JPH0242660Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a piezoelectric parts feeder, and in particular, to a piezoelectric parts feeder using a piezoelectric element using a piezoelectric constant d ₃₁ .

[Prior Art] Piezoelectric parts feeders have attracted attention in recent years because they have advantages over electromagnetic parts feeders, such as superior responsiveness, the ability to drive with low energy, and being small and lightweight.

Conventionally, this type of piezoelectric parts feeder
The one shown in Figure 6 was found. That is, base 1
At the top, two bimorphs 2 are given an inclination angle θ and their lower ends are supported, and a vibrating conveyance plate 3 is horizontally supported at the upper end of the bimorphs 2. Bimorph 2 is
A bent piezoelectric element 5 is attached to both sides of a spring plate 4.

With the above configuration, when an AC voltage is applied to the bimorph 2 from the power supply 6, bending vibration is generated in the bimorph 2, and the conveyed object 7 placed on the vibrating conveyance plate 3
is sent from a to c in one cycle of the driving voltage.

[Problems to be solved by the invention] The conventional piezoelectric parts feeder as described above is
Since the bimorph 2 is installed upright on the base 1, there are problems in that the height is large and the space occupied is large.

This invention is an attempt to solve this problem, and aims to obtain a piezoelectric parts feeder that can have a small finished height and a small volume.

[Means for Solving the Problems] The piezoelectric parts feeder according to this invention has a substrate that vibrates in the vertical direction and a drive piece that forms a fixed angle with the substrate to form an integrated metal base, and bends the substrate. The tip of the driving piece of the piezoelectric unit, which is formed by pasting a piezoelectric plate for the purpose of the present invention, is engaged with the conveying body.

[Function] In this invention, when the piezoelectric plate causes bending vibration in the substrate, the tip of the drive piece vibrates obliquely and sends the carrier in a fixed direction.

[Example] Figures 1 to 3 show an example of this invention,
FIG. 1 shows a piezoelectric unit U, in which a metal base 11 integrally formed of metal includes a substrate 13 to which a piezoelectric plate 12 consisting of a d ₃₁ mode element is attached and vibrates in the vertical direction; It forms an L-shape with the drive piece 14 that vibrates in the transverse direction at right angles. Board 13
A mounting hole 15 is provided at the end.

In the piezoelectric unit u having the above configuration, one end is fixed by the mounting hole 15, and when the substrate 13 is vibrated in the vertical direction by the piezoelectric plate 12, the upper end of the drive piece 14 is approximately circular with the mounting hole 15 as the center. This results in an arc-shaped vibration.

Figures 2 and 3 show a rotary parts feeder using three piezoelectric units u as described above, with a base 16
A single upper plate 17 is placed on the upper ends of the three piezoelectric units u attached to the. The lower surface of the base 16 is supported by a lower plate 19 via a vibration-proofing rubber 18. A bowl 20, which is a carrier, is placed on the upper plate 17. A cover 21 is attached to the side of the base 16. A recess 22 for housing the substrate 13 of the piezoelectric unit u is formed on the lower surface of the base 16, and the base 16 and the upper plate 1
A groove 23 for accommodating the drive piece 14 of the piezoelectric unit U is formed continuously in the recess 22 through the groove 7 . The piezoelectric unit u is fixed to the base 16 by a fixture 24 inserted into the mounting hole 15. The upper end of the drive piece 14 is fixed to the top plate 17 by screws or engaged with the bowl 20 by a connecting means 25 such as a bearing. 26 is a fixed part of the parts feeder.

With the above configuration, when an electric signal is applied to the piezoelectric plate 12 to cause a bending motion, the substrate 13 vibrates up and down centering on the mounting hole 15, and accordingly, the drive piece 14 moves around the mounting hole 15. Circular vibration is performed with the center as the center. As a result, the bowl 20 is rotationally displaced. The substrate 13 may be tapered to become thinner at the tip.

Further, the resonant frequency of the bowl 20 is determined by adjusting the length and thickness of each side of the substrate 13 and the drive piece 14, and is generally set between 50 and 300 Hz.

As described above, the structure in which the driving piece 14 passes through the base 16 and the upper plate 17 has the advantage that the device can be made extremely thin.

FIG. 4 shows a piezoelectric unit according to another embodiment, in which the substrate 28 of the metal base 31 to which the piezoelectric element 27 is attached extends to both sides of the driving piece 29 to support it at two points. It is held between rollers 30 at both ends.

With the above configuration, the piezoelectric plate 27 causes the substrate 28 to
vibrates, and the tip of the driving piece 29 displaces the carrier.

FIG. 5 shows another embodiment of a piezoelectric unit, in which a metal base 32 has a driving piece 34 integrally connected to a substrate 33 at an angle. Piezoelectric plates 35 are attached to both sides of the substrate 33. Board 33
It is appropriate that the angle φ between the drive piece 34 and the drive piece 34 is 45° or less.
With this configuration, the piezoelectric unit can be made even thinner.

Note that by providing a suitable feedback terminal on the piezoelectric plate and exciting the piezoelectric plate with a drive power source that causes self-excited vibration, the piezoelectric unit can always be operated at the resonance point.

Furthermore, although the above embodiment shows the case where the conveyor is rotated, a plurality of piezoelectric units can be arranged in a straight line and conveyed in a straight line. Further, the number of piezoelectric units may be appropriately selected depending on the specifications of the parts feeder.

[Effects of the invention] As described above, this invention has a plurality of piezoelectric units each consisting of a substrate to which a _d31 mode piezoelectric plate is attached and vibrates in the vertical direction, and a driving piece provided on this substrate. The drive unit is arranged linearly or concentrically and applies linear or rotational displacement to the carrier placed on the upper end of the drive piece via a connecting means, reducing the height of the drive unit and occupying less space. It has the effect of being able to reduce the size of the image.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of this invention,
1 is a partial perspective view, FIG. 2 is a side view, and FIG. 3 is a sectional view taken along the line - in FIG. 2.
4 and 5 are partial side views of other embodiments, respectively. FIG. 6 is a perspective view of a conventional piezoelectric parts feeder. u... Piezoelectric unit, 11, 31, 32... Metal base, 12, 27, 35... Piezoelectric plate, 13,
28, 33... Board, 14, 29, 34... Drive piece, 15... Mounting hole, 20... Bowl (carrier),
25...Connector.

Claims (1)

[Claims for Utility Model Registration] (1) A piezoelectric plate for bending motion attached to the substrate of a metal base consisting of a substrate for longitudinal vibration and a driving piece integrally formed with this substrate at a certain angle. What is claimed is: 1. A piezoelectric parts feeder comprising: a piezoelectric unit comprising: a piezoelectric unit; and a connecting means for engaging a tip end of the drive piece with a carrier. (2) The piezoelectric parts feeder according to claim 1, which includes a plurality of piezoelectric units arranged either linearly or concentrically.