Field of the Invention
[0001] The present invention relates to a sight used as an archery equipment (hereinafter
referred to as a "sight").
Related Background Art
[0002] As shown in Fig. 1, a bow 1 for use in archery is composed of a bow portion 1 and
a string 2. The bow portion 1 is an arcuate plate-like member, to the ends of which
the ends of the string 2 are respectively attached. When the string 2 is drawn, the
distance between the ends of the bow portion 1 is reduced, and the bow rim is deflected.
The deflection of the bow portion 1 causes elastic energy for shooting out an arrow
to be accumulated in the bow portion 1. The string 2 transmits the elastic energy
accumulated in the bow portion 1 to the arrow.
[0003] Further, a stabilizer 3 and a sight 4 are mounted to the bow portion 1 so as to extend
forwards from the bow portion 1 respectively. The stabilizer 3 is mounted for the
purpose of stabilizing the attitude of the bow and mitigating vibration, impact, etc.
The sight 4 is mounted for the purpose of aiming the arrow to the target.
[0004] The sight 4 is a device which relates the line of sight of an athlete, the attitude
of the bow portion 1 held by the athlete, and the target P. As shown in Figs. 2A and
2B, the sight 4 has an elevation bar 11, a box 12, and a sight pin 6. The elevation
bar 11 is fixed by means of a mounting shaft 5 extending forwards from the bow portion
1 such that the elevation bar 11 is positioned substantially along the vertical direction
when shooting is performed with the bow portion 1 upright.
[0005] The box 12 is mounted to the elevation bar 11 so as to be slidable along the elevation
bar 11. Arranged on the elevation bar 11 is a feed screw 13 elongated in the axial
direction of the elevation bar 11. The feed screw 13 is threadedly engaged with the
box 12 so that the box 12 can make fine movement along the elevation bar 11 through
rotation of the feed screw 13.
[0006] The sight pin 6 is mounted to the box 12. The sight pin 6 is formed as a thin and
narrow cylinder with a small circular section, and is mounted to the box 12 such that
the axis of the pin is substantially aligned with the line connecting the eyes of
the athlete and the target P when shooting is performed with the bow portion 1 upright.
As shown in Fig. 1, in this condition, the athlete firmly holds the bow portion 1
such that the small circular section of the sight pin 6 is aimed at the target P,
whereby it is always possible for the athlete to hold the bow portion 1 in the same
condition.
[0007] In reality, however, the bow portion 1 cannot always be held perfectly in the same
condition in the strict sense. Further, even if the bow portion 1 is held perfectly
in the same condition in the strict sense, it can happen that, when the athlete shoots
with the sight pin 6 of the sight 4 aimed at the target P, the arrow is off the mark
depending upon the physical condition of the athlete, the weather, etc. In such cases,
the box 12 is moved along the elevation bar 11 in accordance with the deviation amount
to shift the position of the sight pin 6 and correct the previous shooting condition
of the athlete. The athlete senses a difference between the shooting the target P
with the sight pin 6 at the initial position and the shooting the target P with the
position of the sight pin 6 shifted, and thereby can refer to it as information for
correction for the next shooting.
[0008] In this way, the sight 4, which is a device used as a reference for the athlete when
performing shooting next, is required to always exhibit highly accurate positional
reproducibility. In particular, due to vibration or the like caused by the deformation
of the bow portion 1, the box 12 is likely to be displaced with respect to the elevation
bar 11. However, in the conventional sight 4, in which the box 12 is caused to slide
along the elevation bar 11, it is necessary to perform dimensional processing on the
box 12 and the elevation bar 11, with a gap for processing being maintained between
the box 12 and the elevator bar 11. Further, in this processing, a dimensional tolerance
is naturally required. As a result, between the box 12 and the elevation bar 11, in
each dimension, there exists a gap caused by a tolerance required. This gap leads
to rattling of the box 12 with respect to the elevation bar 11, and by extension,
to a positional error of the box 12 with respect to the elevation bar 11. Such rattling
is generated in both the horizontal and the vertical directions of the sections of
the box 12 and the elevation bar 11. That is, though needed in terms of processing,
this gap leads to rather poor reproduction performance for an archery-sight, resulting
in rather poor usability for the athlete.
SUMMARY OF THE INVENTION
[0009] The purpose of the invention is provided to solve the above-mentioned problems.
[0010] Another purpose of the invention is to provide an archery sight mounted to a bow
portion for archery, including: an elevation bar fixed to the bow portion and having
a first sliding surface and a second sliding surface; a box mounted so as to be slidable
along the first sliding surface and the second sliding surface of the elevation bar;
an elastic member mounted to the box so as to be opposed to the first sliding surface;
and a pressurizing means that pressurizes the elastic member in a direction at an
angle with respect to the first sliding surface to deform the elastic member, the
box being pressurized by the first sliding surface due to the elastic member and pressed
against the second sliding surface.
[0011] Due to the above construction, it is possible to move the box while involving no
play between itself and the elevation bar, with load being applied to the elevation
bar.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012]
Fig. 1 is a general view of an archery bow;
Fig. 2A is a side view of an archery-sight according to the present invention;
Fig. 2B is a front view of the archery-sight according to the present invention;
Fig. 3 is a sectional view of a sight according to a first embodiment of the present
invention, mainly showing the box and the elevation bar thereof;
Fig. 4 is a schematic view of the sight according to the first embodiment of the present
invention, showing the relationship between a first sliding surface, a pressure screw,
and a pressure plate;
Fig. 5 is a sectional view of the sight according to the first embodiment of the present
invention, showing in detail the load directions in the portion where the box and
the elevation bar exist;
Fig. 6 is a diagram showing an example of a sight according to a second embodiment
of the present invention; and
Fig. 7 is a diagram showing another example of the sight according to the second embodiment
of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(Embodiment 1)
[0013] The embodiment 1 of the present invention will be described with reference to Figs.
1 through 4.
[0014] As shown in Fig. 1, the archery bow 1 has the bow portion 1 and the string 2. The
operations of the bow portion 1 and the string 2 are as described above. The stabilizer
3 and the sight 4 are further mounted to the bow portion 1 so as to extend forwards
from the bow portion 1. The operations of the stabilizer 3 and the sight 4 are also
as described above. As shown in Figs. 2A and 2B, the sight 4 includes an elevation
bar 11, an box 12, and a sight pin 6. The elevation bar 11 is fixed with regard to
the bow portion 1 by means of the extension 5 extending forwards so as to be substantially
in the vertical position when a person shoots a bow with vertically positioning the
bow portion 1.
[0015] As shown in Figs. 2A and 2B, the box 12 is mounted to the elevation bar 11 so as
to be capable of sliding along the elevation bar 11. Arranged on the elevation bar
11 is the feed screw 13 elongated in the axial direction of the elevation bar 11.
The feed screw 13 is threadedly engaged with the box 12, enabling the box 12 to make
fine movement along the elevation bar 11 through rotation of the feed screw 13. The
sight pin 6 is mounted to the box 12. The function of the sight pin 6 is also the
same as described above.
[0016] Subsequently, the portions featuring the present invention will be described with
reference to Figs. 2A, 2B, and 3 through 5. Fig. 3 is a sectional view taken along
the line 3-3 of Fig. 2A.
[0017] The box 12 has is mounted to the elevation bar 11 so as to be slidable along the
same. For example, the box 12 has a sectional configuration enclosing the elevation
bar 11.
[0018] At the center of the elevation bar 11, there is arranged the feed screw 13 so as
to extend in the sliding direction of the box 12, which corresponds to the longitudinal
direction of the elevation bar 11. Preferably, the feed screw 13 is arranged substantially
at the center of the elevation bar 11.
[0019] The elevation bar 11 has a first sliding surface 20 and a fourth sliding surface
23 provided with an angle with respect to the first sliding surface. For example,
the first and fourth sliding surfaces on the box 12 are provided on the main body
side of the elevation bar 11. Respectively mounted to the portions of the box 12 corresponding
to the first sliding surface 20 and the fourth sliding surface 23 are pressure plates
14 and 15, which are elastic members. The pressure plates 14 and 15 are formed of
an elastic resin, typical examples of which include polyamide resin and polyacetal
resin.
[0020] The pressure plates 14 and 15 are respectively arranged so as to be opposed to the
first and fourth sliding surfaces 20 and 23, which means each of them has substantially
the same angle as the first and fourth sliding surfaces 20 and 23.
[0021] Each of the pressure plates 14 and 15 is mounted to the box 12, with their both ends
being fixed thereto. The box 12 is equipped with holes having screw portions each
at an angle with respect to the pressure plates 14 and 15. Presser screws 30 and 31
as pressurizing means are respectively threadedly engaged with the holes having the
screw holes. A plurality of holes having screw portions are arranged in the longitudinal
direction of each of the pressure plates 14 and 15. Further, plural screws are threadedly
engaged so as to be respectively in correspondence with the holes.
[0022] Fig. 4 shows the positional and operational relationship between the pressure plate
14, the first sliding surface 20, and the plurality of pressure screws 30 and 32 threadedly
engaged with the holes having screw portions formed so as to be at an angle with respect
to the pressure plate 14. While the drawing only shows the relationship between the
pressure plate 14, the first sliding surface 20, and the pressure screws 30 and 32,
the same applies to the relationship between the pressure plate 15, the fourth sliding
surface 23, and the pressure screw 31, which are in plane symmetry therewith.
[0023] As shown in the drawing, the pressure plate 14 has at its ends tab portions 14a and
14b for mounting. The pressure plate 14 is fixed in position such that the tab portions
14a and 14b enter the end portions of the box 12. Thus, the pressure plate 14 is in
a plate-beam-like state with their both ends fixed. Between the tab portions 14a and
14b at the ends of the pressure plate 14, there are arranged the pressure screws 30
and 32 serving as the pressurizing means. Although not shown in Fig. 4, the box 12
has holes having screw portions formed so as to be at an angle with respect to the
pressure plate 14, and the pressure screws 30 and 32 are threadedly engaged with these
holes as described above.
[0024] With the pressure plate 14 being fixed to the box 12 by means of the tab portions
14a and 14b, the lower surface of the pressure plate 14 is adjusted so as to constitute
a surface 14c which is in contact with the first sliding surface 20 while being substantially
parallel thereto. The positions of the end portions of the pressure screws 30 and
32 are adjusted such that, in the initial state, their forward ends abut the upper
surface of the pressure plate 14, which is in contact with the first sliding surface
20. When they are further tightened, the pressure screws 30 and 32 go ahead along
the holes by thread provided in the respective holes, until the forward ends of the
pressure screws 30 and 32 protrude on the other side. The respective protruding forward
ends of the pressure screws 30 and 32 gives pressure to the surface of the pressure
plate 14 and deforms the pressure plate 14 so as to be shifted from the position of
the surface 14c to the first sliding surface 20, which is in contact with the first
sliding surface 20 while being substantially parallel thereto, to a deflected position
14d, where it pressurizes the first sliding surface 20. That is, as a result of the
respective forward end portions of the pressure screws 30 and 32 protruding, the pressure
screws 30 and 32 as pressurizing means pressurizes the surface of the pressure plate
14 as the elastic member against the first sliding surface 20 with deforming the elastic
member.
[0025] Fig. 5 schematically shows the relationship between the elevation bar 11 and the
box 12 of Fig. 3. In the following, the relationship will be described in more detail
with reference to Figs. 3 and 5.
[0026] A second sliding surface 21 is arranged on the elevation bar 11 on the same side
as the first sliding surface 20 as well as on the side opposite to the box 12, and
a fifth sliding surface 24 is arranged on the elevation bar 11 on the same side as
the fourth sliding surface 23 as well as on the side opposite to the box 12.
[0027] On the box 12 side, there are arranged at respective positions opposed to the second
sliding surface 21 and the fifth sliding surface 24, receiving portions 22 and 25
constituting other elastic members. It is desirable for the receiving portions 22
and 25 to be formed of an elastic resin respectively. Typical examples of the resin
include polyamide resin and polyacetal resin.
[0028] In this construction, when the surface of the pressure plate 14 deformed through
pressurization due to the protrusion of the forward end portions of the pressure screws
30 and 32 pressurizes the box 12 through the intermediation of the first sliding surface
20, the box 12 is inclined to move in the pressurizing direction. At the same time,
the forward end portions of the pressure screws 31 and 33 protrude, whereby the pressure
plate 15 is pressurized to be deformed, and the deformed surface of the pressure plate
15 is pressed against the box 12 through the intermediation of the fourth sliding
surface 23. As a result, there is no more clearance (gap) between the first sliding
surface 20 and the pressure plate 14 and between the fourth sliding surface 23 and
the pressure plate 15, respectively.
[0029] The first sliding surface 20 and the fourth sliding surface 23 provided with an angle
to the first sliding surface 20 are respectively arranged on the box. The pressure
plates 14 and 15 fixed thereto are also arranged at an angle, so that, as indicated
by the arrows in Fig. 5, the pressurization by the pressure screws 30 and 31 presses
the box against the sides respectively opposed to the pressure screws 30 and 31, that
is, against the receiving portions 17 and 16, respectively.
[0030] Conversely, when viewed in terms of the horizontal and vertical components of the
pressurization force by the pressure screws 30 and 31, arranged as shown in Fig. 5,
the box 12 is to be pressed against the elevation bar 11 in both the horizontal and
the vertical directions. As a result, due to the pressurization by the pressure screws
30 and 31, the pressure plates 14 and 15 are deformed to pressurize the first sliding
surface 20 and the fourth sliding surface 23, and due to this pressurization exerted
on the first sliding surface 20 and the fourth sliding surface 23, the elevation bar
11 makes a relative movement away from the box 12. Further, as a result, the second
sliding surface 21 and the fifth sliding surface 24, arranged on the elevation bar
11 on the opposite sides of the first sliding surface 20 and the fourth sliding surface
23, are respectively pressurized so as to bring them into contact with the third sliding
surface 22 and the sixth sliding surface 25 of the receiving portion 16. As a result,
there is no more play between the second sliding surface 21 and the third sliding
surface 22. Similarly, there is no more clearance between the fifth sliding surface
24 and the sixth sliding surface 25.
[0031] Pressurization is exerted in the horizontal direction in Fig. 5, with the first sliding
surface 20 and the fourth sliding surface 23 being opposed to each other, so that
the box 12 is fixed to the elevation bar 11 also in the horizontal direction.
[0032] Here, it is desirable for the first sliding surface 20 and the second sliding surface
21 to be parallel to each other. Further, it is also desirable for the fourth sliding
surface 23 and the fifth sliding surface 24 to be parallel to each other. As will
be illustrated with reference, for example, to the relationship between the pressure
screw 30, the pressure plate 14, the first sliding surface 20, and the second sliding
surface 21, of the pressurizing force of the pressure screw 30 causing deformation
of the pressure plate 14, the vertical force component thereof as seen in Fig. 5 is
transmitted to the first sliding surface 20, and at the same time, is transmitted
more efficiently to the second sliding surface 21, which is substantially parallel
to the first sliding surface 20.
[0033] In this way, by the screws serving as the pressurizing means, the box 12 is substantially
fixed to the elevation bar 11, with practically no play left in the horizontal direction
nor the vertical direction in the section thereof. It should be noted, however, that
the pressure plates 14 and 15 and the receiving portions 16 and 17 are formed of elastic
chemical resin, so that, even in the state in which the pressure plates 14 and 15
are deformed by the pressure screws 30, 31, 32, and 33 respectively serving as the
pressurizing means and pressed against the first sliding surface 20, that is, even
in the state in which fixation is substantially effected with practically no play
in the horizontal direction nor the vertical direction, the box 12 can slide in the
axial direction, which is the longitudinal direction of the elevation bar 11, along
the first sliding surface 20 while involving no play.
[0034] That is, although due to the pressure plates 14 and 15 and the receiving portions
16 and 17 there is no gap between the box 12 and the elevation bar 11, and the box
12 is fixed in both the horizontal direction and the vertical direction in the section
of the box 12 and the elevation bar 11, the box 12 can slide along the elevation bar
11. This helps to enhance the positional reproducibility of the sight pin 6 mounted
to the box 12 with respect to the elevation bar 11.
[0035] It should be noted that, through adjustment of the amount by which the pressure screws
30 and 32 protrude, it is possible to adjust the force with which the pressure plate
14 pressurizes the first sliding surface 20. This makes it possible to adjust the
frictional force between the pressure plate 14 and the first sliding surface 20, making
it possible to adjust the manner in which the box 12 moves relative to the elevation
bar 11. This also applies to the relationship between the pressure screws 31 and 33
and the pressure plate 15.
(Second Embodiment)
[0036] As described in the first embodiment, according to the present invention, there are
mounted the pressure plates 14 and 15 consisting of elastic members at the portions
of the box 12 respectively corresponding to the two surfaces; the first sliding surface
20 and the fourth sliding surface 23 arranged at an angle with respect to the first
sliding surface 20, whereby the box 12 can move along the elevation bar 11 while fixed
in both the horizontal direction and the vertical direction.
[0037] However, as shown in Fig. 6 or 7, the same effect can also be achieved with a single
set of components consisting of the first sliding surface 20, the pressure plate 14,
and the pressure screw 30. In this case, the second sliding surface 21 is arranged
on the surface of the elevation bar facing in the pressurizing direction of the pressure
screw 30, opposed to the box 12 on the opposite side of the first sliding surface
20. And, the third sliding surface 22 is arranged on the portion of the box 12 corresponding
to the second sliding surface 21. The third sliding surface 22 is formed of elastic
resin. In this case, as shown in Fig. 6, a groove is provided in the box 12, with
the third sliding surface 22 constituting a part of this groove. On the other hand,
the elevation bar 11 has a protrusion with a sectional configuration corresponding
to this groove, with the second sliding surface 21 constituting a part of this protrusion.
Thus, even when the groove and the protrusion are engaged with each other and pressurization
is effected from one direction, the effect is the same as that when fixation is effected
in both the horizontal direction and the vertical direction in Fig. 6, with the box
12 being enabled to move along the elevation bar 11.
[0038] Further, while in the example shown in Fig. 6 the box 12 has a groove and the elevation
bar 11 has a protrusion with a sectional configuration corresponding to the groove,
this relationship may be reversed, as shown in Fig. 7.
[0039] That is, in the case of Fig. 7, the box 12 is equipped with a protrusion, and the
third sliding surface 22 constitutes a part of this protrusion. On the other hand,
the elevation bar 11 has a groove with a sectional configuration corresponding to
this protrusion, with the second sliding surface 21 constituting a part of this groove.
Thus, even when the groove and the protrusion are engaged with each other, and pressurization
is effected from one direction, the same effect as that in the case of Fig. 6 is obtained.
1. A sight used by mounting on a bow portion for archery, comprising:
an elevation bar fixed with respect to the bow portion and having a first sliding
surface and a second sliding surface which is an opposite side surface to the first
sliding surface;
a box having a third sliding surface opposed to the second surface, slidably provided
along said elevation bar;
an elastic member provided being to be opposed to the first sliding surface; and
pressurizing means that pressurizes said elastic member against the first sliding
surface with deforming the elastic member, whereby the second sliding surface of the
box is pressurized against the third sliding surface and said box is still slidable
along said elevation bar in a state there is no clearance.
2. A sight according to claim 1, wherein the pressurizing means is a screw mounted to
the box, and wherein the box has a screw portion to be threadedly engaged with the
screw, threaded engagement of the screw with the screw portion results in the screw
deforming the elastic member and pressurizing the elastic member against the first
sliding surface.
3. A sight according to claim 1, wherein both ends of the elastic member are fixed to
the box, and wherein a plurality of the pressurizing means is a plurality of screws
provided between the both ends along the first sliding surface and mounted to the
box, and wherein the box has screw portions, each of which is threadedly engaged with
each of the screws, whereby threaded engagement of the screws with the screw portions
results in the screw deforming the elastic member and pressurizing the elastic member
against the first sliding surface.
4. A sight according to any one of claims 1 to 3, wherein the elastic member is formed
of a resin.
5. A sight according to claim 4, wherein one of said box and said elevation bar has a
groove extending along the first sliding surface, the second sliding surface being
a surface of and wherein the other of said box and said elevation bar has a protrusion
capable of being received in the groove.
6. A sight according to claim 5, wherein the second sliding surface is a surface of one
of said groove or said protrusion in said box, and the third sliding surface is a
surface of the other of the groove or the protrusion in said elevation bar.
7. A sight used by mounting on a bow portion for archery, comprising:
an elevation bar fixed with respect to the bow portion and having:
a first sliding surface;
a second sliding surface which is an opposite side surface to the first sliding surface;
a fourth sliding surface provided with an angle to the first sliding member;
a fifth sliding surface which is an opposite side surface to the fourth sliding surface;
a box having a third sliding surface opposed to the second surface and a sixth sliding
surface opposed to the fifth surface, slidably provided along said elevation bar;
an elastic member provided to be opposed to the first sliding surface and the fourth
sliding surface; and
pressurizing means that pressurizes said elastic member against the first sliding
surface and the fourth sliding surface with deforming the elastic member, whereby
the second sliding surface and the fifth sliding surface of the box are pressurized
against the third sliding surface and the sixth sliding surface, and said box is still
slidable along said elevation bar in a state there is no clearance.
8. A sight according to claim 7, wherein the pressurizing means is a screw mounted to
the box, and wherein the box has a screw portion to be threadedly engaged with the
screw, threaded engagement of the screw with the screw portion results in the screw
deforming the elastic member and pressurizing the elastic member against the first
sliding surface and the second sliding surface.
9. A sight according to claim 7, wherein both ends of the elastic member are fixed to
the box, and wherein a plurality of the pressurizing means is a plurality of screws
provided between the both ends along the first sliding surface and mounted to the
box, and wherein the box has screw portions, each of which is threadedly engaged with
each of the screws, whereby threaded engagement of the screws with the screw portions
results in the screw deforming the elastic member and pressurizing the elastic member
against the first sliding surface and the fourth sliding surface.
10. A sight according to any one of claims 7 to 9, wherein the elastic member is formed
of a resin.
11. A sight according to claim 10, wherein one of said box and said elevation bar has
a groove extending along the first sliding surface, the second sliding surface being
a surface of and wherein the other of said box and said elevation bar has a protrusion
capable of being received in the groove.
12. A sight according to claim 11, wherein the second sliding surface and the fifth sliding
surface are surfaces of ones of said grooves or said protrusion in said box, and the
third sliding surface the sixth sliding surface are surfaces of the other ones of
the groove or the protrusion in said elevation bar.
13. A method for slidably fixing an elevation bar of a sight used by mounting on a bow
portion for archery, wherein the elevation bar having a first sliding surface and
a second sliding surface which is an opposite side surface to the first sliding surface,
comprising:
a step of inserting a box having a third sliding surface opposed to the second surface;
and
a step of pressurizing an elastic member provided between said box and said elevation
and opposed to the first sliding surface against the first sliding surface with deforming
the elastic member, whereby the second sliding surface of the box is pressurized against
the third sliding surface and said box is still slidable along said elevation bar
in a state there is no clearance.
14. A sight for mounting on a portion of an archery bow, the sight comprising:
an elevation bar, defining an axis, fixed with respect to the bow portion and having
a first sliding surface and a second sliding surface which is an opposite side surface
to the first sliding surface;
a box having a third sliding surface opposed to the second sliding surface, slidably
provided along said elevation bar;
an elastic member opposing the first sliding surface; and
pressurizing means arranged to, in use, pressurize said elastic member against the
first sliding surface by deforming the elastic member, whereby the box is brought
into a clamped condition in which the third sliding surface of the box is pressurized
against the second sliding surface of the elevation bar with substantially no clearance
therebetween and said box is axially slidable along said elevation bar.
15. An archery bow sight, the sight comprising:
a bar defining an axis, the bar having first and second slide surfaces,
a sight element comprising a deformable element and a contact surface,
the sight element being slidably mounted on the bar, such that a surface of the deformable
element opposes the first slide surface and the contact surface opposes the second
slide surface,
the sight element further comprising means for deforming the deformable element into
a clamping condition in which the deformable element surface abuts the first slide
surface, wherein in said clamping condition the contact surface abuts the second slide
surface to inhibit lateral movement of the sight element relative to the bar, whilst
permitting sliding axial movement of the sight element relative to the bar.
16. An archery bow having a sight according to any of claims 1 to 12, 14 and 15.