JP2898427B2 - Braking method, braking device, braking power generation method, and braking power generation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking method, a braking device, a braking power generation method, and a braking power generation device, in which a part of kinetic energy is converted into electric energy so that a braking force can be adjusted. The present invention relates to a braking method for generating power, a braking device, a braking power generation method, and a braking power generation device.

[0002]

2. Description of the Related Art In a conventional braking device, as typified by a disk brake or a drum brake, a brake pad is pressed against a disk or a drum fixed to an object to be braked by hydraulic pressure or air pressure or the like, thereby causing friction between the brake pads. In this way, a braking force is applied to the braked body.

[0003] Adjustment of the braking force in this conventional device is performed by changing the pressing force of a brake pad against a disk or the like.

[0004]

In the conventional braking method, the braking force is adjusted by changing the pressing force. Therefore, when the braked body is stopped slowly so as not to stop suddenly. It is necessary to gradually decrease the pressing force.

However, it has been very difficult to finely adjust the pressing force by subtly changing the pressing force at a small value. This is because it is difficult to finely adjust the hydraulic pressure and air pressure, which are the driving sources of the brake pads, and it is difficult to finely adjust the friction between the brake pads and the disk when the frictional force is small.

In the conventional braking method, the kinetic energy held by the braked object is converted into frictional heat between the brake pad and the disk to perform braking, and a part of the kinetic energy is converted. It is not extracted as reusable energy.

[0007] The present invention has been made in view of these points, it is possible to freely adjust the braking force at the time of stop,
It is possible to prevent a sudden stop of the braked body, and to take out a part of the kinetic energy held by the braked body as electric energy.
It is an object to provide a braking device, a braking power generation method, and a braking power generation device.

[0008]

According to a first aspect of the present invention, there is provided a braking method for intermittently contacting a braking target with a braking contact medium at a predetermined frequency. The repetitive force received by the intermittent contact is applied to the piezoelectric element in accordance with its own vibration direction to excite the piezoelectric element to generate power, and the generated power is consumed by the load resistance to reduce the braking force. It is characterized by adjusting.

The braking method according to the present invention is characterized in that the braking contact medium is vibrated at the same frequency as the resonance frequency of the piezoelectric element.

The braking device according to a third aspect of the present invention provides a braking contact medium provided to be capable of coming into contact with and separated from a braked body, and intermittently applying the braking contact medium to the braked body at a predetermined frequency. It has a driving means for reciprocatingly vibrating so as to make contact, a piezoelectric element for applying the repetitive force received by the intermittent contact in its own vibration direction, and a load resistor for consuming power generated by the piezoelectric element. It is characterized by.

The braking device according to the fourth aspect is characterized in that the driving means is reciprocated at the same frequency as the resonance frequency of the piezoelectric element.

Further, the braking power generation method according to claim 5 is
The braking contact medium is intermittently contacted with the braked body while vibrating at a predetermined frequency while applying a braking force, and the repetitive force received by the intermittent contact is applied to the piezoelectric element in accordance with its own vibration direction. The piezoelectric element is applied to excite the piezoelectric element to generate power.

Further, the braking power generation method according to claim 6 is
The braking contact medium is vibrated at the same frequency as the resonance frequency of the piezoelectric element.

Further, the braking power generator according to claim 7 is
A contact medium for braking provided to be able to freely contact and separate from the object to be braked, and a driving means for reciprocatingly oscillating the contact medium for braking so as to intermittently contact the object to be braked at a predetermined frequency;
A piezoelectric element for generating electric power by applying the repetitive force received by the intermittent contact in its own vibration direction.

Further, the braking power generator according to claim 8 is
The driving means is characterized in that the driving means is caused to reciprocate at the same frequency as the resonance frequency of the piezoelectric element.

[0016]

By operating the braking device according to the third and fourth aspects in accordance with the braking method according to the first and second aspects, braking is performed on the body to be braked. Claims 5 and 6
By operating the braking power generation device according to claims 7 and 8 in accordance with the braking power generation method described above, braking and power generation are performed on the brake target.

That is, the braking contact medium is intermittently brought into contact with the braked object while vibrating at a predetermined frequency (for example, the same frequency as the resonance frequency of the piezoelectric element), and the repetitive force received by the intermittent contact is applied. Is applied to the piezoelectric element in accordance with its own vibration direction, the piezoelectric element is excited to generate power, and the generated power is consumed by the load resistance to adjust the braking force or take out the power.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is an embodiment showing both the braking device and the braking power generating device of the present invention.

In the apparatus 1 of the present embodiment, a cylindrical main body 2 is arranged coaxially with a disk-shaped disk 3 fixed to a brake target (not shown) to apply a braking force. At the upper end of the main body 2, there is provided a longitudinal vibration piezoelectric element 4 which generates longitudinal vibration as driving means also serving as a braking contact medium so as to face the disk 3 with a small interval. A driving power supply circuit 5 is connected to the piezoelectric element 4 for longitudinal vibration.
A voltage of a predetermined frequency is applied. A torsional vibration piezoelectric element 6 that generates electric power when subjected to torsional vibration is provided in a middle portion of the main body 2 in the axial direction. A load resistor 8 for power consumption and a power storage means 9 for power storage are selectively connected to an electric terminal of the torsional vibration piezoelectric element 6 via a switching element 7 so as to be selectively connectable.

Next, the operation of this embodiment will be described together with the braking method and the braking power generation method of the present invention.

To stop the rotating disk 3, the movable contact 7a of the switching element 7 is
And the drive power supply circuit 5 and the longitudinal vibration piezoelectric element 4
Is applied to the longitudinal vibration piezoelectric element 4 at a frequency at which the longitudinal vibration is performed at the same frequency as the resonance frequency of the torsional vibration piezoelectric element 6. As a result, the upper surface 4a of the vertical vibration piezoelectric element 4 also serving as a contact medium intermittently contacts the rotating disk 3 at the frequency of the vertical vibration, and applies a braking force to the disk 3 due to the frictional force between the two. . The main body 2 receives a torsion in the rotational direction of the disk 3 when the upper surface 4a of the longitudinal vibration piezoelectric element 4 is in contact with the disk 3, and returns the torsion by its own elasticity when not in contact. As a result, the main body 2 vibrates at the frequency of the longitudinal vibration, that is, the resonance frequency of the torsional vibration piezoelectric element 6. The torsional vibration of the main body 2 causes the torsional vibration piezoelectric element 6 to torsionally vibrate. Electric power is generated by the power generation action, and the electric power is consumed by the load resistor 8.

As described above, according to the present embodiment, the disk 3
A part of the kinetic energy of the disk 3 is converted into electric energy by the power generating action of the torsional vibration piezoelectric element 6 and the electric energy is consumed by the load resistor 8.
The braking force due to the friction between the disk and the upper surface 4a of the vertical vibration piezoelectric element 4 is reduced, and the disk 3 stops gently.

The operation at the time of braking will be described with reference to FIGS.

FIG. 2A shows a braking characteristic based on the relationship between the number of rotations of the disk and time, and FIG. 2B shows a driving power supply circuit (not shown) for driving the torsional vibration piezoelectric element 6. Shows the input / output characteristics of the torsional vibration piezoelectric element 6 when the electric resistance in the driving power supply circuit is the load resistance 8, and the solid line in the figure shows the case of the present embodiment.
The broken line indicates the case where both the piezoelectric elements 4 are stopped and braked based on the conventional method.

As shown in FIG. 2A, in the conventional example, the rotation speed of the disk 3 decreases linearly from the braking start time t0 and stops at the time t1. On the other hand, according to the present embodiment, it can be seen that the rotational speed of the disk 3 gradually decreases at least in a quadratic curve, and stops very slowly at time t2.

As shown in FIG. 2 (b), when the energization is stopped at time t0, in the conventional example, the fall of input power in the driving power supply circuit by the torsional vibration piezoelectric element 6, that is, the power generation is very small. Admitted. On the other hand, according to the present embodiment, a large fall of the input power is recognized, and power is generated by the torsional vibration piezoelectric element 6, and it is understood that the generated power is gradually consumed by time t3. .

According to FIG. 2A, although the stop time t2 of the disk 3 according to this embodiment is later than the stop time t1 of the conventional example, the time required for the vibration to settle down due to the sudden stop of the conventional example is added. Then, the stop time of the genuine disk 3 of the conventional example is much later than the stop time t2 of the present embodiment, and the superiority of the present embodiment becomes clear.

Further, in this embodiment, the braking force can be adjusted by changing the resistance value of the load resistor 8 to adjust the amount of power generated by the torsional vibration piezoelectric element 6.

That is, as shown in FIG. 3, FIG.
Similarly to the above, when the electric resistance in the driving power supply circuit of the torsional vibration piezoelectric element 6 was changed as the load resistance 8 and the resistance was changed, the B line without the resistance value was better than the A line with the resistance value. The number of revolutions of the disk 3 decreased slowly.

As described above, according to the present embodiment, when the disk 3 is stopped, the electric power generated in the piezoelectric element 6 for torsional vibration is consumed by the load resistor 8, so that the braking force is applied to the disk 3. The disk 3 stops gently. In addition, the braking force of the disk 3 can be adjusted by freely adjusting the braking force.

Further, if the load resistor 8 is a device that operates by consuming the generated power, the device of this embodiment functions as a braking power generation device that performs braking and generates power, and has extremely high energy efficiency. It will be excellent.

Further, when the movable contact piece 7a of the switching element 7 is supplied to the power storage means 9 during braking, the power generated by the torsional vibration piezoelectric element 6 is sequentially stored. Thus, the electric power stored in the power storage means 9 can be used at any time.

FIG. 4 shows another embodiment of the present invention.

The device 11 of the present embodiment includes the brake drum 1
Brake pad 1 as a contact medium for braking on the outer peripheral surface of 2
3 is formed so as to apply a braking force by bringing them into contact with each other. In the present apparatus 11, a main body 14 is disposed so as to be orthogonal to the axial direction of the brake drum 12. A first longitudinal vibration piezoelectric element 15 as a driving means is provided at an end of the main body 14 such that the brake pad 13 attached to the tip faces the outer peripheral surface of the brake drum 12 at a small interval. ing. A voltage of a predetermined frequency is applied from the drive power supply circuit 16 to the first longitudinal vibration piezoelectric element 15. A second longitudinal vibration piezoelectric element 17 that generates electric power when receiving longitudinal vibration in the longitudinal direction is provided at a middle part in the longitudinal direction of the main body 14. This second longitudinal vibration piezoelectric element 17
Are connected to a load resistor 19 for power consumption and a power storage means 20 for power storage via a switching element 18 so as to be selectively switched and connectable.

Next, the operation of the present embodiment will be described together with the braking method and the braking power generation method of the present invention.

When the rotating brake drum 12 is stopped, the movable contact piece 18a of the switching element 18
Is applied to the load resistor 19 side, and a driving voltage having a frequency that causes the driving power supply circuit 16 to vertically vibrate the first longitudinal vibration piezoelectric element 15 at the same frequency as the resonance frequency of the second longitudinal vibration piezoelectric element 17 is applied to the first driving voltage. The voltage is applied to the piezoelectric element 15 for longitudinal vibration. As a result, the brake pad 13 serving as a contact medium intermittently contacts the rotating brake drum 12 at the frequency of the longitudinal vibration, and applies a braking force due to the frictional force between the two. When the brake pad 13 is in contact with the brake drum 12, the main body 14 is compressed by receiving a force in a tangential direction (the right-hand direction in FIG. 4) in the rotation direction of the brake drum 12. Restored by elasticity. Accordingly, the main body 14 longitudinally vibrates at the frequency of the longitudinal vibration, that is, the resonance frequency of the second piezoelectric element 17 for longitudinal vibration. Due to the longitudinal vibration of the main body 14, the second
The vertical vibration piezoelectric element 17 vibrates longitudinally, and power is generated by the power generation action, and the power is consumed by the load resistor 19.

In this manner, in this embodiment, braking and braking power generation are performed in the same manner as in the previous embodiment.

The switching elements 7 and 18
Is shown in FIGS. 1 and 4 as a symbol,
Operation characteristics are good when formed by an electronic circuit using a semiconductor element.

The present invention is not limited to the above-described embodiments, but can be modified as needed.

[0041]

As described above, since the braking method, the braking device, the braking power generation method and the braking power generation device of the present invention are constructed and operated, the braking force at the time of stop can be freely adjusted, and Abrupt stop of the body can be prevented, and a part of the kinetic energy held by the brake target can be extracted as electric energy, so that the energy efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a braking device and a braking power generation device of the present invention.

FIG. 2A is a characteristic diagram showing a braking characteristic based on a relationship between the number of rotations of a disk and time, and FIG. 2B is a piezoelectric element for torsional vibration when electric resistance in a driving power supply circuit is a load resistance. Characteristic diagram showing input / output characteristics of

FIG. 3 is a characteristic diagram showing a braking characteristic when a value of a load resistance is changed.

FIG. 4 is a perspective view showing another embodiment of the braking device and the braking power generation device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 11 Braking device and braking power generation device 3 Disk 4 Piezoelectric element for longitudinal vibration 6 Piezoelectric element for torsional vibration 7, 18 Switching element 8, 19 Load resistance 12 Brake drum 13 Brake pad 15 First piezoelectric element for longitudinal vibration 17 Second Piezoelectric element for longitudinal vibration

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-116980 (JP, A) JP-A-2-142267 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02N 2/00

Claims (8)

(57) [Claims] An intermittent contact is made between a braking contact medium and a braked body at a predetermined frequency while vibrating at a predetermined frequency, and a repetitive force received by the intermittent contact is applied to the piezoelectric element in accordance with its own vibration direction. And a braking force is adjusted by exciting the piezoelectric element to generate electric power and consuming the generated electric power by a load resistor. 2. The method according to claim 1, wherein the braking contact medium is vibrated at the same frequency as the resonance frequency of the piezoelectric element.
The braking method described in the above. 3. A braking contact medium provided to be able to freely contact and separate from the braked body, and a drive means for reciprocatingly oscillating the braking contact medium at a predetermined frequency so as to contact the braked body intermittently. A braking device comprising: a piezoelectric element for applying a repetitive force received by the intermittent contact in its own vibration direction; and a load resistor for consuming power generated by the piezoelectric element. 4. The braking device according to claim 3, wherein the driving means is reciprocated at the same frequency as the resonance frequency of the piezoelectric element. 5. A braking medium is intermittently brought into contact with an object to be braked while vibrating a braking contact medium at a predetermined frequency to apply a braking force, and a repetitive force received by the intermittent contact is applied to the piezoelectric element by its own characteristic. A braking power generation method, characterized in that the power is applied in accordance with the vibration direction to excite the piezoelectric element to generate power. 6. The braking contact medium vibrates at the same frequency as the resonance frequency of the piezoelectric element.
4. The braking power generation method according to 1. 7. A contact medium for braking provided so as to be able to contact and separate from the object to be braked, and a driving means for reciprocating the contact medium for braking so as to intermittently contact the object to be braked at a predetermined frequency. And a piezoelectric element that generates electric power by applying the repetitive force received by the intermittent contact in its own vibration direction. 8. The braking power generator according to claim 7, wherein the driving means is caused to reciprocate at the same frequency as the resonance frequency of the piezoelectric element.