JPH0712329Y2 - Carrier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] The present invention relates to a transfer device using a piezoelectric element as a drive source.

[Prior Art] Conveying devices for reciprocally vibrating a horizontally arranged conveying member to convey relatively small articles in a certain direction are often used in factory production lines, and recently, Japanese Patent Application No. 60- 143109
Japanese Patent No. 3,058,036 discloses a type in which a piezoelectric element is used as a driving source.

This type of transfer device will be described. FIG. 3 shows the configuration of the transfer device. In the figure, 1 is a base, 2 and 2 are two sets of vibrating bodies,
3 and 3 are connecting leaf springs, and 4 is a carrier which is horizontally arranged above the base 1. The vibrating body 2 is called a bimorph type in which piezoelectric elements 6 made of piezoelectric ceramics are stacked and fixed on both surfaces of a leaf spring 5 having a linear shape. And
Each vibrating body 2, 2 is provided in a state of being raised with respect to the base 1, one end of a leaf spring 5 is fixed to the base 1, and a linear connecting leaf spring 3 is raised at the other end. It is installed in the closed condition. The connecting leaf springs 3, 3 support the carrier 4.

In this device, an alternating current is supplied from the power supply 7 to the piezoelectric elements 6, 6 of the vibrating bodies 2, 2 to excite them. Each exciter 2, 2 extends in a positive half cycle of an alternating current and contracts in a negative cycle. As a result, if the alternating currents applied to the vibrating bodies 2, 2 are shifted by half cycles, the vibrating bodies 2, 2 alternately and continuously bend to the right and left sides. The movement of each of the vibrating bodies 2, 2 is expanded by each of the connecting leaf springs 3, 3 and transmitted to the conveying body 4, and the conveying body 4 reciprocally vibrates in the direction A in the figure. Therefore, the articles 8 placed on the carrier 4 are sequentially transported in one direction.

This type of conveying device vibrates based on the principle described below. When the bending spring constant of the vibrator ₂ is K ₁ , the spring constant of the connecting plate spring 3 is K _2, and the mass of the carrier 4 is M, the vibration model is as shown in FIG. other
An alternating force of P ₀ sin ωt can be applied. Accordingly, the equation of motion of this system is expressed by the following equation, where K is the synthetic spring constant.

M ・ d ² x / dt ² + Kx = P ₀ sinωt (1) where P ₀ : maximum value of alternating force of the vibrating body ω: vibration angular frequency of the vibrating body (= 2πf, f: power supply frequency) K = K ₁ · K ₂ / K ₁ + K ₂ x: Displacement (perpendicular to the vibrating body) Therefore, the natural frequency of the system is Given in. Then, as shown in the diagram of FIG. 5, when the power frequency f is equal to the natural frequency fn, the carrier 4 is in a resonance state and a large vibration is obtained. Specifically, when the tip amplitude of the vibrating body is 10 μm due to the resonance state,
The carrier 4 is expanded to about 100 μm and vibrated.

(Problems to be solved by the invention) However, in the conventional transfer device configured as described above,
There are the following issues.

That is, as shown in FIG. 3, linear vibrators 2 and 2 are provided upright on the base 1, and further linear connecting leaf springs 3 and 3 are provided on the upper ends of the vibrators 2 and 2. It is mounted upright, the carrier 4 is supported by the connecting leaf springs 3, 3, and the drive system and the resonance expanding system are integrated. For this reason, the height from the surface of the base 1 to the carrier 4 is the sum of the total length of the vibrators 2 and 2 and the total length of the connecting leaf springs 3 and 3. For this reason, the carrier 4 is set at a relatively high position, which is inconvenient when the carrier device is combined with another machine such that the heights of the article carrier paths do not match.

In order to reduce the height from the base 1 to the carrier 4, the length of the connecting leaf springs 3,3 is made smaller, or the mounting height of the connecting leaf springs 3,3 to the vibrating body 4 is made smaller. However, the transfer device of this system is a system in which the spring constant of the connecting leaf springs 3, 3 is fixed and the power supply frequency of the alternating current flowing through the piezoelectric elements 6, 6 is adjusted to the spring constant of the connecting leaf springs 3, 3. Therefore, it is not possible to change the length and the mounting position of the connecting leaf springs 3, 3.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a carrier device in which the height from the base to the carrier is reduced and connection with a partner device is advantageous.

[Means for Solving the Problems] (Means for Solving the Problems) In order to achieve the above-mentioned object, the conveying device of the present invention vibrates the conveying body linearly by a vibrating body in which a piezoelectric element is in contact with an elastic plate. In a product for carrying an article placed on a carrier, a vibrating body is provided horizontally with its plate surface horizontal, and one end of an elastic plate of this vibrating body is fixed to a base and connected to this base. An elastic body is provided so as to be rotatable in the vertical direction, and one end of this connecting elastic body is attached to the other end of the elastic plate of the vibrating body, and the other end of the connecting elastic body is attached to a horizontally arranged carrier. It is a feature.

(Operation) With this configuration, one end of the connecting plate spring pivotally supported on the base is connected to the vibrator provided laterally on the base, and the other end of the connecting plate spring supports the carrier, Since the drive system from the vibrator to the pivot of the connecting leaf spring and the resonance expansion system from the pivot of the connecting leaf spring to the carrier are separated, the height from the base to the carrier is It only corresponds to the slight length from the pivotal part of the body to the upper end (the length of the standing part). Therefore,
The carrier can be set at a much lower position than the conventional one.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the carrying device of the present invention.

In the figure, 11 is a metal base. 12,12 are vibrators,
Each of these vibrating bodies 12, 12 is called a bimorph type in which piezoelectric elements 14, 14 made of piezoelectric ceramic or the like are mounted on both sides of a leaf spring 13 in an overlapping manner. Each vibrating body 12,12 is the base 1
It is placed horizontally on the upper side of 1, for example, arranged in series in a state of being horizontally arranged, and one end of the leaf spring 13 of each vibrating body 12, 12 is placed on the protrusion 11a, 11b formed on the upper surface of the base 11. Bolt 1
Fixed at 5. Reference numerals 16 and 16 denote connecting leaf springs.Each of these connecting leaf springs 16 and 16 is bent into a V shape, and a pivot support cylinder 17 is provided inside the bent portion along each direction in the width direction of the leaf spring. It is fixed. The connecting leaf springs 16 are provided in series on the upper side of the base with respect to the respective vibrating bodies 12, 12, and the pivots 18, 18 are attached to the pivot support cylinders 17 provided at the bent portions of the connecting leaf springs 16, 16. It is inserted and rotatably supported. The pivots 18, 18 are provided horizontally on the base 11 along a leaf spring width direction using a member (not shown). As a result, the connecting leaf springs 16 and 16 are rotatably supported by the base 11. And the connecting leaf springs 16,1
6 is a state in which one piece is positioned horizontally with the bent portion as a boundary and is connected and fixed to the other end of the leaf spring 13 of each vibrating body 12, 12 with a bolt 20, and the other piece is slightly inclined. Is standing up in. Reference numeral 19 denotes a flat carrier which is horizontally arranged above the base 11. The carrier 19 is supported by bolts 21 attached to the upper ends of the other pieces of the plate springs 16 and 16.

The carrier configured in this way is a base
11 is installed on the oiled surface, and is electrically connected to the piezoelectric elements 14 and 14 of the vibrating bodies 12 and 12, the base 11 and an AC power supply (not shown). An alternating current is applied to the piezoelectric elements 14, 14 of the vibrating bodies 12, 12 from an alternating current power source to excite them. Each of the exciters 12 and 12 expands in a positive half cycle of the alternating current and contracts in a negative cycle. As a result, if the alternating currents applied to the vibrating bodies 12, 12 are shifted by half a cycle, the vibrating bodies 12, 12 alternately and continuously bend upward and downward. The movement of the vibrating bodies 12, 12 causes the connecting leaf springs 16, 16 to move the vibrating bodies 1 about the pivots 18, 18.
The bending motion of 2 and 12 is expanded and it oscillates vertically. That is, as shown in FIG. 2, the connecting leaf springs 16 and 16 are located above the stationary position a in accordance with the motion of the vibrating bodies 12 and 12 and are located at the upper position b.
And rotates in the range of the lower position c. In this case, the connecting leaf spring
In 16 and 16, by setting the length from the pivotal support to the transporter connection larger than the length from the vibratory connection to the pivotal support, the vibration is generated as shown in Fig. 2. Body 12,1
The movement of 2 can be magnified by the connecting leaf springs 16,16. Then, the conveying body 19 reciprocally vibrates in the direction A in the figure by the rotational vibration of the connecting leaf springs 16, 16. Therefore, the articles 22 placed on the carrier 19 can be sequentially transported while being aligned in a certain direction.

The vibration action of this carrier will be described.

The vibration system based on the carrier 19 and the connecting leaf spring 16 has a natural frequency. (M: carrier mass, K: spring constant of connecting leaf spring from pivotal part to carrier). By adjusting the power supply frequency of the applied alternating current to the natural frequency fn, resonance of the vibration system occurs and the carrier 19 can obtain a large vibration as shown in FIG. As described above, the resonance state is determined by the spring constant of the connecting leaf spring 16 from the pivot portion to the carrier 19. Therefore, the portion of the connecting leaf spring from the pivot portion to the vibrating body 12 is set to have a short length, and the portion of the connecting leaf spring 16 from the pivot portion to the conveying body 19 is transmitted by transmitting the vibration of the vibrating body 12. It has a function of driving the system composed of, and does not have a geometric expansion function. Therefore, it is not necessary to consider the bending constant of the leaf spring 13 of the vibrating body 12 in the setting of the resonance frequency as in the conventional case, and simply the connecting leaf spring 16 from the pivot portion to the carrier body 19 is provided.
Setting of the resonance frequency and calculation can be performed by the spring constant of, and the design becomes easy.

Thus, the height of the carrier 19 in this carrier is substantially defined by the length of the connecting leaf spring 16 from the pivot supporting the resonance expanding system to the carrier 19, and the pivot supporting the drive system. The portion of the connecting leaf spring 16 from the to the vibrating body 13 is provided horizontally and does not enter the element that defines the height of the conveying body 19. Therefore, the height from the base 11 to the carrier 19 can be reduced by at least the length of the vibrating body 12 as compared with the conventional portion.

In the present invention, the leaf spring is used as the connecting elastic body that connects the vibrating body and the carrier, but the invention is not limited to this, and for example, a spring wire may be used.

[Advantages of the Invention] As described above, according to the transporting device of the present invention, one end of the connecting plate spring pivotally supported on the base is connected to the vibrating body provided laterally on the base to connect the connecting plate. Since the carrier is supported by the other end of the spring, the drive system from the vibrator to the pivot of the connecting plate spring and the resonance expanding system from the pivot of the connecting plate spring to the carrier are divided. The height from the base to the carrier can be suppressed to the length from the pivotal support part of the connecting leaf spring to the carrier, and therefore the height from the base to the carrier is much lower than in the past. It can be pressed down, the carrier can be set at a low position, and connection with the partner machine can be made without difficulty.

[Brief description of drawings]

FIGS. 1 and 2 show an embodiment of the present invention, FIG. 1 is a front view showing a carrying device, FIG. 2 is an explanatory view showing the movement of a connecting leaf spring provided in the carrying device, and FIG. FIG. 4 shows a conventional example, FIG. 3 is a front view showing a transfer device, FIG. 4 is a view showing a vibration model of the transfer device, and FIG. 5 is a typical resonance in a piezoelectric element drive type transfer device. It is a figure which shows a curve. 11 ... Base, 12 ... Exciter, 13 ... Leaf spring, 14 ... Piezoelectric element, 16
… Leaf springs for connection.

Claims (1)

[Scope of utility model registration request] 1. A vibrating body in which a piezoelectric element is in contact with an elastic plate vibrates a carrier to convey an article placed on the carrier. The vibrating body is laterally arranged with its plate surface horizontal. It is provided on a stand, and one end of the elastic plate of this vibrator is fixed to the base,
Moreover, a connecting elastic body is provided on the base so as to be vertically rotatable,
A conveying device in which one end of the connecting elastic body is attached to the other end of the elastic plate of the vibrating body, and the other end of the connecting elastic body is attached to the horizontally arranged conveying body.