JPH03107360A - Drive unit - Google Patents

Abstract

PURPOSE:To prevent the generation of noise through collision by stopping the output body of a drive unit not by the collision with a stopper but by the attractive force by magnetic force. CONSTITUTION:The pole parts of an electromagnet is provided at an interval that it can oppose a pair of magnets N and S, consequently in case that the magnetisms arising at pole parts 40a and 40b by the excitation of the second electromagnet 4 become, respectively N and S combinations with the polarities of one pair of magnets 7 and 8, the magnetic parts and the magnets attract each other, and an output shaft 2 shifts so that both may get in opposed conditions. And in this condition, the current application to the electromagnet is stopped, and the output shaft is held at that position. Next, the first electromagnet 3 dislocated is excited so that the pole parts 30a and 30b may have the magnetisms of attracting other one pair of magnets 6 and 7 with each other, whereupon by both attractive forces, the output shaft shifts in the reverse direction so that both may be opposed to each other. The shift and stoppage of the output body is done by the attractive force by the magnetic force this way, the generation of the collision noise can be prevented.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a drive device.

(Prior art) Conventionally, as a drive device, for example,
The one described in Japanese Patent No. 637 is known.

This drive device is configured to stop driving the output rotation shaft, and includes a stopper that collides with a convex portion of the output rotation shaft to stop the movement of the output rotation shaft, and a buffer member that supports the stopper. This was designed to reduce the impact when the output rotating shaft collides with the stopper.

(Problem to be solved by the invention) However, in such a conventional drive device,
Since the rotation of the output shaft is mechanically stopped by a stopper, problems arise in that collision noise is generated and durability is reduced due to the impact caused by the collision.

In addition, in order to maintain the state in which the output rotation shaft is regulated in position by the stopper, a drive voltage is applied to the drive device to apply a load, which may result in overload, which may also cause problems with durability. It leads to a decline in sexuality.

The present invention was made by focusing on such problems,
It is an object of the present invention to provide a drive device that can eliminate stopper collision noise and improve the durability of an actuator.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the drive device of the present invention has the following features:
an output body movably provided within the casing; and an output body provided on one of the casing and the output body, arranged at predetermined intervals so that N poles and S poles are alternately lined up along the moving direction of the output body. three magnets, and a first electromagnet and a second electromagnet provided close to the magnets on the other side of the casing and the output body, and both electromagnets each have an N.S. The pole parts where the poles are generated are provided at intervals that allow them to face the N-SL set of the magnets, and when the pole part of one electromagnet faces the N-31 set of magnets, the pole part of the other electromagnet but,
Both electromagnets were provided at intervals in the direction of movement of the output body so as to be offset by a predetermined amount from the positions facing the magnets of the other N and SL sets.

(Function) In the drive device of the present invention, when at least one of the first electromagnet and the second electromagnet is excited, an N.
A magnetic pole of S is generated.

Since the pole parts of this electromagnet are provided at a distance that allows them to face the N-3L set of magnets, the polarity generated in the pole part due to the excitation of the electromagnet is the same as the polarity of one set of magnets and the N-3 combination. In this case, the output body moves so that the pole part and the magnet attract each other and are in a state where they face each other.

In this state, even if the energization of the electromagnet is stopped to release the excitation state, the magnetic attraction force attracts the pole portion of the electromagnet, and the output body is held in that position.

In addition, since the first electromagnet and the second electromagnet are provided at a predetermined interval, as described above, when the pole part of one electromagnet and the N/S pair of magnets face each other, the other electromagnet The pole portions of the magnets and the other N-31 set of magnets are arranged to be shifted from each other by the distance between the two electromagnets, and are not facing each other.

Therefore, this time, the electromagnet whose position is shifted,
When it is excited so that its polar part becomes polarized so that it attracts the other N/S1 set of magnets.

Due to the attraction force between the two, the output body moves in the opposite direction to that described above so that the two face each other.

In this way, when one electromagnet and the N/SL set of magnets attract each other, the pole of the other electromagnet and the other N/S1 set of magnets facing it repel each other. When excited in this way, this repulsive force is also added, making the movement of the output object even smoother.

In this way, the movement of the output body is not stopped by a collision with a stopper, but by the attraction force generated by the magnetic force, so no collision noise is generated, and moreover, no impact force is applied to the output body, etc. It cannot be added.

Furthermore, since the position of the output body is maintained by the suction force of the magnet without applying any load to the driving part, there is no possibility that the driving part will be overloaded.

(Example) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, the configuration of the embodiment will be explained. In this embodiment, an actuator that operates a damping force variable means of a hydraulic shock absorber will be explained as an example.

However, as the damping force variable hydraulic shock absorber, for example,
The description in the second embodiment of FIG. 5 of U.S. Pat. This variable damping force hydraulic shock absorber has a structure in which a spool provided within the piston rod slides in the axial direction of the piston rod to change the damping force characteristics between hard and soft.

The drive device slides the spool in the variable damping force type hydraulic shock absorber as described above, and in this embodiment, as shown in FIG. 1, a linear drive type is used. Based on the drive of this drive device, the damping force generated by the variable damping force type hydraulic shock absorber is changed.

That is, in the same figure, 1 is a casing, which is formed in a cylindrical shape from a non-magnetic material, and has side walls 1 that close openings at both ends.
A through hole 10.11 is bored in the center of each of a and 1b. This through hole 10.11 has a bearing 12.1.
A cylindrical output shaft (output body) 2 made of magnetic material via 3
is attached so that it can slide freely in the left and right directions in the figure.

Furthermore, a first electromagnet 3 and a second electromagnet 4 are provided within the casing 1.

The first electromagnet 3 is composed of a first stator 30 having a gate-shaped cross-sectional shape and an annular shape, and a first annular excitation coil 31 provided in a hollow portion of the first stator 30. 4 also has a second stator 4 having a gate-shaped and annular cross-sectional shape.
0 and an annular second excitation coil 41 provided within the hollow portion of the second stator 40.

Both electromagnets 3.4 are arranged in the axial direction between the side walls 3a, 3a of both stators 30, 40 and between the side walls 4a, 4a with an annular spacer 5 made of a non-magnetic material interposed therebetween. The side walls 3a, 4a of .40 are fixedly sandwiched between the side walls 1a, Ia of the casing l.

Further, both electromagnets 3.4 are connected to both excitation coils 31.41.
Both stators 3 are energized by controller C.
It is a device that generates a magnetic field of 0.40 mm and has 1 stator and 30 mm.
Pole portions 30a and 30b are provided at both ends (the annular inner circumferential end surfaces of both side walls) of 40, respectively.

40a and 40b are formed. That is, in this pair of pole parts 30a, 30b and 40a, 40b, N and S magnetic poles are generated when both excitation coils 31 and 41 are energized, and when the energization direction is reversed, The polarity of N-3 is reversed.

In the present embodiment, both excitation coils 31.41 are connected, and when the coils 31.41 are energized in a certain direction, each pole portion 30a, 30b.

40a and 40b are S, N, S, and N, respectively,
When energized in the opposite direction, it is configured to become N, S, N, S.

Three annular magnets 6.7.8 are attached to the outer periphery of the output shaft 2 in close proximity to the pole portions 30a, 30b, 40a, 40b of the stator 30° 40 in the radial direction of the output shaft 2. .

Each magnet 6.7.8 is arranged so that N poles and S poles are arranged alternately, and in this embodiment, S poles, S poles,
The polarity is N pole and S pole. The magnet 6.7.8 and both electromagnets 3.4 are provided so that the pole parts 30a, 30b of the first electromagnet 3 and the magnet 6.7 can face each other, as shown in FIG. As shown in (d), the pole parts 40a, 40b of the second electromagnet 4 and the magnet 7.8 are provided so as to be able to face each other.

Next, the operation of this embodiment will be explained based on the operation diagram shown in FIG.

FIG. 2(a) shows a state in which the output shaft 2 is sliding to the left and both excitation coils 31.41 are not energized, that is, both electromagnets 3.4 are in a non-excited state. In this state, the pole portion 30 of the stator 30 in the first electromagnet 3
a and 30b are attracted by the magnetic force of the left magnet 6 and the center magnet 7, which are close to each other, and this bow suction force prevents the output shaft 2 from sliding and holds it in this position. It is in a state.

Next, when sliding the output shaft 2 from the position (a) to the right, as shown in the same figure (b), the pole part 30a is the south pole, the pole part 30b is the north pole, Both excitation coils 31 and 41 are energized so that the excitation coils 31 and 41 become the south pole and the pole part 40b becomes the north pole.

Then, a repulsive force acts between the 5-N1 set by the magnet 6.7 and the pole parts 30a, 30b of the first electromagnet 3, and the N/SI set by the magnet 7.8 and the second electromagnet 4
An attractive force acts between the pole parts 40a and 40b.

The output shaft 2 slides to the right in the figure due to the repulsive force and attractive force caused by this magnetic force, and as shown in FIG.
Sliding of the output shaft 2 is stopped at a position where the pole parts 40a and 40b face each other.

Next, in this state, when the energization to the side excitation coils 31.41 is canceled and both electromagnets 3.4 are brought into a non-excited state, as shown in FIG.
As shown in d), the pole parts 40a, 40b of the second electromagnet 4
However, they are attracted by the magnetic force of the center magnet 7 and the right magnet 8, which face each other closely, and this attractive force prevents the output shaft 2 from sliding and holds it in that position. .

Next, from the state shown in FIG. 2(d), the side excitation coil 31.4
In contrast to 1, if the current is passed in the opposite direction to the above case,
Both electromagnets 3.4 are excited, and the pole parts 30a, 30b, 40
a and 40b become the north pole, south pole, north pole, and south pole, respectively.

Therefore, an attractive force acts between the 5-N1 set by the magnet 6.8 and the pole parts 30a, 30b of the first electromagnet 3, and the N/S1 set by the magnet 7.8 and the pole part of the second electromagnet 4. 40a and 40b, and the output shaft 2 slides to the left in the figure, contrary to the above case.

Then, when the left magnet 6 and the center magnet 7 slide to a position where they face the pole parts 30a, 30b of the first electromagnet 3, the sliding is stopped.

Then, in this state, when the power to the side excitation coil 31.41 is released and both electromagnets 3.4 are brought into a non-excited state, as shown in FIG.
, 30b are attracted by the magnetic force of the left magnet 6 and the center magnet 7, which face each other in close proximity, and this attraction prevents the output shaft 2 from sliding and holds it in that position. becomes.

As explained above, in the drive device of this embodiment, since the sliding of the output shaft 2 is stopped by magnetic force, there is no impact when the output shaft 2 is mechanically stopped by a stopper, and therefore collision noise is generated. Furthermore, the drive device and its drive transmission system are not subjected to manual impact, resulting in improved durability.

In addition, the position of the output shaft 2 is held by magnetic force, and no load is applied to the driving part, so there is no overload, which also improves durability. .

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments.

For example, in the embodiment, the present invention is applied to a linear drive type drive device, but it can also be applied to a rotary drive type drive device.

Further, although a ring-shaped output body is shown in the embodiment, other output bodies such as a plate-shaped output body may be used.

(Effects of the Invention) As explained above, in the drive device of the present invention, the movement of the output body is not stopped by a collision with a stopper but by the attraction force generated by the magnetic force, so that collision noise is generated. At the same time, you can obtain the effect that it will not occur, and at the same time,
During this stop, no impact force is applied to the output object, etc. (
, the effect of improving durability can be obtained.

Furthermore, since the position of the output body is held by the suction force of the magnet without applying any load to the drive part, there is no overload on the drive part, which also improves durability. .

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a driving device according to an embodiment of the present invention, and FIG.
Figures (a) to (d) are explanatory views of the operation of the drive device of the embodiment. ■...Casing 2...Output shaft (output body) 3...First electromagnet 4...Second electromagnet 6...Magnet 7...Magnet 8...Magnet 30a...Pole part 30b...Pole part 40a...Pole part 40b...Pole part

Claims (1)

[Claims] 1) An output body movably provided in a casing, and provided on one of the casing and the output body, with N poles and S poles arranged alternately along the moving direction of the output body. three magnets arranged at predetermined intervals as shown in FIG. When the pole parts where N and S poles occur during excitation are provided at a distance that allows them to face the N and S1 pairs of the magnets, and when the pole parts of one electromagnet face the N and S1 pairs of magnets, , characterized in that both electromagnets are provided with an interval in the moving direction of the output body so that the pole part of the other electromagnet is shifted by a predetermined amount from the position facing the other N/S1 set of magnets. Drive device.