JPH03243179A - Ultrasonic carrying device - Google Patents

Abstract

PURPOSE:To eliminate the limit of a carrying route by a method wherein an ultrasonic oscillator is pushed by a pushing device against a rail member while a yoke member is guided to said rail member by a guiding device. CONSTITUTION:A yoke member 16 is provided with a pushing device for pushing an ultrasonic oscillator 20 against a rail member 12 or a holder 24, a male screw member 26, a spring pusher 28, and a leaf spring 30. Independently from the pushing device, a guiding device or a guide rail 14 and an engaging unit 18, guiding the yoke member 16 into the carrying direction while precluding separation between the yoke member 16 and the rail member 12, are provided. Accordingly, the pushing force of the ultrasonic oscillator 20 against the rail member 12, which is generated by said pushing device, is not changed. Further, the yoke member 16 can be guided into the carrying direction while preventing the inclination of the yoke member 16 in the moving direction and a direction orthogonal to the moving direction of the yoke member 16, deviation in a direction parallel to the moving direction and the like by said guiding device. According to this method, carrying can be effected nicely even in a curved or an inclined carrying route.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an ultrasonic conveyance device, and particularly to an ultrasonic conveyance device that is suitable for conveyance not only along a straight, flat conveyance path, but also along a curved or inclined conveyance path. It is about the technology that allows you to obtain.

2. Description of the Related Art A system comprising an ultrasonic vibrator that is vibrated ultrasonically, and a yoke member provided with a pressing means for pressing the ultrasonic vibrator against a rail member with a predetermined pressing force, the ultrasonic vibrator and the rail member. An ultrasonic motor is known in which a driving force is generated between the motor and the motor.

For example, patent application No. 1-4686 filed earlier by the present applicant.
This is what is described in the specification and drawings of No. 6. According to this ultrasonic motor, the ultrasonic vibrator is fixed to the yoke member at its vibration node, that is, at a region with less vibration, so that the ultrasonic motor This has the advantage that the operation of the sonic vibrator is stable and highly efficient power can be obtained.

By the way, in such an ultrasonic motor, some kind of guide mechanism is required to prevent the moving mechanism from shifting laterally or wandering. If provided, the structure of the moving mechanism would become complicated, which would generate unnecessary vibrations, increase the weight, and reduce responsiveness.

In contrast, the present applicant has developed a simple guide mechanism that guides the moving mechanism along the ultrasonic transducer and the rail G that it contacts by forming recesses and protrusions that engage with each other. devised an ultrasonic motor with

This is what is described in the specification and drawings of Japanese Patent Application No. 1-224879 previously filed by the present applicant.

Problems to be Solved by the Invention However, in the ultrasonic motor described in Japanese Patent Application No. 1-224879, the guide mechanism that guides the moving mechanism and the pressing mechanism that presses the ultrasonic transducer against the rail are
Since the structure includes a coil spring as a common member, the guide equipped with the roller bearing that forms part of the movement mechanism can be moved without changing the pressing force of the ultrasonic transducer against the rail due to the urging force of the coil spring. It has been difficult to guide the guide in accordance with the direction of the rail while preventing directional inclination, inclination in the direction perpendicular to the movement direction, deviation in the direction parallel to the movement direction, etc. In this case, if the rail that is the conveyance path has a curved part, when guiding the guide along the curved rail, the approximate axis of the roller bearing provided on the guide is When the frictional resistance against the rail in the direction is large, a relatively large force acts on the guide mechanism in a direction substantially perpendicular to the guide direction and substantially in the axial direction of the roller hair ring through the roller bearings, guides, etc. It is desirable to reduce the biasing force of the coil spring, but if the biasing force of the coil spring is reduced,
It becomes difficult to secure a sufficient driving force of the ultrasonic motor, and the reduction in the driving force may make transport difficult on steep uphill slopes.

The present invention has been made against the background of the above circumstances,
The purpose is to provide an ultrasonic conveyance device that is capable of suitably conveying not only linear and flat conveyance paths, but also along curved and inclined conveyance paths, and which has no limitations on conveyance paths. There is a particular thing.

Means for Solving the Problems The gist of the present invention to achieve the above object is to provide a method for creating a system between an ultrasonic vibrator that is subjected to ultrasonic vibration and a fixed-position rail member that is in contact with the ultrasonic vibrator. An ultrasonic conveyance device of a type that conveys conveyance in a predetermined direction based on a generated driving force, comprising: (a) a yoke member, and (b) a yoke member provided with the ultrasonic transducer and a rail member. (C) a pressing device provided between a portion of the ultrasonic vibrator with a small vibration amplitude and the yoke member, and a relative position of the pressing direction between the ultrasonic vibrator and the yoke member; (d) a retaining device that allows movement but prevents relative movement in the direction of conveyance; (d) provided between the rail member and the yoke member to prevent separation between the rail member and the yoke member; and a guide device for guiding the yoke member in the transport direction.

Operation and Effects of the Invention With this structure, the pressing device for pressing the ultrasonic transducer against the rail member is provided on the yoke member, and independent of this pressing device, the yoke member is pressed against the rail member. Since a guide device is provided between the rail member and the yoke member to guide the ultrasonic transducer in the direction of conveyance while preventing separation between the two, the pressing force of the ultrasonic transducer against the rail member by the pressing device does not change. The guide device can guide the yoke member in accordance with the transport direction while preventing the yoke member from tilting in the moving direction, tilting in a direction perpendicular to the moving direction, and shifting in a direction parallel to the moving direction. can.

In this case, even if the conveyance path is curved, the yoke member can be suitably guided by the guide device regardless of the pressing force of the ultrasonic transducer against the rail member by the pressing device, so that the ultrasonic transducer A sufficient pressing force and thus a driving force can be ensured, and by obtaining a sufficient driving force, it is possible to suitably carry out transportation even if the conveying route is a steep uphill slope. Note that since the guide device is provided to prevent separation between the rail member and the yoke member, transportation is possible even on a vertical transportation path. Therefore, an ultrasonic conveyance device with no restrictions on the conveyance path is provided.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on the drawings.

1 to 3 are diagrams showing an example of an ultrasonic conveying device to which the present invention is applied, which includes a standing wave type ultrasonic motor as a driving source.

In those figures, reference numeral 10 denotes a base provided over a predetermined length, and on the upper surface of the base 10, a plate-shaped rail 1 extending in the longitudinal direction of the base IO is provided at the center in the width direction.
2 are fixedly installed, and a pair of guide rails 14. whose cross-sectional shape forms a substantially tangent H-shape on both sides of the rail 12.
14 are fixedly installed, and these guide rails 14
．． 14 allows the frame member 16 to be guided in the longitudinal direction of the base 10. Fitting portions 18 are fixedly provided at each corner of the surface of the frame member 16 on the base 10 side, and these fitting portions 18 are connected to the guide rail 14.1.
4 in the longitudinal direction and is fitted to the base 10 so as to be immovable in the direction toward and away from the base 10. In this embodiment, the base 10 and the rail 12 serve as a rail member, the frame member 16 serves as a yoke member, and the guide rail 14.
14 and each fitting portion 18 constitute a guide device.

A rectangular prism-shaped ultrasonic transducer 20 is disposed inside the frame-like member 16, and this ultrasonic transducer 20 is provided protruding from the surface located on the base 10 side at both ends in the longitudinal direction. It rests on the rail 12 in a pair of drives 22.22. The shape of the ultrasonic vibrator 20 is such that it bends and vibrates in the thickness direction (direction of approaching and separating from the rail 12) at both free ends in a secondary mode at a predetermined frequency, and at approximately the same frequency, both free ends vibrate in the length direction. It is predetermined to vibrate longitudinally in the first mode. In general, the resonance frequency of longitudinal vibration propagating in an elastic body depends on the length of the elastic body, and the resonance frequency of bending vibration in the thickness direction of the elastic body depends on the length and thickness of the elastic body. Therefore, it is easy to determine the shape of the ultrasonic transducer 20 as described above, and the details of the shape design of the ultrasonic transducer 20 are not necessarily necessary for understanding the present invention. Further explanation will be omitted.

On the surface of the frame member 16 opposite to the base 10 side, a holder 24 is provided so as to straddle the ultrasonic transducer 20 in the longitudinal direction.
is permanently installed. A male threaded member 26 is screwed into a female threaded hole formed in the longitudinal center of the holder 24.
From the holder 24 of this male threaded member 26 to the ultrasonic vibrator 20
A spring retainer 28 is screwed onto the sideward projecting portion. A leaf spring 30 is inserted between the spring holder 28 and the ultrasonic vibrator 20 with a predetermined preload. This results in
The drive unit 22.22 of the ultrasonic transducer 20 is pressed against the rail 12 according to the urging force of the leaf spring 30, and the urging force of the leaf spring 30 is adjusted appropriately by rotating the spring presser 28, thereby generating ultrasonic waves. The pressing force of the vibrator 20 against the rail 12 can be adjusted to a desired pressing force that provides a suitable driving force. Therefore, in this embodiment, the holder 24. m spring member 26° spring retainer 28. and the leaf spring 30 constitute a pressing device.

Rod-shaped members 32 and 32 are screwed and fixed to the center portions of both sides facing the width direction of the base lO of the ultrasonic transducer 20 so as to protrude in mutually opposite directions.
Engagement grooves 34, 34 are formed on the inner surface of the frame-like member 16 at positions corresponding to the rod-like members 32 and 32, respectively, and extend in the direction of approaching and separating from the base 10 and are open at both ends. Rod-shaped members 32, 32 are installed in the engagement grooves 34, 34.
are inserted into each. As a result, relative movement in the pressing direction of the leaf spring 30 between the ultrasonic transducer 20 and the frame member 16 is allowed, but the ultrasonic transducer 20
0 and the frame member 16 in the longitudinal direction of the base 10 is prevented due to the engagement of the rod members 32, 32 and the engagement grooves 34, 34. Therefore, in this embodiment, the rod-shaped member 32, 32 and the engagement groove 34 are
34 constitutes an engagement device. Note that the rod-shaped member 32
．． 32 is fixed to the ultrasonic transducer 20 at a location where the node of the standing wave due to the first-order longitudinal vibration mode overlaps the node of the standing wave due to the second-order bending vibration mode, that is, where the vibration amplitude is extremely large. is predetermined into small pieces.

A first piezoelectric body 38 on which an electrode 36 is integrally provided is fixed to the surface of the ultrasonic transducer 20 facing the rail 12, and a rod-shaped member 32, 32 of the ultrasonic transducer 20
Second piezoelectric bodies 42, 42, each having an electrode 40, 40 integrally provided thereon, are fixed to both side surfaces on which the electrodes 40, 40 are protruded. The electrode 36 of the first piezoelectric body 38 is connected to the alternating current '1' via an amplifier 44 whose amplification degree is variable and a phase shifter 46.
148, and the electrodes 40.40 of the second piezoelectric body 42.42 are connected to the alternating current voltage a48 via the amplifier 50 with variable amplification and the phase shifter 46. ing. Note that the ultrasonic vibrator 20 also serves as a ground electrode, and is grounded to the base 10 via, for example, a ground wire (not shown).

Next, the operation of the ultrasonic transport device configured as above will be explained.

First, an AC voltage of a predetermined frequency is applied from the AC power supply 48 to the first
When an AC voltage of the same frequency as the piezoelectric body 38 is applied to the second piezoelectric body 42, 42, the ultrasonic vibrator 20
resonates in the secondary mode of bending vibration to excite a standing wave, and vibrates in the primary mode of longitudinal vibration to excite a standing wave. Next, for example, as shown in FIG. .50, the ultrasonic transducer 20 generates substantially elliptical motion vibration of a predetermined shape, which is a combination of the first-order longitudinal vibration mode and the second-order bending vibration mode, and drives the ultrasonic transducer 20. Part 22.22 and rail 1
A driving force is generated between the two. That is, the ultrasonic transducer 2
For example, 0 is repeatedly deformed as shown in FIGS. 6(a) to 6(d), and in FIG. 6(a), when the longitudinal vibration of the ultrasonic transducer 20 is extended, the The drive unit 22 is brought into frictional contact with the rail 12 to generate a driving force in the direction indicated by A in the figure, and in FIG. 6(C), when the longitudinal vibration of the ultrasonic vibrator 20 contracts, The other driving portion 22 is brought into frictional contact with the rail 12 to generate a driving force in the direction indicated by A in the figure. The driving force thus generated causes the ultrasonic transducer 20 to move in the direction opposite to the direction A in FIGS. 6(a) and 6(C), and
Accordingly, the frame member 16 is moved in the same direction as the ultrasonic transducer 20 while being guided by the guide rails 14.14, and thus conveyance is performed. Note that the driving speed of the ultrasonic vibrator 20 can be adjusted as appropriate by changing the amplitude and phase of the AC voltage, and the driving direction of the ultrasonic vibrator 20 can be changed by changing the phase of the AC voltage. Can be done.

In the ultrasonic transport device configured as described above, the holder 24 serves as a pressing device for pressing the ultrasonic transducer 20 against the rail 12 fixed to the base 10. Male member 26. Spring retainer 28. and the leaf spring 30 is the frame member 1
6, and independent of the pressing device, a guide rail 14.1 serves as a guide device that guides the frame member 16 in a predetermined conveyance direction while preventing separation from the base 10.
4 and each fitting part I8 are provided between the base 10 and the frame-shaped member 16, so that the pressing force of the ultrasonic vibrator 20 against the rail 12 by the pressing device is not changed;
The guide device prevents the frame member 16 from tilting in the moving direction, tilting in a direction perpendicular to the moving direction (rolling in the B direction or C direction in FIG. 1), and preventing displacement in the direction parallel to the moving direction. At the same time, the frame member 16 can be guided in accordance with the transport direction. In this case,
Even if the conveyance path is curved, the leaf spring 3 of the pressing device
Regardless of the pressing force of the ultrasonic transducer 20 against the rail 12 due to the urging force of 0, the frame member 16 is
The ultrasonic transducer 20 can be guided suitably.
The pressing force on the rail 12 and the ultrasonic vibrator 20
It becomes possible to sufficiently secure the above-mentioned driving force, and by ensuring that the driving force is sufficiently secured, it is possible to suitably carry out the conveyance even if the conveyance route is a steep uphill slope. In addition, since the guide device is provided in such a manner as to prevent separation between the base 10 and the frame-shaped member 16, it is possible to secure a sufficient pressing force of the ultrasonic transducer 20 against the rail 12. Coupled with the fact that a frictional force between the sonic vibrator 20 and the rail 2 is suitably obtained, it becomes possible to carry out the conveyance even on a vertical conveyance path. Therefore, an ultrasonic conveyance device with no restrictions on the conveyance path is provided.

Further, according to this embodiment, the rod-like members 32 and 32 protruding from the ultrasonic transducer 20 are fitted into the engagement grooves 34 of the frame-like member 16 so as to be movable relative to each other in the pressing direction of the leaf spring 30. Since the rod-shaped members 32 and 32 are not fixed to the frame member 16, even when the ultrasonic transducer 20 is excited with a traveling wave, the rod-shaped members 32 and 32 are not fixed to the portion of the ultrasonic transducer 20 where the vibration amplitude is relatively small. If fixed, the operation of the ultrasonic transducer 20 can be made relatively stable, which has the advantage that a traveling wave type ultrasonic motor can be used as a drive source of the ultrasonic conveying device of the present invention.

In addition, in the above-mentioned embodiment, the ultrasonic transducer 20 has longitudinal vibration 1
Although we have explained that the driving force is generated by approximately elliptical motion vibration in which the next mode and the second bending vibration mode are at the base, it is not necessary to do so. The driving force may be generated by suitably combining various vibrations such as the above, and in these cases, it is also possible to use vibrations in higher-order modes of third or higher order.

Furthermore, in the above-mentioned embodiment, the device is constituted by the rod-shaped member 32.32 protruding from the ultrasonic transducer 20 and the retaining groove 34.34 provided in the frame-shaped member 16.
This is not necessarily necessary; for example, on the contrary, the engagement can be achieved by a pair of rod-like members protruding from opposing inner surfaces of the frame-like member 16 and engagement grooves provided on both sides of the ultrasonic transducer 20. The device may be configured, and the object that engages with the engagement groove does not have to be rod-shaped.

Further, in the above-described embodiment, the pressing device is configured with the leaf spring 30, but it may be configured with other springs other than the leaf spring, such as a coil spring or a helical spring.

Further, in the above-mentioned embodiment, the guide rail 14.14 has a U-shaped cross section, but the guide rail 14.14 has a U-shaped cross section. It may have a cross section other than the U-shape, for example, a U-shape, an L-shape, a three-C shape, a two-trapezoid shape, etc., as long as it can prevent separation from the table IO.

Further, in the above-mentioned embodiment, a part of the guide device is constituted by the guide rail 14.14 fixed on the base 10, but a cross section such as an inverted T-shape formed on the upper surface of the base 10 A part of the guide device may be constituted by a guide groove having the following. In this case, the frame member 16 is provided with a fitting portion having a shape corresponding to the guide groove.

Further, in the above-mentioned embodiment, the yoke member is constituted by the frame-like member 16, but this is not necessarily necessary, and for example, it may be constituted by a container-like member.

Furthermore, in the above embodiment, a rectangular flat piezoelectric element is used as the excitation body of the ultrasonic transducer, but this is not necessary, and other elements capable of converting electrical energy into mechanical energy, such as electrical A strain element, a magnetostrictive element, etc. may be used, and it is also possible to use various shapes other than a rectangular flat plate shape.

Further, in the above-mentioned embodiments, the ultrasonic conveying device is configured with a standing wave type ultrasonic motor, but it is not necessarily limited to this. In addition, it is also possible to configure the ultrasonic conveying device of the present invention using a laminated piezoelectric motor, a bimorph piezoelectric motor, or the like.

In addition, various changes may be made to the present invention without departing from the spirit thereof.

[Brief explanation of drawings]

FIG. 1 is a sectional view taken along line II in FIG. 2. FIG. 2 is a front view showing the main parts of the ultrasonic conveying device of the present invention, with a portion cut away. FIG. 3 is a plan view of the ultrasonic conveyance device shown in FIG. 2, with a portion thereof cut away. FIG. 4 is a block diagram showing a circuit for exciting the ultrasonic transducer of the ultrasonic transport device of FIG. 2. Fifth
The figure is a diagram showing an example of a voltage waveform applied to each piezoelectric body of the ultrasonic transducer of FIG. 2. FIGS. 6(a) to 6(d) are diagrams for explaining the operation of the ultrasonic conveying device shown in FIG. 2. 16: 20: (24: Sae. (32: Frame-shaped member (yoke member) Ultrasonic transducer holder, 26: Male member, 28: Spring press 30: Leaf spring) (Press device)

Claims (1)

[Claims] An ultrasonic transducer of the type that transports in a predetermined direction based on a driving force generated between an ultrasonic transducer that is vibrated ultrasonically and a fixed-position rail member that contacts the ultrasonic transducer. A sound wave conveying device, comprising: a yoke member; a pressing device provided on the yoke member to press the ultrasonic vibrator toward the rail member; a portion of the ultrasonic vibrator with a small vibration amplitude and the yoke; an engagement device provided between the ultrasonic transducer and the yoke member, which allows relative movement between the ultrasonic transducer and the yoke member in the pressing direction but prevents relative movement in the transport direction; An ultrasonic conveyance device comprising: a guide device provided between the yoke member and the guide device that guides the yoke member in the conveyance direction while preventing separation between the rail member and the yoke member.