Apparatus for feeding workpieces for cross wedge rolling

Workpieces for cross wedge rolling are fed first to an auxiliary trough provided with a sliding gate for removal of workpieces in case of an interruption of the operation of the rolling stand; the workpieces are fed from the auxiliary trough into a stand-by trough to be fed between the rolls of the rolling stand.

BACKGROUND OF THE INVENTION 
The invention relates to cross wedge rolling. The object of the invention 
is the provision of an improved apparatus for feeding workpieces between 
the rolls of a rolling stand. 
By the expression "cross wedge rolling" as used herein there is meant a 
rolling process in which a workpiece is rolled between opposing rolls with 
the axis of the workpiece extending generally parallel to the axes of the 
rolls. 
For this purpose, the application of a stand-by trough has already been 
proposed, such stand-by trough being situated close to the rolls and 
approximately in the rolling axis, into which trough the workpiece is 
supplied by some feeding means and from which it is fed between the rolls 
of the machine. 
This proposal supposes that the workpiece is guided in the machine in the 
course of rolling on its extremities by centering means, one of which is 
also the feeding means. A drawback of this proposed arrangement is that a 
shorter time is available for feeding or a further part of a revolution of 
the rolls is required. In addition, an interruption of feeding into the 
machine is impossible if the workpieces are received continuously, for 
instance from a heating oven. 
SUMMARY OF THE INVENTION 
It is an object of this invention to eliminate this drawback and to provide 
feeding means which enable the capacity of the rolling stand to be used to 
the utmost. According to this invention, a stand-by trough is provided 
substantially in the rolling axis of the machine, with an auxiliary trough 
above the rolling axis, a supply chute above the auxiliary trough for the 
supply of workpieces to the auxiliary trough and terminating in this 
auxiliary trough, with a discharge opening in the auxiliary trough at the 
end of said chute closed by a sliding gate controlled in dependence of the 
operation of the rolling stand, and power cylinders for shifting the 
workpieces in the auxiliary trough and in the stand-by trough.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 and 2, guiding segments 2 and rolling tools 3 are 
fixed on opposed parallel rolls 1 of the machine. The cylindrical 
workpiece 4 is inserted by shifting it in direction of the axis x of 
rolling between the rotating rolls 1 so that it is guided, in the course 
of its being inserted, by the segments 2, which are beveled and preferably 
also by guide jibs, indicated by broken lines. After complete insertion 
the workpiece is in the position shown in FIG. 1, wherein it is in contact 
with rolling tools 3. 
A stand-by trough 5 is provided in close proximity to the rolls 1, trough 5 
supporting a workpiece 4 on the rolling axis x. A pneumatic cylinder 6 
with a piston rod 6a is arranged behind the trough 5 on the same x axis. 
An auxiliary trough 7 of V cross section for further workpieces 4" is 
provided above the x axis, a feeding chute 7a forming one of its walls. 
Such feeding chute 7a is attached to a diagrammatically indicated heating 
device 10 for the workpieces. 
The first wall 7a of the auxiliary trough 7 has a discharge opening 7b, 
which is closed by a sliding gate 8. Gate 8 is slidable upwards in the 
feeding chute 7a as indicated by the arrow in FIG. 3. The opening 7b is 
located at or at least near the junction of the two walls 7a and 7c of the 
auxiliary trough. 
The second wall 7c of the trough 7 extends downwards and serves as a chute 
terminating into a box 11 (see FIG. 2) from which it may be returned to 
the heating device 10 when the mill stand is again in operation. 
A pneumatic cylinder 9 with a piston rod 9a is situated behind the 
auxiliary trough 7 in alignment with the lowermost workpiece 4" in the 
trough 7. 
Each of the pneumatic cylinders 6 and 9 is controlled by a respective 
switch which is actuated by a two-step cam on one of the rolls. In FIG. 1 
one such cam 13 is shown, such switch actuating a switch 12. 
The above-described apparatus operates as follows: 
The rolling mill stand controls the operation of the feeding device as by 
switches operated in synchronism with the rolls 1, said switches 
controlling solenoid operated valves for pressure fluid fed to the 
cylinders 6 and 9. At the time when the forward ends of guiding segments 2 
are close to the rolling axis x, an impulse is released for the pneumatic 
cylinder 6 to shift a workpiece 4' from the stand-by trough 5 by the 
piston rod 6a to a position between the guiding segments 2. When the 
piston rod 6a of the pneumatic cylinder 6 returns to the right of its 
original position, the apparatus releases an impulse for operation of the 
pneumatic cylinder 9, which by means of its piston rod 9a shifts the 
workpiece 4" from the auxiliary trough 7 toward the mill stand; the 
lowermost workpiece 4" then falls into the stand-by trough 5 to be 
prepared for rolling. This process proceeds at a time when a first 
workpiece 4 is being rolled. 
As soon as the piston rod 9a returns to the right to its starting position, 
a new workpiece 4" falls into the auxiliary trough 7 by way of the feeding 
chute 7a, such workpiece 4" having been expelled from the heating device 
10 at a prior predetermined moment. 
If the rolling mill comes to a standstill and the heating device 10 must 
operate continuously, after a certain time of rest the apparatus generates 
a signal for shifting the sliding gate 8 upwards in the direction of the 
arrow (FIG. 3); the sliding gate 8 opens the discharge opening 7b by way 
of which the workpiece 4" leaves the trough 7 and falls into the box 11 by 
way of the discharge chute 7c. 
The sliding gate 8 remains in its raised, open position until the rolling 
mill again starts its operation. The sliding gate 8 is controlled by any 
known mechanical or other device suitable for this purpose in dependence 
on the operation of the rolling stand. 
Although the invention is illustrated and described with reference to one 
preferred embodiment thereof, it is to be expressly understood that it is 
in no way limited to the disclosure of such a preferred embodiment, but is 
capable of numerous modifications with the scope of the appended claims.