U.S. patent application number 11/312582 was filed with the patent office on 2006-08-17 for abutment joint for paper reel cores.
This patent application is currently assigned to Oy Core Handling Ltd.. Invention is credited to Pekka Amto.
Application Number | 20060180701 11/312582 |
Document ID | / |
Family ID | 33547915 |
Filed Date | 2006-08-17 |
United States Patent
Application |
20060180701 |
Kind Code |
A1 |
Amto; Pekka |
August 17, 2006 |
Abutment joint for paper reel cores
Abstract
An abutment joint for end-to-end joining of paper reel cores,
the abutment joint comprising a first conical surface (4) formed on
the outer surface of one core (2) and a second conical surface (3)
formed on the inner surface of the other core (1), whereby said
first conical surface and said second conical surface abut against
each other in the joint, wherein at least one protrusion (6) is
formed at least on one conical surface and at least one groove (5)
is formed at least on the other conical surface to form an
interlocking joint between the cores.
Inventors: |
Amto; Pekka; (Hamina,
FI) |
Correspondence
Address: |
BUCHANAN INGERSOLL PC;(INCLUDING BURNS, DOANE, SWECKER & MATHIS)
POST OFFICE BOX 1404
ALEXANDRIA
VA
22313-1404
US
|
Assignee: |
Oy Core Handling Ltd.
Lappeenranta
FI
|
Family ID: |
33547915 |
Appl. No.: |
11/312582 |
Filed: |
December 21, 2005 |
Current U.S.
Class: |
242/605 ;
242/609 |
Current CPC
Class: |
B65H 75/50 20130101 |
Class at
Publication: |
242/605 ;
242/609 |
International
Class: |
B65H 75/18 20060101
B65H075/18 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 29, 2004 |
FI |
U20040490 |
Claims
1. An abutment joint for end-to-end joining of paper reel cores,
the abutment joint comprising a first conical surface (4) formed on
the outer surface of one core (2) and a second conical surface (3)
formed on the inner surface of the other core (1), whereby said
first conical surface and said second conical surface abut against
each other in the joint, at least one protrusion (6) is formed at
least on one conical surface, and at least one groove (5) is formed
at least on the other conical surface to form an interlocking joint
between the cores.
2. The abutment joint according to claim 1, wherein the protrusion
(6) is formed on the conical surface (4) formed on the outer
surface of the core (2) and the groove (5) is formed on the conical
surface (3) formed on the inner surface of the core (1).
3. The abutment joint according to claim 1, wherein the protrusion
(6) is formed to the end of the core.
4. The abutment joint according to claim 1, wherein glue is applied
on the conical surface (3, 4) of at least one of the cores.
5. The abutment joint according to claim 2, wherein the protrusion
(6) is formed to the end of the core.
6. The abutment joint according to claim 2, wherein glue is applied
on the conical surface (3, 4) of at least one of the cores.
7. The abutment joint according to claim 3, wherein glue is applied
on the conical surface (3, 4) of at least one of the cores.
8. The abutment joint according to claim 5, wherein glue is applied
on the conical surface (3, 4) of at least one of the cores.
Description
[0001] The invention relates to end-to-end joining of paper reel
cores. In more detail the invention relates to a shape of the joint
used in said joining.
[0002] In paper industry, a paper web is conventionally wound up
during different finishing operations on a core made from a
plurality of spirally overlappingly wound plies of narrow strips of
board. Prior to their winding into a core, the board strips are
glued, conventionally using a sodium silicate solution. The
finished core length must be exactly matched with the width of the
paper web exiting from a slitter and being wound on the core.
Furthermore, the core must be flawless to avoid problems in
co-operation of the reels with the spindles of winder equipment
employed in the final use and/or finishing of the paper.
[0003] A used core presents a waste problem, since only a part of
such used cores can be reused for manufacturing core board.
Consequently, while effort has been made to find possibilities of
recycling cores, also this approach involves problems. The most
essential problem is the damage caused to the core ends.
Conventionally, methods of overcoming this drawback have been
sought from reworking of core sections. A basic goal of reworking
is to remove the damaged portion from the core end and then to join
the thus reworked core end with the end of another core section
similarly reworked so as to form a continuous core master that can
be severed to desired lengths for reuse. One type of joining method
and apparatus of this kind has been described in the international
publication WO 00/03868.
[0004] In the known solutions, conical surfaces are first made on
the surfaces of the cores to be joined so that on one core a
conical surface is formed on the inner surface of the core and on
the other core a conical surface is formed on the outer surface of
the core. Glue is then applied either to the conic surface of one
core or both cores, and the cores are then pushed end to end so
that the formed conical surfaces abut against each other. This is
repeated to form a continuous core master from pieces which core
master is severed to cores of desired lengths for reuse.
[0005] In the above described method and apparatus for joining
cores, the glue to be used must be fast drying in order immediately
to obtain a sufficiently strong joint for the cores to be joined
using continuously operating joining equipments.
[0006] It is not possible to obtain a sufficiently fast drying glue
without sacrificing its other properties. Furthermore, in using
such a fast-drying glue, reaction time of glue on the surface of
the core will be relatively short impairing the quality and
stability of the joint.
[0007] In the present invention, on working the conical surfaces of
the cores to be joined, a protrusion is formed at the nose of one
conic surface, and a complementary groove is formed at the roof of
the other conical surface, whereby, after adding glue, said
protrusion and said groove form an interlocking (form-fit) joint
between the cores,. This interlocking joint supports the joint
directly after joining the mating surfaces enabling so the use of
glues drying more slowly and having improved reactivity with the
mating surfaces. This enables to obtain a longitudinal joint of
improved stability and improved quality.
[0008] More specifically the longitudinal end-to-end joint of cores
according to the invention is characterized in what is defined in
the characterizing part of claim 1.
[0009] The invention will next be described in more detail with
reference to the appended drawing in which
[0010] FIG. 1 shows an embodiment of joining surfaces formed
according to the invention.
[0011] In the embodiment of in FIG. 1 the cores to be joined are
shown in cross section. A conical surface 3 is formed on the inner
surface of the core 1 and a conical surface 4 is formed on the
outer surface of the core 2, by means of which conical surfaces the
cores are joined in an abutting manner against each other. A
protrusion 6 is formed on the conical surface 4 at the nose of the
core 2, the protrusion 6 projecting from the conical surface
approx. 2-3 mm. The length of the protrusion from the core end is
approx. 5 mm. Correspondingly, a groove 5 complementary to said
protrusion of the core 2, is formed at the inner edge of the
conical surface 3 of the core 1.
[0012] When the cores 1 and 2 of FIG. 1 are joined to each other,
glue is first applied to one of the conical surfaces or to both
conical surfaces 3 and 4. Then, the conical surface 4 of the core 2
is pushed into the core 1 so that the conical surfaces will abut
against each other. When the cores are pushed together, the end
edge of the core 2 will flex to enable the protrusion 6 to be
inserted into the groove 5 and thus to form an interlocking joint
between the core 1 and the core 2. This interlocking joint supports
the formed core joint thus giving the glue more time to dry and to
form a stable and good-quality glue joint between the cores.
[0013] In the solution according to the invention, the protrusion
may be formed at any site of either of the surfaces of the cores to
be joined. Preferably it is, however, formed adjacent to the end
edge of the core to enable the protrusion to flex inwardly while
being inserted into the complementary groove. If required, it is
also possible to form a protrusion on both conical surfaces of the
cores to be joined and complementary grooves on the opposite
conical surface.
* * * * *