Capacitance type load sensor

A capacitance load sensor, comprising:

• a first electrode;
• a second electrode disposed to face said first electrode and to be spaced therefrom and cooperating with said first electrode to form a capacitor;
• first and second holding members made of an insulating material, said first and second holding members supporting said first and second electrodes for relative motion in the direction along which a facing area between said electrodes changes, with a distance between said electrodes kept constant;
• an elastic member having opposite end portions thereof associated with said first and second holding members, respectively, said elastic member being elastically deformable in the direction of the relative motion between said first and second electrodes,
• wherein load to be measured by the load sensor is applied to said first and second holding members or to said elastic member,
• wherein said first and second electrodes are each formed into a hollow cylinder shape which is open at its opposite end faces,
• wherein said first holding member is comprised of a hollow outer tube having a peripheral wall and an end wall formed integrally therewith at one end of the peripheral wall,
• wherein said second holding member is comprised of a hollow inner tube disposed in the hollow outer tube and having a peripheral wall and an end wall formed integrally therewith,
• wherein said outer and inner tubes are arranged for relative motion along a longitudinal axis of said load sensor,
• wherein said first electrode is attached to the inner peripheral face of the peripheral wall of the outer tube, and
• wherein said second electrode is attached to the outer peripheral face of the peripheral wall of the inner tube.