权利要求：
Claims
1. A dart flight stem comprising a first portion and a
second portion, wherein the first portion is formed from
a first material and the second portion is moulded or
3D-printed from a second material different from the
first material.
2 A dart flight stem according to Claim 1, wherein the
first portion is moulded or 3D-printed from the first
material.
3. A dart flight stem according to Claim 1 or 2, wherein
the first portion and the second portion are integrally
formed as a unitary body.
4, A dart flight stem according to Claim 1, 2 or 3, wherein
the first material and the second material are co-
moulded.
8. A dart flight stem according to any preceding claim,
wherein the second portion includes a plurality of
second portions formed on the outside of the first
portion.
6. A dart flight stem according to any preceding claim,
wherein the first portion is formed as a core and the
second material is moulded onto and/or around the core
of first material to form the second portion.
1. A dart flight stem according to Claim 1 or 2, wherein
the first portion is formed as a core and the second
portion is formed as two or more mating pieces that form
a casing around the core, optionally wherein the mating
pieces are opposed halves that extend around both sides
of the core either to matingly engage one another or to
matingly engage the first portion.
8. A dart flight stem according to Claim 6 or 7, wherein
the core includes one or more projections extending
radially from a substantially cylindrical or prismatic
elongate central body, and wherein the second portion
substantially covers and/or surrounds the central body
but not the one or more projections such that they are
exposed at least at their radially outer surfaces.
9. A dart flight stem according to Claim 8, wherein the one
or more projections includes at least two projections,
and wherein the at least two projections extend from the
elongate central body in different radial directions,
optionally wherein the radial directions are
substantially 60 degrees, 90 degrees, 120 degrees or 180
degrees apart with respect to a longitudinal axis of the
central body.
10. A dart flight stem according to Claim 8 or 9, wherein at
least one of the one or more projections is formed with
a faceted or grooved outer surface.
11. A dart flight stem according to any preceding claim,
wherein one of the first and second portions 1s
substantially transparent or translucent and the other
of the first and second portions is substantially
opaque.
12. A dart flight stem according to any preceding claim,
wherein one of the first and second materials is
relatively resilient and the other of the first and
second materials is relatively brittle.
13. A dart flight stem according to Claim 12, wherein the
portion of relatively resilient material reinforces the
portion of relatively brittle material.
14. A dart flight stem according to any preceding claim,
wherein the flight stem includes an elongate body having
a front end with a threaded connection portion and a
back end with petals projecting rearwardly from bases
thereof.
15. A dart flight stem according to Claim 14, wherein a
region of the flight stem immediately adjacent the
threaded connection portion and/or a region immediately
at and adjacent the base of each of the petals is formed
from the second material.
16. A dart flight stem according to Claim 15, wherein the
threaded connection portion, the petals, the immediately
adjacent portions of the elongate body, and a portion of
the elongate body extending therebetween are integrally
formed from the second material.
17. A dart flight stem according to Claim 15 or 16 as
dependent directly or indirectly from Claim 12, wherein
the second material is relatively resilient and the
first material is relatively brittle.
18. A dart flight stem according to any preceding claim,
wherein the first material is a translucent plastic,
which may be polycarbonate, and the second material is
an opaque polymer, which may be nylon.
19. A dart flight stem according to any preceding claim,
wherein the first material and the second material have
substantially the same chemical composition but at least
one of the first and second materials includes an
additive so that it is a different colour and/or opacity
from the first material.
20. A dart flight stem comprising a specular component
arranged to reflect light arriving from a predominantly
radial direction with respect to a longitudinal axis of
the flight stem towards a back end of the flight stem.
21. A darft flight stem according to Claim 20, wherein the
specular component is arranged to reflect substantially
all light in the visible spectrum.
22. A dart flight stem according to Claim 20 or 21, wherein
the dart flight stem is a dart flight stem according to
any one of Claims 1 to 19 and the specular component is,
or 1s formed by, the first or second portion.
23. A method of manufacturing a dart flight stem comprising:
providing a first portion of the flight stem made
from a first material in a stem mould; and
moulding a second portion of the flight stem from a
second material in the stem mould together with the
first portion.
24. A method of manufacturing a dart flight stem according
to Claim 23, wherein moulding the second portion
includes injection moulding the second portion by
injecting the second material into the stem mould.
25. A method of manufacturing a dart flight stem according
to Claim 23 or 24, wherein providing the first portion
includes moulding the first portion in a first portion
mould or 3D-printing the first portion with a 3D-
printer.
26. A method of manufacturing a dart flight stem according
to Claim 23, 24 or 25, wherein providing the first
portion includes placing the first portion in the stem
mould in an open configuration of the stem mould and
closing the stem mould such that the first portion is
securely held in place inside the stem mould in a closed
configuration of the stem mould.
27. A method of manufacturing a dart flight stem according
to any one of Claims 23 to 26, wherein the first portion
includes two or more projections that are contacted by
the stem mould in the closed configuration to hold the
first portion in place.
28. A method of manufacturing a dart flight stem according
to any one of Claims 23 to 27, wherein the stem mould
secures the first portion on opposite sides of the first
portion to inhibit lateral motion of the first portion
during moulding of the second portion.
29. A method of manufacturing a dart flight stem according
to Claim 28, wherein the stem mould includes clamp parts
for securing the first portion on opposite sides, and
wherein the clamp parts define windows in the sides of
the moulded second portion.
30. A method of manufacturing a dart flight stem according
to any one of Claim 28 or 29, wherein the lateral motion
is inhibited in a direction substantially orthogonal to
a direction in which a or the projections of the first
portion project.
31. A method of manufacturing a dart flight stem according
to any one of Claims 23 to 30, wherein moulding the
second portion includes injecting the second material
into the stem mould onto and/or around the first portion
to form the second portion.
32. A method of manufacturing a dart flight stem according
to any one of Claims 27 to 30, or Claim 31 as dependent
directly or indirectly on Claim 27, wherein moulding the
second portion includes substantially covering and
surrounding the first portion with the second material
injected into the stem mould, with the exception of the
projections that are contacted by the mould, such that
the projections are uncovered by the second material at
least at their radially outer surfaces.
33. A method of manufacturing a dart flight stem according
to any one of Claims 23 to 32, wherein the dart flight
stem is a dart flight stem according to any one of
Claims 1 to 22.
34. A method of manufacturing a dart flight stem comprising:
providing a first component made from a first
material and including a core portion; and
encasing the core portion within a second component
made from a second material, the second component being
formed from two or more parts by placing the parts
around the core and mating the two or more parts with
one another and/or with the first component.
35. The method of Claim 35, wherein the two or more parts
includes two halves that are arranged to matingly engage
with an interference fit, and the method includes
positioning the two halves on opposite sides of the core
and bringing the two halves into mating engagement with
one another with the core between them.