US 2004/0102858 A1Published application

Soft-touch gripping mechanism for flat objects

OwnerBoris Kesil, Elik Gershenzoninventors

Life of this patent

Estimating the term…

Loading patent…

Abstract

A soft-touch gripping mechanism of the invention contains three gripping fingers arranged circumferentially around a circular flat object such as, e.g., a semiconductor wafer. The soft-tough force applied to the wafer from the gripping posts on the ends of the gripping fingers is controlled from a common force measurement sensor, e.g., a special position sensor that consists of a moveable magnetic flag attached to a pusher plate on the end of the output shaft of a linear stepper motor and a sensitive member, e.g. a Hall sensor chip that responds to the position of the magnetic flag. The Hall sensor produces an output voltage signal that is proportion to the position of the flag relative to the Hall sensor chip. The sensor is connected to a controller that also controls operation of the aforementioned linear stepper motor. The soft touch is achieved by transmitting the movement of the pusher to the linear fingers through a spring. In order to facilitate insertion of the distal finger into narrow slots between the flat objects, such as semiconductor wafers in the storage cassette, the distal post can be turned by an angle less 90°. Reduced rotary sliding movement minimizes a chance of contamination of the wafer with products of wear.

Claims24

Dependent claims

A precision soft-touch gripping mechanism for flat objects having a peripheral edge, said mechanism comprising:

a flat gripper body having an upper surface, a lower surface and
attachable to an external manipulation means;
at least one longitudinal gripping finger in the form of an elongated member having a distal end and a proximal end, said distal end supporting at least one distal gripping post;
a first side gripping finger comprising a lever of the second order pivotally installed on said gripper body and having a first arm and a second arm, said first arm supporting at least one second side gripping post, and said second arm having a first guide slot;
a second side gripping finger comprising a lever of the second order pivotally installed on said gripper body and having a third arm and a forth arm, said third arm supporting at least one third side gripping post, and said second arm having a second guide slot;
a pin that is rigidly attached to said proximal end of said at least one longitudinal gripping finger and is guided in said first guide slot and in said second guide slot simultaneously;
a moveable frame that rigidly supports said pin and is moveable in the direction of said at least one longitudinal gripping finger, said frame having a first end face nearest to said pin and a second end face opposite to said first end face;
linear drive means having an output shaft that supports pushing member;
a flexible member between said pushing member and said second end face of said frame;
and
gripping force control means common for said at least one longitudinal gripping finger, said first side gripping finger, and said second side gripping finger for controlling a final soft-touch gripping force applied from said at least one distal gripping post, said second side gripping post, and said third side gripping force to said periphery edges of said flat objects via said flexible member.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/719,411Filed 24 Nov 2003
Priority: 4 Sep 2001
Published: 27 May 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

B25J 9/1633
Characterised by the control loop: compliant, force, torque control, e.g. combined with position control
G05B 2219/37003
Measurements: detect if no workpiece in holder
G05B 2219/39505
Robotics, robotics to robotics hand: control of gripping, grasping, contacting force, force distribution
B25J
Manipulators

Family

Application09/944,605Continuation in part · filed 4 Sep 2001
Application10/719,411Continuation in part · filed 24 Nov 2003
US 2003/0130759 A1Published application
US 7,140,655 B2Related patent
US 2004/0102858 A1This patent

From the US filing history. Foreign family members aren’t listed.