U.S. patent application number 16/131602 was filed with the patent office on 2019-10-03 for fluid-controlled wire tension mechanism.
The applicant listed for this patent is National Taiwan Normal University. Invention is credited to Yen-Chia Chang, Shun-Tong Chen, Ying-Dan Chen, Jia-Jin Zhong.
Application Number | 20190300324 16/131602 |
Document ID | / |
Family ID | 65432003 |
Filed Date | 2019-10-03 |
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United States Patent
Application |
20190300324 |
Kind Code |
A1 |
Chen; Shun-Tong ; et
al. |
October 3, 2019 |
FLUID-CONTROLLED WIRE TENSION MECHANISM
Abstract
The present invention relates to a fluid-controlled wire tension
mechanism including a sealed container, a control valve, and a
delivery spool. The sealed container has a space. The control valve
is coupled to the sealed container to control fluid pressure in the
space. The delivery spool is coupled to the sealed container with a
compression end and a reel. The compression end is placed in the
space, and the reel is located outside the sealed container to send
out a cutting wire. Wherein, a fluid enters the space and applies
pressure on the compression end. The present invention utilizes the
fluid pressure to produce the rotating impedance to the delivery
spool, so that the component is wear-proof, the line tension is
easily controlled and the stream of the cutting wire can be stable
for a long time. Therefore, the cutting effect and the shape are
more precise.
Inventors: |
Chen; Shun-Tong; (Taipei
City, TW) ; Chen; Ying-Dan; (Taipei City, TW)
; Zhong; Jia-Jin; (Taipei City, TW) ; Chang;
Yen-Chia; (Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
National Taiwan Normal University |
Taipei City |
|
TW |
|
|
Family ID: |
65432003 |
Appl. No.: |
16/131602 |
Filed: |
September 14, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65H 2701/36 20130101;
B65H 59/04 20130101; B65H 59/381 20130101; B65H 2406/00 20130101;
B65H 59/38 20130101 |
International
Class: |
B65H 59/04 20060101
B65H059/04; B65H 59/38 20060101 B65H059/38 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 30, 2018 |
TW |
107111264 |
Claims
1. A fluid-controlled wire tension mechanism, adapted to control a
tension of a cutting wire by adjusting a fluid pressure generated
by a fluid, comprising: a sealed container, having a space for
containing the fluid; a control valve, coupled to the sealed
container to adjust the fluid pressure in the space; and a delivery
spool, coupled to the sealed container, the delivery spool having a
compression end and a reel, the compression end being configured in
the space and linked with the reel, and the reel being configured
outside of the sealed container to send the cutting wire; wherein
the tension of the cutting wire is controlled by a fluid damping
force corresponding to the fluid pressure applied to the
compression end.
2. The fluid-controlled wire tension mechanism of claim 1, wherein
the fluid is liquid or gas, and the cutting wire is a metal
wire.
3. The fluid-controlled wire tension mechanism of claim 1, further
comprising a disk configured on the compression end of the delivery
spool to bear the fluid pressure.
4. The fluid-controlled wire tension mechanism of claim 1, further
comprising a collecting spool configured to receive the cutting
wire, wherein delivery spool is configured to control the tension
of the cutting wire, and the collecting spool is configured to
control a move speed of the cutting wire.
5. The fluid-controlled wire tension mechanism of claim 1, wherein
the cutting wire is wound on the reel, and the reel is detachably
coupled to the compression end.
6. The fluid-controlled wire tension mechanism of claim 1, wherein
the sealed container further comprises a diversion hole, and the
fluid flows into the space via the diversion hole.
7. The fluid-controlled wire tension mechanism of claim 6, wherein
the sealed container further comprises an O-ring, a sealing cap and
a sealing housing, the sealing housing has the diversion hole; the
sealing cap and the sealing housing are sealed by the O-ring to
form the space.
8. The fluid-controlled wire tension mechanism of claim 7, wherein
the sealed container further comprises a bearing, and the delivery
spool is coupled to the sealing cap by the bearing.
9. The fluid-controlled wire tension mechanism of claim 1, further
comprising a plurality of delivery spools, wherein the plurality of
delivery spools are parallel to each other to form a array, and
each of the plurality of delivery spools sends a corresponding
cutting wire and controls the tension of the corresponding cutting
wire.
10. The fluid-controlled wire tension mechanism of claim 1, wherein
the control valve is configured to control a total amount of the
fluid in the space, an inflow rate of the fluid into the space, an
inflow pressure of the fluid into the space, or a volume of the
space.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority benefit of Taiwan
Application Serial No. 107111264 filed Mar. 30, 2018 the disclosure
of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a wire tension control
mechanism, and more particularly, to a non-contact wire tension
control mechanism which controls the wire tension by adjusting the
fluid pressure.
Description of the Prior
[0003] In recent years, with advances in technologies such as
semiconductor, electronic industry, and machinery, most products
have been developed to be small and refined. In particular,
products in semiconductor industry, display industry, digital
content industry and biotechnology industry are all developed
toward miniaturization. Industry is in great demand for light,
thin, short, and small components such as precision molds,
fixtures, cutters, tools, jigs, and probes. The materials used for
manufacturing also tend to be selected as hard-to-cut materials,
such as tungsten, conductive ceramics, boron-doped polycrystalline
composite diamonds, and boron-doped monocrystalline diamonds. All
the above requirements can be solved by wire electrical discharge
machining (WEDM). That is to say, there is a large market in WEDM
field.
[0004] In WEDM technology, the wire tension control is one of the
important parameters. The wire tension not only affects the details
of the cutting structure and the precision of the machining, but
also affects whether the wire electrode is broken. In practice,
most of the wire electrodes are used with wheel brake system to
control the wire tension. However, it is difficult for the wheel
brake system to make little adjustment and control. In addition,
since the electrical discharge wire electrode needs to be directly
contacted with the wheel brake system, the tension of the wire
electrode is difficult to be stably controlled due to the influence
of the dynamic material friction coefficient.
[0005] A non-contact control method uses a permanent magnet instead
of the wheel brake system used in the contact control method. The
wire tension is controlled by adjusting the distance between the
permanent magnet and the wire electrode spool. However, the
adjustment range of the distance is limited, and the wire tension
cannot be accurately controlled. Furthermore, if there are multiple
wire electrodes needed to be simultaneously operated for
high-efficiency cutting, it is difficult to adjust a plurality of
wire tensions of the wire electrodes arranging in an array.
Additionally, the hysteresis phenomena may occur to make the wire
flow unstable when the wire tension is controlled by the permanent
magnet.
[0006] Therefore, a new tension control system is needed to replace
the tension control system which has a wheel brake system or a
permanent magnet.
SUMMARY OF THE INVENTION
[0007] In response to the above-mentioned problems, the present
invention provides a fluid-controlled wire tension mechanism that
applies pressure on a delivery spool to generate a rotational
resistant on the delivery spool, wherein the delivery spool is
configured to send the cutting wire. Under the fixed wire receiving
speed conditions, the appropriate tension of the cutting wire can
be obtained by controlling the magnitude of the pressure that the
fluid applied on the delivery spool.
[0008] The present invention provides a fluid-controlled wire
tension mechanism to control a tension of a cutting wire by
adjusting a fluid pressure generated by a fluid. The
fluid-controlled wire tension mechanism comprises a sealed
container, a control valve, and a delivery spool. The sealed
container has a space for containing the fluid. The control valve
is coupled to the sealed container to adjust the fluid pressure in
the space. The delivery spool is coupled to the sealed container,
wherein the delivery spool has a compression end and a reel. The
compression end is configured in the space and linked with the
reel, and the reel is configured outside of the sealed container to
send the cutting wire. Wherein the tension of the cutting wire is
controlled by a fluid damping force corresponding to the fluid
pressure applied to the compression end.
[0009] In an embodiment, the fluid is liquid or gas, and the
cutting wire is a metal wire.
[0010] Additionally, the reel is coupled to the cutting wire and
linked with the compression end for coupling or winding the cutting
wire.
[0011] Furthermore, the reel is detachably coupled to the
compression end.
[0012] In an embodiment, the sealed container further comprises a
diversion hole, a bearing, a sealing cap, an O-ring and a sealing
housing. The sealing cap has the diversion hole, and the diversion
hole is used to make the fluid to flow into the space. The sealing
cap and the sealing housing are sealed by the O-ring to form the
space, and the delivery spool is coupled to the sealing cap by the
bearing.
[0013] In one embodiment, the fluid-controlled wire tension
mechanism further comprises a disk, and the disk is configured on
the compression end of the delivery spool to bear the fluid
pressure.
[0014] Besides, the fluid-controlled wire tension mechanism further
comprises a collecting spool configured to receive the cutting wire
which the reel of the delivery spool sends.
[0015] In addition, the delivery spool is configured to control the
tension of the cutting wire, and the collecting spool is configured
to control a move speed of the cutting wire.
[0016] In an embodiment, the fluid-controlled wire tension
mechanism further comprises a plurality of delivery spools. The
plurality of delivery spools are parallel to each other to form an
array, and each of the plurality of delivery spools sends a
corresponding cutting wire and controls the tension of the
corresponding cutting wire.
[0017] Wherein, the control valve is configured to control a total
amount of the fluid in the space, an inflow rate of the fluid into
the space, an inflow pressure of the fluid into the space, or a
volume of the space.
[0018] As mentioned above, the present invention utilizes a fluid
to apply pressure on a delivery spool to generate a rotational
resistant on the delivery spool, wherein the delivery spool is
configured to send a cutting wire. Under the constant receive rate
of the collecting spool, the delivery spool is bearing a fluid
damping force whose direction is opposite to the wire sending
direction. The damping effect on the delivery spool is more
pronounced while the fluid pressure increases. Therefore, as the
fluid pressure increases, the tension of the cutting wire will
become larger, and the cutting wire will also be straighter. Since
the fluid pressure does not directly act on the cutting wire, the
cutting wire can be maintained in a stable flow, and the tension of
the cutting wire can be easily grasped and controlled. Because the
fluid-controlled wire tension mechanism of the present invention
does not use the friction of the solid contact to generate
resistance, the component of the wire tension control mechanism is
less prone to wear. Therefore, the fluid-controlled wire tension
mechanism of the present invention can maintain stable transmission
of the cutting wire for a long time, and the cutting shape can be
also more precise.
BRIEF DESCRIPTION OF THE APPENDED DRAWINGS
[0019] Some of the embodiments will be described in detail, with
reference to the following figures, wherein like designations
denote like members, wherein:
[0020] FIG. 1 shows a perspective view of one embodiment of the
fluid-controlled wire tension mechanism in the present
invention.
[0021] FIG. 2 shows a schematic view of one embodiment of the
fluid-controlled wire tension mechanism in the present
invention.
[0022] FIG. 3 shows a schematic view of one embodiment of the
delivery spool in the present invention.
[0023] FIG. 4 shows another view of the schematic view of one
embodiment of the delivery spool in the present invention.
[0024] FIG. 5A shows a schematic view of the compression end as
viewed from the end away from the drive shaft.
[0025] FIG. 5B shows a schematic view of the compression end as
viewed from the end close to the drive shaft.
[0026] FIG. 6 shows a schematic view of another embodiment of the
fluid-controlled wire tension mechanism in the present
invention.
[0027] The advantages, spirits, and features of the present
invention will be explained and discussed with embodiments and
figures as follows.
DETAILED DESCRIPTION OF THE INVENTION
[0028] A detailed description of the hereinafter described
embodiments of the disclosed apparatus and method are presented
herein by way of exemplification and not limitation with reference
to the Figures. Although certain embodiments are shown and
described in detail, it should be understood that various changes
and modifications can be made without departing from the scope of
the appended claims. The scope of the present invention will in no
way be limited to the number of constituting components, the
materials thereof, the shapes thereof, the relative arrangement
thereof, etc., and are disclosed simply as an example of
embodiments of the present invention.
[0029] In the description of the present specification, the
terminologies "in an embodiment", "in another embodiment", or "in
some embodiments" mean that the specific feature, structure,
material or characteristic of the present embodiment is involved in
at least one embodiment of the present invention. In the
description of the present specification, the schematic
representation of the mentioned terminologies does not necessarily
refer to the same embodiment. Furthermore, the described specific
feature, structure, material or characteristic can be involved in
any one or more embodiments in a proper way.
[0030] In the embodiments of the present specification, the
terminology "or" includes the combination of part of the listed
components, and the combination of all the listed components. For
example, the described "A or B" includes only A, only B, and both A
and B. Moreover, the terminologies "a" and "the" before the element
or component of the present invention do not limit the number of
elements or components. Therefore, the terminologies "a" and "the"
should be read as "including one" or "at least one". Besides, the
singular form of the elements or components also includes the
plural form, unless the number clearly refers to the singular
form.
[0031] Please refer to FIG. 1 and FIG. 2. FIG. 1 shows a
perspective view of one embodiment of the fluid-controlled wire
tension mechanism 1 in the present invention. FIG. 2 shows a
schematic view of one embodiment of the fluid-controlled wire
tension mechanism 1 in the present invention. The fluid-controlled
wire tension mechanism 1 in the present invention is used to
control a tension of the cutting wire 6 by adjusting a fluid
pressure generated by a fluid. The fluid-controlled wire tension
mechanism 1 comprises a sealed container 10, a control valve 15,
and a delivery spool 11. The sealed container 10 has a space 100
for containing the fluid. The control valve 15 is coupled to the
sealed container 10 to adjust the fluid pressure in the space 100.
The delivery spool 11 is coupled to the sealed container 10,
wherein the delivery spool 11 has a compression end 110 and a reel
116. The compression end 110 is configured in the space 100 and
linked with the reel 116, and the reel 116 is configured outside of
the sealed container 10 to send the cutting wire 6. Wherein the
tension of the cutting wire 6 is controlled by a fluid damping
force corresponding to the fluid pressure applied to the
compression end 110.
[0032] The fluid pressure in the space 100 will be generated after
the fluid enters the space 100. At that time, the compression end
110 in the space 100 will bear the fluid pressure. When the reel
116 rotates for sending the cutting line 6, the compression end 110
will be rotated in synchronization. In addition, the compression
end 110 will be affected by a rotational resistant generated by the
fluid pressure when the compression end 110 rotates, which will
take the other end of the delivery spool 11, such as the reel 116,
to slow down the rotational speed. Therefore, a pulling force is
generated, wherein the direction of the pulling force is opposite
to the direction of sending cutting wire 6. Finally, since the
moving speed of the cutting wire 6 does not change, the tension of
the cutting wire 6 becomes large.
[0033] The fluid pressure and the rotational resistance applied on
the compression end 110 will become larger when the control value
15 is adjusted to increase the fluid pressure in the space 100,
which will apply a stronger pulling force on the reel, thereby
increasing the tension of the cutting wire 6. Oppositely, the
tension of the cutting wire will be reduced when the control value
15 reduces the fluid pressure in the space 100. In one embodiment,
the control value 15 controls the fluid pressure in the space 100
by keeping the fluid entering the space. In this case, the sealed
container 10 may have a fluid outlet for the fluid to flow out,
thereby adjusting the fluid pressure in the sealed container,
wherein the fluid outlet may also have an adjustment function. In
another embodiment, the control value 15 increases the pressure in
the space 100 via a pressurizing device.
[0034] However, the present invention is not limited thereto,
wherein the purpose of the control valve 15 is to control the fluid
pressure in the space 100. The control valve 15 is capable of
achieving this purpose, for example, controlling the total amount
of the fluid in the space, controlling the inflow rate when the
fluid enters the space, controlling the inflow pressure when the
fluid enters the space, controlling the volume in the space, or
achieving more than one of above various functions at the same
time, which is all within the scope of the present invention.
[0035] In one embodiment, the fluid is liquid, gel, or gas, and the
cutting wire 6 is a metal wire. The liquid can be water. Solid or
gaseous substances may also be added to the liquid to increase or
decrease the fluid damping constant. The solid substances can be
selected as sand or dust. The gel state fluid can be paste. The gas
can be air, and the metal wire can be a common wire used in cutting
process, such as copper wire or zinc wire.
[0036] Addition, the reel 116 can be regarded as a wire bobbin
wound with a sufficient amount of metal wire, whereby the cutting
wire 6 used for processing is all derived from the reel 116.
Furthermore, the reel 116 is detachably coupled to the compression
end 110. When the reel 116 sends out all the cutting wire 6
thereon, the reel 116 can be removed to replace a new reel 116.
Alternatively, a wire feeding device cooperates with the reel 116,
and a metal wire sent by the wire feeding device is attached or
wound on the reel 116. Therefore, the delivery spool 11 can be
regarded as an element which sends the metal wire and generates a
resistant by the fluid pressure.
[0037] In one embodiment, the sealed container 10 further comprises
a diversion hole 106 and a sealing cap 107. The diversion hole 106
is used to make the fluid to flow into the space. In one
embodiment, the control valve 15 is coupled to the diversion hole
106 or configured outside of sealed container and corresponding to
the diversion hole 106, wherein the control valve 15 can easily
control the inflow rate of the fluid into the sealed container 10
and the fluid pressure in the sealed container 10. In another
embodiment, a valve is external coupled to the diversion hole 106
to adjust the amount of the fluid into and out of the sealed
container 10, and the control valve 15 is used to control the fluid
pressure in the sealed container 10.
[0038] Additionally, the sealed container 10 includes a bearing
103, and the delivery spool 11 is coupled to the sealing cap 107 by
the bearing 103. The reel 116 and the compression end 110 are
respectively located on both sides separated by the sealing cap 107
and the bearing 103; therefore, the reel 116 located outside of the
sealed container 10 will not directly bear the fluid pressure in
the sealed container 10. Further, since the reel 116 is located
outside of the sealed container 10, the reel 116 can be easily
replaced, and the cutting wire wound on the reel 116 also can be
replaced directly. Moreover, the sealed container 10 includes an
oil seal 104. The oil seal 104 couples to the sealed cap 107 and
surrounds the delivery spool 11. The oil seal 104 is served to
prevent fluid from entering or escaping the space 100 via the joint
between the delivery spool 11, the bearing 103, and sealed cap
107.
[0039] In addition, the sealed container 10 further comprises an
O-ring 109 and a sealing housing 108. The sealing housing 108 has a
diversion hole 106, and the sealing cap 107 and the sealing housing
108 are sealed by the O-ring 109 to form the space 100. The sealing
cap 107 and the sealing housing 108 can be detachably coupled, so
that the component of the compression end 100 in the space 100 can
be easily replaced. Furthermore, since the sealing cap 107 is
detachably coupled to the sealing housing 108, other components can
be added in the sealing housing 108, and also can be replaced with
the sealing housing 108 of different capacities to create different
geometries of the space. In an embodiment, the geometric size of
the space 100 also can be controlled by the control valve 15.
Besides, the whole or any part of the control valve 15 may be
located in the space 100 to adjust the geometric size of the space
100.
[0040] Please refer to FIG. 3, FIG. 4, FIG. 5A and FIG. 5B. FIG. 3
shows a schematic view of one embodiment of the delivery spool 11
in the present invention. FIG. 4 shows another view of the
schematic view of one embodiment of the delivery spool 11 in the
present invention. FIG. 5A shows a schematic view of the
compression end 110 as viewed from the end away from the drive
shaft 111. FIG. 5B shows a schematic view of the compression end
110 as viewed from the end close to the drive shaft 111. In one
embodiment, the compression end 110 is formed as a disk shape. But
in another embodiment, the fluid-controlled wire tension mechanism
1 further comprises a disk configured on the compression end 110 of
the delivery spool 11, wherein the disk is configured to bear the
fluid pressure. The area of the disk larger causes the damping
force applied on the disk larger. The compression end 110 of the
delivery spool 11 is connected and linked with the reel 116 by a
drive shaft 111.
[0041] In another embodiment, the compression end 110 is configured
with the non-disk shape object, such as another shaped object, an
object with blade, or an object with rough surface.
[0042] The compression end 110 in FIG. 5A and FIG. 5B can be a
compression end 110 with a disk shape, or a compression end 110
configured with a disk. The total surface area of the compression
end 110 should be known before calculating the fluid damping force.
In the case of which the diameters of both sides of the disk are
the same and the thickness is uniform, the first area A1 is the
area of the first surface of the disk, and the second area A2 is
the area exposed by the second surface of the disk corresponding to
the first surface. The third area A3 is a side surface area of the
disk. The total surface area A is the sum of the first area A1, the
second area A2, and the third area A3. The first area A1 is
.pi..times.R.sub.s1.sup.2 in FIG. 5A, and the second area A2
covered by the oblique line is
.pi..times.(R.sub.s1.sup.2-R.sub.s2.sup.2) in FIG. 5B. Therefore,
the total surface area which contacts the fluid is
A=.pi.(2R.sub.s1.sup.2-R.sub.s2.sup.2)+2.pi.R.sub.s1t.sub.s
[0043] Wherein, A is the total surface area (mm.sup.2) of the
compression end 110, R.sub.s1 is the disk radius (mm) of the
compression end 110, R.sub.s2 is the shaft radius (mm) of the drive
shaft 111, and is t.sub.s the thickness (mm) of the disk of the
compression end 110. In another embodiment, the surface of the
portion drive shaft in the space 100 must also be added to the
total surface area A.
[0044] Then calculating the fluid damping force applied on the disk
according to the total surface area A. The formula is as
follows:
F.sub.d=.mu..times.P.times.A
[0045] Wherein, F.sub.d is the fluid damping force (N), .mu. is the
fluid damping constant, and P is the fluid pressure (MPa).
[0046] A pulling force applied on the cutting wire 6 is generated
by the fluid damping force, that is, the fluid damping force
generates a force applied on the reel 116 whose direction is
opposite to the wire sending direction. The greater fluid pressure,
the greater fluid damping force is generated. At that time, the
torque generated by the radius and the wire tension of the reel 116
is equal to the torque generated by the radius of the delivery
spool 11 and the damping force, as shown in the following
formula:
F.sub.d.times.R.sub.s1=(T.sub.w-F.sub.f).times.R.sub.b
[0047] Wherein, F.sub.d is the fluid damping force (N) calculated
above, T.sub.w is the tension of the cutting wire 6, F.sub.f is the
bearing rotational friction force of the fluid-controlled wire
tension mechanism 1, and R.sub.b is radius of the reel 116.
Therefore, the tension of the cutting wire can be calculated by the
known fluid damping force, the radius of the disk of the
compression end 110, the radius of the coil portion 116, and the
friction force of the fluid-controlled wire tension mechanism
1.
[0048] Please refer to FIG. 1 and FIG. 6. FIG. 6 shows a schematic
view of another embodiment of the fluid-controlled wire tension
mechanism in the present invention. In one embodiment, the
fluid-controlled wire tension mechanism 1 further comprises a
collecting spool 16 configured to receive the cutting wire 6 sent
from the reel 116 of the delivery spool 11. Wherein, the delivery
spool 11 is configured to control the tension of the cutting wire
6, and the collecting spool 16 is configured to control a move
speed of the cutting wire 6.
[0049] In one embodiment, the fluid-controlled wire tension
mechanism 1 further comprises a plurality of delivery spools 11.
The plurality of delivery spools 11 are parallel to each other to
form an array, and each of the plurality of delivery spools 11
sends a corresponding cutting wire 6 and controls the tension of
the corresponding cutting wire 6, wherein there are a plurality of
collecting spools 16 for receiving the corresponding cutting wire
6. Further, since the plurality of delivery spools 11 are coupled
to a single sealed container 10, the sufficient fluid damping force
can be applied on each delivery spool without external amount or
pressure of the fluid. Therefore, the present invention can achieve
the effect of reducing energy consumption. In another embodiment,
one collecting spool 16 can be used to receive a plurality of
cutting wire sent from the plurality of delivery spools 11.
[0050] In one embodiment, if each cutting wire 6 has different
tension requirements, the disks with different areas can be
configured on the corresponding compression end 110 respectively,
or the compression end 110 can be directly replaced with different
geometries, thereby achieving the effect of different wire tension
formed by a single control valve.
[0051] Compare to the prior art, the present invention utilizes a
fluid to apply pressure on a delivery spool to generate a
rotational resistant on the delivery spool, wherein the delivery
spool is configured to send a cutting wire. Under the constant
receive rate of the collecting spool, the delivery spool is bearing
a fluid damping force whose direction opposite to the wire sending
direction. The damping effect on the delivery spool is more
pronounced while the fluid pressure increases. Therefore, as the
fluid pressure increases, the tension of the cutting wire will
become larger, and the cutting wire will also be straighter. Since
the fluid pressure does not directly act on the cutting wire, the
cutting wire can be maintained in a stable flow, and the tension of
the cutting wire can be easily grasped and controlled. Because the
fluid-controlled wire tension mechanism of the present invention
does not use the friction of the solid contact to generate
resistance, the component of the wire tension control mechanism is
less prone to wear. Therefore, the fluid-controlled wire tension
mechanism of the present invention can maintain stable transmission
of the cutting wire for a long time, and the cutting shape is also
more precise.
[0052] With the examples and explanations mentioned above, the
features and spirits of the invention are hopefully well described.
More importantly, the present invention is not limited to the
embodiment described herein. Those skilled in the art will readily
observe that numerous modifications and alterations of the device
may be made while retaining the teachings of the invention.
Accordingly, the above disclosure should be construed as limited
only by the metes and bounds of the appended claims.
* * * * *