Conveyors: power-driven – Conveyor section – Live roll
Reexamination Certificate
2003-01-28
2004-08-10
Bidwell, James R. (Department: 3651)
Conveyors: power-driven
Conveyor section
Live roll
C198S781020
Reexamination Certificate
active
06772874
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a roller conveyor, and especially a roller conveyor in which a plurality of rollers between a pair of conveyor frames are driven by rotation driving means so that materials may be conveyed.
A roller conveyor for conveying materials on rollers is known in
FIG. 8
, which is a sectional view of a roller
101
between a pair of conveyor frames. In a roller body
102
for conveying materials, a driving force is connected and disconnected by a sprocket
103
driven by separate rotation driving means (not shown) via a pneumatic clutch mechanism
104
.
The pneumatic clutch mechanism
104
comprises a tubular member
107
which is rotatably mounted to a roller shaft
105
via a bearing
106
, and an elastic tube
108
between the tubular member
107
and the roller body
102
. The elastic tube
108
is expanded by air pressure introduced through a conduit
105
a
in the roller shaft
105
, and an outer surface
103
A at one end of the sprocket
103
is connected with an inner surface
102
A of the roller body
102
via the elastic tube
108
. Thus, when the pneumatic clutch mechanism
104
is actuated, a rotational force of the sprocket
103
is transmitted to the roller body
102
. To stop rotation of the roller body
102
, air supplied into the elastic tube
108
is exhausted by switching of a valve.
To control driving and stop of a roller body in a roller conveyor, a linear motor is also known, in which a roller body has a magnetic material and a plurality of driving coils by which N- and S-pole magnetic fluxes can be ejected on a floor.
However, in a device which comprises the pneumatic clutch mechanism
104
as shown in
FIG. 8
, it is necessary to control supply and exhaustion of air in each of the roller bodies depending on connection and disconnection of driving force to the roller bodies. Therefore, it is necessary to provide conduits or supply/exhaution control valve to make a system itself complicate.
In the linear motor, owing to difference of driving system, it is not possible to use known driving force transmission means, such as a belt and a chain, which not only lead increase in cost but also require control means for switching a magnetic flux signal to each of the rollers to drive and stop the roller bodies.
In the meantime, there are a two types of roller conveyors in
FIGS. 9
a
and
9
b
. In
FIG. 9
a
,
201
denotes a rotary shaft driven by a motor and has a plurality of driving pulleys
203
fixed thereon, corresponding to rollers
202
. A belt
204
is provided between the driving pulley
203
and the roller
202
, and the roller
202
b
is driven by the rotary shaft
201
via the belt
204
to convey materials “A”, “B”, “C”, “D”.
FIG. 9
a
illustrates eighteen rolls from
202
-
a
to
202
-
r
, and each four rolls are simultaneously braked. Four rolls
202
-
a
,
202
-
b
,
202
-
c
,
202
-
d
are braked by a brake
205
-
1
. Next four rolls
202
-
e
to
202
-
h
are braked by a brake
205
-
2
as well. Therefore, the materials “A” and “B” stop. On the contrary, the remaining rolls
202
-
l
to
202
-
r
are not braked since brakes
205
-
3
,
205
-
4
are lower, so that the materials “C” and “D” are conveyed.
In the roller conveyor in
FIG. 9
b
, a belt
208
is turned by rotation of a drive pulley
207
, and a plurality of rollers
209
which are frictionally engaged on the belt
208
are rotated by rotation of the belt
208
. Frictional engagement and disengagement between the belt
208
and the roller
209
are controlled by a clutch roll
210
. As shown in
FIG. 7
b
, the clutch rolls
210
-
1
and
210
-
2
are disposed at lower position, and the belt
208
is not engaged with the roller
209
. The rollers
209
-
a
to
209
-
i
are disengaged from the rotation driving means
207
,
208
and therefore act as free rollers which are freely rotatable in either direction. The remaining rollers
209
-
j
to
209
-
r
which are contacted on the belt
208
can be driven since clutch rolls
210
-
3
,
210
-
4
are disposed at higher position. In this situation, the clutch roll
210
-
3
is lowered and disengaged from the belt
208
, so that the material “D” is rolled on the rollers which are freely rotatable and can be arranged to contact the rear end of stopped material “C”.
However, in the roller conveyor as shown in
FIG. 9
a
, when the brake
205
is actuated, the roller
202
stops after it rotates by inertia force, so that the material “C” and “D” go forward to “C′” and “D′” which stop. The materials “A”, “B”, “C”, “D” are arranged with spaces, so that they are not able to be arranged in forward-contacted position.
In the roller conveyor as shown in
FIG. 9
b
, the roller
209
can be shifted to a driving or free roll by action of the clutch roll
210
, so that a material can be arranged to contact the rear end of stopped material. However, the belt
208
must be driven by full power and it is necessary to provide a conveyor belt having length corresponding to conveying distance of the roller conveyor.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages, it is an object of the present invention to provide a roller conveyor which allows driving and stopping of a roller body without special equipment or control means, the roller conveyor being functioned as a free roller rotatable in either direction when a roller body stops.
It is another object of the present invention to provide a roller conveyor which is easily variable in length and can be readily shifted between driving and free conditions, conveyed materials being able to be arranged in forward-contact position.
In order to achieve the objects, according to one aspect of the present invention, there is provided a roller conveyor comprising:
a pair of conveyor frames;
a plurality of rollers which are rotatably mounted between said pair of conveyor frames; and
rotation driving means for driving a roller or a set of rollers in the plurality of rollers to-convey materials, the roller or the set of rollers being able to be transformed to a free roller or rollers which are rotatable in either direction by an external force when said rotation driving means stop.
According to another aspect of the present invention, there is provided a roller conveyor comprising:
a pair of conveyor frames;
a plurality of rollers which are rotatably mounted between said pair of conveyor frames; and
rotation driving means for driving the rollers to covey materials, each of the rollers comprising a roller body which is rotatably mounted on a stationary roller shaft, and a driving force receiver which receives a rotational force from said rotation driving means, said roller conveyor further comprising driving force transmitting means for transmitting said rotational force to said roller body only when said driving force receiver receives the rotational force.
REFERENCES:
patent: 4063636 (1977-12-01), vom Stein
patent: 4269305 (1981-05-01), Fryatt
patent: 4362238 (1982-12-01), Rivette
patent: 5147024 (1992-09-01), Yamada
patent: 2742579 (1979-03-01), None
patent: 2219781 (1989-12-01), None
patent: 2241931 (1991-09-01), None
Harada Hiroyuki
Saida Hisato
Yamashita Yoshikazu
Bidwell James R.
Okamura Corporation
LandOfFree
Roller conveyor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Roller conveyor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Roller conveyor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3275425