Vacuum apparatus

Abstract

A vacuum apparatus includes a body, a dust-collecting box, a fan and a detection unit. The dust-collecting box is located inside the body. The fan is located inside the by closing to the dust-collecting box. The detection unit located around a pipe-end opening of the body further includes a detection assembly and a lens assembly. The detection assembly has an infrared emitting element and an infrared receiving element. The lens assembly has a first lens and a second lens, located to opposing sides of the pipe-end opening. The first lens has a first cutout, and the second lens has a second cutout. The infrared ray emitted by the infrared emitting element penetrates both the first cutout and the second cutout, and is finally received by the infrared receiving element.

What is claimed is: 
     
         1 . A vacuum apparatus, comprising:
 a body, having a pipe-end opening communicatively with the atmosphere;   a dust-collecting box, located inside the body, having a dust-sucking pipe, the dust-sucking pipe further having a first end and a second end opposing to the first end, the first end being positioned inside the dust-collecting box while the second end extends out of the body through the pipe-end opening;   a fan, located inside the body at a place beside the dust-collecting box; and   a detection unit, located around the pipe-end opening, further including a detection assembly and a lens assembly, the detection assembly having an infrared emitting element and an infrared receiving element, the lens assembly has a first lens and a second lens located individually to opposing sides of the pipe-end opening, respectively, a front end of the first lens being formed to have a first cutout while another front end of the second lens is formed to have a second cutout facing the first cutout, the first lens including thereinside the infrared emitting element, the second lens including thereinside the infrared receiving element, the infrared emitting element being to emit an infrared ray to penetrate the first cutout and the second cutout and finally to the infrared receiving element.   
     
     
         2 . The vacuum apparatus of  claim 1 , wherein spacing between the first cutout and the second cutout is measured to be a first distance at an exterior side of the lens assembly, while another spacing between the first cutout and the second cutout is measured to another second distance at an interior side of the lens assembly, wherein the first distance is larger than the second distance. 
     
     
         3 . The vacuum apparatus of  claim 1 , wherein the spacing between the first cutout and a centerline of the pipe-end opening is tapered. 
     
     
         4 . The vacuum apparatus of  claim 1 , wherein the spacing between the first cutout and a centerline of the pipe-end opening is tapered. 
     
     
         5 . The vacuum apparatus of  claim 1 , wherein the infrared emitting element is parallel to the infrared receiving element, wherein the infrared ray emitted by the infrared emitting element penetrates both the first cutout and the second cutout and then is received by the infrared receiving element.