초록 ▼

Sensors associated with load carrying members are inaccurate, incorrectly sense the position of the load, and are subject to impact forces which cause premature sensor failure. A load lifting device having a load carrying member and first and second sensors and first and second reflectors on the loa

Sensors associated with load carrying members are inaccurate, incorrectly sense the position of the load, and are subject to impact forces which cause premature sensor failure. A load lifting device having a load carrying member and first and second sensors and first and second reflectors on the load carrying member is provided. The sensors are mounted on a first end portion of load carrying member at longitudinally spaced apart locations and the first and second reflectors are mounted on a second end portion of the load carrying member at spaced apart locations on the second end portion. The first sensor delivers a first signal to the first reflector and receives a reflection of the first signal, and the second sensor delivers a second signal to the second reflector and receives a reflection of the first signal from the second reflector. The problems associated with inaccurate sensing of load position, damage to the sensors by impact, and premature wear due to cyclical forces are substantially reduced. The load lifting device is particularly suited for use on a material handling vehicle of the automatic guided vehicle type.

대표청구항 ▼

A load lifting device, comprising: a load carrying member having a first end portion and a second end portion extending outwardly from said first end portion; a first sensing means for delivering a first signal from a first sensing location adjacent said first end portion and receiving a reflection

A load lifting device, comprising: a load carrying member having a first end portion and a second end portion extending outwardly from said first end portion; a first sensing means for delivering a first signal from a first sensing location adjacent said first end portion and receiving a reflection of said first signal; a second sensing means for delivering a second signal from a second sensing location adjacent said first end portion and receiving a reflection of said second signal, said second sensing location being positioned at a lower elevation than said first sensing location; a first reflecting means for receiving said first signal at a first reflecting location adjacent the second end portion and delivering a reflection of said first signal in a direction toward said first sensing means; a second reflecting means for receiving said second signal at a second reflecting location adjacent the second end portion and delivering a reflection of said second signal in a direction toward said second sensing means, said first and second reflecting location being spaced from one another, said sensing and reflecting means being free from contact with a load carried on the load carrying member and providing accurate sensing of the position of the load on the load carrying member.