CA1180168A - Apparatus for forming an annular groove in the end of cast concrete pipe - Google Patents
Apparatus for forming an annular groove in the end of cast concrete pipeInfo
- Publication number
- CA1180168A CA1180168A CA000401505A CA401505A CA1180168A CA 1180168 A CA1180168 A CA 1180168A CA 000401505 A CA000401505 A CA 000401505A CA 401505 A CA401505 A CA 401505A CA 1180168 A CA1180168 A CA 1180168A
- Authority
- CA
- Canada
- Prior art keywords
- rotor
- header
- pressure head
- annular
- jacket
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000004567 concrete Substances 0.000 title claims abstract description 16
- 230000006872 improvement Effects 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000012530 fluid Substances 0.000 claims description 2
- 230000002093 peripheral effect Effects 0.000 claims 1
- 230000000284 resting effect Effects 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 4
- 238000005266 casting Methods 0.000 abstract description 3
- 230000009969 flowable effect Effects 0.000 abstract description 2
- 238000009740 moulding (composite fabrication) Methods 0.000 description 9
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000002028 premature Effects 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 208000008103 Amniotic Band Syndrome Diseases 0.000 description 1
- 229910000760 Hardened steel Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Manufacturing Of Tubular Articles Or Embedded Moulded Articles (AREA)
Abstract
ABSTRACT
Mechanism is provided for rotating the upper header ring that is included in a mold for casting concrete pipe by a process in which the mold includes a core, usually of cylin-drical section, standing on a support with its major axis upright and surrounded by a jacket to leave a space into which flowable concrete is introduced. The upper header ring has an interior annular ring which provides the groove in the end of the pipe. The present invention provides mechanism for ro-tating the header ring to "trowel" the pipe groove.
Mechanism is provided for rotating the upper header ring that is included in a mold for casting concrete pipe by a process in which the mold includes a core, usually of cylin-drical section, standing on a support with its major axis upright and surrounded by a jacket to leave a space into which flowable concrete is introduced. The upper header ring has an interior annular ring which provides the groove in the end of the pipe. The present invention provides mechanism for ro-tating the header ring to "trowel" the pipe groove.
Description
.~ 8 APPAR~TUS FOR FORMING AN ANNULAR GROOV~ IN
_ THE END OF CAST CONCRETE PIPE
_ The invention pertains to the manufacture of concrete pipe and more particularly to that phase thereof that in-cludes the finishing of the ends of the pipe for ma~ing with like sections when assembled, as for use in conducting fluids, such as water in drainage systems and the like. Opposite ends of the pipe are conventionally formed as male and female ends, respectively, and, for the purpose of improving the connection between the male end of one pipe and the female end of its neignbor, resort has been had heretofore to the provision in the male end of an annular groove into which an appropriate seal is fitted during installation of the pipes end to end.
In the past, the groove has been formed by a header ring of clam shell character, each half containing one-half of the groove-forming ring, and the halves were selectively opened and closed during and after the casting operation. It was also known to oscillate the clam shell to improve the groove.
The present invention provides an improvement in the form-ing of the groove in that the header ring is continuous and the groove-forming ring is removable from the interior of the header ring, so as to remain with the pipe and in the formed groove whèn the header ring is removed during or after strip-ping of the form from the cast pipe. The groove-forming ring is split in its circumference so as to be capable of being "sprung" for ultimate removal from the groove. The header and groove-forming ring are rotated in unison by a header rotor and drive mechanism therefor. It is a further feature that the rotor is connected to a pressure head for vertical movement toward and away from the pipe section in process. rrhe rotor has an annular row of teeth by means of which the rotor may be sprocket-driven by a small motor, the rotation being uni-directional and preferably at least a full revolution so as to completely trowel the groove in the pipe end.
~$
_ THE END OF CAST CONCRETE PIPE
_ The invention pertains to the manufacture of concrete pipe and more particularly to that phase thereof that in-cludes the finishing of the ends of the pipe for ma~ing with like sections when assembled, as for use in conducting fluids, such as water in drainage systems and the like. Opposite ends of the pipe are conventionally formed as male and female ends, respectively, and, for the purpose of improving the connection between the male end of one pipe and the female end of its neignbor, resort has been had heretofore to the provision in the male end of an annular groove into which an appropriate seal is fitted during installation of the pipes end to end.
In the past, the groove has been formed by a header ring of clam shell character, each half containing one-half of the groove-forming ring, and the halves were selectively opened and closed during and after the casting operation. It was also known to oscillate the clam shell to improve the groove.
The present invention provides an improvement in the form-ing of the groove in that the header ring is continuous and the groove-forming ring is removable from the interior of the header ring, so as to remain with the pipe and in the formed groove whèn the header ring is removed during or after strip-ping of the form from the cast pipe. The groove-forming ring is split in its circumference so as to be capable of being "sprung" for ultimate removal from the groove. The header and groove-forming ring are rotated in unison by a header rotor and drive mechanism therefor. It is a further feature that the rotor is connected to a pressure head for vertical movement toward and away from the pipe section in process. rrhe rotor has an annular row of teeth by means of which the rotor may be sprocket-driven by a small motor, the rotation being uni-directional and preferably at least a full revolution so as to completely trowel the groove in the pipe end.
~$
- 2 ~
~8~
In the Drawings:
Fig. 1 is an elevation, with parts omitted and partly in cross section to better illustrate the construction.
FigO 2 is a plan as seen generally along the line 2-2 of Fig. 1.
Fig. 3 is a bottom view of the rotor for turning the tongue trowel.
Fig. 4 is an enlarged edge view of the chain drive for the rotor.
Fig. 5 is an enlarged fragmentary section showing how the chain is affixed to the rotor.
Fig. 6 is an elevation as seen along the line 6-6 of Fig. 5.
Fig. 7 is a fragmentar~ view showing the motor~sprocket-chain drive for the rotor.
Fig. 8 is an enlarged fragmentary sectional view showing the header ring and its groove-forming ring.
Fig. 9 is a reduced plan of the snap ring ~or the top header ring.
In Fig. l, the numeral 10 designates a floor or e~uivalent support on which a casting mold or form unit 12 is supported, being carried by its lower end. The form here is cylindrical and its long axis is vertical. As i5 typical, the form includes an inner core (not shown) surrounded by a steel jacket 14 having its upper end encircled and reinforced by a steel band 16. The an-nular space between the core and the jacket receives flowable con-crete to form a section of pipe 18. ~ top or upper header ring 20 is placed on top of the upper end of the as-yet unset concrete and this ring is shaped so as to give the upper end of the pipe a somewhat annular tapered form of reduced diameter as respects the basic diameter of the pipe. As is known in the art, this end is the male end and fits into the female end of a neighboring pipe section when the pipe is laid. The lower end of the pipe section appearing here is formed as a bell or female end, the formation following known design and processes.
The form is embraced from above by processing structure in-cluding a pair of upright guide members 22 which are mounted on the floor, rising at diametrically opposite sides of the form.
Each guide member slidably carries an upright slide 24 and these slides are rigidly cross-connected by a transverse member spaced above the form. A pressure head 26 of generally circular con-figuration is interposed horizontally between the cross member 24 and the top of the form and is connected to a plurality o~
hydraulic or air cylinder and piston units 28, the connections being effected as at 30 (Fig. 2). The cylinders of these units are carried by the cross member 24 and retraction and extension of the pistons causes raising and lowering of the pressure head.
The pressure head applies down pressure to the top header ring 20 and holds the ring in place during settling, etc., of the con-crete, conventionally accomplished by vibrators or the like (not shown~. Diametrically opposed portions of the pressure head are controlled or guided by projections 32 cooperating with the slides 24 to maintain the attitude of the pressure head during its ver-tical movement.
As best shown in Figs. 8 and 9, the top ring 20 carries aninternal groove-forming ring 34, having a radial split at 36 and detachably secured within the top ring by a plurality of recessed bi8 cap screws 38 via holes 39 in the ring 34 and tapped bores in the ring 20. The purpose of this ring is to form an annular groove in the top or male end of the pipe, as at 40 in Fig. 8. ~s will be understood from this Figure, the ring 34 is released from the header ring by removal of the cap screws, leaving the snap ring in place in the pipe groove as the top ring is removed upwardly.
Because of the split at 36, the ring 34 can be easily removed from the groove after the concrete has set, etc.
It is a feature of the invention that the top ring may be rotated about the axis of the pipe section during the forming of the section. For this purpose, there is journaled in and below the pressure head, by a central bearing 42 of any suitable nature, a circular rotor 44. This rotor has, rigid on its under side, a plurality of radially elongated driving ribs 46 (Fig. 3). The top ring 20 has a like plurality of upstanding lugs 48 rigid thereon. In the present case, there are three lugs and three ribs. The purpose of the elongated ribs is to enable the rotor to accommodate rop rings of different diameters, it being clear that smaller rings will have their lugs on a smaller circle than larger top rings. This improves the versatility of the apparatus.
Clearly, when the rotor is turned, the ribs engage the lugs and turn the top ring, thus troweling the male end of the pipe and especially the groove 40 in that end. It is preferred that the speed of rotation be relatively slow and the rotation unidirect-ional for only a few revolutions, depending upon the diameter of the pipe being cast.
Rotation of the rotor is accomplished in a novel manner as follows: The periphery of the rotor has affixed thereto, as by welding a circular band 50 to which is secured a link or roller 30 chain 52 (broken lines in Fig. 3; full lines in Figs. 5, 6, and 7), the length or circumference of the band 50 so that the chain fits the band with little if any play. The chain is secured to the band by a plurality of wings 54 welded to the chain links at selected intervals, and these wings are in turn secured to the band, as by any type of fastener, such as indicated at 56 (Fig.6). The pressure head has affixed thereto and is surrounded by a depending annular shield 58 which encloses the chain from above and about its circumference. The shield is interrupted at 60 to provide for a supplementary enclosure 62 ~or a driving ~otor 64, which may be air, electrically, etc., driven. As best seen in Fig. 7, the motor carries and drives a relatively small driYer in the form of a sprocket 66 that is in constant mesh with the rotor chain 52. Obviously, the relative sizes of the sprockets will determine the rpm of the motor, and these may be changed according to the type or size of pipe being handled. It is pre-ferred that the rpm be about two-and-one-hal~ revolutions per minute and the amount of rotation be no more than one revolution.
Excess revolutions will erode the stripping medium normally used between the concrete and the inner wall of the jacket.
Fig. 5 shows a further feature of the invention, residing in a hardened-steel or the like internal wear/gap ring 68. Because of the "activity" in this area of the jacket, resulting from ver-tical and angular movement of the top ring, vibration of theconcrete, etc., small but abrasive particles of the mix find their way past the periphery of the top ring and cause premature wear on the interior of the jacket wall. By the interposition of the wear/gap ring, premature wear of the entire jacket is obviated, the wear ring being preferably welded in place.
The initial steps in the operation may follow those well known in the art, at least up to the point at which the top ring is positioned in place and down pressure applied by the pressure head 26. Those skilled in the art are aware of the stage at which pressure, vibration and rotation should occur. As already noted, the down pressureon the pressure head and thus the top ring 20 is effected by the cylinder and piston units 24 and rotation of the top ring is achieved via the motor 64, sprocket 66 and chain 52. At the appropriate time, rotation is halted, the pressure head is raised and the form, together with the cast pipe section, is moved to another area for further handling, such as removal of the form, top and bottom rings and snap ring 34. It is common~
place to manufacture pipe via a process including several stations at which the various steps are carried out. These details form no immediate part of the present invention and hence are not illus-trated and are described except only generally.
~8~
In the Drawings:
Fig. 1 is an elevation, with parts omitted and partly in cross section to better illustrate the construction.
FigO 2 is a plan as seen generally along the line 2-2 of Fig. 1.
Fig. 3 is a bottom view of the rotor for turning the tongue trowel.
Fig. 4 is an enlarged edge view of the chain drive for the rotor.
Fig. 5 is an enlarged fragmentary section showing how the chain is affixed to the rotor.
Fig. 6 is an elevation as seen along the line 6-6 of Fig. 5.
Fig. 7 is a fragmentar~ view showing the motor~sprocket-chain drive for the rotor.
Fig. 8 is an enlarged fragmentary sectional view showing the header ring and its groove-forming ring.
Fig. 9 is a reduced plan of the snap ring ~or the top header ring.
In Fig. l, the numeral 10 designates a floor or e~uivalent support on which a casting mold or form unit 12 is supported, being carried by its lower end. The form here is cylindrical and its long axis is vertical. As i5 typical, the form includes an inner core (not shown) surrounded by a steel jacket 14 having its upper end encircled and reinforced by a steel band 16. The an-nular space between the core and the jacket receives flowable con-crete to form a section of pipe 18. ~ top or upper header ring 20 is placed on top of the upper end of the as-yet unset concrete and this ring is shaped so as to give the upper end of the pipe a somewhat annular tapered form of reduced diameter as respects the basic diameter of the pipe. As is known in the art, this end is the male end and fits into the female end of a neighboring pipe section when the pipe is laid. The lower end of the pipe section appearing here is formed as a bell or female end, the formation following known design and processes.
The form is embraced from above by processing structure in-cluding a pair of upright guide members 22 which are mounted on the floor, rising at diametrically opposite sides of the form.
Each guide member slidably carries an upright slide 24 and these slides are rigidly cross-connected by a transverse member spaced above the form. A pressure head 26 of generally circular con-figuration is interposed horizontally between the cross member 24 and the top of the form and is connected to a plurality o~
hydraulic or air cylinder and piston units 28, the connections being effected as at 30 (Fig. 2). The cylinders of these units are carried by the cross member 24 and retraction and extension of the pistons causes raising and lowering of the pressure head.
The pressure head applies down pressure to the top header ring 20 and holds the ring in place during settling, etc., of the con-crete, conventionally accomplished by vibrators or the like (not shown~. Diametrically opposed portions of the pressure head are controlled or guided by projections 32 cooperating with the slides 24 to maintain the attitude of the pressure head during its ver-tical movement.
As best shown in Figs. 8 and 9, the top ring 20 carries aninternal groove-forming ring 34, having a radial split at 36 and detachably secured within the top ring by a plurality of recessed bi8 cap screws 38 via holes 39 in the ring 34 and tapped bores in the ring 20. The purpose of this ring is to form an annular groove in the top or male end of the pipe, as at 40 in Fig. 8. ~s will be understood from this Figure, the ring 34 is released from the header ring by removal of the cap screws, leaving the snap ring in place in the pipe groove as the top ring is removed upwardly.
Because of the split at 36, the ring 34 can be easily removed from the groove after the concrete has set, etc.
It is a feature of the invention that the top ring may be rotated about the axis of the pipe section during the forming of the section. For this purpose, there is journaled in and below the pressure head, by a central bearing 42 of any suitable nature, a circular rotor 44. This rotor has, rigid on its under side, a plurality of radially elongated driving ribs 46 (Fig. 3). The top ring 20 has a like plurality of upstanding lugs 48 rigid thereon. In the present case, there are three lugs and three ribs. The purpose of the elongated ribs is to enable the rotor to accommodate rop rings of different diameters, it being clear that smaller rings will have their lugs on a smaller circle than larger top rings. This improves the versatility of the apparatus.
Clearly, when the rotor is turned, the ribs engage the lugs and turn the top ring, thus troweling the male end of the pipe and especially the groove 40 in that end. It is preferred that the speed of rotation be relatively slow and the rotation unidirect-ional for only a few revolutions, depending upon the diameter of the pipe being cast.
Rotation of the rotor is accomplished in a novel manner as follows: The periphery of the rotor has affixed thereto, as by welding a circular band 50 to which is secured a link or roller 30 chain 52 (broken lines in Fig. 3; full lines in Figs. 5, 6, and 7), the length or circumference of the band 50 so that the chain fits the band with little if any play. The chain is secured to the band by a plurality of wings 54 welded to the chain links at selected intervals, and these wings are in turn secured to the band, as by any type of fastener, such as indicated at 56 (Fig.6). The pressure head has affixed thereto and is surrounded by a depending annular shield 58 which encloses the chain from above and about its circumference. The shield is interrupted at 60 to provide for a supplementary enclosure 62 ~or a driving ~otor 64, which may be air, electrically, etc., driven. As best seen in Fig. 7, the motor carries and drives a relatively small driYer in the form of a sprocket 66 that is in constant mesh with the rotor chain 52. Obviously, the relative sizes of the sprockets will determine the rpm of the motor, and these may be changed according to the type or size of pipe being handled. It is pre-ferred that the rpm be about two-and-one-hal~ revolutions per minute and the amount of rotation be no more than one revolution.
Excess revolutions will erode the stripping medium normally used between the concrete and the inner wall of the jacket.
Fig. 5 shows a further feature of the invention, residing in a hardened-steel or the like internal wear/gap ring 68. Because of the "activity" in this area of the jacket, resulting from ver-tical and angular movement of the top ring, vibration of theconcrete, etc., small but abrasive particles of the mix find their way past the periphery of the top ring and cause premature wear on the interior of the jacket wall. By the interposition of the wear/gap ring, premature wear of the entire jacket is obviated, the wear ring being preferably welded in place.
The initial steps in the operation may follow those well known in the art, at least up to the point at which the top ring is positioned in place and down pressure applied by the pressure head 26. Those skilled in the art are aware of the stage at which pressure, vibration and rotation should occur. As already noted, the down pressureon the pressure head and thus the top ring 20 is effected by the cylinder and piston units 24 and rotation of the top ring is achieved via the motor 64, sprocket 66 and chain 52. At the appropriate time, rotation is halted, the pressure head is raised and the form, together with the cast pipe section, is moved to another area for further handling, such as removal of the form, top and bottom rings and snap ring 34. It is common~
place to manufacture pipe via a process including several stations at which the various steps are carried out. These details form no immediate part of the present invention and hence are not illus-trated and are described except only generally.
Claims (6)
PRIVILEGE IS CLAIMED ARE DEFINED
1. In apparatus for the manufacture of cast concrete pipe, including support means, a cylindrical core and surrounding an-nular jacket supported at their lower ends in upright fashion by the support means and providing an annular, closed-bottom space having an open upper end, means for filling said space via said open upper end with fluid concrete, an annular header resting on the concrete from above and substantially closing said upper end, said header being both vertically and angularly movable relative to the core, jacket and concrete, pressure head means disposed above the header and movable selectively downwardly to engage and apply pressure to the header and concrete or upwardly away from the jacket, core, header and concrete, said header further having an annular interior shape for effectiving a predetermined annular configuration at the upper end of the pipe being formed, rotor means carried by an under portion of the pressure head for verti-cal movement therewith and for uni-directional rotation relative thereto about the axis-extended of the jacket, header and core, force- transmitting means on the rotor and engageable with the header upon downward movement of the pressure head for turning the header and for upward disengagement from the header upon up-ward movement of the pressure head, and drive means for turning the rotor.
2. In apparatus as defined in Claim 1, the further improve-ment in which the drive means includes driving means carried by the pressure head and driven means carried by the rotor and drivingly engaged with the driven means.
3. In apparatus as in Claim 2, the further improvement in which the rotor is a circular member formed about the rotor axis, the driven means includes tooth elements spaced uniformly angu-larly about the periphery of said member, and the driving means includes a rotatable member having tooth means meshing with the tooth means of the rotor.
4. In apparatus as in Claim 3, the further improvement in which the tooth means on the rotor is an endless link chain affixed to the rotor and the rotatable member of the driving means is a sprocket meshing with the chain.
5. In apparatus as defined in Claim 1, the further improve-ment in which the rotor is a circular member of smaller diameter than the pressure head, the periphery of the rotor has tooth elements thereon, the drive means includes a power-operated device carried by the pressure head at a peripheral portion thereof radially outwardly of the periphery of the rotor and includes a rotatable toothed member with the rotor tooth elements.
6. In apparatus as in Claim 1, the further improvement in which the header has an external annular lip disposed at a level below the upper marginal edge of the jacket wall and closely spaced about its periphery from the interior annular surface of the jacket wall, and an annular wear member is affixed to the interior of the jacket wall at the level of said annular lip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000401505A CA1180168A (en) | 1982-04-22 | 1982-04-22 | Apparatus for forming an annular groove in the end of cast concrete pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000401505A CA1180168A (en) | 1982-04-22 | 1982-04-22 | Apparatus for forming an annular groove in the end of cast concrete pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1180168A true CA1180168A (en) | 1985-01-02 |
Family
ID=4122636
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000401505A Expired CA1180168A (en) | 1982-04-22 | 1982-04-22 | Apparatus for forming an annular groove in the end of cast concrete pipe |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1180168A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104175397A (en) * | 2013-05-22 | 2014-12-03 | 苏州千瑞机电科技有限公司 | Multifunctional fume duct production machine |
-
1982
- 1982-04-22 CA CA000401505A patent/CA1180168A/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104175397A (en) * | 2013-05-22 | 2014-12-03 | 苏州千瑞机电科技有限公司 | Multifunctional fume duct production machine |
| CN104175397B (en) * | 2013-05-22 | 2017-03-22 | 苏州千瑞机电科技有限公司 | Multifunctional fume duct production machine |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEC | Expiry (correction) | ||
| MKEX | Expiry |