Screwdriver device and screw

Abstract

A screwdriver device where rotational torque directly applied to the device by an external force can be drastically reduced in screw tightening operation. The screwdriver device has characteristic construction means having a device body (1) and a male-type head section (21). The device body (1) is constructed by layering over each other piezoelectric elements (3, 4) in a screwdriver device (alpha2), the piezoelectric elements (3, 4) generating predetermined ultrasonic vibration with application of a predetermined AC voltage, and based on the ultrasonic vibration, the device body (1) excites mechanical vibration in a predetermined direction on a vibration end surface (1a) of the device body (1). The male-type head section (21) is formed so that it can fit in a female-type engraved marking (103) in a screw (beta1) and is integrally fixed with the device body (1) on the vibration end surface (1a) of the device body (1). The male-type head section (21) applies rotational torque, directly applied to the screwdriver device (alpha2) by an external force, to the screw (beta1) in which the female-type engraved marking (103) is fitted and contact, and also the male-type head section (21) transmits to the screwdriver device (alpha2) mechanical vibration in a predetermined direction excited by the device body (1).

Description

technical field [0001] The invention relates to a screw turning device for fastening or loosening a screw, and a screw corresponding thereto. [0002] This application is based on Japanese Patent Application No. 2004-013184 filed on January 21, 2004, Japanese Patent Application No. 2004-067207 filed on March 10, 2004, and Japanese Patent Application No. 2004 filed on May 18, 2004 -147113 and Japanese Patent Application No. 2004-237880 filed on August 18, 2004 claim priority, and the contents thereof are incorporated herein. Background technique [0003] Conventionally, screws have been widely used as a joining mechanism for parts. As a mechanism for fastening such a screw, the following mechanism is generally used in the past. The top of the screw is formed with a concave mark such as a "cross hole" in the shape of a plus sign (+) or a "slotted groove" in the shape of a minus sign (-), By fitting and rotating the tip of a screw driving device such as a correspondingly form...

AI Technical Summary

Problems solved by technology

In addition, when the number of screws to be fastened is large, or the parts for fastening the screws are hard, etc., very large physical strength is required, or a very large load such as electric power is required.

[0009] On the other hand, there are problems such as the following in mechanical products and the like constituting exterior structural parts by screwing: since the top of the screw head is naturally exposed on the surface, it may be damaged due to the concave marking or setting provided on the top of the screw head. Fastening mechanisms such as claws on the peripheral side seriously damage the overall appearance of the mechanical product

[0010] Furthermore, for screws fastened to structural parts (parts to be fastened), if there is a screw driving device whose end shape corresponds to the fastening mechanism, it can be easily loosened. It is extremely inappropriate if the screw tightened in the normal process is loosened by a third party, and there will be a problem (for example, when the product guarantee condition is that no screw loosening operation has been performed)

[0011] Furthermore, there is also the following problem: if the mechanical product constructed by screw joint is used for a long time, the screw will loosen naturally

[0014] However, when tightening a screw simply by pressing a piezoelectric screwdriver against the top of the screw without markings, it may be difficult to obtain a sufficiently high tightening force, and a higher tightening force is required for reliable screw tightening.

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