JPH06344281A - Micro gripper - Google Patents

Abstract

(57) [Summary] [Construction] In a micro gripper having two fingers 1 capable of sandwiching and gripping a fine target object, in a gripping surface 11 of the finger 1 in contact with the fine target object, or a heater part near the gripping surface 11. It is equipped with 8. [Effect] It is possible to smoothly operate a lightweight fine object of milligram order or less.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a micro gripper used for assembling fine parts and grasping fine organic substances.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 2, a contact-type micro gripper for holding or sucking a fine object such as a fine component or a fine organic substance is held by a pair of fingers 1 and 1. 1. An enlarging mechanism 2 using a spring joint 21 for enlarging the displacement in the direction perpendicular to the longitudinal direction of 1, a laminated piezo actuator 3 for opening and closing the fingers 1 via the enlarging mechanism 2, and a pair of enlarging mechanism 2 2 is constituted by a fixed base portion 4, and by extending the piezo actuator 3, the fingers 1 and 1 are closed to hold a fine object 5 which is an object of the order of several tens of microns. (For example, published by Nikkan Kogyo Shimbun, magazine "Machine Design", Vol. 34, No. 15, 1990,
66 pages, Proceedings of the 2nd Bioengineering Symposium, Japan Society of Mechanical Engineers (No920-7),
Pp. 117-118, Jan. 30, 1992). With this micro gripper, several meters
It is known that a force of about N can be generated, and that it has sufficient performance as a force for grasping a fine component.

[0003]

However, in the prior art, when the weight of the fine object to be manipulated is reduced,
Due to the surface tension of the moisture or liquid adhering to the surface of the fine object or the finger supporting the fine object, or the adhesive force between the fine object and the finger due to the dispersion force,
There was a problem that smooth operation was not possible. That is, this adhesive force, when converted to weight, is 2 to 4 mg,
When the weight of the fine object is more than this, the fine object adheres to the fingers and cannot be separated due to the adhesive force, so that the fine object cannot be smoothly operated. It is an object of the present invention to provide a micro gripper that enables a fine object to be easily separated from the surface of a finger and that allows a smooth gripping operation.

[0004]

In order to solve the above problems, the present invention relates to a micro gripper provided with two fingers capable of sandwiching and gripping a fine object, and a gripping of the finger in contact with the fine object. The heater is provided on the surface or in the vicinity of the grip surface. The gripping surface is a polymer containing at least carbon atoms and fluorine atoms.

[0005]

When the resistance wire of the heater is energized by the above means, the resistance wire generates heat to heat the gripping surface of the finger, the liquid adhering to the gripping surface evaporates, and the liquid between the fine target object and the finger is evaporated. Adhesion is reduced. Therefore, the fine object is easily separated from the surface of the finger, and the operation of the fine object is facilitated.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a finger according to an embodiment of the present invention. In addition, as shown in FIG.
A pair of fingers 1, a magnifying mechanism 2 using a spring joint 21 that magnifies the displacement of the finger 1 in the direction perpendicular to the longitudinal direction, and a laminated piezoelectric actuator 3 that opens and closes the finger 1 via the magnifying mechanism 2. The configuration including the base 4 to which the enlargement mechanism 2 is fixed is basically the same as the conventional one. It differs from the conventional one in the following points. That is, in the first embodiment,
As shown by the dotted line in FIG. 1, a zigzag-shaped platinum foil resistance wire 6 is provided on the gripping surface 11 of the finger 1 which is in contact with the fine object 5, and the resistance wire 6 is wrapped in a quartz insulating thin film 7 in a sandwich shape to provide insulation. The thin film 7 is fixed so as to be the surface of the grip surface 11. A direct current or an alternating current is applied to the resistance wire 6, and the resistance wire 6 constitutes a heater portion 8. When the resistance wire 6 is energized, the resistance wire 6 generates heat and the gripping surface 11 of the finger 1 is heated, the liquid adhering to the gripping surface 11 evaporates, and the adhesive force between the fine object and the finger decreases. . In fact, when a DC voltage of 10 V was applied to the resistance wire 6 of platinum foil having an electric resistance of about 200 ohms, it was confirmed by the infrared micro-image thermometer that the finger 1 was heated to about 85 ° C. When the fine object 5 was gripped by the finger 1 in this state, the adhesive force was about 0.5 to 0.8 mg in terms of weight. Although the resistance wire 6 is fixed to the gripping surface 11 in the above-described embodiment, the position where the resistance wire is provided is not limited to the gripping surface as long as it is close to the portion in contact with the minute object, and similar results can be obtained. In the second embodiment, a polytetrafluoroethylene film is used as the insulating thin film 7 that covers the resistance wire. In this case, when the finger 1 was heated to about 85 ° C. by the heater unit 8, the adhesive force between the fine object and the finger was about 0.1 to 0.4 mg in terms of weight. That is, the insulating thin film 7 covering the grip surface 11
Shows that polytetrafluoroethylene is superior to quartz in terms of reducing the adhesive strength. It is considered that this is because polytetrafluoroethylene is superior in water repellency to quartz, and thus the residual adsorbed water was small. In this embodiment,
An example using polytetrafluoroethylene was explained, but if it is a fluorine-based polymer containing at least carbon atoms and fluorine atoms, it is superior in water repellency as compared with quartz, so similar results can be obtained. .

[0007]

As described above, according to the present invention, the finger is provided with the heater portion to remove the liquid between the finger and the fine object to reduce the adhesive force between the finger and the fine object. As a result, there is an effect that it is possible to smoothly operate a light microscopic object of milligram order or less, which cannot be smoothly operated by the conventional micro gripper.

[Brief description of drawings]

FIG. 1 is a perspective view showing a finger according to an embodiment of the present invention.

FIG. 2 is a front view of a micro gripper.

[Explanation of symbols]

 1 Finger 11 Gripping Surface 5 Fine Object 6 Resistance Wire 7 Insulating Thin Film 8 Heater Part

Claims (2)

[Claims] 1. A micro gripper provided with fingers capable of gripping and grasping a fine target object, wherein a heater portion is provided on a gripping surface of the finger which is in contact with the fine target object or in the vicinity of the gripping surface. Micro gripper. 2. The micro gripper according to claim 1, wherein the gripping surface is a polymer containing at least carbon atoms and fluorine atoms.