HK1069931B - Piezomotor with a guide - Google Patents

Description

The present invention relates to a drive system consisting of at least one motor, each containing at least one mechanical vibration generator, and at least one resonator and a device powered by the motor (1), whereby the resonator has a contact surface which interacts with the surface of the device to drive it.

Motors that operate with a mechanical vibration generator are an alternative propulsion concept to small electric motors, which are usually too loud and too expensive. These types of motors have at least one vibration generator that generates mechanical vibrations, which are amplified, for example, by a resonator, and transmitted by this resonator to and drive a device to be actuated, such as a rod or wheel. The resonator bodies vibrate advantageously at a resonance frequency, but the amplitude of the vibrations depends in any case strongly on the frequency of the vibration generator on the mechanical vibrations generated.

However, these drive systems have the disadvantage that, due to manufacturing tolerances, vibration components often do not act in the direction of the desired motion-generating direction and that the rod or rotor does not remain in the desired position or track or that additional guidance elements are not required.

The challenge was therefore to provide a drive system which did not have the disadvantages of the state of the art.

This task is performed by a drive system as described in claim 1.

It was very surprising to the specialist that a device on the contact surface of the resonator and/or a device on the surface of the device could channel the vibration components in the direction of the desired motion-generating vibration and stabilize the device in the desired direction or position with a reduced effort on the external position.

Preferably, the agent shall be at least an incision or protrusion in the contact surface of the resonator or the surface of the device to be applied.

The product is also preferable to an area on the contact surface of the resonator or the surface of the device to be applied, the coefficient of friction of which differs from the other areas of the contact surface or surface.

The engine is designed to be driven by a motor with a maximum speed of between 20 km/h and a maximum speed of between 30 km/h.

In the present invention, the resonator has a contact surface that interacts with and drives a propelling body. Preferably, this contact surface oscillates asymmetrically in several directions, whether or not it is in contact with the propelling body. Most preferably, the contact surface performs an elliptical motion. Also preferably, this contact surface oscillates at different operating frequencies, preferably resonant frequencies, of the piezo motor, in different directions, whether or not it is in contact with the propelling body, and eliminates the macroscopic movements required for the respective propelling body, so that no additional mechanisms or components are required for the propelling body.

In a preferred embodiment, the drive system shall have at least two motors, which may be of equal or opposite arrangement.

The engines are preferably pushed against the device by means of a spring component, for example.

If the drive system of the invention has several motors, these are preferably controllable individually or in parallel, and the motors operate preferably at different frequencies and/or amplitudes.

The drive system is preferably so designed that the device can be driven translatory and/or rotary, with the drive being bidirectional in a preferred embodiment of the present invention. Preferably the motor performs a cyclically recurring motion. Each cycle involves a certain amount of drive of the driven device, with the drive being possible over any distance.

Preferably, the vibration generator is made of a piezoelectric material. In particular, the vibration generator is a single piezoelectric component made of a monolithic multilayer structure consisting of a stack of at least two ceramic layers and an electrode layer arranged between two ceramic layers. In a highly preferred design of the invention, the electrode layers are essentially made of copper.

In another particularly preferred design of the invention, the piezoelectric component has two terminals through which at least one signal is transmitted to the component and induces vibration. The terminal is understood to be the connection between the electrical line through which the signal is transmitted from the source of the excitation to the piezo motor and the piezoelectric component. In a particularly preferred design of the invention, the piezoelectric component is first transmitted a signal and the contact surface of the resonator body is stimulated to vibrate in one direction. Similarly, when a second electrical signal is transmitted to the piezoelectric component, the contact surface is stimulated to vibrate in a second direction.

In a particularly advantageous design of the drive system of the invention, the signal transmitted to the piezoelectric component is sine-shaped or rectangular in shape, so that the generation and transmission of a saw-tooth signal is not necessary.

In another preferred design of the invention, the contact surface of the resonator body, which interacts with the surface of the device, is stimulated to such vibrations that the device can be driven in two directions at two signals transmitted to the piezoelectric component with different frequencies, preferably eigen-resonance frequencies, whereby the amplitude of the vibrations depends strongly on the frequency.

In another preferred design of the invention, the engine has an essentially two-dimensional shape in which the geometric shape is essentially unchanged in the third plane of space, preferably perpendicular to the plane stretched by the first two axes, but the expert understands that the principle of the two-dimensional shape according to the invention is realized even if there are small deviations from the two-dimensionality, for example by lateral declinations of edge areas.

In another preferred embodiment of the invention, the transmission of power from the motor to the actuated device is improved by having notches on the contact surface of the resonator body or the surface of the devices to be actuated, which can channel the vibration components in the direction of the desired motion-generating vibration and/or stabilize the device in the desired position with a reduced effort on external storage.

The indentations in the contact surface of the resonator or on the surface of the device to be actuated may be made in any manner familiar to the skilled person, for example by means of a de-slip or plastic forming process, into the contact surface of the resonator or the surface of the device, and may be formed, for example, by casting or injection moulding the component into the device.

In another preferred embodiment, the indentations can also be produced by abrasion between the resonator and the device.

The propulsion system according to the invention may be designed to exhibit the characteristics of a stepper motor. This is achieved by causing, due to the surface structure and/or shape of the surface, different contact situations between the resonator and the device, which are caused by different advances of the device. In the case of a motor arrangement, a vibrational stimulation causes the device to move until the contact situation changes in such a way that the motion is induced or induced. If then switched to another arrangement, the zone with the changed contact situation is moved in such a way that the device moves until another contact situation is reached. The specific vibrational behavior of the sensor or the other actuator can then be determined either by changing the direction of the electrical contact or by changing the direction of the electrical contact.

Multiple motors designed to produce different vibration at the same electrical stimulation may also be used.

The motors can be positioned in such a way that they experience identical contact situations each time. However, a particularly advantageous arrangement is one slightly shifted from the contact situations so that the motors experience different contact situations at the same time. In this arrangement, the motors having a particularly favourable contact situation for propulsion can contribute the proportion of propulsion needed for movement. If these motors leave the area of favourable contact, the movement ceases.

A special variant of the invention is a version with only one motor but with more than one contact surface. Each of the contact surfaces of the motor may be at or detached from the device 4 in different contact situations.

The drive system of the invention can channel almost all the vibration components in the desired direction and stabilize the position of the device to be actuated.

The following illustrations illustrate the invention using figures 1 to 13 and are intended as illustrations only and do not restrict the general idea of the invention. Figure 1 shows the drive system according to the invention with a protrusion of the resonator contact surface.Figure 2 shows the drive system according to the invention with a protrusion of the resonator contact surface and a protrusion of the device surface.Figure 3 shows the drive system according to the invention with an protrusion of the resonator contact surface.Figure 4 shows complementary shapes of the contact surface of the resonator system and the device surface.Figure 5 shows a possible surface design of a protrusion in the device surface.Figure 6 shows the surface design with several different protrusions.Figure 7 shows the drive system according to the invention.Figure 9 shows a motor system with two protrusions.Figure 8 shows a motor system with three protrusions.Figure 11 shows a motor system with two protrusions.Figure 8 shows a motor system with two protrusions.Figure 11 shows a motor system with three protrusions.Figure 12 shows a motor with two protrusions.Figure 11 shows a motor system with two protrusions.Figure 8 shows a motor system with two protrusions.Figure 11 shows a motor with two protrushes.Figure 13 shows a motor with two protrushes.Figure 9 shows a motor with two protrushes.

The engine 1 has a vibration generator 2 made of piezoelectric material, which generates vibrations which are transmitted to the resonator 3. The resonator 3 has at its tip a contact surface 7 which interacts with the surface 6 of the rod 4 and drives it forward and backward or rotating. The contact surface 7 has a notch so that the resonator 3 encloses the rod 4 in a straight line. The motor 1 is mounted on a spring 8 over the resonator 3 on a spring 7 which is mounted on the rod 7 of the resonator 4 and pushes it back against the rod 3.

In Figure 2 a further embodiment of the drive system of the invention is shown. In this case, the contact surface 7 of the resonator 3 has a protrusion 5 which interacts with an indentation in the surface of the rod 4. This embodiment of the drive system of the invention channels the vibrations in the desired direction on the one hand and the rod 4 is guided by the engine 1 on the other.

Figure 3 shows another embodiment of the drive according to the invention. In the present case, the contact surface 7 of the resonator 3 has a notch 5 which interacts with a rotor 4 having a curved surface 6. The drive according to the invention analyses the vibrations in the desired direction on the one hand and guides the rotor 4 by the resonator 3 on the other.

Figure 4 shows a large number of possible protrusions or protrusions of the contact surface of the resonator body or the surface of the powered device.

Figure 5 shows another particular design of the contact surface of the resonator body or the surface of the powered apparatus. In this case, the contact surface 7 of the resonator body has a protrusion 5. The surface 6 of the powered apparatus 4 has two protrusions, so that a groove forms over a certain section of the surface 6. Also, the interaction of the groove 5 with the groove channels the vibrations in the desired direction and stabilizes the apparatus 4 in its position.

Figure 6 also shows a particular design of the resonator contact surface and the surface of the powered device. In this case the resonator surface has a protrusion and the surface 6 a variety of protrusions. In the figure on the left the resonator body interacts with a larger contact surface area and thus with a large friction area. In the figure on the right the resonator body interacts with a small contact area and thus with a small friction area.

Figure 7 shows the propulsion system of the invention with a propelled rotor having a large number of protrusions or protrusions 5 and two motors, which are in this case equally arranged. The resonator bodies are pushed against the propelled device 4 by means of springs 8 with different compressive forces. The compressive force varies periodically with rotation of the rotor 4. The motors can be operated either separately or in parallel at different frequencies and amplitudes.

Figure 8 is essentially the same as Figure 7, except that in this case the engines are arranged opposite each other.

Figure 9 shows a three-motor propulsion system of the invention. The angles at which the motors are arranged around the propelled rotor are determined by the number of protrusions 5 and are given by the general formula $\text{Winkel des Motors = 360/(Ausbuchtungsanzahl) × (n + Motor-Nr./}\text{/ Motoranzahl) + K}$ The Commission has already made a number of recommendations.

The number of protrusions is in this case 10, the engine number is either 1, 2 or 3. n is a freely selectable integer for each engine and the constant K is a constant that is the same for all engines. In this case, n = 1 and K = 0 The engines can be arranged at uniform or irregular intervals. In particular, the engines can be designed differently in their operating frequency. The engines can all be switched in parallel or controlled individually.

The surface has two strips of periodically recurring protrusions, which are placed in a position opposite to each other, in which the resonator has two contact zones which, depending on the electrical excitation of the resonator, alternately contribute to the propulsion of the rotor.

The drive system shown in Figure 11 is essentially the same as the drive system shown in Figure 10, except that the rotor has no protrusions but zones with different coefficients of friction.

Figure 12 shows a device 4 whose surface has zones with different coefficients of friction 9, 10. Zone 10 has a higher coefficient of friction than Zone 9. This arrangement guides the runner, since the speed of the thrust depends on the coefficient of friction. Depending on the vibration form, both the high and low friction range can lead to higher thrust speeds.

Figure 13 shows a further arrangement of areas with different coefficients of friction.

The expert will see from all the examples that the device can be any shape and not limited to the shape of a rod or a rotor, for example the rod can also be wavy and the device can be a plate, preferably with nuts or a strip with a different coefficient of friction to the rest of the plate.

The expert further recognizes that the bulges and the different coefficients of friction can also be used in combination in a drive system.

Claims (13)

1. A drive system, comprising at least one motor (1) having at least one vibration generator (2) each as well as at least one resonator (3) each and a device (4) that is driven by the motor (1), wherein the resonator (3) comprises a contact area (7) that cooperates with the surface (6) of the device (4) to drive said device, characterized by the resonator contact area (7) comprising a means or the device surface (6) comprising a means that interacts with a contact area of a resonator, and by the means guiding the device (4).
2. The drive system of claim 1, characterized by the means comprising at least an indentation or protrusion (5) or the contact area (7) and/or the surface (6) comprising regions with differing friction coefficients.
3. The drive system of claim 1 or 2, characterized by the surface (6) comprising a plurality of indentations or protrusions (5) or several regions with differing friction coefficients each that are spaced apart in regular intervals with respect to each other.
4. The drive system of claim 2 or 3, characterized by the indentations or the protrusions (5) having a respective depth or height of 0.05 - 10 mm, preferably of 0.5 - 3 mm.
5. The drive system of one of claims 1 through 4, characterized by comprising at least two motors (1) that are arranged in identical or opposing orientations.
6. The drive system of claim 5, characterized by the motors being urged against the device (4) with respective forces (F) that differ from each other.
7. The drive system of one of claims 5 or 6, characterized by the motors being controllable individually or in parallel.
8. The drive system of one of claims 5 through 7, characterized by the motors each being operable at differing frequencies and/or with differing amplitudes.
9. The drive system of one of claims 1 through 8, characterized by the device (4) being movable in a translating or rotary, preferably bi-directional, fashion.
10. The drive system of one of claims 1 through 9, characterized by the piezoelectric generator (2) comprising a piezoelectric material.
11. The drive system of one of claims 2 through 10, characterized by the indentation (5) being producible by wear.
12. The drive system of one of claims 1 through 11, characterized in that it has the characteristics of a stepper motor.
13. The drive system of one of the previous claims, wherein the force of the generated motion is predetermined by the position of the device or the rotor rotation angle when the excitation remains the same.