MX2007004707A

MX2007004707A - Apparatus for projecting wire.

Info

Publication number: MX2007004707A
Application number: MX2007004707A
Authority: MX
Inventors: Peter Craig Claridge
Original assignee: South Fence Machinery Ltd
Priority date: 2004-10-20
Filing date: 2005-10-20
Publication date: 2007-10-05
Also published as: EP1802408A1; EP1802408B1; EP1802408A4; US20090272458A1; WO2006043842A1

Abstract

<u>ABSTRACT</u> An apparatus (100) for projecting a stay wire (7) across a plurality of line wires (2) in a fence mesh forming machine. The apparatus (100) has at least two rollers (109) defining a wire travel path (W) between the rollers and arranged to contact the wire (7) and move the wire along the wire travel path (W) upon rotation of the rollers (109). At least one of the rollers (109) is arranged to be directly driven by a respective motor (115). Preferably, each of the rollers (109) is arranged to be directly driven by a respective motor (115).

Description

APPLIANCE TO PROJECT CABLE FIELD OF THE INVENTION This invention relates to an apparatus for protecting a support cable through a plurality of cable lines in a fence mesh forming machine.

BACKGROUND OF THE INVENTION Fence mesh shapes are known in which the cables forming the fence are tied together with each other or have many cable intersections. In general, the fence net attached is stronger than the cable fence in which fence cables are tied together at their intersections and which is typically used in light domestic or industrial applications. The fence net attached is used for applications where additional resistance is required, such as to enclose larger or stronger animals such as horses or deer for example. The fence net attached with a rectangular or square mesh for example is typically formed of several parallel in-line cables, which will generally extend horizontally when the fence net is placed in position between fence posts, and the lengths of the support cable which extends laterally through the wires in line to regular spacings (and usually vertically when the fence net is placed in position.) In machines for forming fence netting tied several cables in line are fed to a bed of the machine comprising a number of similar bound boxes, and the support wire is It feeds into the bed of the machine through the in-line cables, such machines typically have a similar step operation and form a series of knots along a length of the support cable at each intersection of the support cable and the cables. On-line at each operational step or "stroke" of the machine In each step or stroke the cables in line are advanced forward in parallel through the boxes tied side by side of the bed of the machine, the support cable is fed inside the bed of the machine through the cables in line in the bound boxes, at approximately 90 degrees towards the cables in line in the case of a machine for forming a rectangular fence, a length of support cable is cut, and simultaneously in each box tied at an intersection between the cables in line and the support cable a knot is formed securing the support cable to the cable in line. A fence mesh forming machine is described in U.S. Patent No. 6,668,869. This fence mesh machine is generally shown in Figures 1 a and 1 b. Figure 1a shows several cables in continuous line 2 and bundling cables 3 being fed to a bed 4 of machine 1, whose bed has a plurality of boxes tied side by side 5. The wires in line 2 enter the machine at its base, are rotated through 90 degrees around the rollers 6 and pass vertically through the tied boxes 5. A cable in line 2 and a bundle cable 3 pass through each box attached 5 with different orientations. A continuous support cable 7 is projected through the bed of the machine via a support cable feeding apparatus comprising two aligned pairs of driven rollers 8 and a free running guide pulley 8a to transversely cross each of the bound boxes 5, thus forming a plurality of wire cable line cable intersections. The machine 1 has a main drive roller 9 which pulls the fence mesh completed through the bound boxes 5, the drive roller being driven by an electric motor 10. The fence net completed (indicated generally by reference number 11 in Figure 1) then it extends around an additional roll 12, and could typically be extended to a winding machine or winding unit (not shown) to form it within a roll for ease of handling and transport. The close-knit mesh forming machine 1 generally has a similar step operation and forms a series of bundles along the length of the support cable 7 at each cable intersection of the support cable at each step or "stroke" of the machine. At each step or hit the cables in line 2 advanced forward in parallel through the boxes tied side by side 5 in the bed of the machine 4 via the drive roller 9, a support cable 7 is fed into the bed 4 of the machine through the wires in line in the tied boxes 5, at 90 ° to form the square fence mesh as shown, a length of the support wire 7 is cut, and simultaneously in each box attached 5 at each intersection between the wires in line and the support wire a knot is formed securing the support wire towards the cable in line. Fig. 1c shows the drive mechanism of the support cable feeding apparatus of the system of Fig. 1 a and 1 b. Each roller 8, 8 'is mounted on a respective elongated shaft 8a, 8a', each of which bears a gear 8b, 8b '. The upper gears 8b engage with the lower gears 8b ', and the lower gears 8b', engage with a drive gear 8c on a drive shaft 8d. The rollers are driven by a relatively large individual drive motor (not shown), and drive force is transferred from the motor via the drive shaft 8d and the gear 8c, to the lower gears 8b '. The driving force is transmitted from the lower gears 8b 'to the upper gears 8b, from the lower gears 8b' to the lower rollers 8 'via the respective lower shafts 8a', and from the upper gears 8b to the upper rollers 8 via the respective upper axes 8a. This relatively large indirect boost of the rollers, via a single large motor, multiple axes, and multiple gears, adds significantly to the inertia of the system projecting the support cable through the bed of the machine.

Due to this inertia, the response time of the supporting cable feeding apparatus is reasonably low. The configuration shown in Figure 1c requires approximately 230 milliseconds to project the support cable through the bed of the machine. As the machine has a similar operation to step, it will be appreciated that a "bottleneck" at any step of the machine will have a significant overall effect on the speed and overall efficiency of the machine. Consequently, it is desirable to minimize the duration of each step. Apparatus for working or forming cable are described in the patent of E. U. A. No. 6,502,446; Patent of E. U. A. No. 6,490,901; Patent of E. U. A. No. 5,566,564; and Japanese Patent No. 4-319012. Apparatus for feeding cable over short distances in welding machines are described in U.S. Patent No. 3,672,655 and Japanese Patent 55-57381. It is an object of at least the preferred embodiments of the present invention to provide an apparatus for projecting cable which offers more rapid operation than the apparatus described with reference to Figure 1c above, or which will provide at least the public with a useful choice.

BRIEF DESCRIPTION OF THE INVENTION The term "comprising" as used in this specification and the claims means "consisting at least part of"; this is when the statements in this specification and claims are interpreted which include "understanding", the characteristics prefaced by this term in each statement all need to be present but other characteristics may also be present. Related terms such as "comprises" and "understood" are to be interpreted similarly. In accordance with a first aspect of the present invention, there is provided an apparatus for projecting a support cable through a plurality of in-line cables in a fence forming machine, the apparatus comprising three rollers defining a travel path of cable and arranged generally annularly around the travel path of the cable to contact the cable and move the cable along the travel path of the cable under rotation of the rollers, wherein each of the rollers is arranged to be driven directly by a respective motor. Suitably, each motor comprises a housing with a drive shaft extending from the housing, and a roller is mounted on the drive shaft of each motor. Advantageously, each roller comprises a generally arcuate contact surface extending around its perimeter to receive, and make contact with, part of the cable to be projected. The rollers may be biased towards the travel path of the cable, to help maintain contact between the rollers and a cable when it is being moved through the travel path of the cable. The device it preferably comprises a compression spring arranged to push against a member associated with each roller to bias the rollers towards the travel path of the cable. The bias of each roller is advantageously adjustable. An adjuster can be associated with each spring, and configured such that moving the adjuster alters the amount of spring force which skews each roller. Preferably, each motor is an electric servo motor. The rollers may be arranged at approximately 120 degree angles around the cable travel path. The apparatus may comprise more than three rollers disposed generally annularly around the travel path of the cable. According to a second aspect of the present invention, there is provided a fence mesh forming machine comprising: a machine bed arranged to pass a plurality of wires in substantially parallel line through it; and an apparatus as noted in the first aspect previously configured to project a support cable to a plurality of in-line cables. Suitably, the apparatus is configured to rotate the rollers for a predetermined period of time and at a predetermined speed, so as to project the support cable a predetermined distance.

The apparatus can be configured to project the support cable through all the cables in line in the plurality of in-line cables. According to a third aspect of the present invention, there is provided a method for projecting a support cable through a plurality of in-line cables in a fence mesh forming machine comprising a machine bed arranged to pass a plurality of wires. of substantially parallel in-line cables therethrough and an apparatus as noted in the first aspect above, the method comprising feeding a support cable between the rollers of the apparatus, and operating the apparatus for projecting the support cable through a plurality of cables in line. The method may comprise rotating the rollers for a predetermined period of time and at a predetermined speed, so as to project the support cable a predetermined distance. The method may comprise projecting the support cable through all the in-line cables in the plurality of in-line cables. The invention consists of the following and also conceives constructions of which the following provides examples only.

BRIEF DESCRIPTION OF THE DRAWINGS Various embodiments of the invention are described by way of example only, with reference to the accompanying drawings in which: Figures 1a and 1b are perspective views of an existing fence-tying mesh forming machine, which includes an apparatus existing to project the support cable through the bed of the machine; Figure 1c is a perspective view of the drive mechanism of the existing apparatus for projecting the support cable of the machine of Figures 1a and 1b; Figure 2 shows schematically part of a typical fence mesh formed by a machine such as that shown in Figures 1a to 1c; Figure 3 is a front perspective view of an apparatus for projecting cable in accordance with a preferred embodiment of the present invention; Figure 4 is a schematic end view of the apparatus of Figure 3 showing an advantageous orientation of the rollers; Figure 5 is a sectional perspective view of the apparatus of Figure 3; Figure 6 is a detail view showing part of the apparatus of Figure 3; Y Figure 7 is a schematic partial sectional view of a roller and motor of the apparatus of Figure 3.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The present invention has application in a close-knit mesh forming machine such as that shown in Figures 1a and 1b. The general operation of that machine is described in the Patent of E. U. A. No. 6, 668,869, and will not be described in detail here again. The content of the U.S. Patent No. 6,668,869 is incorporated herein by reference in its entirety. Figure 2 shows the travel of the cables through a fence mesh forming machine, such as that shown in Figures 1a-1c. The in-line cables 2 travel in a generally parallel arrangement in a direction indicated by the arrow L. After the in-line cables have traveled a predetermined distance, a support cable 7 is fed through the cables in line in the direction indicated by the arrow S. A support cable attaching assembly can then place and hold the support cable. The support wire could then be cut to a desired length, and the knots indicated by X could be formed in all or most of the cable crossings of the inline support cable. Generally, on each side of the fence mesh, the Support cable could be twisted around the cable in line instead of being connected to it by a knot. An apparatus of the preferred embodiment for projecting a support cable through in-line cables is shown in Fig. 3 and is generally indicated by reference numeral 100. In the machine of the Figures 1a and 1b, the apparatus of Figure 1c could be replaced by the apparatus of the preferred embodiment 100. The apparatus 100 includes a base plate 101 which in the embodiment shown supports three feeding arrangements 103. Each feeding arrangement includes a arm 105 defining a roller housing and which is preferably mounted rotatably relative to the base plate 101 via the respective pivots 107 (see Figure 5 and 6). Mounted for rotation to each arm is a roller 109. Each roller has a rotation shaft 109a which, as shown, can lie substantially parallel to the pivot axis. A cable travel path is formed between the rollers 109 to feed the cable. As can be seen in Figure 7, each roller preferably comprises a center 109c which is received in the bearings 121 in the housing 105. An advantageous arrangement of the rollers 109 in relation to a cable travel path for a support cable 7 shown in Figure 4. Rollers 109 are arranged generally annularly, i.e. radially, around the travel path of cable W to make contact with cable 7 traveling through it from different sides / angles. The rollers are preferably arranged with substantially equal angular spacing around the travel path of the cable W, thus in the embodiment shown the rollers are preferably arranged at approximately an angular spacing of 120 degrees. If four rolls are used, the rolls could preferably be arranged with approximately 90 degree angular spacing. Five rollers could preferably be arranged with approximately an angular spacing of 72 degrees. Each roller preferably has an arcuate contact surface 109b formed on its perimeter to receive and make contact with the portion of the wire 7 to be fed through the travel path of the cable W. This helps to keep the cable in alignment / position correct when it travels through the cable's travel path. The rolls are preferably arranged with substantially co-planar axes of rotation, although this is not essential. It is preferred that the rollers 109 be biased towards the travel path of the cable W as indicated by the arrows B in Figure 4. To achieve this, a biasing device which may be a compression spring 111 for example acts against a part of each support arm 105 distal to the pivot 107 and roller 109. The spring biases that part of the support arm away from the base plate and thus the roller 109 towards the travel path of the cable W. The rollers 109 are thus skewed towards each other, to help maintain contact between the contact surfaces 109b of the rollers and a cable 107 being fed through the travel path of the cable W by movement of the rollers. This also helps to compensate for any discrepancies in the cross section of the cable which can result from manufacturing variations. In a preferred embodiment, the biasing force of each roller is preferably adjustable. In the embodiment shown, adjustment of the bias force acting on the rollers is achieved by turning an adjuster 113 associated with each roller, which alters the compression and thus the biasing force of the spring 111 which skews the roller. The same biased arrangement will preferably be provided for each roll. Other biased provisions could be used if desired. In the embodiment shown, a drive motor indicated generally by the reference number 115 is associated with each roller and is operable to rotate that roller. The rollers 109 are arranged to be driven directly by the respective motors 115. This is, the output of each motor is transferred to the respective roller without additional gears or shafts. Figure 7 shows schematically a partial cross-sectional view of the motor and the roller. As can be seen, the motor comprises a housing 115a and a drive shaft 115b extending from the housing, and the roller is mounted on the drive shaft of the motor. A key (not shown) will usually be used to insert the roller towards the drive shaft. Preferably, the roller is mounted directly on the drive shaft as shown without involving a bushing or similar article, to minimize inertia. The motors 115 are preferably synchronized such that the rotation of the rollers is synchronized. When the motors are operated, the rollers rotate and thus move a cable 7 through the travel path of the cable via contact between the arcuate contact surfaces of the rollers and the cable 7. The motors are preferably electric servo motors. The cable is preferably directed out of the apparatus through an outlet feed nozzle 117 as shown in Figure 3, which is appropriately substantially cylindrical in configuration as shown. As shown in Figure 5, an additional guide 119 which could be generally coaxial with the outlet feed nozzle 117 can be provided to help align the cable 6 with the travel path of the cable W between the rollers. In operation of the machine, the plurality of cables in line 2 will be fed a predetermined distance through the bed of the machine. Once the predetermined distance has been reached, the movement of the cables in line 2 is stopped and the motors 115 of the apparatus 100 of the preferred embodiment are operated to cause the rollers 109 to co-rotate. This causes the support cable 7 to be fed through the cable travel path as a result of frictional engagement with the contact surfaces 109b of the rollers. The speed of rotation of the rollers will be sufficient for the support cable 7 to pass through the output power nozzle 117 and will be projected through the plurality of wires in line. To project the support cable the required distance, the rollers can be rotated for a predetermined time at a predetermined speed, which can be achieved by operating the motors at an appropriate speed for an appropriate period of time. Alternatively, or in addition, one or more detectors could be used to determine when the support cable has been projected the desired distance (such as by determining when a sufficient length of support cable has been fed from the preferred apparatus), at which point the operation of the motors 115 will cease to stop the output power of the support cable. The support cable can then be held by a setter assembly (not shown) and cut to length by a cutting mechanism (not shown), and knots in X will be formed in at least most of the intersections of the cable in the line of the support cable. The ends of the support cables could generally be twisted around the outer line cables. Following this, the wires in line will move again a predetermined distance, and the process will repeat. The foregoing describes the preferred embodiments, and modifications will be made thereto without deviating from the scope of the following claims.

For example, in the embodiment shown and described, each roller is arranged to be directly driven by a respective motor. In some embodiments it is not necessary that all the rollers are driven, and one or more of the rollers could be on a roller which rotates as a result of the movement of the cable through the travel path of the cable. However, it is preferred for optimum performance that each roller be driven directly by a respective motor. The preferred embodiment is described above with reference to support cables projecting in a closely-attached mesh forming machine. However, it will be appreciated that the preferred embodiment has applications for projecting or feeding other types of cables in other types of machines. The motors 115 are described as electric servo motors. Different types of engines could be used, such as hydraulic motors. Nevertheless, electric servo motors are preferred when they have low inertia and fast response times. In addition, the rollers are shown as being generally disk-shaped. However, it will be appreciated that while it is the preferred embodiment, the rollers could be of other shapes such as generally cylindrical for example. In the mode shown, the support cable is projected through all the cables in line in the machine. For some applications, it may be desirable for the support cable to be projected only through some of the cables in line. Additionally, the preferred embodiment is described as having three rollers, however it will be appreciated that four or more rollers can be used, for example, with the four rollers arranged generally annularly around the travel path of the cable. In such a mode, it may be necessary to offset the axes of some of the rollers somewhat so that they may fit around the travel path of the cable. By providing independent direct drive of the roller (s) by the respective motor (s), the inertia of the apparatus is reduced on the apparatus shown in Figure 1c, due to the elimination of additional gears, shafts, etc. The result is that the projection speed of the support cable is improved over the apparatus of Figure 1c. Additional speed improvements are obtained in the preferred embodiment using three or more rollers arranged generally annularly around the travel path of the cable, each of which is driven directly by a respective motor. This is because the rollers and motors can be smaller and thus have less inertia than in the apparatus of Figure 1c. The apparatus of the preferred embodiment can project the support cable through the bed of the fence mesh forming machine shown in Figures 1a and 1b in approximately 90 milliseconds. Using the apparatus of the preferred modality, productivity Overall of the machine of Figure 1a and 1b can be improved by approximately 16%.

Claims

NOVELTY OF THE INVENTION CLAIMS

1. - An apparatus for projecting a support cable through a plurality of cables in line in a fence mesh forming machine, the apparatus characterized in that it comprises three rollers defining a cable travel path and arranged generally annularly around the path travel of the cable to make contact with the cable and move the cable along the travel path of the cable under rotation of the rollers, wherein each of the rollers is arranged to be driven directly by a respective motor.

2. The apparatus according to claim 1, further characterized in that each motor comprises a housing with a drive shaft extending from the housing, and wherein a roller is mounted on the drive shaft of each motor.

3. The apparatus according to claim 1 or 2, further characterized in that each roller comprises a generally arcuate contact surface extending around its perimeter to receive, and make contact with, part of the cable to be projected.

4. The apparatus according to any of claims 1 to 3, further characterized in that the rollers are biased towards the travel path of the cable, to help maintain contact between the rollers and a cable when it is being moved through the travel path of the cable.

5. The apparatus according to claim 4, further characterized in that it comprises a compression spring arranged to push against a member associated with each roller to bias the rollers towards the travel path of the cable.

6. The apparatus according to claim 5, further characterized in that the bias of each roller is adjustable.

7. The apparatus according to claim 6, further characterized in that an adjuster is associated with each spring, and is configured such that moving the adjuster alters the amount of spring force which skews each roller.

8. The apparatus according to any of the preceding claims, further characterized in that each motor is an electric servo motor.

9. The apparatus according to any of claims 1 to 8, further characterized in that the rollers are arranged at angles of approximately 120 degrees around the travel path of the cable.

10. The apparatus according to any of claims 1 to 8, further characterized in that it comprises more than three rollers arranged generally annularly around the travel path of the cable.

11. - A fence mesh forming machine characterized in that it comprises: a machine bed arranged to pass a plurality of substantially parallel line cables through it; and an apparatus according to any of the preceding claims configured to project a support cable into a plurality of in-line cables.

12. The fence mesh forming machine according to claim 11, further characterized in that the apparatus is configured to rotate the rollers for a predetermined period of time and at a predetermined speed, to project the support rope a predetermined distance.

13. The fence mesh forming machine according to claim 11 or 12, further characterized in that the apparatus is configured to project the support cable through all the cables in line in the plurality of cables in line.

14. A method for projecting a cable in support through a plurality of cables in line in a fence mesh forming machine characterized in that it comprises a machine bed arranged to pass a plurality of cables in line substantially parallel through of these and an apparatus according to any of claims 1 to 10, the method comprises feeding a support cable between the rollers of the apparatus, and operating the apparatus for projecting the support cable through a plurality of in-line cables.

15. - The method according to claim 14, further characterized in that it comprises rotating the rollers for a predetermined period of time and at a predetermined speed, for projecting the support cable a predetermined distance.

16. The method according to claim 15, further characterized in that it comprises projecting the support cable through all the cables in line in the plurality of cables in line.

17. A method for projecting a support cable through a plurality of in-line cables in a fence mesh forming machine further characterized in that it comprises a machine bed arranged to pass a plurality of substantially parallel in-line cables through of this and an apparatus according to any of claims 1 to 13; the method comprises feeding a support cable between the rollers of the apparatus, and operating the apparatus for projecting the support cable through a plurality of in-line cables. The method according to claim 17, further characterized in that it comprises rotating the rollers for a predetermined period of time and at a predetermined speed, so as to project the support cable a predetermined distance. 19. The method according to claim 18, further characterized in that it comprises projecting the support cable through all cables in line in the plurality of cables in line.