U.S. patent application number 12/679524 was filed with the patent office on 2010-08-19 for cam with separated peripheral surfaces.
Invention is credited to Sergey Anatolievich Golovatyy, Pavel Vitalievich Ivanov, Sergey Olegovich Popov, Stanislav Svyatoslavovich Sagakov.
Application Number | 20100206284 12/679524 |
Document ID | / |
Family ID | 40568004 |
Filed Date | 2010-08-19 |
United States Patent
Application |
20100206284 |
Kind Code |
A1 |
Popov; Sergey Olegovich ; et
al. |
August 19, 2010 |
CAM WITH SEPARATED PERIPHERAL SURFACES
Abstract
This invention belongs to projectile throwing instruments that
use the energy of the strained hard body and can be used for the
design and construction of a missile throwing weapon--namely for a
bow and crossbow.
Inventors: |
Popov; Sergey Olegovich;
(Moscow, RU) ; Ivanov; Pavel Vitalievich; (Moscow,
RU) ; Golovatyy; Sergey Anatolievich; (Moscow,
RU) ; Sagakov; Stanislav Svyatoslavovich; (Moscow,
RU) |
Correspondence
Address: |
KEVIN J. MCNEELY, ESQ.
5335 WISCONSON AVENUE, NW, SUITE 440
WASHINGTON
DC
20015
US
|
Family ID: |
40568004 |
Appl. No.: |
12/679524 |
Filed: |
September 9, 2008 |
PCT Filed: |
September 9, 2008 |
PCT NO: |
PCT/RU08/00588 |
371 Date: |
March 23, 2010 |
Current U.S.
Class: |
124/88 |
Current CPC
Class: |
F41B 5/105 20130101;
F41B 5/14 20130101; F41B 5/10 20130101 |
Class at
Publication: |
124/88 |
International
Class: |
F41B 5/14 20060101
F41B005/14 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 16, 2007 |
RU |
2007138057 |
Claims
1. A cam with separated peripheral surfaces for the projectile
throwing instrument is installed on the free end of the thrower's
limb, which is able to spin and has peripheral surfaces that give
way to the string and cable strings. With this, the string's
peripheral surface stands from the cable strings' peripheral
surfaces at a distance far enough to allow for the string and at
least one cable string, in which the distance between the string's
peripheral surface and the nearest peripheral surface is enough for
the cable string not to hinder the path of the thrown projectile.
Moreover, the cable strings are completely intercrossed.
2. The cam of claim 1 wherein the cable strings are not
intercrossed.
3. The cam of claim 1 wherein the symmetry axis coincides with the
spinning axis.
4. The cam of claim 1 wherein the symmetry axis stands off from the
spinning axis.
5. The cam of claim 1 wherein the cam is of a round shape.
6. The cam of claim 1 wherein the cam is of a non-round shape.
Description
[0001] This invention belongs to projectile throwing instruments
that use the energy of the strained hard body and can be used for
the design and construction of a missile throwing weapon--namely
for a bow and crossbow.
[0002] Since the middle of the 20.sup.th century, these cams have
been widely used for the designing of bows and crossbows. According
to the common technique, the cams have at least two peripheral
surfaces on which a working bowstring and cable strings are placed.
The cams are mainly placed on the free ends of the limbs. The main
characteristic feature and advantage of cam usage in the projectile
throwing instrument design is the release of the pulling force in
the tension endpoint and the increase of the thrown projectile's
speed at the moment of its shooting. In addition, cam throwing
devices are the fastest and are rather compact. All of the
technical solutions that aimed to perfect the design of the
projectile throwing instrument according to the previous technical
level are mainly directed towards changing the geometrical shape of
the cam. However, with all the diversity of cam shapes and designs,
all of them have two common characteristic features. The first one
is the cam peripheral surfaces' location in the middle part of the
holding axle by means of which the cam is fixed onto a limb.
Secondly, the peripheral surfaces are situated at a short distance
from each other. In such a location of the peripheral surfaces, the
cable strings are located near the working bowstring and hinder the
path of the thrown missile. That is why during the design of
projectile throwing instruments there appears the necessity to
forcedly turn the cable strings away from the working string. For
this, various constructions of cable string retractor assemblies
are used. The main drawback in the well-known cam constructions is
that they cause additional friction on the joints and spiral
torsional strains that are passed by the cable strings to the
limbs.
[0003] There is a well-known design (U.S. Pat. No. 6,659,096B1),
which contains a cam fixed onto the flexible element's free end,
which is able to spin and has peripheral surfaces that give way to
the working string and cable strings. These surfaces are situated
in the middle part of the cam's axle that is fixed to the limb at a
short distance from one another.
[0004] The main drawback of the bow mentioned above is the
necessity to turn the cable strings away from the working
string.
[0005] There is a crossbow design (U.S. Pat. No. 6,460,528 B1) that
contains the cam fixed on the flexible element's free end, which is
able to spin and has peripheral surfaces that give way to the
working string and cable strings. These surfaces are situated in
the middle part of the cam's axle that is fixed to the limb at a
short distance from one another.
[0006] The main drawback of the crossbow mentioned above is the
necessity to turn the cable strings away from the working
string.
[0007] The technical problem, which is to be solved by means of the
given invention implies the creation of an improved cam design that
will allow for the manufacturing of cam throwers without turning
away the joints of the cable strings, which in its turn will
increase the efficiency of the work of the limbs.
[0008] The technical result provided by the usage of the present
invention consists in the increase of the maximum starting speed of
the thrown missile, improved shooting accuracy and density, as well
as the decrease of its noise and vibration.
[0009] To achieve the mentioned technical result it is recommended
to use the divided cam of the bow or crossbow's string tension that
are placed on the flexible element's free end, which is able to
spin and has peripheral surfaces that give way to the working
string and at least one cable string, in which this string's
peripheral surface is located at the nearest peripheral surface of
the cable string at a distance at which the cable string does not
in any way obstruct the path of the thrown missile.
[0010] The cam represents the spinning part of a wheel shape or of
a complex non-round shape including the shifted spinning axis.
[0011] The system consisting of at least one designed cam and
containing limbs with free ends is to be placed on the projectile
throwing instrument. On the free ends the cams able to spin, and
they have peripheral surfaces that give way to the string and cable
strings. With this, the string's peripheral surface stands from the
cable strings' peripheral surfaces at a distance that is enough to
expel the joint of the cable strings' peripheral surfaces and
turn-away out of the projectile throwing instrument's design.
[0012] In most cases, the divided cam represents the spinning part
of the round, elliptic, or any other shape known in the given
branch of engineering. The peripheral surface, which is shaped like
a string channel, is situated in the upper part of the cam. In the
lower part of the cam, at least one peripheral surface for cable
strings is located. The middle part of the divided cam serves to
separate the string's peripheral surface and cable strings'
peripheral surfaces within a distance at which the cable strings do
not prevent shooting. The upper and lower parts of the divided cam
are firmly interconnected and turn around the spinning axis
synchronously. The constructive use of the divided cam and used
materials can be various and can be used in the given branch of
engineering. To decrease the size, the limbs can be placed in the
middle part of the divided cam between the string's peripheral
surface and the cable strings' peripheral surface. The divided
cam's spinning axis can go through the cam's center or be shifted
relative to the cam's center. Cable strings can be placed on the
peripheral surfaces in the cam's lower part in parallel or
intercross.
[0013] The divided cams can be placed on the crossbow, on the bow,
or on any other suitable projectile throwing instrument.
[0014] Furthermore, the present invention will be described in
detail using diagrams.
[0015] FIG. 1 shows the system of cams with the joint of cable
strings' turn-away according to the known engineering level.
[0016] FIG. 2 shows the system of divided cams with crossed cable
strings according to the present invention.
[0017] FIG. 3 shows the system of divided cams with parallel cable
strings according to the present invention.
[0018] The following legend is used in the diagrams: limbs 1, cam's
holding axis 2, cam accordingly to the known engineering level 3,
string's peripheral surface 4, peripheral surface for one cable
string 5, peripheral surface for another cable string 6, thrown
missile 7, joint of cable strings' turn-away 8, the string's path
of motion 9, motion path of one cable string 10, motion path of
another cable string 11, middle part of divided cam 12, upper part
of divided cam 13, and the lower part of divided cam 14.
[0019] Preparation and shooting of the bow or crossbow using the
designed cam construction does not differ from the preparation and
shooting of a bow or crossbow using the cam-prototype.
[0020] The use of the mentioned technical solution allows for an
increase of the maximum starting speed of the thrown projectile by
approximately 15%, accuracy and the density of shooting by
approximately 10%, and at the same time a decrease in the noise and
vibration of the shooting.
* * * * *