Automatic machine for making stirrups and structural reinforcement

Claim 2

A machine for automatically making stirrups and like concrete reinforcements from rod, comprising: feed means for advancing a wire rod along a predetermined transport path; length-measuring means along said path displaceable in step with the displacement of said rod by said feed means for producing an output signal; cutoff means along said path for severing a length of said rod determined by said signal; bending means downstream of said cutoff means and actuatable to impart a selected degree of bend to said rod; programming means including a panel provided with switch means for operating said feed means, said cutoff means and said bending means in a predetermined sequence at least in part under the control of said output signal; and control means for automatically recycling said sequence.

Claim 3

The machine defined in claim 1 wherein said feed means comprises: a pair of calibrating rollers engageable with said rod at an upstream position of said path for imparting predetermined dimensions to the rod as the rod passes through said calibrating rollers; a pair of feed rollers frictionally engaging said rod downstream of said calibrating rollers along said transport path; a gear transmission coupling said pairs of rollers for joint rotation to advance said rod therethrough; a clutch having an input member connected with said transmission in one clutch position and disconnected from said transmission in another clutch position; a worm/worm-wheel arrangement operatively connected to said input member; and an electric motor connected to said arrangement; programming means including: a pneumatic control operatively connected to said clutch for shifting same between said position, and an electromagnetic air distributor pneumatically connected to said control.

Claim 4

The machine defined in claim 2 wherein said length-measuring means includes a terminal disc rotatable about an axis and formed with a multiplicity of contacts spaced therearound; a friction member gear-coupled to said transmission and spring-biased into frictional engagement with said disc for rotation thereof; an electromagnetic solenoid operatively connected with said friction member for drawing same out of engagement with said disc; and a contact finger sweeping the contacts of said disc for generating said output signal, each of said contacts being connected with corresponding terminals of said switch means.

Claim 5

The machine defined in claim 3 wherein said finger is secured to the upper end of a shaft coaxial with said disc, said length-measuring means further comprising a second solenoid for energizing same.

Claim 6

The machine defined in claim 4, further comprising a torsion spring acting upon said disc for restoring same to an initial position relative to said fingEr upon energization of the first-mentioned solenoid.

Claim 7

The machine defined in claim 4, further comprising a third solenoid operatively connected with said air distributor for admitting compressed air to said control and connected in circuit with at least one contact energized by said second solenoid, said bending means comprising: a bifurcated bending member rotatable about an axis generally transverse to said rod; angle-metering means operatively connected to said bending member for producing a second output signal in response to the angle of bend of the rod and connected with said programming means; and second clutch means operatively connected between said arrangement and said bending member for interconnecting said bending member and said arrangement in a first position of said second clutch means and disconnecting said arrangement from said bending member in a second position of said second clutch means, said second clutch means being energized at least in part by said third solenoid.

Claim 8

The machine defined in claim 6 wherein said angle-metering means comprises an angle-metering disc including a fixed ring having contacts at angularly spaced locations therealong corresponding to increments of bending of the rod; a brush carried by said member and adapted to wipe the contacts of said ring; and a helical spring bearing on said brush and of increasing extension as the relative angular displacement of said brush and said ring increases.

Claim 9

The machine defined in claim 7, further comprising means connecting each of the contacts of said ring with a respective terminal of said switch means.

Claim 10

The machine defined in claim 6 wherein said third solenoid upon deenergization, operates said electromagnetic air distributor to permit a member of at least one of said clutch means to slide downwardly and disengage the respective clutch while a corresponding member of the other clutch means is spring-biased into its position opposite that prior to deenergization of said third solenoid.

Claim 11

The machine defined in claim 8 wherein said distributor comprises six contact pairs arrayed along a circular path; a contact finger sweeping along said path and successively connecting the contacts of said pairs; a ratchet wheel operatively connected to said contact finger of said distributor; and means connecting one contact of each pair in circuit with said length-measuring means and another contact of each pair in circuit with said angle-measuring means.

Claim 12

The machine defined in claim 10 wherein said distributor further comprises a pawl cooperating with said ratchet for stepping same; a spring connected with said pawl for drawing same away from said ratchet; and a fourth solenoid operatively connected to said pawl for stepping said ratchet.

Claim 13

The machine defined in claim 3 wherein said cutoff means includes a guillotine-type shear for separating said rod; a cam shaft operatively connected with said shear for driving same; and means connecting said cam shaft with said arrangement in said other position of said clutch means for operating said shear.

Claim 14

The machine defined in claim 12, further comprising contacts closed upon operation of said shear, for stepping said distributor.