U.S. patent application number 09/955784 was filed with the patent office on 2002-09-12 for vibratory conveyor.
This patent application is currently assigned to Shinko Electric Co. Ltd.. Invention is credited to Ikeda, Masahiro, Kato, Kazumichi, Kimura, Tetsuyuki, Muragishi, Yasushi, Sekine, Toshiro.
Application Number | 20020125109 09/955784 |
Document ID | / |
Family ID | 27296260 |
Filed Date | 2002-09-12 |
United States Patent
Application |
20020125109 |
Kind Code |
A1 |
Ikeda, Masahiro ; et
al. |
September 12, 2002 |
VIBRATORY CONVEYOR
Abstract
In a vibratory conveyor which includes a trough for transporting
objects, exciting mechanism for vibrating the trough in a
horizontal direction and supporting mechanism for supporting the
trough so as to be vibratile in the horizontal direction, the
exciting mechanism is a linear motor, one of the primary and
secondary sides of the linear motor is fixed to the trough and the
other is facing to the one with a predetermined gap and so arranged
as to be vibratile relative to the one.
Inventors: |
Ikeda, Masahiro;
(Toyohashi-shi, JP) ; Sekine, Toshiro;
(Toyohashi-shi, JP) ; Kato, Kazumichi; (Ise-shi,
JP) ; Muragishi, Yasushi; (Ise-shi, JP) ;
Kimura, Tetsuyuki; (Ise-shi, JP) |
Correspondence
Address: |
Floyd B. Carothers
CAROTHERS AND CAROTHERS
Suite 500
445 Fort Pitt Boulevard
Pittsburgh
PA
15219
US
|
Assignee: |
Shinko Electric Co. Ltd.
7-2-14, Toyo-Cho, Koto-Ku
Tokyo
JP
|
Family ID: |
27296260 |
Appl. No.: |
09/955784 |
Filed: |
September 19, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09955784 |
Sep 19, 2001 |
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09255283 |
Feb 22, 1999 |
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6318542 |
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Current U.S.
Class: |
198/752.1 |
Current CPC
Class: |
B65G 27/32 20130101;
B65G 27/08 20130101; B65G 27/30 20130101; B65G 27/24 20130101 |
Class at
Publication: |
198/752.1 |
International
Class: |
B65G 027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 23, 1998 |
JP |
57441/1998 |
May 19, 1998 |
JP |
153853/1998 |
Jul 21, 1998 |
JP |
221021/1998 |
Claims
What is claimed is:
1. In a vibratory conveyor which includes a trough for transporting
objects therealong in a longitudinal direction, exciting means for
vibrating said trough in a direction horizontal to said
longitudinal direction and supporting means for supporting said
trough so as to be vibratile in said horizontal direction, the
improvements comprising said exciting means including linear motor
means having primary and secondary sides with one of said sides
being fixed to said trough and the other of said sides facing to
said one side with a predetermined gap and so arranged as to be
vibratile relative to said one side, said trough being elongated,
said linear motor means consisting of plural linear motors, and
means for supplying a drive command to said linear motors for
driving them in synchronization with each other.
2. A vibratory conveyor according to claim 1 in which said drive
command is a command selected from the group consisting of a
position command, a speed command, a force command and an
acceleration command.
3. A vibratory conveyor according to claim 1 in which said
supporting means is comprised of wheel means rotatably supported by
said trough or ground, and guide rail means having an arcuate
surface for guiding said wheel means.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a vibratory conveyor which conveys
or transports material or various objects by vibration or solely by
a sliding action.
[0003] 2. Description of the Prior Art
[0004] In most of vibratory conveyors which conveys object in a
straight line, a trough is lenearly vibrated slant to the conveying
surface. The objects are jumping repeatedly and are moved
forwardly. The free flight of metal objects end with an impact
which would increase noise. Free flight of the fragile objects ends
with an impact which might lead to damage of the fragile
objects.
[0005] In order to avoid these undesirable effects, the so-called
"reciprocating conveyor" is developed in which the objects are
conveyed solely by a sliding action, i.e., without leaving the
surface of the conveyor. One example of the reciprocating conveyors
is shown in FIG. 1 and is disclosed in the Japanese Opening Gazette
123812/1980.
[0006] A reciprocating conveyor 100 includes a trough 150 which is
U-shaped in cross-section and vibrated by an exciter 110 in a
horizontal direction. The objects are transported rightwards in the
trough 150.
[0007] The trough 150 is supported on a base 109 through vertical
leaf springs 152. The upper and lower ends of the leaf springs 152
are fixed to the trough 150 and the base 109 through fixing members
153aa nd 153b, respectively. The trough 150 is vibrated in the
direction X by the exciter 110. The latter is combined with the
former by horizontal leaf springs 129. The left and right ends of
the leaf springs 129 are fixed to the exciter 110 and trough 150
through angular members 154 and 114 (FIG. 2). The leaf springs 152
are rigid in its longitudinal direction, while they are flexible in
its lateral direction. Little force is applied in the vertical
direction to the trough 150 by cooperation of the leaf springs 129
and coil springs 128 supporting the exciter 110 from the
latter.
[0008] FIG. 2 is a plan view of the exciter 110 and portions
relating thereto. FIG. 3 is a cross-sectional view taken along the
line III - III in FIG. 2. As shown in FIG. 3, the exciter 110
consists of a pair of exciting mechanisms 131aa nd 131b which are
attached to housings 111aa nd 111b (FIG. 1), respectively. They are
fixed to each other through spacers 127 as one body, and supported
on the base 109 through the coil springs 128.
[0009] The exciting mechanisms 131aa nd 131b are equal to each
other in construction, and are arranged symmetrically with respect
to each other. Only the construction of the exciting mechanism 131a
will be described. A first rotational shaft 135a is supported by
bearings 133aa nd 134a which are fixed to the housing 111a. A first
semi-circular unbalance weight 136a of larger diameter is fixed to
the first rotational shaft 135a. Similarly, a second rotational
shaft 145a is supported by bearing 143aa nd 144a which are fixed to
the housing 111a. A second semicircular unbalance weight 146a of
smaller diameter is fixed to the second rotational shaft 145a.
[0010] An electric motor 121a is fixed on a back wall portion of
the housing 111a. A belt 123a is wound on a pulley 122a fixed to a
rotary shaft of the electric-motor 121aa nd another pulley 137a
fixed to one end of the first rotary shaft 135a. A large-diameter
gear 139a is fixed to another end of the first rotary shaft 135a,
and engaged with a small-diameter gear 149a fixed to one end of the
second rotary shaft 145a. The number of teeth of the small-diameter
gear 149a is half of that of the large-diameter gear 139a. Thus,
the second rotary shaft 145a is rotated in opposite direction to
the first rotary shaft 135a, at the twice angular speed as the
latter. Suffix b is attached to those of the other exciting
mechanism 131b which correspond to the parts of the one exciting
mechanism 131a, and the description of which will be omitted.
[0011] The first and second unbalance weights 136a, 136b and 146a,
146b of the exciting mechanisms 131aand 131b are fixed to the first
and second rotary shafts 135a, 135b and 145a, 145b, respectively in
the angular phase relationship as shown in FIG. 3. Accordingly, the
composite force generated by the exciting mechanisms 131aa nd 131b,
in the vertical direction Y is always equal to zero.
[0012] The construction of the reciprocating conveyor 100 of the
prior art has been described. Next, its operation will be
described.
[0013] The two first unbalance weights 136aa re fixed to the rotary
shaft 135a in the exciting mechanism 131a. However, they are
equivalent in effect to the one first unbalance weight which is
double in weight and is fixed to the center of the rotary shaft
135a. For simplification of the description, it is assumed that the
one unbalance weight having the weight double as the first
unbalance weight 136a is fixed to the center of the rotary shaft
135a. Similarly in the other exciting mechanism 131b, it is assumed
that the one unbalance weight having the weight double as the first
unbalance weight 136b is fixed to the center of the rotary shaft
135b.
[0014] Referring to FIG. 3, the electric motors 121aand 121b are
rotated in opposite directions, in synchronization with each other.
In the one exciting mechanism 131a, the first rotary shaft 135a is
rotated in clockwise direction through the belt 123a, while the
second rotary shaft 145a is rotated in anti-clockwise direction at
the twice angular speed, since the larger gears 139aa nd the small
gear 149aa re engaged with each other.
[0015] In the other exciting mechanism 131b, the first rotary shaft
135b is rotated in anti-clockwise direction through the belt 123b,
while the second rotary shaft 145b is rotated in clockwise
directions at the twice angular speed, since the gears 139b and
149b are engaged with each other.
[0016] As shown in FIG. 4, the X-components Fax, Fbx of the
centrifugal forces Fa, Fb generated from the first unbalance
weights 136a, 136b in t seconds, are as follows:
[0017] Fa.sub.x=-Fasin(.omega.t), Fb.sub.x=-Fbsin(.omega.t) where
.omega. represents angular speed.
[0018] Accordingly, F.sub.x=Fa.sub.x+Fb.sub.x=-2Fasin(.omega.t)
[0019] Similarly, the X-components fax, fbx of the centrifugal
forces fa, fb generated from the second unbalance weights 146a,
146b,
[0020] fa.sub.x=fasin(2.omega.t), are as follows:
fb.sub.x=fbsin(2.omega.t- ).
[0021] Accordingly, the composite force f.sub.x is as follows:
[0022] f.sub.x=fa.sub.x+fb.sub.x=2fasin(2.omega.t)
[0023] Accordingly, the X-composite force Q.sub.x as whole,
Q.sub.x=F.sub.x+f.sub.x=-2Fasin(.omega.t)+2fasin(2.omega.t)
[0024] The trough 150 is excited by the force Q.sub.X. The
Y-components Fay, Fby of the centrifugal forces Fa, Fb generated
from the first unbalance weights 136a, 136b in t seconds is as
follows:
[0025] Fa.sub.y=-Facos(.omega.t), Fb.sub.y=Fbcos(.omega.t)
[0026] The composite force F.sub.y is as follows:
[0027] F.sub.y=Fa.sub.y+Fb.sub.y=0
[0028] Similarly, the Y-component fay, fby of the centrifugal
forces fa, fb generated from the second unbalance weights 146a,
146b are as follows:
[0029] fa.sub.y=-facos(2.omega.t),fb.sub.y=facos(2.omega.t)
[0030] Thus, the composite force f.sub.y is as follows:
[0031] f.sub.y=fa.sub.y+fb.sub.y=0
[0032] Accordingly, the Y-composite force Q.sub.y of the
centrifugal forces generated from the first and second unbalance
weights 136a, 136b, and 146a, 146b, are always equal to zero.
[0033] Q.sub.y=F.sub.y+f.sub.y=0
[0034] The composite force Q.sub.x is applied to the trough 150
only in the X-direction.
[0035]
Q.sub.x=F.sub.x+f.sub.x=-2Fasin(.omega.t)+2fasin(2.omega.t).
[0036] In graph shown in FIG. 5A, axis of ordinates represents
exciting force in the X-direction, and axis of abscissas represents
time. The composite forces Q.sub.x, F.sub.x and f.sub.x change with
time, as shown in FIG. 5A, where F.sub.x=2f.sub.x.
[0037] The reciprocating conveyor 100 is composed of one-mass
system, according to the theory of the vibration technology. The
resonant frequency of the reciprocating conveyor 100 is determined
by a spring constant of all of the leaf springs 152, and a mass
supported by the leaf springs 152.
[0038] When the spring constant of all of the leaf springs 152 is
sufficiently small, and the trough 150 is vibrated by the force of
higher frequency than the resonant frequency, the phase defference
between the force Q.sub.x and the displacement of the trough 150 is
equal to 180 degrees. Thus, the trough 150 is displaced as shown by
curve D in the graph of FIG. 5A. The trough 150 moves forwards to
the point p at the lower speed and moves backwards to the point q
from the point p at the higher speed. FIG. 5B shows schematically
such changes. The exciting force overcomes the frictional force
between the object to be conveyed, and the conveying surface of the
trough 150 during the high speed backward-movement period T.sub.1
to T.sub.2. Thus, only the trough 150 moves backwards, and the
object remands on the original position. The object and the trough
150 move together during the low spread period T.sub.2 to T.sub.3.
Accordingly, the object is transported forwards.
[0039] The first and second unbalance weights 136a, 136b and 146a,
146b are rotated in the above described manner so that the trough
150 is vibrated only in the horizontal direction. The belts 123a,
123b and gears 139a, 139b are aranged in the exciting mechanism
110, which make noise. The exciting mechanism 110 is complicated in
construction.
[0040] In the above-described reciprocating conveyor 100, the
vibration of the trough 150 is non-sinusoidal and horizontal. The
amplitude of the vibration is determined by the exciting force
Q.sub.x which is generated by rotation of the first and second
unbalance weights 136a, 136b and 146a, 146b. The exciting force
Q.sub.x is determined by the centrifugal forces of the first and
second unbalance weights 136a, 136b and 146a, 146b. The frequency
of the exciting force Q.sub.x is determined by the rotational speed
of the electric motors 121a, 121b which drive the first and second
unbalance weights 136a, 136b and 146a, 146b. Thus, the rotational
speed of the electric motors 121a, 121b and the centrifugal forces
of the first and second unbalance weights 136a, 136b, and 146aa nd
146b should be adjusted to obtain a desired vibration. The
construction should be changed. It is difficult to obtain an
arbitrary vibration by the prior art exciting mechanism 110.
Accordingly, it is difficult to adjust a transporting speed and it
is impossible to adjust the exciting mechanism so as to transport
objects efficiently.
[0041] In order to avoid the above described disadvantages, the
assignee developed such a reciprocating conveyor that uses a linear
motor as an excitor in which pole change of primary windings and
polarity change-over are made at the same time ( Japanese
Publication number 35395/1779). However, this reciprocating
conveyor generates the reaction force which is transmitted to the
base through the linear motor. In order to avoid the disadvantage,
it is described that two troughs are arranged in line with each
other, and they are excited in opposite directions by the
respective linear motors, in the same Publication. To cancel the
reaction forces from each other, such a complicated control should
be effected that the respective troughs are slowly moved forwards
and rapidly moved backwards in synchronization with each other.
SUMMARY OF THE INVENTION
[0042] It is an object of this Invention to provide a vibratory
conveyor or reciprocating conveyor which is simple in construction,
makes little noise, can easily adjust a transporting speed of
object and transmits little reaction force to the mounting
base.
[0043] In accordance with an aspect of this Invention, in a
vibratory conveyor which includes a trough for transporting
objects, exciting means for vibrating said trough in a horizontal
direction and supporting means for supporting said trough so as to
be vibratile in said horizontal direction, the improvements in
which said exciting means is linear motor means, one of the primary
and secondary sides of said linear motor means is fixed to said
trough and the other is facing to said one with a predetermined gap
and so arranged as to be vibratile relative to said one.
[0044] In accordance with another aspect of the inventions, in a
vibratory conveyor which includes a trough for transporting
objects, exciting means for vibrating said trough in a horizontal
direction and supporting means for supporting said trough so as to
be vibratile in said horizontal direction, the improvements in
which said exciting means is linear motor means, one of the primary
and secondary sides of said linear motor means is fixed to said
trough and the other is facing to said one with a predetermined gap
and supported through elastic material or vibration absorbing
material on a mounting base.
[0045] The other objects, features, and advantages of the present
invention will be more readily understood upon consideration of the
following detailed description of the preferred embodiments of the
invention, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] FIG. 1 is a side view of a vibratory conveyor of the prior
art.
[0047] FIG. 2 is a plan view of an exciter and portions relating
thereto in the vibratory conveyor of the prior art.
[0048] FIG. 3 is a cross-sectional view take along the line
[III]-[III] in FIG. 2.
[0049] FIG. 4 is a front view of unbalance weights in the prior art
for explaiing operations of the excitor.
[0050] FIG. 5 is a graph showing the relationship between the
exciting force generated from unbalance weight and the trough
movement. FIG. 5A shows time charts of the force and displacement.
FIG. 5B shows the trough movement.
[0051] FIG. 6 is a perspective view of a vibratory conveyor
according to a first embodiment of this invention.
[0052] FIG. 7 is a side view of a vibratory conveyor according to
the first embodiment.
[0053] FIG. 8 is a perspective view of a linear motor used in the
first embodiment.
[0054] FIG. 9 is a view showing principal operations of the linear
motor of FIG. 8.
[0055] FIG. 10 is a perspective view of a vibratory conveyor
according to a second embodiment of this invention.
[0056] FIG. 11 is a side view of the conveyor according to the
second embodiment.
[0057] FIG. 12 is a perspective view of a linear motor used in the
second embodiment.
[0058] FIG. 13 is a cross-sectional view taken along the line
[XIII]-[XIII] in FIG. 11.
[0059] FIG. 14 is a perspective view of a vibratory conveyor
according to a third embodiment of this invention.
[0060] FIG. 15 is a side view of the vibratory conveyor according
to the third embodiment.
[0061] FIG. 16 is a perspective view of a linear motor used in the
third embodiment.
[0062] FIG. 17 is a perspective view of a vibratory conveyor
according to a fourth embodiment of this invention.
[0063] FIG. 18 is a perspective view of a vibratory conveyor
according to a fifth embodiment of this invention.
[0064] FIG. 19 is a side view showing one principle of this
invention, FIG. 19A is one form of the one principle and FIG. 19B
is another form of the one principle of this invention.
[0065] FIG. 20 is a side view showing the other principle of this
invention, FIG. 20A is one form of the other principle of this
invention and FIG. 20B is another form of the other principle of
this invention.
[0066] FIG. 21 is a side view of a vibratory conveyor according to
a sixth embodiment of this invention.
[0067] FIG. 22 is a side view of a vibratory conveyor according to
a senventh embodiment of this invention.
[0068] FIG. 23 is a side view of a vibratory conveyor according to
an eighth embodiment of this invention.
[0069] FIG. 24 is a cross-sectional view taken along the line
[XXIV]-[XXIV] in FIG. 23.
[0070] FIG. 25 is a side view of a vibratory conveyor according to
a ninth embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0071] FIG. 19 shows a principle of the first invention, and FIG.
19A shows one form of the principle.
[0072] A trough 70 is so supported as to be vibratile in a
horizontal direction, by support members 75 and 75. A primary side
71' of a linear motor 73' which includes coils C, is fixed to the
trough 70. A secondary side 72' of the linear motor 73' is facing
to the primary side 71' thereof with a predetermined gap g', and is
so arranged as to be vibratile in opposite direction to the trough
70. FIG. 19B shows another form of the principle.
[0073] A trough 70 is so supported as to be vibratile in a
horizontal direction, by support members 75 and 75. A secondary
side 72' of a linear motor 73' is fixed to the trough 70. A primary
side 71' of the linear motor 73' is facing to the secondary side
72' thereof with a predetermined gap g' , and is so arranged as to
be vibratile in opposite direction to the trough 70. According to
the second invention, in a vibratory conveyor which includes a
trough for transporting objects, exciting means for vibrating said
trough in a horizontal direction and supporting means for
supporting said trough so as to be vibratile in said horizontal
direction, said exciting means is linear motor means, one of the
primary and secondary sides of said linear motor means is fixed to
said trough and the other is facing to said one with a
predetermined gap and supported on a mounting base or ground
through elastic material or vibration-absorbing material. FIG. 20
shows a principle of the second invention, and FIG. 20A shows one
form of the principle.
[0074] A trough 70 is so supported as to be vibratile in a
horizontal direction, by support members 75 and 75. A primary side
71 of a linear motor 73 which includes coils C, is fixed to the
trough 70. A secondary side 72 of the linear motor 73 is facing to
the primary side 71 thereof with a predetermined gap g, and is
supported through elastic material or vibration-absorbing material
74 on a mounting base.
[0075] FIG. 20B shows another form of the principle.
[0076] A trough 70 is so supported as to be vibratile in a
horizontal direction, by support members 75 and 75. A secondary
side 72 of a linear motor 73 is fixed to the trough 70. A primary
side 71 of the linear motor 73 is facing to the secondary side 72
thereof with a predetermined gap g, and is supported through
elastic material or vibration-absorbing material 74 on a mounting
base.
[0077] With the above-described arrangements of these inventions,
the exciting mechanism is simple in construction, and makes little
noise, since no gears are used in contrast to the prior art. The
control is simple for transporting objects efficiently.
[0078] In the first invention, the reaction force is cancelled with
movement of the primary or secondary side in opposite direction to
the trough 70.
[0079] In the second invention, the reaction force is absorbed with
the elastic material or vibration-absorbing material, when the
trough 70 is vibrated. Reaction force is not transmitted to the
mounting base. When the elastic material or vibration-absorbing
material is plate-like or pillar-like, the arrangement can be
simple.
[0080] Next, embodiments of this invention will be described with
reference to the drawings.
[0081] FIG. 6 shows a perspective view of a vibratory conveyor 1
according to the first embodiment of this invention, and FIG. 7
shows a front view. In the vibratory conveyor 1, a trough 7 is
supported by two support mechanism 11 which are swingably attached
to the trough 7 at the top ends forming hinge portions J. An
exciting source is attached to the trough 7. It is a linear motor
16. Not-shown objects are included in the trough 7. The objects are
transported from left to right as shown by the arrow f. In FIG. 6,
the trough 7 is shown by the dot-dash lines in order to clearly
show construction of the support mechanism 11 including links and
the linear motor 16.
[0082] The support mechanism 11 consists of two supporting legs 12,
12', a movable portion 13 and two connecting portions 14. The
supporting legs 12, 12' have inverted-L shaped form, and the bottom
portions 12b and 12b' are suppprted on the mounting surface or
ground G. The horizontal portions 12a, 12a' (FIG. 7) of the
supporting legs 12, 12' are combined with the end portions 14a,
14a' (FIG. 7) of the connecting portions 14. Pins P are inserted
into the end portion 14a, 14a' of the connecting portions 14 and so
construct hinge portions H, H'. The movable portions 13 at their
horizontal end portions 13b, 13b' are combined with the end
portions 14b, 14b' of the connecting portions 14. Pins P are
inserted into the end portions 14b, 14b'. Thus, they form hinge
portions I, I'. Accordingly, with the hinge portions H, H' and I,
I', the movable portions 13 are swingable. The movable portions 13
are swinged as shown by the dot-dash lines and two-dot dash lines
in FIG. 7. The horizontal portions 13a can be swinged in the
horizontal direction. Thus, the trough 7 attached to the horizontal
portions 13a (FIG. 6) of the movable portions 13 can be supported
so as to be vibratile in the transporting direction of the
object.
[0083] The linear motor 16 of this embodiment, as shown in FIG. 7,
consists of secondary members 17 fixed to the bottom of the trough
7 and primary members 18 supported by wheels or disk 18a on the
secondary members 17. The secondary members 17 consist of
horizontal portion 17aa nd support potions 17b and 17b' fixed to
both ends of the horizontal portion 17a. The secondary members 17
are U-shaped as one body.
[0084] A pair of grooves 17aa, 17aa(FIG. 8) extending in the
horizontal direction are formed in the horizontal portion 17a of
the secondary members 17.
[0085] The wheels 18aa re guided in the grooves 17aa, 17aa.
Magnetic teeth 17abare arranged between the grooves 17aa, 17aain
vertical direction to the transporting direction of the object.
[0086] FIG. 8 is an enlarged perspective view of the linear motor
16. The wheels 18a in the primary members 18 of the linear motor 16
are fixed to not-shown shafts. An air gap s is formed by wheels
18a. The primary members 18 includes three magnetic poles U, V, W
on which the coils 19a, 19b, 19c are wound. Laminar permanent
magnets M(three) are inserted in the magnetic poles U, V, W as
shown in FIG. 9. Three-phase alternating currents shifted from each
other by 120 degrees in phase are supplied to the coils l9a, 19b
and 19c. An additional mass 30 is fixed through mounting members 20
to the primary members 18. The primary members 18 are spaced from
the mounting surface G in the air. The vibratory conveyor 1 of this
embodiment is constructed in the above described member.
[0087] Next, operations of the linear motor 16 of this embodiment
which is of the high density type, will be described. The
operations will be described with reference to FIG. 9.
[0088] The permanent magnets M are so arranged that the same
polarities are facing to each other. When the currents are flowed
through the coils 19a, 19b, 19c as shown by the marks and
.circle-w/dot., magnetic flux flows in the cores of the primary and
secondary members 17, 18 as shown by the arrows. When the magnetic
flux from the permanent magnets M is in the same direction as the
magnetic flux due to the current-flowing through the coils 19d,
19b, 19c, the latter and former are added to each other. When the
former is in the opposite direction to the latter, they are
cancelled from each other. As the result, the thrust or horizontal
drive force of the linear motor 16 is increased. Currents are
flowed through the coils 19a, 19b and 19c, shifted in phase 120
degrees and 240 degrees. Attractive forces are generated between
the magnetic teeth 17ab of the secondary members 17 and the poles
U, V, W of the primary members 18. Thus, the primary members 18 are
moved leftwards.
[0089] The currents flowing through the coils 19a, 19b and 19c are
shifted from each other in phase 120 degrees. The magnetic
attractive force is generated between the magnetic teeth 17ab and
the magnetic poles U, V, W. Thus, the primary members 18 are moved
leftwards. The primary members 18 slide on the secondary members 17
through the wheels 18a. The secondary members 17 at the horizontal
portion 17a receive the reaction force from the primary members 18.
Accordingly, the secondary members 17 are moved rightwards in
opposite direction to the movement of the primary members 18. Thus,
the trough 7 fixed to the secondary members 17 is moved rightwards.
The current is so adjusted that the primary members 18 is moved
forwards slowly and backwards rapidly.
[0090] With the above described operation, the trough 7 is moved
rapidly in the forward direction and then moved back slowly in the
backward direction. Thus, the object is moved rightwards.
[0091] In this embodiment, the linear motor 16 is used as a driving
exciting source for vibrating horizontal the trough of the
vibratory conveyor 1. Accordingly, driving forces of an arbitrary
form can be generated and so the vibration of a desired form can be
obtained. The object can be transported efficiently. The change of
moving direction and the transporting speed can be easily
controlled without complicated construction. No gear is used.
Little noise is made. Further, in the vibratory conveyor 1 of this
embodiment, the secondary side of the linear motor 16 receives
reactive force due to movement of the primary members 18, so that
the trough 7 is vibrated. Accordingly, reactive force is not
transmitted to the mounting surface on which the vibratory conveyor
is mounted. Further, in this embodiment, the mass 30 is fixed to
the primary members 18 and so the movement of the primary members
18 in the opposite direction to that of the trough 7 can be
reduced, so that the primary member 18 does not collide with the
portions 17b, 17b of the secondary members 17. The vibratory
conveyor 1 can be surely vibrated in the horizontal direction by
the supporting mechanism 17b and 17b' of the secondary members
17.
[0092] Next, the second embodiment will be described. Those which
correspond to the parts in the first embodiment, are denoted by the
same reference numerals. Detailed description will be omitted. A
vibratory conveyor 2 of the second embodiment is shown
perspectively, in FIG. 10. The front view is shown in FIG. 11.
Plural supporters 21 are used instead of the support mechanism 11.
A linear motor 26 is used instead of the linear motor 16 of the
first embodiment. The trough 7 is shown by the dot-dash lines in
order to clearly show the supporters 21 and linear motor 26.
[0093] Supporters 21 includes a pendulum mechanism. It consists of
the inverted-V shaped support member 22 and swing levers 23
suspended from the top of the support member 22 at pin p'. As shown
in FIG. 11, the linear motor 26 consists of a primary member 28
fixed on the bottom of the trough 7 and the secondary member 27
inserting through the primary member 28. FIG. 12 shows an enlarged
view of the linear motor 26. FIG. 13 is a cross-section view take
along the line [XIII ]-[XIII ] in FIG. 11. A primary member 28
consists of horizontal portion 28aa nd support members 28b, 28b'
supporting the horizontal portion 28a. It is U-shaped. The upper
surface of support members 28b, 28b' are fixed on the trough 7. The
coils 19a, 19b and 19c and not-shown laminar permanent magnets
(three) are arranged in the support members 28b, 28b'. Rollers 29a
of non-magnet material (FIG. 13) are arranged in a horizontal
portion 28a of the primary member 28, and the upper portions are
projected from the horizontal portion 28aa nd supports slidably the
secondary member 27. The secondary members 27 is parallel-piped,
extending in the transporting direction of the trough 7. Grooves
27aaare formed in the upper and lower portions of the side walls
27a. The wheels 29b are supported by shafts 9 held by the mounting
members 8. Plural magnet teeth 27ab are so formed in the central so
as to face the magnet poles U, V, W. Air gap s' is formed by
fitting the wheels 29b to grooves 27aabetween magnet teeth 27ab and
magnet poles U, V, W. Further, the mounting member 20' is arranged
in the secondary members 27. An additional mass 30' of metal in the
form of block is fixed to the mounting members 20'. In this
embodiment, the secondary members 27 are suspended from the primary
member 28 in the air. It is spaced from the mounting ground G.
[0094] The construction of the vibratory conveyor 2 of the second
embodiment has been described. Next, operaion will be described.
Operation principle of the linear motor 26 is equal to the linear
motor 16 of the first embodiment. Accordingly, the detailed
description will be omitted Alternating currents are flowed through
the coils 19a, 19b and 19c of the linear motor 26, shifted from
other in phase by 120 degrees. As described in the first
embodiment, magnet attractive force is generated between the
magnet-teeth 27ab and the poles U,V,W. Thus, the primary member 28
is moved rightwards. In this embodiment, the trough 7 is fixed to
the primary member 28.
[0095] The secondary member 27 is engaged with the primary memeber
28 through the rollers 29a nd the wheels 29b.
[0096] Accordingly, it receive the opposite force to the driving
force of the primary member 28. Thus, it is moved leftwards. The
current is so controlled that the trough 7 is moved slowly with the
object to be transported. The supporters 21 are swingable in the
manner as shown by the two-dot-dash lines and dot-dash line in FIG.
11.
[0097] The current is flowed through the coils 19a, 19b, 19c wound
on the poles U,V,W. The trough 7 fixed to primary member 28 is
moved leftwards and the secondary member 27 is moved rightwards.
The current is so adjusted that the primary member 28 can be moved
rapidly. The supporters 21 supporting the trough 7 swing in the
manner shown by dot-dash lines and two-dot-dashlines in FIG.
11.
[0098] The trough 7 is moved slowly in the transporting direction
of the object and moved rapidly in opposite direction to the
transporting direction. The object is transported rightwards in the
trough 7.
[0099] In the vibratory conveyor 2 of this embodiment, the linear
motor 26 is used as exciting source for driving the trough
horizontally. It can generate a driving force of an arbitrary form.
The object can be transported efficiently in the trough 7. The
change of the transporting direction and the transporting speed can
be adjusted easily without the complicating construction. Further,
no gear is used. Accordingly, little noise is made. Also in the
vibratory conveyor 2 of this embodiment, the reaction of the
primary member 28 of the linear motor 26 is not transmitted to the
mounting surface, since the secondary member 27 can be free moved
in the air.
[0100] Next, a vibratory conveyor 3 according to a third embodiment
of this invention will be described with reference to FIG. 14 to
16. The parts which correspond to the parts in above embodiments,
are denoted by the same reference numerals and the detailed
description of which will be omitted.
[0101] FIG. 14 and FIG. 15 show perspective and front views,
respectively. Plural support mechanism 31 as shown in FIG. 14 and
15 are used insteads of the supporters 21 in the above embodiment.
A linear motor 36 is used insteads of the linear motors 16 and 26.
Also in FIG. 14, the trough 7 is shown by the dot-dash lines to
clearly show support mechanism 31 and linear motor 36.
[0102] The support mechanism 31 of this embodiment, function as a
linear guide. It consists of a fixing part 32, balls 34 rotatably
held by a holding case 35 and a movable part 33 arranged slidably
through not-shown linear mechanism. U-shaped linear recesses are
formed in the bottom of the movable part 33. The balls 34 can be
rotated in the recess. Grease may be supplied to the recess so as
to easily rotate balls 34.
[0103] The linear motor 36 in this embodiment as shown enlargedly
in FIG. 16, consist of a primary member 38 fixed to the trough 7,
and a secondary member 37 supported through a plate-like
vibration-absorbing material 40 on the ground (not shown). The
primary member 38 is almost parallel-piped and the trough 7 is
fixed on the upper surface 38a. The coils 19a, 19b, 19c are wound
on the poles U, V, W having permanent magnets. The coils 19a, l9b,
19c are arranged in the lower potion of the primary member 38. A
groove 37a is formed in the secondary member 37. The primary member
38 can be slided; in the groove 37a. The cross section of the
secondary member is U-shaped. The plural teeth 37abare formed
between the groove 37a, and arranged vertically to the transporting
direction. An air gap s" is formed by not-shown wheel or linear
guide between the teeth 37ab and the primary member 38.
[0104] Constructions of the vibratory conveyor 3 have been
described. Next, operations will be described.
[0105] Similarly to the above embodiment, alternating currents
shifted in phase from each other by 120 degrees are flowed through
the coils 19a, 19b ,19c of the linear motor 36. The magnetic
attractive force is generated between the magnetic poles U, V, W
and the magnet teeth 37ab. Thus, the primary member 38 is moved
rightwards. The trough 7 fixed on the primary member 38 is also
moved rightwards. The secondary member 37 receive the reactive
force in opposite direction to the exciting force generated from
the first primary member 38 through the not-shown wheel of
non-magnetic material. The secondary member 37 is arranged through
the vibration-absorbing rubber 40 on the mounting surface.
Accordingly, the reactive force or reaction force received by the
secondary member 37 is absorbed by the vibration absorbing rubber
40.
[0106] The current is so controlled that the trough 7 is moved
slowly fowards and the object and the trough 7 are moved together.
The moved part 33 of the support mechanism 31 supporting the trough
7 is reciprocating as shown by the dot-dash lines in FIG. 15.
[0107] The reverse currents are supplied to the coils 19a, 19b, 19c
wound on the magnet poles U, V, W.
[0108] The trough 7 is moved leftwards. The secondary 10 member 37
receives a reaction force. It is absorbed by the
vibration-absorbing rubber 40. In this time, the exciting force
overcomes a stationary frictional force between the object and the
trough 7. The primary member 38 is moved backwards rapidly. The
current is so controlled as to obtain the rapid movement. The
moving part 33 of the support mechanism 31 supporting the trough 7
is reciprocated as shown by the dot-dash lines and two-dot-dash
lines. In the above operation, the object is transported rightwards
in the trough 7.
[0109] Also in the vibratory conveyor 3 of this embodiment, the
linear motor 36 is used as an exciting source for vibrating the
trough horizontally. Accordingly, an exciting force of an arbitrary
form can be obtained, and so the objects can be transported
efficiently in the trough7. The change-over of the transporting
direction andthe transporting speed can be easily adjusted without
complicated construction. No gear is used and so little noise is
made from the vibratory conveyor 3. The secondary member 37 of the
linear motor 36 for driving the vibratory conveyor 3 is arranged
through the vibration-absorbing rubber 40 on the mounting surface.
When the trough 7 is vibrated by the linear motor 36, the reaction
force of the secondary member 37 is not transmitted to the mounting
surface, since it is absorbed by the vibration-absorbing rubber
40.
[0110] FIG. 21 shows a vibratory conveyor according to a sixth
embodiment of this invention.
[0111] A vibratory conveyor of this embodiment is generally
represented by a reference mark V.
[0112] A trough 51 is longer than the trough 7 of the above
embodiments, and supported through plural support mechanism 52 at
regular intervals on the ground, which are similar to those 11 of
the first embodiment.
[0113] The linear motor means consists of plural linear motors
L.sub.1, L.sub.2, L.sub.3, . . . which are equivalent to the linear
motors of the first embodiment. Drive command is supplied to coils
C.sub.1, C.sub.2, C.sub.3. . . of primary members in the following
manner. Speed command (saw-tooth shapedly change) as the drive
command is supplied to a comparator P1 from a speed command source
A. A signal representing relative position of the primary member to
the secondary member from an encoder Em attached to the primary
member is supplied to a differentiater S.sub.1 and then a speed
signal there from is supplied to another input terminal of the
comparator P1. The speed command from the speed command source A
and actual speed are compared with the comparator Pl, and the
difference is amplified by an amplifier K.sub.1 having gain K1 and
the output is supplied to the coils C.sub.1 of the primary member.
Thus, the relative speed of the primary member to the secondary
member is so controlled as to be equal to the command.
[0114] The same speed command from the speed command source A is
supplied to a second comparator P2. A signal representing a
relative position of a primary member to a secondary member from
the encoder Em attached to the primary member of a second linear
motor L2 is supplied to a second differenciator S2. Thus, the speed
signal is supplied to another input terminal of the second
comparator P2. The difference is supplied to a second amplifier K2
having gain K2. The amplified output is supplied to the coils C2 of
the primary member of the linear motor L.sub.2. Thus,the speed
command is supplied to the first coil C1 of the first linear motor
L1 and the second coil C2 of the primary member of the second liner
motor L2 in synchronization with each other. In the above descrived
manner,the speed command is supplied to the first, second, third .
. . liner motors L.sub.1, L.sub.2, L.sub.3 . . . Although the
trough 51 is longer, it can be smoothly vibrated without
distortion, by the synchronized speed command, and the objects can
be smoothly transported rightwards in the trough 51.
[0115] FIG. 22 shows a vibratory conveyor according to a seventh
embodiment of this invention. Those which correspond to the parts
of the above described embodiment, are represented by the same
reference numerals and the detailed description of which will be
omitted.
[0116] A vibratory conveyor of this embodiment is generally
represented by a refernce mark W.
[0117] Also in this embodiment, the predetermined speed command is
supplied to the first comparator P.sub.1.Output of the encoder Em'
attached to the primary member is supplied to the first
differenciator S.sub.1. The differenciated output is supplied to
another input terminal of the first comparator P.sub.1. According
to this embodiment, a primary member including coils C10 is fixed
to the ground. Magnetic teeth 62a of a secondary member 62 are
facing to the primary member 61 with a small air gap, which is
exaggeratedly shown in FIG. 22. The encoder EM' detects a relative
position of the secondary member 62 to the first primary member 61.
The same speed command is supplied to the comparators P.sub.2,
P.sub.3 . . . of the linear motors L.sub.1, L.sub.2, L.sub.3,
L.sub.4. . .
[0118] The signal representing the relative the position of the
secondary member 62 of the primary member 61 is generated from the
encoder EM'. It is differentiated by the differentiator S.sub.1,
and t differentiated output is supplied to the first comparator
P.sub.1. The differece between the speed command and the actual
speed is amplified by the amplifier K.sub.1, and the output is
supplied to the coils C10 of the primary member 61 fixed on the
ground. Thus, the driving force corresponding to the speed command
is applied to the trough 51 and the trough is vibrated at the
predetermind speed (in saw tooth form). The speed command is
supplied also to a second comparator P.sub.2 from the speed
comparator source A. The signal representing the relative position
of the secondary member 62 to the primary member 61 is supplied to
a differentiater S.sub.2. It is differentiated thereby. The
difference between the speed command and the actual speed is
amplified by the amplifier K.sub.2 having gain K.sub.2. And it is
supplied to the coils C11, of the primary member 61. In the
simmilar manner, the same speed command is supplied to the linear
motors L1', L2', L3'. . . Although the trough 51 is long, it can be
smoothly vibrated, and the object can be smoothly conveyed in the
trough 51. Although not shown, the primary members 61 are supported
through vibration-absorbing materials on the ground. The long
trough 51 can vibrate without distortion, and so the object can be
smoothly transported.
[0119] FIG. 23 shows a vibratory conveyor 24 according to an eighth
embodiment of this invention. FIG. 24 is a cross-sectional view
taken along the line [XXIV]-[XXIV] in FIG. 23. A trough 41 is
supported by plural supporters 25 paired at both sides of the
trough 41. The trough 41 is excited by a linear motor 42. The
supporters 25 are used instead of the support mechanism 11 of the
first embodiment. Vertical plates 43 are fixed to the bottom of the
trough 41. Rollers 45 are supported by shafts 44 attached to the
vertical plates 43. The rollers or wheels 45 are guided by arcuate
guide rails 46 fixed on the ground. The guide surfaces for the
wheels 45 are arcuate. L-shaped portions 46a are formed for
regulating the movement of the wheels 45, integrally with the guide
rail 46. Thus, the trough 41 is prevented from shifting
laterelally.
[0120] The construction of the vibratory conveyor 24 operation is
described.
[0121] With the energization of the linear motor 42, the trough 41
is horizontally vibrated, while the wheels 45 are rolling along the
guide rails 46. The rolling surfaces of the guide rails 46 are
arcuate, and so the centering action is supplied to the wheels 45,
so that the trough 41 is urged to move back to the balancing
position or the neutral position. The secondary member 68 is
prevented from being shifted from the primary member 67 fixed on
the ground G through the rubbers 4, so that the desired thrust can
be surely obtained. Further, the supporters 25 can be arranged in
compact under the trough 41.
[0122] Next, a vibratory conveyor 53 according a ninth embodiment
of this invention will be described with reference to FIG. 25.
Those which correspond to the parts in the above embodiment, are
denoted by the same reference numerals and the detailed description
of which will be omitted.
[0123] In the vibratory conveyor 53, the trough 41 is supported by
supporters 54 at both sides of trough 41. The linear motor 42
excites the trough 41 in the horizontal direction. The arrangement
relationship between the wheels 45 and the guide rails 46 are
inverted in this embodiment. The guide rails 46 are fixed on the
bottom of the trough 41. The wheels 45 are rotatably supported by
vertical arms 43 on the ground G. The wheels 45 are guided by the
arcuate guides 46. Thus, similarly to the above embodiment, the
restoring or centering force is applied to the trough 41 and the
mounting space can be small for the supporters 32.
[0124] While the preferred embodiments have been described,
variations thereto will occur to those skilled in the art within
the scope of the present inventive concepts which are delineated by
the following claims.
[0125] For example, in the embodiment of FIG. 18, the secondary
member 57 may be supported through elastic material or
vibration-absorbing material on the ground, while the trough is
fixed on the upper surface of the primary member 58.
[0126] Further, in the linear motors 16 or 26, the additional
masses 30 or 30' is fixed through the fixing member 20 or 20' to
the primary member 18 or secondary member 27, so that the
acceleration of the primary member 18 or secondary member 27 is
reduced (the second law of motion), and the displacement of the
primary member 18 or secondary member 27 is reduced relative to the
displacement of the secondary member 17 or primary member 28.
However, when the mass of primary member 18 or of the secondary
member 27 is sufficiently large, the fixing members 20, 20' and the
additional mass 30, 30' can be omitted.
[0127] In the third embodiment, the member 37 of the linear motor
36 is supported though the plate-like rubber 40 as the elastic
material on the ground G. Sponge may be used instead of the rubber
40. Or the member 37 may be arranged on a plate supported by plural
coil springs which are mounted on the ground G.
[0128] Further in the above embodiments, the high-density type in
which the permanent magnets are used, is employed as the linear
motors 16, 26 and 36. Of course, a linear motor of the other type,
for example, the well-known linear induction motor or linear pulse
motor which is disclosed for example, in the Japanese patent
No.1495069, may be used.
[0129] Further, in the above embodiments, the supporter 11 of the
first embodiment includes the link mechanism, the supporter 3' of
the second embodiment includes the pendulum mechanism and the
supporter 31 of the third embodiment includes the linear guide. Of
course a supporter of the other type may be used. For example, the
supporter which is disclosed in the Japanese Patent Opening
Gazzette No. 315546/1997, may be used.
[0130] Further, in the sixth and seventh embodiments, the relative
position of the primary or secondary member to the secondary or
primary member is detected by the encoder EM'. The detector is not
limited to the encoder. For example, optical means or magnetic
means may be used instead of the encoder.
[0131] Further, in the sixth and seventh embodiments, the
predetermined speed command is supplied to the linear motor
L.sub.1, L.sub.2, L.sub.3 . . . from the speed command supply
source A. A position command or acceleration command may be used as
a drive command.
[0132] Further, in the embodiments of FIG. 6 to FIG. 18, a drive
command may be applied to the linear motor, while it has not been
described.
[0133] Further in the eighth and ninth embodiments, the guiding
surface of the guide block 46 is in the form of a part of circle.
However, it may be in the form of a part of ellipsoid.
* * * * *