Draw-bending machine

• US 20030061853A1
• Filed: 09/17/2002
• Published: 04/03/2003
• Est. Priority Date: 10/02/2001
• Status: Active Grant

• Current Assignee: Fabbrica Macchine Curvatubi Crippa Agostino SPA
• Original Assignee: Fabbrica Macchine Curvatubi Crippa Agostino SPA
• Inventors: Crippa, Aurelio
• Granted Patent: US 6,694,794 B2
• Time in Patent Office: Days
• US Class Current: 72/307
• CPC Class Codes: B21D 7/024 by a swinging forming member
• CPC Class Codes: B21D 7/12 with programme control
• CPC Class Codes: B23Q 7/04 by means of grippers B23Q7/1494 takes precedence

Abstract

A draw-bending machine comprises a base frame (2), a bending head (3) movably in engagement with the base frame (2), a support and positioning device (9) for the bending head (3), and handling and locking means (51) of a pipe (6) to be bent. The support and positioning device (9) consists of a first support arm (10) movable relative to the base frame (2) and a second support arm (17) having a first end (17a) hinged on an end (10a) of the first support arm (10) and a second end (17b) hinged on the bending head (3). The handling and locking means (51) comprises a first gripping unit (25) adapted to shift the pipe (6) to an operating space that can be reached by the bending head (3).

Claims

1. A draw-bending machine comprising:

a base frame (2);

a bending head (3) movably in engagement with the base frame (2) and including at least one bending die (4) rotatable about a bending axis (Z);

a support and positioning device (9) of said at least one bending head (3), said support and positioning device (9) being linked to the base frame (2);

handling and locking means (51) for a pipe (6) to be bent;

the support and positioning device (9) of said at least one bending head (3) presenting;

a first support arm (10) movably in engagement with the base frame (2), said first support arm (10) having a first end (10a) and a second end (10b) opposite to the first one (10a);

first actuating means (11) of the first support arm (10);

second actuating means (12) of the first support arm (10);

a second support arm (17) having a first end (17a) hinged on the first end (10a) of the first support arm (10) at a first articulation axis (J) and a second end (17b) hinged on the bending head (3) at a second articulation axis (K);

third actuating means (18) of the second support arm (17) around the first articulation axis (J);

fourth actuating means (19) of the bending head (3) around the second articulation axis (K);

the draw-bending machine being characterized in that the handling and locking means (51) for the pipe (6) to be bent comprises a first gripping unit (25) having a first (27) and a second (28) clamps aligned along a first alignment direction (P) to tighten the pipe (6) to be bent at two regions spaced apart from each other.

2. The draw-bending machine as claimed in claim 1, wherein the first support arm (10) is movable relative to the base frame (2) along a first translation direction (X) and along a second translation direction (Y) perpendicular to the first one (X).

3. The draw-bending machine as claimed in claim 2, wherein the first actuating means (11) of the first support arm (10) is operatively active along the first translation direction (X) and the second actuating means (12) of the first support arm (10) is operatively active along the second translation direction (Y).

4. The draw-bending machine as claimed in claim 2, wherein the first translation direction (X) is horizontal to the resting surface of the base frame (2) and the second translation direction (Y) is vertical to the resting surface of the base frame (2).

5. The draw-bending machine as claimed in claim 1, wherein the second articulation axis (K) is parallel to the first articulation axis (J).

6. The draw-bending machine as claimed in claim 2, wherein said first (J) and second (K) articulation axes are perpendicular to both the first (X) and second (Y) translation directions.

7. The draw-bending machine as claimed in claim 2, wherein the bending axis (Z) lies in a plane parallel to both the first translation axis (X) and the second translation axis (Y).

8. The draw-bending machine as claimed in claim 1, wherein the first support arm (10) is movable relative to the base frame (2) about a rotation axis (I) and along a translation direction (U) perpendicular to the rotation axis (I).

9. The draw-bending machine as claimed in claim 8, wherein the translation direction (U) is coincident with the longitudinal extension of the first support arm (10).

10. The draw-bending machine as claimed in claim 8 or 9, wherein the first actuating means (11) of the first support arm (10) is operatively active along the translation direction (U) and the second actuating means (12) of the first support arm (10) is operatively active around the rotation axis (I).

11. The draw-bending machine as claimed in claim 8, wherein the rotation axis (I) is horizontal to the resting surface of the base frame (2).

12. The draw-bending machine as claimed in claim 8, wherein said first (J) and second (K) articulation axes are parallel to the rotation axis (I).

13. The draw-bending machine as claimed in claim 8, wherein the bending axis (Z) lies in a plane perpendicular to the rotation axis (I).

14. The draw-bending machine as claimed in claim 1, further comprising:

an auxiliary arm (21) hinged on the first support arm (10) at a first rotation axis (A);

a fixed base (22) placed close to the base frame (2);

the auxiliary arm (21) being in addition hinged on the fixed base (22) at a second rotation axis (B).

15. The draw-bending machine as claimed in claim 14, wherein the first actuating means (11) is operatively active around the first rotation axis (A) to rotate the first support arm (10) relative to the auxiliary arm (21), and the second actuating means (12) is operatively active around the second rotation axis (B) to rotate the auxiliary arm (21) relative to the fixed base (22).

16. The draw-bending machine as claimed in claim 14, wherein the first rotation axis (A) and second rotation axis (B) are horizontal to the resting surface of the base frame (2) and parallel to each other.

17. The draw-bending machine as claimed in claim 14, wherein the first rotation axis (A), second rotation axis (B), first articulation axis (J) and second articulation axis (K) are parallel to each other.

18. The draw-bending machine as claimed in claim 14, wherein the bending axis (Z) lies in a plane perpendicular to the first rotation axis (A) and the second rotation axis (B).

19. The draw-bending machine as claimed in claim 14, further comprising sliding guides (24) oriented along a translation direction (C) horizontal to the resting surface of the base frame (2) and perpendicular to the first rotation axis (A), second rotation axis (B), first articulation axis (J) and second articulation axis (K).

20. The draw-bending machine as claimed in claim 1, wherein the bending head further comprises:

at least one presser element (5) active on said pipe (6) against the action of said die (4);

at least one locking jaw (7) rotatably movable at the bending axis (Z) together with the die (4), said locking jaw (7) being movable between a first position in which it is spaced apart from the die (4), and a second position in which it is close to the die (4) to tighten the pipe (6) to be bent.

21. The draw-bending machine as claimed in claim 1, wherein the first alignment direction (P) is perpendicular to the bending axis (Z).

22. The draw-bending machine as claimed in claim 1, wherein the second clamp (28) is movable close to or away from the first clamp (279 along said first alignment direction (P).

23. The draw-bending machine as claimed in claim 1, wherein the handling and locking means (51) further comprises:

a first support column (38) mounted on the base frame (2) and provided with an end (38a);

a third support arm (35) having a first end (35a) and a second end (35b) opposite to the first one;

the first gripping unit (25) being fastened to the first end (35a) of the third support arm (35);

the second end (35b) of the third support arm (35) being rotatably linked to the end (38a) of the first column (38) at a third articulation axis (L);

sixth actuating means (39) of the third arm (35) around the third articulation axis (L).

24. The draw-bending machine as claimed in claim 23, wherein the first support column (38) is movable along a first movement direction (V) and along a second movement direction (W) perpendicular to the first movement direction (V).

25. A method of bending pipes comprising the following steps:

positioning a pipe (6) to be bent within an operating space to be reached by a bending head (3) defining a bending axis (Z);

the longitudinal axis of said pipe (6) being disposed along a first alignment direction (P);

the bending axis (Z) lying in a plane perpendicular to the first alignment direction (P);

shifting the bending head (3) a first time to engage the pipe (6) to be bent;

inclining the bending axis (Z) in a first reference direction (Z′

) to bend the pipe (6) in a plane perpendicular to said first reference direction (Z′

);

bending the pipe (6) around the bending axis (Z);

moving the head (3) away from the pipe (6);

axially shifting the pipe (6) along the first alignment direction (P) to change the bending region on said pipe (6);

shifting the bending head (3) at least a second time to engage the pipe (6) to be bent;

inclining the bending axis (Z) at least in a second reference direction (Z″

) distinct from the first one (Z′

) to bend the pipe (6) in a plane perpendicular to said second reference direction (Z′

);

bending the pipe (6) around the bending axis (Z);

wherein the step of positioning the pipe (6) to be bent involves the steps of;

adjusting the mutual distance of a first clamp (27) and of a second clamp (28) of a first gripping unit (25), said first clamp (27) and second clamp (28) being aligned along the first alignment direction (P);

gripping the pipe (6) to be bent with each clamp (27, 28) at two positions disposed a varying axial distance from each other, in order to tighten the pipe (6) at two regions spaced apart from each other;

moving the pipe (6) gripped by the gripping unit (25) within the operating space.