Rotary anvil construction

Abstract

A rotary anvil construction is provided which is comprised of a cylindrical anvil which has a die-cutting mat which is readily attached thereon and detached therefrom through the use of a locking wedge which provides its locking action by rotation thereof about an axis substantially parallel to the axis of said construction.

Description

BACKGROUND OF THE INVENTION

Rotary anvil constructions which utilize die-cutting mats and are attached by various means against the outside surfaces of associated anvils are in wide use throughout industry. Many of these previously proposed anvil constructions are unnecessarily complex and expensive while others have mats which are very difficult to install and remove from their associated rotary anvils.

In U.S. Pat. No. 3,739,675, applicants have proposed a simple rotary anvil construction which overcomes many of the deficiencies of the previously proposed anvil constructions; however, applicants have found that it is desirable to provide a rotary anvil construction in which the wedge used to hold the die-holding mat can be installed into position more easily yet without impairing the ability of the mat to be held in position in a firm and secure manner.

SUMMARY

This invention provides an improved rotary anvil construction which employs a die-cutting mat which is readily installed on and removed from an associated rotary anvil in a minimum of time. The die-cutting mat is held on its rotary anvil so that a single rectilinear line contact is provided between its end portions and such line extends longitudinally across the anvil. The rotary anvil construction employs a locking wedge which may be provided as a separate member or as an integral part of the rotary anvil and such wedge is locked in position to fasten the mat in position by rotation thereof about an axis substantially parallel to the axis of the construction.

Other details, uses, and advantages of this invention will be readily apparent from the exemplary embodiments thereof presented in the following specification, claims, and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings show present exemplary embodiments of this invention, in which

FIG. 1 is a fragmentary perspective view of a rotary anvil construction of this invention having an easily installed and removed die-cutting mat;

FIG. 2 is an enlarged fragmentary end view taken essentially on the line 2--2 of FIG. 1;

FIGS. 3, 4, 5, and 6 are fragmentary perspective views illustrating a series of steps which may be employed to install and lock the die-cutting mat of FIG. 1 in position;

FIG. 7 is a fragmentary perspective view illustrating another exemplary embodiment of rotary anvil construction of this invention which has a wedge thereof rotatably supported by a U-shaped insert which is detachably fixed to the rotary anvil;

FIG. 8 is an exploded perspective view of the U-shaped member of FIG. 7 with its wedge and support means for such wedge;

FIG. 9 is a fragmentary perspective view similar to FIG. 4 illustrating one of the first of a series of method steps which may be employed to install and lock the die-cutting mat of FIG. 7 in position;

FIG. 10 is an enlarged view taken essentially on the line 10--10 of FIG. 9; and

FIG. 11 is a view similar to FIG. 10 illustrating the rotatable locking wedge rotated into its locking position.

DESCRIPTION OF ILLUSTRATED EMBODIMENTS

Reference is now made of FIG. 1 of the drawing which illustrates one exemplary embodiment of a rotary anvil construction 20 of this invention. The anvil construction 20 is particularly adapted to be used with an associated rotary cutter or cylinder (not shown) having cutting means or blades thereon and the anvil construction 20 serves as a backup allowing the blades of such rotary cutter to be urged against a workpiece which is to be cut, such as a sheet of either plain or corrugated paper, or other suitable sheet material so that the cutting may be achieved without jagged edges.

The rotary anvil construction 20 comprises a rotary anvil or cylinder 21 having an outer substantially cylindrical surface 22 and having a pair of spaced holding surfaces 23 extending inwardly from the surface 22 and the surfaces 23 define opposed side walls of longitudinal groove 24 which extends along the full length of the cylinder 21 in substantially parallel relation to the central longitudinal axis 25 of such cylinder. The cylinder 21 may be made of any suitable material and is preferably made of a rigid material such as metal.

The construction 20 comprises a die-cutting mat 26 which has an inside surface 27, a pair of opposite end portions 30, and a pair of locking lips or flanges 31 and 32, FIG. 2. Each flange 31 and 32 extends from the terminal end of its associated end portion 30 and the flanges 31 and 32 have channels 33 and 34 respectively therein each extending across the full width of its flange with each channel being particularly adapted to receive at least a portion of a locking wedge 35 which is used to lock the mat 26 in position.

One of the channels, channel 34 of this example, has a cross-sectional configuration which corresponds to the cross-sectional configuration of the wedge and channel 34 is slightly larger in area than the cross-sectional area of wedge which allows easy insertion of the wedge along the full length of the channel 34 and hence the flanges 31 and 32. The other channel 33 has a cross-sectional area which corresponds to approximately one half of the cross-sectional area of the wedge 35 and the channels 33 and 34 are made and sized so that with the wedge 35 arranged with its major axis substantially perpendicular to the holding surfaces 23 opposed ends thereof, defining its comparatively large dimension 36, urge the flanges 31 and 32 tightly against the holding surfaces 23 to lock the mat 26 firmly against the outside cylindrical surface 22 of cylinder 21. Simultaneously with this locking action the wedge 35 moves outer edges 37 of the mat 26 firmly against each other to provide a single line junction or contact 40 therebetween, see FIG. 1, and such line contact comprises a rectilinear line contact. During the process of wedging the flanges 31 and 32 firmly in position, it will be seen that the wedge 35 partially compresses the lower portions of the flanges 31 and 32, as illustrated at 41 in FIG. 2, while urging and slightly compressing the edges 37 against each other to assure the provision of the single line contact 22 and such single line coincides substantially precisely (i.e., free of bulges or indentations) with a right circular cylindrical outside surface 42 defined by the outside surface of the mat 26 once it is installed in position, see FIG. 6.

The cylindrical rotary anvil or cylinder 21 has an insert 43 of substantially U-shaped cross-sectional configuration fixed within the peripheral cylindrical outside surface 22 of the anvil 21 and extending the full length of such anvil, see FIGS. 1-4. The insert 43 has a U-shaped configuration, when viewed from an end thereof or in cross-section, a defined by a bight 44 and a pair of outwardly extending leg portions 45 with the leg portions 45 having outer surface portions 46 which comprise the substantially cylindrical surface 22 of cylinder 21. The insert 43 has a pair of spaced transverse planar surfaces each adjoining an associated one of the surface portions 46 and such planar transverse surfaces define the holding surfaces 23 of cylinder 21.

The holding surfaces 23 diverge toward the longitudinal axis 25 of the cylinder 11 and are arranged in what might be considered a dovetailed manner whereby once the wedge 35 is installed in position the mat 26 is held firmly against the cylinder 21 for normal operation of the anvil construction 20.

As seen from FIG. 2, the flanges 31-32 extend substantially perpendicularly from the end portions 30 and each flange 31-32 has a height 47 which is less than the depth 50 of the groove 24, FIG. 4, so once the wedge 35 positions the flanges 31-32 in the manner illustrated in FIG. 6, the flanges are urged against the diverging holding surfaces 23 and the flanges 31-32 and wedge 35 define a dovetailed structure which cooperates with the dovetailed arrangement of the holding surfaces 23 yet there is minimal contact between the terminal ends 51 of the flanges 31-32 and the fixed insert 43 whereby there is minimum contact between the flange ends 51 and cylinder 21. This minimum contact, if any, is only at corner portions 52 of ends 51 and assures that there is no tendency for forces to act in a direction perpendicular the longitudinal axis 25 of cylinder 21 whereby there is no tendancy to move the flanges radially outwardly away from such longitudinal axis, see FIG. 2.

The mat 26 has its inside surface 27 and each of the flanges 31-32 has its channel 33--34 extending inwardly therein from its outer surfaces 54. Each channel 33-34 extends across the full width of its flange and is spaced from the inside surface 27 by a distance indicated at 55. The channels 33-34 are arranged in aligned relation with the mat 26 installed in position and cooperate to receive the wedge 35 therethrough so that wedge 35 tightens and locks the mat against the anvil 21 and simultaneously moves the outer edges 37 in position to define the single line contact 40 between edges 37.

The mat 26 has a bottom sheet-like portion or backing sheet 56 which defines the portion thereof which is held against the cylindrical surface 22 of the cylinder 21 and the sheet-like portion 56 is preferably made of a suitable metallic material and has an exposed surface which defines the inside surface 27 of the mat 26. The metal backing sheet 56 assures that the mat 26 maintains its form under all operating and storage conditions; however, it will be appreciated that the mat 26 need not necessarily have the backing sheet 56 provided as an integral part thereof whereby it may be comprised entirely of a suitable elastomeric material which may be reinforced with a suitable woven material or other suitable reinforcing means.

The rotatable locking wedge 35 of this exemplary embodiment of the invention has a roughly elliptical cross-sectional configuration and is shown as being of solid cross section throughout; however, it will be appreciated that such wedge may be tubular having a uniform wall thickness about its outer periphery or may be tubular having a right cylindrical bore extending therethrough.

The channel 34 provided in the flange 32 also has a roughly elliptical configuration when viewed from an end thereof or when viewed at any cross section therealong perpendicular to its longitudinal axis and the elliptical configuration of the channel 34 is such that the roughly elliptical wedge 35 may be easily inserted therealong and once such wedge 35 has been extended along the full length of the channel 34 it is ready to be locked in position simply by rotation thereof approximately 90.degree. as will be described in more detail subsequently. It will also be seen that the channel 33 in the flange 31 has what may be considered a substantially semielliptical end or cross-sectional configuration.

By the mere fact that the wedge 35 is substantially elliptical in cross-sectional configuration, it has its comparatively large dimension 36 along what may be considered its major axis and a comparatively smaller or narrower dimension 60 along its minor axis with the major and minor axes being in accordance with known nomenclature of an ellipse.

The flanges 31-32 are made as an integral part of the mat 26 and of the same compressible resilient elastomeric material; and, as seen in FIG. 2, the flanges 31-32 have cooperating recess means designated generally by the reference numeral 61 adjoining at least one end of the channels 33 and 34 and the recess means 61 in this example is shown as a pair of substantially semicylindrical cutouts 62 in each flange 31-32. The recess means 61, comprised of semicylindrical cutouts 62, is particularly adapted to receive a tool, such as a tool T illustrated in FIG. 5, to provide 90.degree. rotation of the elliptical wedge to provide the unique locking action as will be described subsequently. It will be appreciated that the recess means 61 may be provided only at one end of the cooperating flanges 31-32 or at both ends thereof.

Having presented the detailed description of the anvil construction 20, the presentation will now proceed with the manner in which the mat 26 may be simply installed on the cylinder or anvil 21 and for this description particular reference is made to FIGS. 2-5 of the drawings. The mat is positioned as illustrated in FIG. 3 of the drawings with one of its flanges, shown as the flange 31, positioned within the groove 24 whereupon the mat 26 is wrapped around cylindrical surface 22 so that its other flange 32 is arranged above groove 24 in the manner illustrated in FIG. 3. The other flange 32 is then inserted in position within groove 24 in the manner illustrated in FIG. 4 whereby the flanges 31-32 are arranged within groove 24 with their respective channels 33 and 34 in substantially aligned relation. The elliptical wedge 35 is preferably slightly smaller in cross-sectional area or very nearly the same cross-sectional area as the channel 34 so that it may be easily axially inserted in channel 34 until it extends the full length of the flanges 31-32 and an end portion 63 thereof is within recess means 61.

As previously mentioned, the wedge 35 has a comparatively small dimension 60 across its minor axis and thus is easily adapted to be initially arranged between the flanges 31-32 and indeed in this example extends along the comparatively larger elliptical channel 34. The wedge 35 is adapted to be rotated approximately 90.degree. to position its major axis and hence the comparatively large dimension 36 thereof substantially perpendicular to the holding surfaces 23 thereby urging the flanges 31-32 tightly against such holding surfaces to tighten and lock the mat 26 against the rotary anvil 21.

The tool T has an end portion 64 which is of roughly tubular elliptical cross-sectional configuration which is adapted to surround end portion 63 of the wedge 35 and the end 64 is adapted to be received within the recess means 61 whereupon the end of a handle 65 of the tool T is grasped and the tool T rotated either clockwise or counterclockwise roughly 90.degree. to thereby urge the flanges 31-32 tightly against the holding surfaces 23 thereby partially compressing the flanges 31-32 and locking the mat 26 in position.

It is a simple matter to remove the mat 26 by, in essence, following the reverse of the above-described procedure whereupon tool T is used to again rotate wedge 35 through an angular increment of roughly 90.degree. enabling easy extraction of such wedge from within the elliptical channel 34 and such extraction may be achieved by engaging the end of the wedge 35 with a screw driver, or the like, until a sufficient length of the wedge 35 is pushed out from the channel 34 allowing easy grasping thereof and extraction of such wedge. It will be appreciated that the wedge 35 has a length substantially equal to, though less than, the corresponding dimension of the flanges 31-32.

Another exemplary embodiment of this invention is illustrated in FIGS. 7-11 of the drawings. The anvil construction of FIGS. 7-11 is very similar to the anvil construction 20; therefore, such anvil construction will be designated generally by the reference numeral 20A and parts thereof which are similar to corresponding parts of the anvil construction 20 will be designated by the same reference numeral as in the anvil construction 20 also followed by the letter designated A and not described again in detail. Only those component parts which are substantially different from corresponding parts of the anvil construction 20 will be designated by a new reference numeral also followed by the letter designation A and described in detail.

The main difference between the anvil construction 20 and the anvil construction 20A is that instead of having a rotatable locking wedgee which is a separate removable component part as is wedge 35, the anvil construction 20A has a wedge which is also designated generally by the reference numeral 35A but which is supported in a fixed position in the groove 24A of the rotary anvil 21A and is a part of its substantially U-shaped insert 43A, see FIGS. 7 8 and 10. The insert 43A extends substantially the full axial dimension of the rotary anvil or cylindrical 21A and such U-shaped insert is defined by a bight 44A and a pair of outwardly extending leg portions 45A extending from opposite ends of such bight.

The U-shaped insert 43A is adapted to be and is detachably fixed to the rotary anvil 21A and has means designated generally by the reference numeral 66A rotatably supporting the wedge 35A in a fixed position on the U-shaped insert 43A; and, with the insert 43A being fixed on the anvil 21A such means 66A rotatably supporting the wedge 35A effectively rotatably supports wedge 35A in a fixed position on the anvil 21A.

The means 66A rotatably supporting the wedge 35A comprises a plurality of post-like members 67A which may be provided as either an integral part of the member 43A or be suitably detachably fixed to its bight 44A; and, the postlike members 67A extend from the central part of the bight 44A and each has bearing means 70A fixed thereto. The bearing means 70A may have a suitable anti-friction surface 71A which is particularly adapted to receive the outside surface of the rotatable substantially right circular cylindrical member or rod 72A.

The rod 72A carries the wedge 35A and in this example, it will be seen that the wedge 35A is comprised of a plurality of sections or lengths each designated by the same reference numeral 73A even though sections 73A are of different lengths. The sections 73A are suitably fixed at spaced intervals along the rod 72A by any suitable means such as detachable set screws, adhesive means, welding, or the like.

It is a simple matter to install the die cutting mat 26A in position and installation is substantially similar to the installation of the mat 26 and in the manner illustrated in FIGS. 3-5. In particular, the flanges 31A and 32A are installed in position in the manner illustrated in FIG. 9 whereupon it will be seen that the wedge 35A and hence component portions 73A are arranged so that the minor axis of the rotatable fixed wedge 35A is initially arranged between flanges 31A-32A with the minor axis substantially perpendicular to the flanges and in a fixed position. The tool T is again employed by inserting the end 64 thereof around end portion 63 of the wedge 35A whereupon tool handle 65 is grasped and rotated either clockwise or counterclockwise 90.degree.. in a similar manner as described previously for the construction 20 whereupon the comparatively large dimension 36A, i.e., along the major axis the elliptical wedge 35A, is urged against the flanges 31A and 32A urging such flanges tightly against the holding surfaces 23A to tighten and lock the mat 26A against the anvil 21A while simultaneously moving associated outer edges 37A of the mat firmly against each other whereby a single line contact 40A is provided.

Removal of the mat 26A is achieved following the reverse procedure whereupon the tool T is installed in position and the rotatable elliptical wedge 35A is rotated 90.degree. whereby, in essence, the small dimension 60A along the minor axis of the rotatable wedge 35A is arranged perpendicular to the holding surfaces 23A enabling the flanges 31A and 32A to be easily withdrawn from the groove 24A and the mat 26A removed.

It should be noted that the flanges 31A-32A of the mat 26A have substantially identical channels which will be designated by the reference numeral 70A and such channels are of roughly semielliptical configuration when viewed from an end or at any cross section therealong.

In this disclosure of the invention, the rotatable wedge 35 and 35A have been illustrated and described as having a substantially elliptical cross-sectional configuration; however, it is to be understood that such wedges may have any other suitable cross-sectional configuration provided that each wedge, in essence, has an eccentric arrangement with a major and a minor axis and with the dimension along the major axis thereof being large when compared to the dimension along the minor axis. Such a wedge would then be positioned with its small dimension extending between associated flanges of the die-cutting mat whereupon such a wedge would then be rotated roughly 90.degree., or other suitable angular increment, bringing its larger dimension into camming engagement against surface portions of the flanges of such mat to provide a unique locking action simply by rotation of the rotatable wedge. The unlocking of the wedge is also achieved by simple rotation thereof facilitating easy removal of such wedge.

In this disclosure of the invention, the wedges 35 and 35A have been shown and described as having comparatively smooth outside surfaces of arcuate or curvilinear configuration; however, it will be appreciated that the rotatable wedge need not necessarily be as shown herein but may be of approximately rectangular cross-sectional configuration defined by a series of cooperating planar surfaces.

In this disclosure, the wedges 35 and 35A have been shown as being rotatably cammed into locking engagement using a tool T which in each instance has a portion 64 which surrounds an associated end portion of the wedge and a roughly 90.degree. rotation is provided. However, it will be appreciated that either wedge 35 or 35A may be provided with slots or the like therein which may be adapted to receive a suitable tool therewithin thereby eliminating the need to provide a recess means such as recess means 61 or 61A in the flanges of the associated mats either 26 or 26A. For example, such a slotted wedge may have slots suitable for receiving Phillips head type screw driver or an Allen head type wrench.

In this disclosure of the invention the rotary anvil or cylinder 21 of the anvil construction 20 is shown provided with insert 43 which has holding surfaces 23 provided on such insert; however, it will be appreciated that the surfaces 23 may be provided on the cylinder 21 directly without requiring an insert.

Similarly in the anvil construction 20A the insert 43A may be eliminated, if desired, and means 66A used to support the wedge 35A in a fixed position directly on the cylinder 21A.

The mat of this invention may be made of any suitable elastomeric material which is capable of being used in association with a rotary cutter; and, it has been found such mat may be of any suitable polymer such as polyurethane, or a suitable rubber compound whether natural or synthetic rubber.

While present exemplary embodiments of this invention, and methods of practicing the same, have been illustrated and described, it will be recognized that this invention may be otherwise variously embodied and practiced within the scope of the following claims.

Claims

What is claimed is:

1. In combination: a rotary anvil having an outer substantially cylindrical surface and having a pair of spaced holding surfaces extending inwardly from said cylindrical surface and defining opposed walls of a longitudinal groove in said anvil, a die-cutting mat made of a compressible resilient elastomeric material attached against said anvil, said mat comprising a main central portion having opposite end portions provided with a pair of identical locking flanges extending from said end portions and being received within said groove, and a wedge between said flanges, said wedge having a major and a minor-sectional axis, said wedge having a comparatively large dimension across its major axis and being arranged substantially perpendicular said holding surfaces and thereby urging said flanges tightly against said holding surfaces to tighten and lock said mat against said anvil while simultaneously moving associated outer edges of said mat firmly against each other to provide a single line contact therebetween, said wedge having a comparatively small dimension across its minor axis and thus being adapted to be initially arranged between said flanges with its minor axis substantially perpendicular thereto, said wedge being adapted to be rotated approximately 90.degree. to position its major axis and comparatively large dimension in said perpendicular arrangement.

2. A combination as set forth in claim 1 in which said flanges extend substantially perpendicularly from said end portions and each of said flanges has a channel therein extending across its full width which is particularly adapted to receive at least a portion of said wedge.

3. A combination as set forth in claim 2 in which one of said channels has a configuration which corresponds to and is larger in cross-sectional area than the cross-sectional area of said wedge to allow easy insertion of said wedge axially along said one channel and the other of said channels has a configuration which corresponds to and is approximately one-half of the cross-sectional area of said wedge, so that with said wedge rotated with its major axis substantially perpendicular said holding surfaces said comparatively large dimension thereof urges said flanges tightly against said holding surfaces.

4. A combination as set forth in claim 1 and further comprising means rotatably supporting said wedge in a fixed position in said groove of said anvil.

5. A combination as set forth in claim 1 and further comprising an insert of substantially U-shaped cross-sectional configuration fixed within the peripheral outline of said anvil and extending the full axial dimension thereof, said insert having a pair of surface portions comprising said substantially cylindrical surface and having a pair of planar surfaces each adjoining an associated one of said surface portions and defining said holding surfaces of said longitudinal groove.

6. A combination as set forth in claim 5 in which said U-shaped insert has means rotatably supporting said wedge in a fixed position on said anvil.

7. A combination as set forth in claim 6 in which said U-shaped support has a bight and a pair of legs extending outwardly from opposite ends of said bight, said means rotatably supporting comprising a plurality of spaced post-like members extending from the central part of said bight.

8. A combination as set forth in claim 3 in which said wedge has a roughly elliptical cross-sectional configuration, one channel has a corresponding elliptical cross-sectional configuration and said other channel has a substantially semielliptical cross-sectional configuration.

9. A combination as set forth in claim 2 in which each of said channels has a substantially semielliptical cross-sectional configuration across its full width which is particularly adapted to receive at least a portion of said wedge and said wedge has an elliptical cross-sectional configuration.

10. A combination as set forth in claim 2 in which said flanges are made as an integral part of said mat of the same compressible resilient elastomeric material and said flanges have cooperating recess means adjoining at least one end of said channels, said recess means being adapted to receive a tool used to provide said 90.degree. rotation of said wedge.

11. A combination as set forth in claim 10 in which said recess means is in the form of a pair of substantially semicylindrical cutouts in each flange.

12. A combination as set forth in claim 1 in which said wedge is comprised of a plurality of spaced substantially semielliptical sections extending across the full length of said rotary anvil.

13. A combination as set forth in claim 2 in which said planar holding surfaces diverge toward a longitudinal axis extending through said anvil in a dovetailed manner.

14. A combination as set forth in claim 2 in which said wedge is of solid substantially elliptical cross-sectional configuration throughout its length.

15. A combination: a rotary anvil having an outer substantially cylindrical surface and having a pair of spaced holding surfaces extending inwardly from said cylindrical surface and defining opposed walls of a longitudinal groove in said anvil, a die-cutting mat made of a compressible resilient elastomeric material attached against said anvil, said mat comprising a main central portion having opposite end portions provided with a pair of identical locking flanges extending from said end portions and being received within said groove, a wedge between said flanges, said wedge having a major and a minor cross-sectional axis, said wedge having a comparatively large dimension across its major axis and being arranged substantially perpendicular said holding surfaces and thereby urging said flanges tightly against said holding surfaces to tighten and lock said mat against said anvil while simultaneously moving associated outer edges of said mat firmly against each other to provide a single line contact therebetween, said wedge having a comparatively small dimension across its minor axis and thus being adapted to be initially arranged between said flanges with its minor axis substantially perpendicular thereto, said wedge being adapted to be rotated approximately 90.degree. to position its major axis and comparatively large dimension in said perpendicular arrangement, and an insert of substantially U-shaped cross-sectional configuration fixed within the peripheral outline of said anvil and extending the full axial dimension thereof, said insert having a pair of surface portions comprising said substantially cylindrical surface and having a pair of planar surfaces each adjoining an associated one of said surface portions and defining said holding surfaces of said longitudinal groove.

16. A combination as set forth in claim 15 in which said U-shaped insert has means rotatably supporting said wedge in a fixed position on said anvil.

17. A combination as set forth in claim 16 in which said flanges extend substantially perpendicularly from said end portions and have a height which is less than the depth of said groove so that said wedge positions said flanges against said diverging holding surfaces with minimum contact between the terminal ends of said flanges and said anvil.

18. A combination as set forth in claim 17 in which said mat has an inside surface and each of said flanges has a channel therein extending across its full width and spaced from said inside surfaces with each of said channels receiving a portion of said wedge therein.

19. A combination as set forth in claim 18 in which said U-shaped support has a bight and a pair of legs extending outwardly from opposite ends of said bight, said means rotatably supporting comprising a plurality of spaced post-like members extending from the central part of said bight.

20. A combination as set forth in claim 19 in which means rotatably supporting comprises a rod extending substantially the full length of said anvil while being rotatably supported by said post-like members and said wedge is comprised of a plurality of spaced sections detachably fixed around said rod adjacent said post-like members.