AU646554B2

AU646554B2 - Nail rolling apparatus

Info

Publication number: AU646554B2
Application number: AU15057/92A
Authority: AU
Inventors: Ronald Moore
Original assignee: Brambles Australia Ltd
Current assignee: Cleanaway Pty Ltd
Priority date: 1991-04-24
Filing date: 1992-04-23
Publication date: 1994-02-24
Anticipated expiration: 2012-04-23
Also published as: AU1505792A

Description

S F Ref: 209210

AUSTRALIA

PATENTS ACT 1990 646554 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant: Op...

Brambles Australia Limited Level 40, Gateway 1 Macquarie Place Sydney New South Males 2000

AUSTRALIA

Ronald Moore Actual Inventor(s): Address for Service: Invention Title: 0 Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Nail Rolling Apparatus ASSOCIATED PROVISIONAL [311 Application No(s) PK5795 APPLICATION DETAILS [33] Country

AU

[32] Application Date 24 April 1991 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5815/4 -2- BACKGROUND OF THE INVENTION This invention relates to an apparatus for rolling flat nails, or other sharp objects, which stick out of an article, such as a pallet.

Nooden pallets generally comprise at least two, usually three, horizontal bearers having fixed to an edge thereof a number of cross boards, the end ones of which are designated lead boards. In many cases, the lead board is not square with the end edge of the bearers. This may be due either to manufacturing errors or due to accidental movement after use. However, in order to reuse the pallets, it is desirable that the lead board be adjusted so that it is square with the end edge of the bearers. The boards are therefore moved and the pallet repaired for re-use. When repairing the pallets, however, ends of nails are very often left sticking out of the boards. Such ends are dangerous and undesirable as they can puncture or otherwise damage goods placed on the pallets. Indeed, it has been known for nails to be sticking out from brand new pallets.

BRIEF SUMMARY OF THE INVENTION Accordingly, the invention provides an apparatus for rolling flat nails, or other sharp objects, which stick out of an article, the 20 apparatus comprising a frame, at least one rotatable upper roller having a rolling surface and an axle, mounting means for mounting the axle on the frame, drive means for rotating the upper roller, biasing means for biasing thq upper roller against a surface of an article moving on a conveyor such that the rolling surface engages and flattens any sharp object extending from the surface of the article.

Preferably, there is provided a convwyor for moving the article through the apparatus. However, the frame could, alternatively, be arranged to be positioned adjacent an existing conveyor. Preferably also, the apparatus is provided with one or more outfeed support 30 rollers. The outfeed support roller(s) Is(are) preferably not driven.

In a preferred embodiment, the upper roller is mounted on the frame so as to be above the conveyor. The upper roller is preferably free to 'move in a substantially vertical direction so as to allow the upper roller to rotate and move upwards over the article as th. !cle moves on the conveyor. The roller mounting means preferably comprises a pair of sliding means, one at each side of the upper roller, each comprising a bearing in which the roller axle is mounted, a slide block carrying the bearing and slide frame plates within which the slide block is slidably mounted.

csh/0376E -3- The biasing means preferably comprises a pressure producing means for exerting pressure on the upper roller to bias the upper roller against the article on the conveyor.

In a preferred embodiment, three upper roller assemblies are provided, each comprising an upper roller having a rolling surface and an axle, mounting means for mounting the axle on the frame Pnd biasing means for biasing the upper roller against a surface of an article moving on a conveyor. Preferably, the three upper rollers are aligned with horizontal bearers forming a pallet from which nails may be sticking out.

The apparatus preferably further comprises sensing means for sensing the presence of an article on the conveyor and for controlling the pressure producing means to produce pressure on the roller for a predetermined period of time while the article is below the roller. The pressure producing means preferably comprises a variable volume gas chamber and a p.ston within the chamber and coupled to the slide block of the roller mounting means to bias the slide block downwards against the surface of the article on the conveyor.

Preferably, the apparatus further comprises a lower roller associated with each upper roller and positioned In opposing relation 20 thereto so that the article passes between respective upper and lower rollers and is supported on the lower roller(s). The lower roller(s) preferably has(have) half the diameter of the upper roller(s) and is(are) driven to rotate at twice the speed of the upper roller(s).

BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of an apparatus for rolling flat nails, or other sharp objects, sticking out of an article, such as a pallet, will now be more fully described, by way of example, with reference to the drawings, of which: Figure 1 Is a front elevation of an apparatus according to one embodiment of the invention; and Figure 2 is a side schematic view of the apparatus of Figure 1.

DETAILED DESCRIPTION OF THE DRAWINGS Thus, there is shown in the drawings, an apparatus 1 according to one embodiment of the Invention for flattening sharp objects, such as nails, sticking upwardly out of articles such as wooden pallets, which are roving along a conveyor, for example during a repair operation of the pallets. The apparatus 1 basically comprises a frame 2 having an input conveyor 30 and a set of three upper iollers 4, 5 and 6 arranged in r r

Y

csh/0376E -4parallel to engage the top of a pallet 31 along the side edges and centre line thereof as the pallet 31 moves on the conveyor 30 through the apparatus 1. In opposing corresponding relationship to each of the upper rollers 4, 5 and 6, there is also provided a lower roller 7, 8 and 9 arranged to provide c support for the pallet 31 on the conveyor 30 when the upper rollers 4, 5 and 6 exert pressure on the top face of the pallet 31. The lower rollers 7, 8 and 9 are preferably half the diameter of upper rollers 4, 5 and 6 and are therefore driven to rotate at twice the speed of the upper rollers 4, 5 and 6. The conveyor 30 is driven by a duplex chain 32 running at the same rolling diameter as the lower rollers 7, 8 and 9. This maximises the load bearing surface and improves the traction of the pallet.

A motor 3 with variable ratio transmission is provided to drive the rollers via a torque limiter 33. The motor 3 drives a common shaft 11 by means of a duplex chain 34 driving an independent drive sprocket 35 on the common shaft 11. The common shaft 11 is mounted on three bearing blocks in the frame 2. The drive sprocket 35 is arranged on the internal side of frame 2. Also on the internal side of frame 2 mounted on common shaft 11 are tnree upper roller drive sprockets, of which only one 13 is shown, to drivep, via three respective simplex chain drives 12, the respective upper rollers 6. As shown at arrows 10, the chain drives 12 o*e. are adjusted to provide a certain amount of slack in order to allow the upper rollers 6 to move in the vertical direction. Also mounted on common shaft 11, but on the external side of frame 2, is a lower roller drive sprocket 14 arranged for driving the lower rollers 7, 8 and 9.

Lower rollers 7, 8 and 9 are mounted on a common axle 15 having on one end thereof, external to frame 2, a drive sprocket 28 which is coupled, via chain 16, passing over a chain tensioner 36, to a duplex chain sprocket 17. Duplex chain sprocket 17 i's driven by simplex chain 30 18, which passes around lower roller drive sprocket 14 on common shaft .0.0 11, a first simplex chain sprocket 19, duplex chain sprocket 17 and a second simplex chain sprocket 20, before returning to lower roller drive sprocket 14. Thus, duplex chain sprocket 17 is arranged to rotate in the opposite direction to first and second simplex chain sprockets 19 and so as to drive the lower rollers 7, 8 and 9 in the opposite direction to upper rollers 4, 5 and 6.

Thus, as the pallet 31 on the conveyor 30 passes through apparatus 1 in the direction shown by arrow 21, the upper and lower rollers are csh/0376E rotating so as to engage the pallet 31 at the same speed as the conveyor Is moving the pallet 31 through the apparatus. As described above, the conveyor 30 is being driven via chain 32 from a sprocket on shaft having the same diameter as the lower rollers. To make sure the speed is correct, the motor 3 can be adjusted due to the variable ratio transmission and the relative speeds of the upper and lower rollers can be adjusted by moving first and second simplex chain sprockets 19 and which are aujustable uy eccentric cams.

As the pallet moves through the apparatus, it will be apparent that the upper rollers 4, 5 and 6 must be free to move up over the pallet as it's front edge reaches the rollers. Thus, each of the upper rollers 4, and 6 is mounted in a bearing 22 which is carried by a slide block 23.

The slide block 23 is arranged to be able to slide vertically within nylon guides 37 in slide retaining blocks 24 and 25 mounted in frame 2.

The slide block 23 is adjustable by threaded bolts 26 which can be screwed in or out so as to adjust the basic height of the upper rollers depending on the height of the pallets entering the apparatus.

Thus, it will be clear that, as a pallet reaches upper rollers 4, and 6, they are allowed to move upwards as their corresponding bearing slides upwards in slide block 23 so that the roller rolls up and over the top of the pallet. However, in order to flatten any nails or other sharp objects sticking out of the top of the pallet, it is necessary to bias the rollers downwards against the top surface of the pallet once they are rolling along the top surface. There is therefore provided a biasing means comprising an oil hydraulic pressure cylinder 27 mounted on frame 2 above each of the slide blocks 23. The oil in the cylinder is coupled by a hose 38 to an air over oil accumulator 39. When the air above the oil in the accumulator 39 is pressurized by an air regulator 40 having a quick release air solenoid valve, piston 29 within the cylinder 27 is 30 biased against the corresponding slide block 23, so as to exert downward pressure by the upper rollers against the top surface of the pallet. IP order for the air regulator 40 to only exert pressure for the appropriate time, a proximity detector 41, such as a photo sensor, is arranged to sense the presence of the Front edge of a pallet via a port hole 42 in frame 2. The proximity detector 41 switches a timer 43 which controls the air regulator 40 so that the air is pressurized for a predetermined time period determined according to the length of the pallrt and the speed of movement of the pallet through the apparatus. When no pallets csh/0376E -6are in the apparatus, the proximity detector is in the normally open contact stage and there is no air pressure in the accumulator. When a pallet enters the apparatus, the top rollers are free to climb up over the pallet lead board. At this instant the proximity detector switches to apply air pressure to the accumunlator and hence downward pressure on each of the upper rollers. The rollers then roll any protruding nails into the pallet and the timer is preset to release the pressure as soon the end of the pallet is reached so that the roclers are not under )ad when they move down the end of the pallet. It will be appreciated that a separate slide block and oil cylinder is provided for each upper roller. i It will be apparent that as slide blocks 23 move up and down within the slide retaining blocks 24 and 25, the length of the chains driving each roller from the upper roller drive sprockets 13 on common shaft 11, must vary. This change of length is not great and, as described above, is compensated by providing sufficient slack 10 in the drive chains.

S* Both the upper and lower rollers are preferably solid and made of mild steel having a case-hardened knurled wear shoe 45, which has been heat treated, press-fitted and lightly welded onto the rollers.

Alternatively, the shoe could be shrunk onto the outside of each roller drum.

It will therefore be apparent, that, in the apparatus described above, as a pallet having nails sticking up from its top surface passes through the apparatus, the upper roller will first move up and onto the top surface of the pallet, following which the proximity switch will pressurize the pressure cylinder for a predetermined time so that the upper roller is biased downwards against the top surface of the pallet, which is supported by the lower rollers, so that the nails sticking above the top surface of the pallet are rolled into the pallet by the knurled J* 30 surface of the upper rollers.

To improve pallet stability during rolling on the outfeed from the apparatus, three undriven outfeed rollers 44 are provided immediately after each of the bottom rollers. These outfeed rollers are mounted in needle bearings due to the high loads imposed while the upper rollers are still under pressure.

The apparatus is therefore useful in a pallet repair line between the actual repairing stage and the stage of stacking the repaired pallets. It will also be apparent that, although the apparatus has been csh/0376E 7 described with three parallel sets of rollers, if the pallets to be repaired have a different number of lines along which nails may be sticking up, a suitable number of rollers may, of course, be provided.

Furthermore, it will be clear that any suitable biasing means can be used and that the drive means for the rollers can also be of any suitable type.

o r C C C. C r r cc o csh/0376E

Claims

1. An apparatus for rolling flat nails, or other sharp objects, which stick out of an article, such as a pallet, the apparatus comprising a frame, at least one rotatable upper roller having a rolling surface and an axle, mounting means for mounting the axle on the frame, drive means for rotating the upper rol:er, biasing means for biasing the upper roller against a surface of an article moving on a conveyor such that the rolling surface engages and flattens -any sharp object extending from the surface of the article.

2. An apparatus according to claim 1, wherein three upper roller assemblies are provided, each comprising an upper roller having a rolling surface and an axle, mounting means for mounting the axle on the frame and biasing means for biasing the upper roller against a surface of an article moving on a conveyor.

3. An apparatus according to claim 2, wherein the article is a pallet having three horizontal bearers with which the three upper rollers are aligned.

An apparatus according to any preceding claim, including a conveyor for moving the article through the apparatus. 20

5. An apparatus according to any one of claims 1 to 3, wherein the frame is arranged to be positioned adjacent an existing conveyor.

6, An apparatus according to any preceding claim, further comprising one or more outfeed support rollers.

7. An apparatus according to claim 6, wherein the outfeed support roller(s) is(are) not driven.

8. An apparatus according to any preceding claim, wheretn the or each upper roller is mounted on the frame so as to be above the conveyor.

9. An apparatus according to any preceding claim, wherein the or each upper roller is free to move In a substantially vertical direction 30 so as to allow the upper roller to rotate and move upwards over the article as the article moves on the conveyor.

An apparatus according to any preceding claim, wherein the or each mounting means comprises a pair of sliding means, one at each side of the respective upper roller, each comprising a bearing in which the roller axle is mounted, a slide block carrying the bearing and slide frame plates within which the slide block is slidably mounted.

11. An apparatus according to any preceding claim, further comprising sensing means for sensing the presence of an article on the conveyor. csh/0376E -9-

12. An apparatus according to any one of claims 1 to 10, wherein the or each biasing means comprises a pressure producing means for exerting pressure on the upper roller to bias the upper roller against the article on the conveyor.

13. An apparatus according to claim 12, further comprising sensing means for sensing the presence of an article on the conveyor and for controlling the pressure producing means to produce pressure on the roller for a predetermined period of time while the article is below the roller.

14. An apparatus according to either claim 12 or claim 13, wherein the pressure producing means comprises a variable volume oil chamber and a piston within the chamber and coupled to the slide block of the roller mounting means to bias the slide block downwards against the surface of the article on the conveyor.

15. An apparatus according to any preceding claim, further comprising a lower roller associated with the or each upper roller and 9positioned in opposing relation thereto so that the article passes between respective upper and lower rollers and Is supported on the lower roller(s). 20

16. An apparatus according to claim 15, wherein the or each lower roller has half the diameter of the respective upper roller and is driven to rotate at twice the speed of the upper roller. S17. An apparatus for rolling flat nails, or other sharp objects, which stick out of an article, such as a pallet, substantially as hereinbefore described with reference to the drawings. DATED this TWENTY THIRD day of APRIL 1992 Brambles Australia Limited Patent Attorneys for the Applicant SPRUSON FERGUSON csh/0376E ABSTRACT Nail Rolling Apparatus An apparatus for rolling flat nails, or other sharp objects, which stick out of an article, such as a pallet the apparatus (1) comprising a frame three upper roller assemblies, each comprising an upper roller having a rolling surface and an axle, mounting means (22) for mounting the axle on the frame and biasing means (27,29) for biasing the upper roller against a surface of the pallet moving on a conveyor (30) such that the rolling surface engages and flattens any sharp object extending from the surface of the pallet. Lower rollers are also provided below each of the upper rollers to support the pallet against the pressure of the upper rollers. The apparatus also includes a motor for driving the rollers and timing means for switching the biasing means on for only the time during which the pallet is below the upper rollers. Figure 2 &e O* V V csh/0376E