To easily adjust a tip arm angle.

A main shaft 46a of a motor 46 is fixed to a gear 74, and meshes with its gear 74, a gear 62, a bevel gear 58 and a bevel gear 68 in this order, and a support pin 66 to support a support body 64 is fixed to the bevel gear 68. Therefore, when the motor 46 is driven, a latitudinal directional angle of an arm 22 connected to the support body 64 and a sleeve 18 can be changed. On the other hand, a main shaft 76a of a motor 76 is fixed to a gear 80, and meshes with its gear 80, a gear 82 and a gear 50 in this order, and a rotary body 54 is fixed to the gear 50. Therefore, when the motor 76 is rotated, a longitudinal directional angle of the arm 22 connected to the rotary body 54 and the sleeve 18 or the like can be changed. In this way, a solid angle (an arm angle) to show the direction of the tip of the arm 22 can be easily adjusted.