US3886776A

US3886776A - End stop for a forming machine

Info

Publication number: US3886776A
Application number: US445919A
Authority: US
Inventors: David Ian Hudson
Original assignee: Raleigh Industries Ltd
Current assignee: Raleigh Industries Ltd
Priority date: 1973-02-28
Filing date: 1974-02-26
Publication date: 1975-06-03
Anticipated expiration: 1992-06-03
Also published as: GB1466864A

Abstract

A bar stop for a forming machine is pneumatically telescopically extendable towards the end of the bar being fed to the machne. When extended, a cam on the forming rollers of the machine causes a pressure fluid operable piston and cylinder device to index a plate angularly with respect to a ring so that telescopic retraction is restricted under the action of the forward feed of the bar. Further rotation of the forming rollers causes the plate to be indexed into a position allowing relative movement of plate and ring so that telescopic retraction is allowed during the action forming operation which next takes place.

Description

0 United States Patent 1 [111 3,886,776

Hudson June 3, 1975 [54] END STOP FOR A FORMING MACHINE 3,678,719 7/1972 Tsukamoto et al. 72/250 75 l t David Ian Hudson Nottin ham, l 1 men or England g Primary ExaminerLowell A. Larson Attorne A em, or FirmLillin & Siege] [73] Assignee: Raleigh Industries Limited, y g Nottingham, England [57] ABSTRACT [22] Filed: Feb. 26, 1974 A bar stop for a forming machme 1s pneumatically PP 445919 telescopically extendable towards the end of the bar being fed to the machne. When extended, a cam on [30] Foreign Application Priority Data hhe dforminilrollerts of th; mzlrcl'liine cclzauses a preissurev ui opera e PIS on an cy m er evlce to in ex a Feb. 28, 1973 United Kingdom 10152/73 plate angularly with respect to a g so that telescopic retraction is restricted under the action of the forward {2% 8" 72/71 5 11 353 feed of the bar. Further rotation of the forming rollers d 252 428 causes the plate to be indexed into a position allowing 1 le 0 ea relative movement of plate and ring so that telescopic retraction is allowed during the action forming opera- [56] uNlTE g g ztg gs ggfrENTs tion which next takes place.

499,677 6/1893 Daelen 72/252 19 Claims, 5 Drawing Figures 7 32 40 3a 35 37 E /72 g 5 l z a I M x 2 Am r a; 34 21 30 2e 22 24 25 26 25 2'7 SHEET PATENTED JUN 3 1975 END STOP FOR A FORMING MACHINE The present invention relates to a bar stop particularly, but not exclusively, for a forming machine.

In such machines a continuous length of material, for example, steel is fed to a heater and subsequently to a pair of forming rollers where the heated bar is deformed to the required shape. No undue limiting, significance is intended by the use of the term bar as the material may be of any cross-sectional shape. Where a bar being handled is short, which occurs at the end of each long length of bar, there is a tendency for the bar to droop downwards as it is being fed towards the forming rollers. In a known arrangement the material, after passing through the heater, passes through a supporting bush before entering the rollers. A bar stop is disposed at the other side of the arrangement and this stop halts the bar so that the forming operation can be carried out. After forming, the deformed portion of the bar is severed from the remainder of the bar and the bar is advanced again so that a further similar portion can be deformed. As the end of the bar is reached there is an increasing tendency for the bar to droop after passing through the supporting bush and this eventually results in the bar missing the end stop after being pushed through the forming rollers.

According to the present invention, there is provided a bar stop for a forming machine comprising a part movable in relation to the remainder of the stop means enabling that part to be moved in a direction towards the end of a bar to be formed so that the end passes between the forming rollers of the machine and means operative to restrict the movement of the part in a direction opposite to the first mentioned direction under the action of the bar.

For this purpose the bar stop is preferably made telescopic and the movable part is one end section of the telescope.

In one advantageous embodiment, the means for enabling the movable part to be moved comprises a pressure fluid operable piston and cylinder arrangement. In the case of the telescopic arrangement one portion of the telescope constitutes the piston while the other part constitutes the cylinder.

The means operative to restrict the movement of the part in a direction opposite to the first mentioned direction advantageously comprises a ring carrying angularly disposed projection and a tube which is externally formed in a complementary manner to the ring so that in certain relative angular positions of the ring and tube relative axial movement is possible while in other relative angular positions relative axial movement is prevented in the opposite direction.

In another preferred embodiment, in which the bar stop forms part of a forming machine incorporating a pair of forming rollers a cam is disposed on one of the rollers operative to move the ring and tube into a relative position in which relative axial movement is possible. The cam is so positioned that this is carried out before the rollers start the actual forming action itself.

This embodiment also comprises means for indicating a bending malfunction of the forming rollers. Such a malfunction occurs when the bar instead of being rolled by the rollers is pushed to one side. The means for indicating preferably comprises two spring loaded members disposed on opposite sides respectively of the forming nip of the rollers.

In order that the invention may be more clearly understood, one embodiment of the invention will now be described by way of example, with reference to the accompanying drawings, in which:

FIG. 1 shows a diagrammatic arrangement of a wedge rolling machine,

FIG. 2 is a half sectional plan of the end stop for the machine of FIG. 1,

FIG. 3 is a rear end elevational view of the end stop of FIG. 2,

FIG. 4 is a plan view of the end stop shown in FIGS. 2 and 3 and FIG. 5 shows a side elevational view of the lower roller of the machine of FIG. 1.

Referring to FIG. 1 the wedge rolling machine basically comprises a feed unit 1, an induction heating unit 2, a support bush 3, a pair of forming

rollers

4,5 and an end stop 6. The forming rollers are mounted vertically above each other for rotation about horizontal axes and each roller carries a special wedge shaping forming tool 7,8.

Referring now to FIG. 2, the end stop comprises a first sleeve member 21 out of which a second sleeve member 22 is arranged to slide. A rotatable concave nozzle 23 is rotatably mounted in one end of the sleeve member 22 through bearings 24 and 25. A thrust bearing 26 is provided to transmit axial forces to which the nozzle is subjected by the bar and the nozzle is recessed at its free end 27 to receive the bar. A travel limiting arrangement is provided to limit the travel of the sleeve member 22 relative to the body 28 in the direction of the arrow 29. This arrangement comprises a rotatable spider plate 30. This plate 30 consists of a disc which supports four projections disposed at intervals around its circumference and which coacts with a rotationally fixed ring 31 which has an internal formation complementary to the external formation of the peripheral formation of the plate 30. In certain relative angular positions of the ring 31 and plate 30, the ring 31 can move axially freely with respect to the plate 30. If the plate 30 is indexed around 45 from an axial movement position the projections on the periphery of the plate 30 will abut the projections on the interior of the ring 31. To prevent damage to the end stop should this limiting arrangement be accidentally operative during the forming operation when the sleeve member 22 is forced in the direction of the arrow 29 relative to the sleeve member 21 by expansion of the bar during rolling, the sleeve member 21 is connected indirectly to the main body 33 of the machine through a shear pin 32. This pin will shear if the abovementioned condition occurs to allow free movement of the end stop relative to the rest of the machine.

The

sleeve members

21 and 22 are extended out of the body 28 by supplying air to the interior of the body 28. The escape of this air is prevented by seals 34 and the member 22 then acts as a piston and the member 21 as the cylinder of a pneumatic piston and cylinder device (as do the sleeve 21 and the body 28).

A bar bend protection device is disposed adjacent the nozzle 23. This comprises two bend indicator members 35 (only one shown in the half section) disposed on opposite sides respectively of the bar as it is fed to the rollers. Each indicator member 35 is connected to an arrangement of two

members

36 and 37 disposed within a tension spring 38 so as to allow movement of the member 37 relative to the member 36 in any direction member 35 will operate the microswitch 40 to disengage the drive to the forming rollers"4, 5. This will" occur when the bar is bent by the forming tools 7, 8 instead of being deformed by them.

Referring now to FIG. 3, the means for indexing the plate 30 through 45 comprises a pneumatically operable piston and cylinder device 50. The piston rod is connected to a block 51 which is in turn connected through a pin 52 to a pivoting arm 53 which is connected to the plate 30. A microswitch 54 with a microswitch actuating member 55 is provided. This member 55 is actuated by an extension 56 of the block 51 to switch on the feed unit 1 when the ring 31 and plate 30 are in a locked position.

Referring now to FIG. 4, an actuating rod 60 is screwed into a plate 61 which moves in and out with the sleeve member 22. The screw mounting of the rod 60 enables adjustment of the rod 60 with respect to the plate to be made. The rod 60 coacts with an actuating member 62 of a microswitch 63, which is disposed in the clutch circuit of the machine. This switch 63, which is shown in its on position, is activated on the return stroke of the telescope and enables the rollers 4 and to continue rotating. FIG. 4 also shows a lock release switch 64 which is actuated by the lock being released before the deforming step by a cam on the lower roller 5 and is connected in the clutch circuit.

The operation of the machine, which is continuous, will now be described with particular reference to FIG. 5 of the drawing which shows a side elevational view of the lower roller 5 which carries a wedge shaped tool 70 and three

cams

71, 72 and 73. Both the

rollers

4 and 5 rotate continuously.

As the roller 5 rotates with the sleeve member 22 fully retracted at the completion of the forming operation and the switch operated by cam 72 maintaining the clutch circuit, the cam 71 initiates the supply of air to the body 28 to extend sleeve member 22 relative to sleeve member 21 and sleeve member 21 relative to body 28. This extension is limited by the stop bars 43 abutting a bracket supporting the bush 3, and at this point the nozzle 23 has passed between the forming

rollers

4 and 5. The cam 72 operates the cylinder 50 which indirectly rotates the plate 30 to the locked angular position. The cam 71 has terminated its operation cutting off the supply of air to the sleeves. The switch 54, actuated by the block 51 when the lock is engaged. signals the feed unit 1 to operate. The forward fed bar pushes back the inner sleeve 22 until the ring 31 abuts the plate 30. At this point, the switch 63 is actuated, completing part of the clutch circuit, and cutting off the feed unit 1. The cam 72 disengages, releasing the lock by rotating the plate 30 and in turn completing the clutch circuit by switch 64 before the disengagement of cam 73 and before the forming tools strike the bar. This allows the sleeve member 22 to move backwards during the forming part of the cycle. The forming part'of the cycle continues for the angular extent of the tool 70, after which the formed part of the bar is severed from the remaining part of the bar before the next cycle begins.

The cam 73 bypasses the lock release switch 64 and start switch 63 during the non-working part of the cycle but not during the working part of the cycle. During the working part of the cycle these switches must be correctly operated to ensure that the

rollers

4 and 5 continue rotating.

' It will be appreciated that the above described embodiment hasbeen given by way of example only and that many variations are possible without departing from the scope ofthe invention.

What is claimed is;

1. A barstop for a forming machine comprising a part movable in relation to the remainder of the stop, means enabling said part to be moved between the forming tools of said machine and up to the end ofa bar to be formed. means operative to restrict the movement of the part in a direction opposite to the first mentioned direction under the action of the bar, and means operative to release the restriction to accommodate growth in the bar in the opposite direction during a forming operation.

2. A bar stop as claimed in claim 1, which is telescopic and the end section of which constitutes the movable part.

3. A bar stop as claimed in claim 2, wherein the means for enabling the movable parts to be moved comprises a pressure fluid operable piston and cylinder arrangement.

4. A bar stop as claimed in claim 3, in which one portion of the telescope constitutes the piston and the other part constitutes the cylinder.

5. A bar stop as claimed in claim 1, in which a rotatable nozzle is mounted in the movable part.

6. A bar stop as claimed in claim 5, in which the nozzle is recessed to receive a bar.

7. A bar stop as claimed in claim 5, in which a thrust bearing is disposed between the movable part and the nozzle.

8. A bar stop as claimed in claim 1, in which release means are provided to render the means operative to restrict movement inoperative in the event that these means operate incorrectly.

9. A bar stop as claimed in claim 8, in which the release means comprises a shear pin disposed between the body of bar stop and a machine to which it is attached.

10. A bar stop as claimed in claim 1, in which a bar bend protection device is provided.

11. A bar stop as claimed in claim 10, in which the bar bend protection device comprises an indicator member, an actuator disposed for displacement by the indicator member when a bar bend condition is detected, and a microswitch arranged to be operated on displacement of the actuator to avoid further bending of the bar.

12. A bar stop as claimed in claim 11, in which the actuator comprises two members arranged end to end and a tension spring is disposed around said members so as to allow relative movement between the two members in any direction other than axial.

13. A bar stop as claimed in claim 1, in which an actuator is mounted for movement with the movable part and a microswtich, disposed for actuation by the actuator on movement, of the movable part in the opposite direction, is arranged for connection in the supply of circuit of the forming machine.

14. A bar forming machine for forming a length of bar comprising a pair of forming rollers, means for feeding an elongate bar to the forming rollers and a bar stop as claimed in claim 1.

15. A bar forming machine as claimed in claim 14, in which each forming roller carries a wedge shaped forming tool.

16. A bar stop for a forming machine including a part movable in relation to the remainder of the stop, means enabling that part to be moved in a direction towards the end of a bar to be formed and means operative to restrict the movement of the part in a direction opposite to the first mentioned direction under the action of the bar, comprising a ring carrying an angularly disposed projection, a tube which is externally formed in a complementary manner to the ring so that in certain relative angular positions of the ring and tube relative axial movement is possible while in other relative angular position relative axial movement is prevented and indexing means for indexing the tube angularly with respect to the ring.

17. A bar stop as claimed in claim 16, in which the means for indexing comprise a pressure fluid operable piston and cylinder device.

18. A bar stop as claimed in claim 17, in which the piston and cylinder device is operatively connected to a microswitch which, when actuated in the locked position of the ring and tube enables forward feed of bar.

19. A bar stop for a forming machine comprising a part movable in relation to the remainder of the stop, means enabling said part to be moved in a direction towards the end of a bar to be formed so that the end passes between the forming rollers of the machine and means operative to restrict the movement of the part in a direction opposite to the first mentioned direction under the action of the bar comprising a ring carrying an angularly disposed projection and a tube which is externally formed in a complementary manner to the ring so that in certain relative angular positions of the ring and tube relative axial movement is possible while in other relative angular positions relative axial movement is prevented.

Claims

1. A bar stop for a forming machine comprising a part movable in relation to the remainder of the stop, means enabling said part to be moved between the forming tools of said machine and up to the end of a bar to be formed, means operative to restrIct the movement of the part in a direction opposite to the first mentioned direction under the action of the bar, and means operative to release the restriction to accommodate growth in the bar in the opposite direction during a forming operation.