed to the tube bracket 26 by a nut 28 screwed on the upper side of the connecting shaft 27.

Here, the individual brackets 25, 26 take the same shape as described above, but once the screw shaft 4 is rotatably connected to the motor shaft "MS" and the vehicle electromagnetic shock absorber is attached to the rolling bearing 16, It may be made in a shape.

However, the connecting shaft 27 connected to the upper end of the screw shaft 4 is screwed and connected to the motor shaft "MS" by screwing, and the connecting method is not limited to screw tightening, and the screw shaft Other conventional methods may be used as long as the rotational motion of (4) is transferred to the motor shaft "MS". In addition, the screw shaft 4, the connecting shaft 27 and the motor shaft "MS" may be integrally molded in the same manner as in the above-described embodiment.

In connection with the operation, as in the embodiment described above, the ball screw nut is moved up or down by extension and contraction of the vehicle electronic shock absorber, based on the rotation of the motor shaft "MS" connected to the screw shaft 4. It causes the rotational movement of the screw shaft 4, which is limited by the electromagnetic force in the generated motor "M". As a result, extension and contraction of the vehicle electronic shock absorber is limited. That is, the damping force can be generated. Thus, the same effect as that of the above-described embodiment can be obtained.

In addition, the motor "M" is located inside the vehicle body which is disposed over the vehicle attachment portion "T" and formed by the vehicle body. Thus, rain water, mud or stones can be avoided from hitting the motor directly, thereby effectively preventing the motor from being damaged.

In such a configuration, consideration of the motor length is unnecessary in designing an electronic shock absorber for a vehicle, and the stroke of the electronic shock absorber required for the shock absorber of the applied vehicle can be obtained sufficiently.

Finally, the third embodiment shown in FIG. 3 will be described. 3 shows permanent magnets 31a and 31b attached inside the inner tube 1 to generate a magnetic field inside the inner tube 1, bearings 37 inside the inner tube 1. On the outer periphery of the shaft " S ", the coil 32 wound on the shaft " S " at a position opposite the permanent magnets 31a and 31b, Rectifier 33 and a brush 34 attached to a brush holder (not shown). The inner tube 1 thus functions as a yoke and the other elements of the third embodiment are the same as those of the first embodiment described above.

The brush 34 is connected to the wire 36 via a brush holder and includes two conductors (not shown) which are individually connected to the brush 34, the leading end of which is shorted. Here, the wires 36 do not need to be shorted outside the inner tube 1 and the brushes 34 may be shorted to each other inside the inner tube 1.

However, although a single brush 34 is shown in FIG. 3, in fact a pair of brushes 34 are arranged, configured to individually contact the rectifier 33 and the coil 32 is connected to the rectifier 33. Thus, the coil 32 generates an induced electromotive force across the magnetic field generated in the permanent magnets 31a and 31b upon rotation of the shaft " S ". A current flows in the coil 32 to generate an electromagnetic force due to the short circuit of the coil 32 through the rectifier 33, the brush 34 and the wires 36.

In the third embodiment, the shaft " S " rotates due to the elongation and contraction of the vehicle electromagnetic shock absorber and the current caused by the induced electromotive force flows in the coil, thereby enabling the generation of electromagnetic force. Therefore, the same effect of the third embodiment as that of the above-described embodiment can be performed, and furthermore, the coil 32 or the permanent magnets 31a and 31b are directly attached to the inside of the inner tube 1 to cover and protect them. Needless to say, there is no need to place it. As a result, compared with disposing the motor inside the inner tube 1, the heat generated by the coil 32 is prevented from being caught inside the inner tube 1.

The heat generated by the coil 32 is transferred to the inner tube 1, but this heat can be effectively dissipated through the inner tube 1.

Thus, an increase in temperature of the coil itself can be avoided and degradation of insulation performance caused by chemical change in the insulating coating of the conductor forming the coil can be prevented.

Next, leakage of the coil is prevented and damage to the vehicle electronic shock absorber is limited. However, in the present embodiment, while the strut type vehicle electronic shock absorber has been described, it is apparent that the present invention is designed to provide an electronic shock absorber that can be applied to a vehicle, and thus the present invention can be implemented with an electronic shock absorber that is not a strut type. .

As mentioned above, according to the present invention, the electromagnetic force generated in the motor is used as a damping force, that is, the damping force can be generated without using any special oil.

Since the axial side tube is slidably inserted into the vehicle body side tube, the inclination of the axial side tube toward the vehicle body side tube is prevented even when a bending force is applied on the vehicle electromagnetic shock absorber. As a result, the central axis of the ball screw nut does not deviate from the central axis of the screw shaft, so that damage to the ball screw nut and the screw shaft is avoided.

In addition, when the motor is connected inside the vehicle body side tube, the key elements of the electronic shock absorber for the vehicle, such as the motor, the ball screw nut and the screw shaft, are covered by the axial side tube and the vehicle body side tube and thus are applied to the vehicle. In this case, damage to the electronic shock absorber for the vehicle by rainwater, mud and stones can be effectively prevented.

In addition, since the suspension spring receiver is disposed in the vehicle electronic shock absorber, when inserted between the vehicle body and the axle, it can act as a shock absorber and be applied to various vehicles.

In addition, when a planetary gear is used as the power transmission device, a predetermined damping force can be obtained by proper combination of gear ratios of the individual gears. However, as the power transmission device, conventional devices such as friction wheels except planetary gears may be used.

Thus, a predetermined damping force corresponding to the applied vehicle can be obtained without changing the specification of the motor.

If a large damping force is required, it is not necessary to increase the size of the motor used in the electromagnetic shock absorber because the damping force can be changed based on the gear ratio.

In addition, in the case of using a torsion bar as the power transmission device, the moment of inertia of the motor rotor may be generated with a time delay after the extension and contraction start time of the electronic shock absorber or after the change of the extension or contraction speed. As a result, the damping force caused by the moment of inertia of the motor rotor can be reduced in the initial period of the change of the elongation and contraction speed of the vehicular electromagnetic shock absorber generated before the generation of the damping force due to the electromagnetic force.

Therefore, various problems, such as difficulty in controlling the damping force generated by the moment of inertia of the rotor described above, can be reduced as much as possible, and the inertia of the motor rotor in the initial period of change of the elongation and contraction speed of the vehicle electronic shock absorber can be reduced as much as possible. The generation of damping forces caused by moments can be reduced. As a result, when the vehicle electronic shock absorber is applied to the vehicle, the deterioration of the riding comfort in the vehicle can be avoided.

Furthermore, when the coil or permanent magnet is directly attached inside the vehicle body side tube or the axle side tube, no frame for covering it is required. Therefore, compared with the arrangement in which the motor is disposed inside the vehicle body side tube or the axle side tube, the heat generated by the coil does not remain inside thereof.

Also, the heat generated by the coil is transferred to the vehicle body side tube or axle side tube, but heat can be effectively released by the vehicle body side tube or axle side tube.

Therefore, since it is possible to avoid the temperature increase of the coil, the insulation performance of the electric wire forming the coil is not impaired due to the chemical change of the insulating coating of the electric wire.

As a result, leakage of the coil is prevented and damage to the vehicle electronic shock absorber is limited.

This application claims the priority of Japanese Patent Laid-Open No. 2002-366415. The entire contents of Japanese Patent Laid-Open No. 2002-366415 are incorporated herein by reference.

While only selected embodiments have been selected to illustrate the invention, it will be apparent to those skilled in the art that various changes and modifications may be made within the scope of the invention as defined by the appended claims. In addition, the foregoing description of the embodiments according to the present invention has been provided for illustrative purposes only, and is not intended to limit the present invention as defined by the appended specification and equivalent constructions thereof.

As described above, according to the present invention, it is possible to provide an electronic shock absorber which can be applied to a vehicle in which the electromagnetic shock absorber uses electromagnetic force as a damping force, that is, can generate the damping force without using oil.

1 is a side sectional view of an electronic shock absorber for a vehicle of a first embodiment according to the present invention;

Fig. 2 is a side sectional view of an electronic shock absorber for a vehicle of a second embodiment according to the present invention;

Fig. 3 is a side sectional view of an electronic shock absorber for a vehicle of a third embodiment according to the present invention;

4 is a schematic representation of an electronic shock absorber in the art.

Fig. 5 is a side sectional view with the screw shaft engaged to the ball screw nut.

Fig. 6 is a side cross-sectional view with the center axis of the ball screw nut biased from the center axis of the screw shaft.

<Explanation of symbols for the main parts of the drawings>

1: vehicle body side tube

2: axle side tube

3: ball screw nut

4: screw shaft

5: connecting pipe

6: lower suspension spring receiver

7: upper suspension spring receiver

8: suspension spring

9, 10: bearing member

20: cushion spring

21: spring seat

32: frame

Claims (11)

The vehicle body side tube, An axle-side tube slidably inserted outside the vehicle body-side tube; An upper suspension spring receiver attached to the vehicle body side tube; A lower suspension spring receiver attached to the axle-side tube; A motor coupled to the inside or the outside of the vehicle body side tube; A ball screw nut moving integrally with the axle-side tube in the axle-side tube; A connecting pipe inserted into the vehicle body tube, one end of which is coupled to the ball screw nut and the other end of which is connected to the axle side; A screw shaft coupled to the motor shaft directly or through power transmission means in the ball screw nut, or integrally formed with the motor shaft and rotatably coupled within the ball screw nut, Converts the linear motion of the ball screw nut into the rotational motion of the screw shaft and transmits this rotational motion to the motor shaft to generate electromagnetic force in the motor, and axles torque against rotation of the motor shaft due to the electromagnetic force. The electromagnetic shock absorber for a vehicle used as a damping force which suppresses linear motion of a side tube. delete The vehicle body side tube, An axle-side tube slidably inserted outside the vehicle body-side tube; An upper suspension spring receiver attached to the vehicle body side tube; A lower suspension spring receiver attached to the axle-side tube; A shaft coupled to the inside of the vehicle body side tube; A coil wound on the shaft, a permanent magnet provided at a position opposed to the coil in the vehicle body side tube; A ball screw nut moving integrally with the axle-side tube in the axle-side tube; A connecting pipe inserted into the vehicle body tube, one end of which is coupled to the ball screw nut and the other end of which is connected to the axle side; A screw shaft coupled to the motor shaft directly or through power transmission means in the ball screw nut, or integrally formed with the motor shaft and rotatably coupled within the ball screw nut, Converts the linear motion of the ball screw nut into the rotational motion of the screw shaft and transmits this rotational motion to the motor shaft to generate electromagnetic force in the motor, and axles torque against rotation of the motor shaft due to the electromagnetic force. The electromagnetic shock absorber for a vehicle used as a damping force which suppresses linear motion of a side tube. delete delete delete The method according to claim 1 or 3, The vehicle body side tube further includes a rotation preventing device that prevents rotation about the ball screw nut. delete The method according to claim 1 or 3, A vehicle mounting portion having an upper suspension spring receiver connected between the vehicle body side tube and a motor; The electronic shock absorber further comprises a suspension spring inserted between the upper suspension spring receiver and the lower suspension spring receiver. The method according to claim 1 or 3, A vehicle mounting portion having a motor and an upper suspension spring receiver attached to a tip portion of the vehicle body side tube; The electronic shock absorber further comprises a suspension spring inserted between the upper suspension spring receiver and the lower suspension spring receiver. The method according to claim 1 or 3, Further comprising a vehicle mount, The vehicle mounting portion, A bracket connecting the vehicle mounting unit to the vehicle; A bush held and supported by the bracket, A rolling bearing held and supported by the bush, The upper suspension spring receiver is attached to the bracket, and the vehicle body side tube or motor is fitted to an inner surface of the rolling bearing.