CS205015B2 - Bending machine for the bar material particularly reinforcement rods in the concrete - Google Patents

Abstract

1470290 Bending EVG ENTWICKLUNGSU VERWALTUNGS-GmbH 26 Nov 1975 [16 Dec 1974] 48652/75 Heading B3E A bar bending machine controlled by a programme control device comprises a stationary mandrel 1, a bending tool 3 swingable about the mandrel, and a clamping device 25 upstream of the mandrel along a bar feed path, to prevent the bar from twisting about its axis during bending, e.g. in the case of bar having helically arranged ribs. In the figure, bending is effected by a jack 4, and a movable clamp element 11 is forced against a fixed clamp element 10 by jack 13, the piston of the latter having a larger cross-section than that of jack 4. The fixed clamp element 10 may serve also as the fixed element of a bar shear device. The two jacks may be controlled by a single electrohydraulic valve 20 as shown, or by separate valves. On completion of the bending step, the bar may be advanced for shearing to length or for a further bend. An alternative bending mandrel may be disposed on the other side of the bar feed path, the tool 3 being disposable and actuable to bend the bar about the alternative mandrel in the opposite direction to that shown. The tool 3 may have an arcuate or V-section groove. Engagement of a stop 80 adjustably mounted on the rod 98 with the ring 88 stops movement of the tube towards the cutter and engagement of a stop 82 adjustably mounted on the rod 98 with a ring 90 controls retraction of the support 64 on which the grippers are mounted and which is secured to the support 86 of stop 82. The distance between stop 82 and ring 90 determines the length of tube to be fed over the cutter 54. In use, while the tube is fed towards the cutter, the cutter unit is fed towards the tube as far as stop (121), Fig. 1 (not shown), will allow, by an hydraulic cylinder (118). A clamp 100 is drawn down by an hydraulic cylinder 106 to clamp the tube against member 102 during shearing. The clamp members are spaced from jaws 58, 60 by 90 degrees and the gripper 60 is disengaged from the tube before the clamp 100 is applied to the tube. The cylinder 30 is actuated to pivot the arm 22 downwardly so that the cutter 54 indents the tube, Fig. 7. The shaft 36 is then rotated through a onerevolution clutch to cause the cutter 54 to roll round the whole inner periphery of the tube to shear off an end portion against an annular cutter. An electrohydraulic system for automatic operation of the device includes a limit switch which has to be contacted by a falling sheared-off end portion before another shear cycle is initiated.

Description

The invention relates to a bending machine for a bar material, in particular concrete reinforcing bars, with at least one fixed bending mandrel and a bending tool pivotable around the bending mandrel.

On such machines, concrete reinforcement bars in large series are bent in the construction industry. The production process is therefore automated and controlled by the software.

The bending machine is provided with a motor-driven feed device which unwinds the rod material from the supply spool. The adjustable measuring device measures the preset length of the material and stops the feed device. As it advances, the feed material passes through a set of straightening rollers whose axes of rotation are arranged in different planes that straighten the extended bar material. When the feeding is complete, the bending device is activated automatically to bend the bar material to a preselected angle. After the bending is completed, the software actuates a shearing device arranged near a rigid bending mandrel to cut the bent material to a set length.

After cutting off the finished reinforcing bar, the program device commands the next programmed cycle. Such a bar bending machine is known from Austrian Patent 314 314.

These bending machines work reliably and accurately when bending a bar material with a smooth surface. At present, however, mainly reinforced bars with ribbed surfaces are used in the construction industry for their reliable connection with the concrete mixture. The ribs are exceptionally designed as longitudinal, mostly curled into a helix. This means that the major axes of inertia of the cross-section of the ribbed bar also twist in the direction of the longitudinal axis of the bar into a helix. Under these circumstances, only exceptionally some of the major axes of inertia of the bent bar material lie in the plane of the bend. When bending the rod material along an axis that is not parallel to one of the major axes of inertia of the bending profile, additional twisting moons are formed so that the rod material deflects sideways when bending. If several bends are carried out in succession, then a reinforcing bar lying in the plane is not formed, but a bar which is spatially distorted, which is unusable.

SUMMARY OF THE INVENTION The object of the present invention is to provide a bending machine for bar material which ensures that the bar material bends exactly in a specified plane regardless of the position of the principal axes of inertia of the bent cross-section.

The problem is solved by creating a bending machine

203015 machines for - rod material, - in particular reinforcing bars for concrete, - with at least one. a rigid bending mandrel and a bending tool, a pivotable bending mandrel, as well as a bar material clamping device, which differs from the known solutions according to the invention in that the bar material clamping device is provided in the direction of the forward feed of the bar material immediately before the fixed bending mandrel.

In order to ensure a secure clamping of the bar material and thereby to increase the certainty that the bar material will bend in a preset plane, the clamping device according to the invention is provided with a movable clamping jaw coupled to the clamping work roller. and it is essential that the cross-section of the clamping work roll is larger than the cross-section of the bending work roll.

A particularly simple solution of the bending machine according to the invention arises when the bending working cylinder and the clamping working cylinder are connected in parallel to a common supply line and a common return line in which a common control valve is arranged.

A further significant simplification of the bending machine is achieved in accordance with the invention in that the clamping device is provided with a fixed clamping jaw which is at the same time a fixed jaw of the bar material cutting device.

Safe - guiding the bent bar material - the bending tool according to the invention is designed as a pulley with a circumferential groove with a circular arc or U-shaped hatch.

The advantage of the bar material bending machine according to the invention is that even complex composite bars with many bends, made of bar material with coiled ribs, bend precisely in a specified plane.

Examples of bar bending machines according to the invention are shown in the accompanying drawings, in which Fig. 1 shows a bending machine with two control valves, Fig. 2 shows a detail of the bending tool and Fig. 3 bending - - machine with - one-common control valve. ;

The bar-bending machine is provided with a rigid bending mandrel 1 on which a pivot arm 2 is mounted, at whose free end a pivotable pulley-shaped bending tool 3 with a circumferential groove is arranged. The pivot arm 2 is reversibly rotated by a bending work roll 4, which is pivotally connected to the bending stand by one end thereof. wherein the piston rod 5 of the bending working cylinder 4 is articulated to the pivot arm 2 by means of a pin 6.

Just -Before - -ohýbacím fixed mandrel 1 is (a clamping device 25 for. - "clamping bars of the material. The clamping device 25 clamps the rail to a stationary not only in the axial direction, but it also ensures secure against twisting. Inac _{up of 25 device;} is provided with a rigid frame 7, - in which is provided the input is selected _as 8 and the output of _Y taken 9 for the rod _S is _M are VN _and fine _of axial. ga _p r recess _{- 8} - _p ro easier _for ga _pt YCE _S a funnel extended _a reputation. the clamping frame -7 - device 25- is - whether or not provided with _{p-resisting pi} NAC _and the jaws 10 and _{IP yb} Sporadic oh u _p NAc -čelist И _{d p} ro _yc t _S.

The movable clamping jaw 11 by means of piston rod 12 is connected to the piston of the clamping cylinder 13. The cross section pracovního- clamping piston working in _{al 3} CE 1 _E t in _width than the diameter _UR ez finger flexor _¹H the working cylinder _{4, No.} IMZ is ensured that clamping force exceeds in size the bending strength, so that the rod is clamped completely _b ez _p e n _{No. of} motionless.

The clamping cylinder 13 is working -Use clamping _{larger-return} · I will break _{14 running in} the supply pipe and upfoacího - 15 through the clamping control valve 16 - is connected with -na FIG. Pressure medium source, not shown. Similarly ohýbací- working cylinder 4 by means of a bending line 17 -vratného - and -ohýbacího supply line - 18 _BC EC ýbac _{h i} r _{d diC} Ventilla 19 associated with FIG. Nym source, not shown, _{of the} button b _s's medium.

The bending machine according to the invention operates as follows: FIG. feed device not shown, inserted through a _T-S YC input vybrárnm 8 between the fixed clamping jaw 10 and the movable clamping čehstí 1 _{d 1} and then output the recess 9 around a solid mandrel 1 to the preset length. Then, the programming device commands the clamping control valve 16 which adjusts SE- such that the clamping work roll 1 by using _{I 3 -} the rod is pressed 1-2 _{'p y} oh blivou clamping jaw 11 towards the fixed clamping jaw 10 and the rod firmly clamped S. Immediately -na command it receives bending control valve 19, which actuates the folding work roll 4 _kt era _yk ývne above _alkyl VNY -o _H ýbac 3 _and a tool _whose m _{F -} rod _{- S} o _h a non _- preset angle . After completion of - bending of the work roll bending four - clamping and working cylinder 13 returns to Buf _H oz _Ch positions.

In another - embodiment shown in -o _b r. _{3 -} is the mechanical part of the machine _H ýbacího identical - with the example previously mentioned, the only difference is in the control device. 0hýbací staff from clamping cylinder 4 and the - working cylinder 13 in this case are connected to the _p o _l ečný driver _and valve ₂ using _I 0 common _{e h} op _{of manufacture} water pipe 21 and _p ole _No. Joint return pipe 22nd

Bending machine according to the invention can also pro- -ohýbání in both directions and is provided -dvěma fixed folding mandrels - a _{straight alkyl} industrial grade esuvným above the bending tool.

Claims (5)

SUBJECT Bar bending machine, in particular concrete reinforcing bars, with at least one fixed bending mandrel and bending tool, pivotable around a bending mandrel and a bar material clamping device, characterized in that the bar material clamping device (25) is in the forward direction a feed of the bar material is provided immediately before the fixed bending mandrel (1). Bending machine according to claim 1, characterized in that the clamping device (25) is provided with a movable clamping jaw (11) and a clamping working cylinder (13), the bending tool (3) being connected to the bending working cylinder (4), wherein the cross-section of the clamping work roll (13) is larger than the cross-section of the bending work roll (4). invention Bending machine according to claim 2, characterized in that the bending work roll (4) and the clamping work roll (13) are connected in parallel to a common pressure supply line (21) and a common return line (22) which are connected to a common control valve (20). Bending machine according to Claims 1 to 3, characterized in that the clamping device (25) is provided with a fixed clamping jaw (10). 5. Bending machine. according to Claims 1 to 4, characterized in that the bending tool (3) is pivotable around a fixed bending mandrel (1) and is in the form of a roller having a circumferential groove having a circular arc or U-section.