GB2213747A

GB2213747A - Expanding machine for making grilles

Info

Publication number: GB2213747A
Application number: GB8729355A
Authority: GB
Inventors: Fu-Wu Ming
Original assignee: LOPSKING ALUMINUM IND CO Ltd
Current assignee: LOPSKING ALUMINUM IND CO Ltd
Priority date: 1987-12-16
Filing date: 1987-12-16
Publication date: 1989-08-23
Anticipated expiration: 2007-12-16
Also published as: GB8729355D0; GB2213747B

Abstract

The expanding machine includes screw rods 40A and 40B each of which is provided with a left-hand screw thread 42 and a right-hand screw thread 44 and which are rotated by a motor M for producing driving movements in opposite directions. Expanding plates 62 are mounted on the screw rods 40A and 40B to be driven simultaneously by the threads 42 and 44. Workpiece holding bars 70 and 74 and hooks 76 are associated with the expanding plates 62 to hold and expand a slotted workpiece 50 to form a grille. <IMAGE>

Description

TITLE EXPANDING MACHTYE FOR MAKING GRILLES This invention relates to a machine for expanding a slotted workpiece to form a grille or the like.

It is known that grilles used to be installed at windows, doors and the like are fabricated by using an extruded aluminium plate which is shown in Fig. 1 and has alternating parallel thickened and thinned longitudinal portions 52 and 54. The thinned portions are then slotted to form rows of slits 56, the slits in each row being staggered with the slits of the adjacent other rows, as shown in Fig. 2. The slotted plate is then expanded to form a grille.

Various methods have existed in the art for the expansion of the above slotted plate. U.K. Patent No.

1,400,137 discloses a machine for expanding such slotted plates wherein hydraulic actuators are mounted on two sides of a longitudinal frame and slotted workpieces are placed on the frame and the edges of the slotted workpieces are pulled outward by the hydraulic actuators, thereby expanding the workpieces. Such a machine has a disadvantage in that, after a period of service, the quality of the products produced thereby becomes disuniform and the amount of defective products increases. This is due to the pistons of the hydraulic actuators which are liable to wear. Moreover, the hydraulic actuator is expasve and the cost of replacement or maintenance therefor is high.

An object of the invention is to provide a machine for producing grilles and the like which can produce perfect and uniform products for a relatively long service time.

Another object of the invention is to provide a machine for producing grilles which does not employ hydraulic actuators.

Still another object of the invention is to provide a less expensive machine for producing grilles.

The invention provide an expanding machine which includes a frame constituted of a first longitudinal support and a second longitudinal support spaced apart from one another and transverse bearers interconnecting the longitudinal supports; screw rods each having two opposed ends mounted rotatably respectively on the first and second longitudinal supports, and a righthand screw thread and a left-hand screw thread between the opposed ends for producing driving movements in two opposite directions; expanding members mounted on and engaging with the screw rods to be moved by the screw rods towards the first and second longitudinal supports during the expanding operation; workpiece holding means attached to said expanding members and having engaging hooks for engaging with the workpiece; a motor for outputting a rotational movement; and a transmission mechanism in connection with the motor and the screw rods for rotating the screw rods simultaneously.

In one aspect of the invention, the screw rods are arranged in a plurality of pairs each being spaced apart longitudinally from an adjacent pair, and the screw rods of each pair are spaced apart transversely from one another. Two expanding members are mounted on and engage with each pair of the screw rods. The transmission mechanism includes chain wheels and s and chains for connecting the chain wheels to withe thatmotor, Each chain wheel is mounted on one end of one of the screw #rods of each pair. A pair of interengaging gears are respectively ate'ached to each pair of the screw rods at the ends opposite to the chain wheel.One of the screw rods of each pair has the left-hand screw thread near the first longitudinal support and the other one of the screw rods of each pair has the lefthand screw thread near the second longitudinal support.

The workpiece holding means includes a pair of longitudinal spaced apart bars which confine a long narrow passage therebetween for receiving the engaging hooks in a slideable position and which are secured to the expanding plate members.

The exemplary preferred embodiment will be described in detail with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a plate to be slotted; Figure 2 is a plan view of the plate of Fig. 1 which is slotted; Figure 3 is a perspective view of a machine for expanding a slotted plate according to the present invention; Figure 4 is a view showing a workpiece engaging hook member to be associated with longitudinal bars; and Figure 5 shows the workpiece attached to the hooks of Figure 4.

The workpieces used for producing grilles by the present invention are similar to those used conventionally as shown in Figures 1 and 2. Referring to Figure 3, an embodiment of a machine of the present invention includes a frame having a base longitudinal support 12 constituted of longitudinal bearer bars 14 and transverse bearer bars 15. On the bearer bars 15 are mounted support bars 16. Mounting plates 18 are mounted on the support bars 16.

Upright posts 20 and 22 are erected respectively on the support bars 15 and 16. A top longitudinal support 30 is mounted on the upright posts 20 and 22.

In the top support 30 are spaced apart transverse mounting plates 32 and 34. The upper and lower mounting plates 32 and 18 are provided respectively with journal holes 321 and 191, each hole 321 being in alignment with each hole 191. A pair of screw rods 40A and 40B are journalled respectively with their ends in the holes 321 of each mounting plate 32 and holes 191 of each mounting plate 18 through bearing assemblies not shown).

Each screw rod 40A or 40B is provided with a lefthand screw thread 42 and a right-hand screw thread 44 which are spaced apart by an unthreaded portion 43.

Each screw rod 40A has its left-hand thread 42 at its upper portion and right-hand thread 44 at its lower portion. Each screw rod 40B has its right-hand thread 44 at its upper portion and left-hand thread 42 at its lower portion. The form of the threads 42 and 44 may be a square thread or any other desired thread.

Two expanding plates 62 are mounted on each pair of screw rods 40A and 40B. One of the expanding plates 62 has two threaded holes 64 engaging with the upper threads 42 and 44 of the rods 40A and 40B, and the other plate 62 has two thread holes 64 engaging with the lower threads 44 and 42 of the rods 40A and 40B.

The distance between the two expanding plates 62 on each pair of the screw rods is similar to that of other pairs of screw rods. The two plates 62 on each pair of screw rods can be moved in opposite directions towards the upper support 30 and the lower support 12 when the screw rods are rotated.

A pair of upper longitudinal bars 70 and 74 are secured to the plates 62 engaging with the upper threads 42 and 44, and a lower pair of longitudinal bars 70 and 74 are secured to the plate 62 engaging with the lower threads 42 and 44. Each bar 70 and 74 has a cross-section of L-shape and each pair of the bars 70 and 74 confine a long narrow passage therebetween. Hooks 76 are received slideably in the passage between the bars 70 and 74. As better shown in Figure 4, each hook 76 has a hook portion and a mounting portion with rollers 761 which is slideable in the passage and is prevented from being released from the passage by the bars 70 and 74. A chain drive mechanism 80 is mounted on the upper support 30 of the frame and includes transmitting chain wheels 82 each mounted on one of the ends of each screw rod 40A which is journalled in each upper support plate 32. On the other end of each screw rod 40A which is mounted on each lower support plate 8 is mounted a gear 85 which engages with a gear 86 attached to an end of an adjacent screw rod 40B. These chain wheels 82 are interconnected in series by means of endless chains 84 and then connected through a chain 83 and a chain wheel M1 to a reversible motor M which is on the top side of the frame 10 adjacent to the upper support 30. In order to adjust the tension of the chains 8#, chain adjusting rollers 341 are mounted on support plates 34.

The position of the rollers 341 are adjustable by being moved in the slits 342 of the plates 34. By changing the direction of the rotation of the motor, the screw rods 40A and 40B can be rotated clockwise or counterclockwise and the upper and lower bars 70 and 74 can be moved to approach or to move away from one another.

The operation of the machine will be described hereinafter with reference to Fig. 5 in combination with Figure 3. The workpiece 50 is placed between the upper and lower pairs of bars 70 and 74 and the slits 56 of the workpiece 50 adjacent to the opposed edges are caused to engage with the hooks 76. The hooks 76 are slideable in the passage between the bars 70 and 74.

When the motor is switched on, the screw rods 40A are rotated. The rotation of the screw rods 40A is transmitted to the screw rods 40B at the same speed but in an opposite direction. Since the upper threads of the screw rods 40A are left-hand threads 42 and the upper threads of the screw rods 40B are right-hand threads 44, they move the upper expanding plates 62 simultaneously in the same direction towards the upper support 30. Likewise, the lower expanding plates 62 are moved in the same direction towards the lower support 12. thereby expanding the workpiece 50 held by the hooks 76. When one of the expanding plates b2 contacts with a limit switch (not shown) mounted on one of the post 22 near the support 30 or 12, the operation of the motor is stopped. In this situation, the workpiece 50 is expanded to a predetermined dimension.

Since the limit switch is conventional, the detail thereof is not mentioned herein. The expanded workpiece can be removed from the hooks 76 by reversing the direction of the rotation of the motor to cause the bars 70 and 74 to move slightly inward and disengage the hooks 76 from the expanded workpiece.

With the invention thus explained, it is apparent that various modifications and variations can be without departing from the scope of the invention. It is therefore intended that the invention be limited as indicated only in the appended claims.

Claims

CLAIMS:

1. A machine for expanding a workpiece having parallel edge portions, a web portion between the edge portions, and a series of rows of slots in the web portion, the slots of each row being staggered with respect to and overlapping the slots of at least one adjacent row, comprising: a frame having a first longitudinal support and a second longitudinal support spaced apart from one another and transverse bearers interconnecting the longitudinal supports; screw rods each having two opposed ends mounted rotatably respectively on said first and second longitudinal supports, a right-hand screw thread and a left-hand screw thread between first and second longitudinal supports for producing driving movements in two opposite directions; first expanding members mounted on and engaging with said screw rods at a portion of said screw rods near said first support;; second expanding members mounted on and engaging with said screw rods at the other portion of said screw rods near said second support; first workpiece holding means attached to said first expanding members and having engaging hooks for engaging the work-piece; second workpiece holding means attached to said second expanding members and having engaging hooks for engaging the work-piece; a motor for producing a rotational movement; and a transmission mechanism in connection with said motor and said screw rods for rotating said screw rods simultaneously.

2. A machine as claimed in Claim 1, wherein said Screw rods are arranged in a plurality of pairs each being spaced apart longitudinally from an adjacent pair, said screw rods of each pair being spaced apart transversely from one another, each of said first and second expanding members being mounted on and engaging with said each pair of said screw rods.

3. A machine as claimed in Claim 2, wherein said first and second expanding member are plate members each having two threaded holes.

4. A machine as claimed in Claim 1, wherein said first or second workpiece holding means further has a longitudinal bar means secured to said first or second expanding members and confining a sliding passage therein for receiving said engaging hooks.

5. A machine as claimed in Claim 3, wherein said first or second workpiece holding means further has a pair of spaced apart longitudinal bars which confine a long narrow passage therebetween for receiving said engaging hooks in a slideable position and which are secured to said first or second expanding plate members.

6. A machine as claimed in Claim 5, wherein each of said hooks of said first or second workpiece holding means includes a wheeled mounting portion received in said passage and a hook portion extending from said mounting portion.

7. A machine as claimed in Claim 2, wherein said transmission mechanism includes chain wheels and chains for connecting said chain wheels to said motor, each of said chain wheels being mounted on one of said opposed ends of one of said screw rods of each of said pairs.

8. A machine as claimed in Claim 7, wherein said transmission mechanism further includes a pair of interengaging gears respectively attached to said each pair of said screw rods at the ends opposite to said chain wheel.

9. A machine as claimed in Claim 8, wherein one of said screw rods of said each pair has said left-hand screw thread near said first longitudinal support and the other one of said screw rods of said each pair has said left-hand screw thread near said second longitudinal support.

10. A machine as substantially described hereinbefore with reference to the accompanying drawings.

11. Apparatus for expanding a workpiece comprises first and second means for engaging spaced portions of a said workpiece, said first and second means being coupled to a threaded member or respective threaded members whereby rotation of the member or members causes said first and second engaging means to move apart.