Vibrating screed and curb-forming apparatus

Claim 1

A lightweight, portable, concrete speed comprising: (a) a base screed unit including: (i) an elongated open frame structure comprising at least one integral frame unit and if more than one a group of interconnected separable integral open frame units and having fixedly mounted on said structure and extending for the length thereof a plurality of parallel, spaced apart screed plates for engaging and leveling concrete as the screed is moved over the concrete; (ii) a base unit vibrating element comprising a base unit semi-flexible shaft rotatively supported in said frame structure and extending for the length thereof and having means operatively associated with said base unit shaft enabling said base unit shaft when driven to impart vibrations to said frame structure and throughout the length of each of said screed plates; and (iii) drive means mounted intermediate the ends of said base screed unit and connected to drive said base unit shaft to impart said vibrations to said base unit frame structure and said plates; and (b) a pair of lightweight, portable and detachable auxiliary combined screed and curb-forming units, each comprising: (i) an elongated integral open frame structure adapted to mate the open frame structure of said base screed unit and having fixedly mounted on said auxiliary unit frame structure and extending for the length thereof a plurality of parallel, spaced apart auxiliary screed plates mating those on said base screed unit for engaging and leveling concrete for a portion of the length of the auxiliary unit as an extension of the length engaged and leveled by said base unit screed plates and having operatively associated with said auxiliary screed plates curb-forming plate means for supporting the screed at both ends thereof and for engaging the concrete and for the remaining portion of the length of the auxiliary unit forming a curb as an extension of the length engaged and leveled by said auxiliary screed plates; (ii) means for detachably connecting adjacent end portions of said base unit and auxiliary unit open frame structures in a predetermined angular relationship; (iii) a hopper mounted on said auxiliary unit frame structure having an open top and an open bottom extending through said curb-forming means; (iv) first vibratory means operative in association with said base unit shaft being driven to impart vibrations to said auxiliary unit structure and screed plates; and (v) second vibratory means operative in association with said base unit shaft being driven to cause any concrete mix placed in said hopper to be vibrated during forming of said curb; whereby when said drive means on said base unit operates and rotates said base unit shaft, said pair of auxiliary combined screed and curb-forming units mounted at the ends of said base unit are enabled to simultaneously level the concrete and form curbs at both ends of said base unit simultaneous with said base unit screeding the concrete therebetween.