KR101577213B1 - Multi direction changeover valve - Google Patents

Abstract

The present invention relates to a multi-directional switching valve comprising a valve housing formed with a hollow pipe structure and having a plurality of ports for discharging cooling water supplied to the central space to respective external cooling elements, A valve unit installed at one end of the valve housing to interlock with the cam in accordance with rotation of the drive shaft to open and close the port, A multi-directional switching valve characterized by comprising a drive unit for providing a rotational force to a shaft.

Description

Multi-Directional Changeover Valve {MULTI DIRECTION CHANGEOVER VALVE}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a multi-directional switching valve, and more particularly, to a multi-directional switching valve capable of opening and closing a plurality of ports individually on one axis to control the flow of fluid.

Generally, the vehicle prevents the engine from being sub-cooled or overheated by the cooling water, which is heated by the engine or cooled by the radiator, thereby controlling the engine temperature to obtain the best engine output.

To this end, a multi-directional switching valve is used to control the flow of cooling water to the vehicle. That is, the multi-directional switching valve adjusts the flow rate of the cooling water supplied to the engine, the radiator, etc. to optimize the flow rate of the engine cooling system, thereby shortening the warm-up time and minimizing the frictional loss of the engine. Prior art of such a multi-way selector valve is the multi-way selector valve of Korean Patent No. 10-1210208 filed by the present applicant.

The multi-directional switching valve according to the prior art is composed of a housing, a spool, and a driving unit. The housing has a shape of a shielded cylinder, and a hole through which the fluid communicates is formed in rows and columns along the outer peripheral surface, An upper space and a lower space, and an inner space in which fluid is communicated is provided.

Further, the spool is provided with a plate-like member for shielding the inner middle portion of the housing, and divides the upper and lower holes, and rotates inside the housing to open and close the upper and lower holes. The driving unit is connected to the spool to provide power for rotating the spool.

However, since the multi-way switching valve according to the prior art having the above-described structure has a structure in which the upper and lower holes of the housing are divided by the spool installed in the housing, the multi- And has a structure that flows along a predetermined flow path according to the rotation of the spool after the fluid is introduced. Therefore, there is a limit to control so that a single fluid flows into the housing and then supplied in various directions according to the state of the vehicle.

Further, according to the prior art, since the spool rotates inside the housing by the driving unit and has a structure for controlling the flow of the flow path, when the spool is operated for a long time, wear occurs between the outer peripheral surface of the spool and the inner peripheral surface of the housing, There is a concern.

Particularly, since the multi-directional switching valve according to the prior art has a structure in which the outer circumferential surface of the spool rotates in contact with the inner circumferential surface of the housing at all times, the contact area between the spool and the housing is excessively increased, The risk of occurrence of a gap between the housing and the housing increases.

When the gap is formed between the spool and the housing due to the wear, the flow of the fluid can not be precisely controlled due to disturbance of the fluid flowing through the gap unintentionally through the gap, have.

In addition, the prior art in which the flow of the fluid is controlled in accordance with the rotation of the spool as described above has a problem that it is difficult to apply a separate sealing structure to the plurality of upper and lower holes formed in the housing in which the fluid communicates.

KR 10-1210208 B (2012.12.03)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multi-directional switching valve capable of individually controlling a plurality of ports through which a fluid communicates, thereby precisely controlling the flow of the fluid.

Another object of the present invention is to provide a multi-directional switching valve that minimizes a contact area between a port through which a fluid is communicated and a valve body that opens and closes, thereby preventing leakage due to wear of parts.

Another object of the present invention is to provide a multi-directional switching valve capable of preventing undesired fluid leakage by generating pressure so that the port and the valve body are in intimate contact with each other.

According to an aspect of the present invention, there is provided a refrigerator comprising: a valve housing formed with a hollow pipe structure and having a plurality of ports for discharging cooling water supplied to the central space to respective cooling elements; A drive shaft provided in a central space of the valve housing and formed with cams corresponding to the ports on the outer surface thereof; a valve unit interlocked with the cam in accordance with rotation of the drive shaft to open and close the port, And a driving unit installed on the driving shaft to provide rotational force to the driving shaft.

The valve housing includes a housing supporter formed at the other end of the valve housing and having cooling water introduced thereinto and bearing the other end of the driving shaft, a seat formed at one end of the valve housing facing the housing supporter, And a cover provided with a connector for closing the seat portion and supplying electric energy to the drive unit.

The valve unit includes a cylinder supported by the valve housing and positioned between the cam and the port, a piston installed in the cylinder and linearly moving, and a piston installed at a base end of the piston, A rod that is provided at the tip of the rod and opens and closes the port in accordance with the rotation of the cam, and a rod provided inside the cylinder, And a first elastic member for providing an elastic force to be brought into close contact with the cam.

The valve unit includes a cylinder supported by the valve housing and positioned between the cam and the port, a piston installed in the cylinder and moving linearly, a part of the piston is embedded in the base end of the piston, A rod which is provided at the tip of the rod and which opens and closes the port in accordance with the rotation of the cam; And a first elastic member installed to provide an elastic force such that the rolling ball is in close contact with the cam.

At this time, it is preferable that the pusher is provided with a sealing member around its outer surface.

The valve unit may further include a second elastic member interposed between the outer end of the cylinder and the pusher so that the pusher applies pressure to the port when the pusher closes the port.

Preferably, the rod penetrates through the pusher and protrudes forward of the port, and a snap ring is provided at the tip of the rod to fix the pusher.

The driving unit includes a pinion provided on a rotating shaft of the driving motor, a screw rotating in conjunction with the pinion, a worm gear rotating in engagement with the screw and axially coupled with the cam shaft, and the drive motor, And the drive unit is mounted to the seat portion of the valve housing in a state where the drive motor, the pinion, the screw, and the worm gear are assembled to the bracket.

According to the multi-directional switching valve according to the present invention, the plurality of ports formed in the valve housing can be opened or closed by one drive shaft, so that the power transmission system for operating the valve unit is simplified, So that the flow of the cooling water can be precisely controlled.

In addition, since the valve unit that converts the rotation of the cam formed in the drive shaft into linear motion and the valve unit that opens and closes the port moves with the cam and rolls, the wear of the parts can be minimized, Thereby increasing the lifetime of the battery.

In addition, the drive unit that provides the rotational force to the drive shaft is modularized into a semi-assembled state, so that the drive unit can be installed quickly and easily on the seat, thereby improving the productivity of the product.

1 is a perspective view showing a multi-directional switching valve according to the present invention.
2 is an exploded perspective view showing a multi-directional switching valve according to the present invention.
3 is a cross-sectional view showing a multi-directional switching valve according to the present invention.
4 is a perspective view showing a valve unit and a driving unit of the multi-directional switching valve according to the present invention.
5 is a cross-sectional view showing the structure of a valve unit among the multi-directional change-over valves according to the present invention.
6 is a cross-sectional view showing an operating state of the valve unit of the multi-directional switching valve according to the present invention.
7 is an exploded perspective view showing a driving unit of the multi-directional switching valve according to the present invention.
8 is a cross-sectional view showing another embodiment of the valve unit of the multi-directional switching valve according to the present invention.
9 is a cross-sectional view showing another embodiment of the valve unit of the multi-directional switching valve according to the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and the inventor may properly define the concept of the term to describe its invention in the best possible way And should be construed in accordance with the principles and meanings and concepts consistent with the technical idea of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a multi-directional switching valve according to the present invention, FIG. 2 is an exploded perspective view showing a multi-directional switching valve according to the present invention, and FIG. 3 is a sectional view showing a multi-directional switching valve according to the present invention.

The multi-directional switch valve according to the present invention includes a valve housing 100 having a plurality of ports 150 formed thereon and a cam 210 corresponding to a port 150 formed in the valve housing 100 A valve unit 300 that opens and closes the port 150 in cooperation with the cam 210 in accordance with the rotation of the driving shaft 200 and a driving unit 400 that provides rotational force to the driving shaft 200, .

In detail, the valve housing 100 is formed in a hollow pipe structure, and a plurality of ports 150 for discharging the cooling water supplied to the central space to each external cooling element are formed.

The valve housing 100 includes a housing supporter 110 into which cooling water flows and which supports the driving shaft 200, a seating portion 120 on which the driving unit 400 is mounted, a cover 130 that closes the seating portion 120, ).

The housing supporter 110 is formed at the other end of the valve housing 100. As shown in Fig. 2, the housing supporter 110 has a shape of a hollow disk having an outer diameter closely contacting the inner diameter of the other end of the valve housing 100 A support hole 114 is formed at the center of the drive shaft 200 to support the other end of the drive shaft 200 and a rib 116 is formed radially around the support hole 114.

When the rib 116 is radially formed around the support hole 114, a void space between the rib 116 and the rib 116 is formed to form the inflow hole 112 through which the cooling water flows. A stopper (not shown) for limiting the rotation angle of the drive shaft 200 is formed in the support hole 114 that supports the other end of the drive shaft 200 so that the drive shaft 200 is coupled to the drive unit 400 When the rotation is made by the rotation force provided from the rotation angle sensor (not shown).

That is, the drive motor 410 of the drive unit 400 that provides the rotational force to the drive shaft 200 is constituted by a stepping motor that rotates in the forward and reverse directions, so that the drive shaft 200 does not rotate beyond 360 degrees, The stopper formed in the support hole 114 restricts the rotation of the drive shaft 200 beyond a certain range, for example.

The seating part 120 is formed at one end of the valve housing 100 facing the housing supporter 110 formed at the other end of the valve housing 100 and is mounted with the driving unit 400. 2 or 7, the seat unit 120 includes a drive unit 400 having a shape of a box whose one side is open at one end of the valve housing 100 and which provides rotational force to the drive shaft 200 Respectively.

At this time, the seating part 120 is formed with the same through hole 122 as the axis of the valve housing 100 so that when the driving shaft 200 is positioned in the valve housing 100, one end of the driving shaft 200 is seated Through the through hole 122 of the unit 120 and is axially coupled to the drive unit 400. [ At this time, a bearing member such as a bearing (not shown) is installed in the through hole 122 of the seating part 120 to support the driving shaft 200 so as to rotate smoothly when the driving shaft 200 rotates.

The cover 130 closes the seating part 120 opened at one side to protect the driving unit 400 mounted on the seating part 120 from being exposed to the outside, And is assembled to one side of the seat portion 120 by a fastening member such as a bolt. A gasket 140 is provided between the cover 130 and the seating part 120 to prevent a gap from being generated when the cover 130 is assembled to the seating part 120, Thereby blocking the inflow.

The cover 130 is provided with a connector 132 for supplying electric energy to the drive unit 400 so that the drive motor 410 can operate. 400 are mounted, a wire is formed so as to be electrically connected.

The drive shaft 200 is installed in the central space of the valve housing 100 and forms a cam 210 corresponding to the plurality of ports 150 formed in the valve housing 100 on the outer surface thereof. The drive shaft 200 is axially coupled to the drive unit 400 through one end of the through hole 122 of the seating part 120 provided at one end of the valve housing 100 and the other end is coupled to the housing supporter 110 so as to rotate in the forward and reverse directions within a predetermined angle range according to the operation of the drive unit 400. [

As the drive shaft 200 rotates, the cam 210 corresponding to the port 150 formed in the valve housing 100 rotates in the same direction as the drive shaft 200 and moves toward or away from the port 150 And the valve 150 is opened or closed by the valve unit 300 so that the flow of the cooling water introduced into the valve housing 100 is interrupted. The structure of such a valve unit 300 will be described with reference to Figs. 4 and 5. Fig.

FIG. 4 is a perspective view showing a valve unit and a driving unit of the multi-directional switching valve according to the present invention, and FIG. 5 is a sectional view showing the structure of a valve unit of the multi-directional switching valve according to the present invention.

The valve unit 300 includes a cylinder 310 positioned between the cam 210 and the port 150, a piston 320 installed inside the cylinder 310, A rod 340 extending from the piston 320 and passing through the cylinder 310, a pusher 350 provided at the tip of the rod 340 to open and close the port 150, And a first elastic member 360 that provides an elastic force so that the roller 330 comes into close contact with the cam 210.

The cylinder 310 is supported by the valve housing 100 and is positioned between the cam 210 of the drive shaft 200 and the port 150 formed in the valve housing 100. The cylinder 310 has a hollow tube shape in which the piston 320 is linearly moved so that the base end of the cylinder 310 facing the drive shaft 200 is opened. Further, a flange is formed at the outer end of the cylinder 310 and fixed to the valve housing 100.

The piston 320 is installed inside the cylinder 310 described above and linearly moves along the cylinder 310. A rod 340 is integrally formed at the tip of the piston 320 toward the port 150 and a roller 330 is provided at a base end of the drive shaft 200 toward the cam 210.

The roller 330 provided at the base end of the piston 320 is provided so as to roll in a state of being in contact with the cam 210 of the driving shaft 200. The roller 330 rotates about the base end of the piston 320, A pair of supports 321 are integrally formed and a pin 322 is provided across the pair of supports 321 so that the roller 330 is rotatably coupled to the pin 322.

The roller 330 is moved in a linear motion in the cylinder 310 while rolling in contact with the outer surface of the cam 210 as the drive shaft 200 rotates.

At this time, the roller 330 may be made of a material in which the lubricant is absorbed on the roller 330 so as to minimize wear when the roller 330 comes into contact with the cam 210 formed on the driving shaft 200.

The rod 340 is integrally formed with the distal end of the piston 320 and extends through the cylinder 310 toward the port 150 of the valve housing 100. The rod 340 is provided at its tip with a pusher 350 which opens the port 150 in response to the rotation of the cam 210 formed on the drive shaft 200. The pusher 350 is shown in Figures 4 and 5, And a sealing member 370 is provided around the outer surface of the conical shape.

The pusher 350 may be formed by forming a hole having a diameter smaller than the diameter of the rod 340 on the surface facing the tip of the rod 340 so that the pusher 350 and the rod 340 are fixed by force fitting, And the rod 340 and the pusher 350 may be screwed together by forming a screw thread on the outer peripheral surface of the rod.

The sealing member 370 provided in the pusher 350 is made of synthetic resin or synthetic rubber such as urethane or rubber exhibiting elastic restoring force so that when the pusher 350 closes the port 150, (150) to prevent cooling water from leaking between the pusher (350) and the port (150).

The sealing member 370 may be formed integrally with the pusher 350 and the insert injection or may be structured to be detached from the pusher 350 so as to replace the sealing member 370 as necessary.

The pusher 350 may have a conical shape as described above. However, the pusher 350 may have a spherical shape or a cylindrical shape, but the diameter of the outer surface contacting the port 150 may be larger than the diameter of the port 150 And the port can be closely closed, and the shape of the pusher 350 can be variously modified.

The first elastic member 360 is installed inside the cylinder 310 to provide an elastic force such that the roller 330 is brought into close contact with the cam 210 formed on the driving shaft 200. The first elastic member 360 is formed of a coil spring and is positioned at the tip of the piston 320 and interposed between the inner rod 340 of the cylinder 310 and the roller 330, As shown in Fig.

Meanwhile, the driving unit 400 is mounted on a seating part 120 provided at one end of the valve housing 100 to provide a rotational force so that the driving shaft 200 can be rotated. This will be described with reference to FIG.

7 is an exploded perspective view showing a driving unit of the multi-directional switching valve according to the present invention. The drive unit 400 includes a drive motor 410 for converting electrical energy into a rotational force, a pinion 420 mounted on a rotary shaft of the drive motor 410, a screw 420 rotated in engagement with the pinion 420, And a worm gear 440 that rotates in engagement with the screw 430 and is axially coupled to the driving shaft 200. [

In particular, the drive unit 400 includes a bracket 450 to allow the drive unit 400 to be easily assembled to the mount portion 120. The bracket 450 is formed of a plate having a flat surface, The driving unit 400 is assembled into the semi-assembled state by assembling the driving unit 400, the pinion 420, the screw 430 and the worm gear 440 so that the driving unit 400 in the semi- The driving unit 400 can be easily installed.

The bracket 450 for modularizing the drive motor 410, the pinion 420, the screw 430 and the worm gear 440 into a semi-assembled state is provided with an idle shaft 452 for supporting the screw 430 The center of the screw 430 is hollow so that the idle shaft 452 passes through the screw 430 and is supported.

Operation of the multi-directional switching valve according to the present invention having the above-described configuration will be described with reference to Fig.

6 is a cross-sectional view showing an operating state of the valve unit of the multi-directional switching valve according to the present invention. Referring to the drawings, the multi-directional switching valve according to the present invention includes cooling water flowing through an inlet hole 112 formed in a housing supporter 110 of a valve housing 100. Then, the valve unit 300 is operated so that cooling water can be supplied to each cooling element requiring cooling water.

At this time, rotational force from the drive unit 400 is supplied to the drive shaft 200 for the operation of the valve unit 300 so that the cam 210 of the drive shaft 200 moves in the same direction as the drive shaft 200 .

As the drive shaft 200 rotates, the roller 330 closely attached to the cam 210 is positioned at the top dead center and the bottom dead center of the cam 210, so that the port 150 formed in the valve housing 100 And the flow of the cooling water is interrupted.

At this time, the drive shaft 200 is formed with a plurality of cams 210 corresponding to the ports 150 formed in the valve housing 100, and each of the cams 210 includes the valve unit 300, 200 are rotated so that one port 150 is opened and cooling water is supplied and another port 150 is closed so that the supply of cooling water is blocked.

A plurality of ports 150 formed in the valve housing 100 can be opened or closed by a single drive shaft 200 so that the power for operating the valve unit 300 Not only the delivery system is simplified, but also the plurality of ports 150 can be individually controlled so that the flow of the cooling water can be precisely controlled.

The rotation of the cam 210 formed on the drive shaft 200 is converted into a linear movement so that the valve unit 300 for opening and closing the port 150 performs rolling motion with the cam 210, It is possible to prevent leakage due to wear of parts and increase the lifetime of the product.

In addition, the drive unit 400 that provides the rotational force to the drive shaft 200 is modularized into a semi-assembled state, so that the drive unit 400 can be quickly and easily installed in the mount portion 120, .

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. .

For example, the multi-directional switching valve according to the present invention may have a structure in which the valve unit has the structure as shown in FIGS. 4 and 5, but in some cases, the second elastic member 380 is provided, As shown in FIG. This will be described with reference to FIG.

8 is a cross-sectional view showing another embodiment of the valve unit of the multi-directional switching valve according to the present invention. The valve unit 300 is configured such that when the pusher 350 closes the port 150, the pusher 350 pushes the outer tip of the cylinder 310 and the pusher 350, And a second elastic member 380 is provided between the second elastic member 350 and the second elastic member 380. Such a second elastic member 380 can be realized by a coil spring as shown in Fig.

The tip of the rod 340 projects through the pusher 350 and protrudes forward of the port 150 so that the pusher 350 and the rod 340 have a rigid structure, And the rod 340 and the rod 340 can be fixed.

When the rod 340 passes through the pusher 350 as described above, when the rod 340 and the pusher 350 are assembled, the tip of the rod 340 is passed through the pusher 350 and then the rod 340 It is possible to install the pusher 350 on the rod 340 simply and quickly by providing the snap ring 390 at the tip of the rod 340.

On the other hand, as described above, the valve unit may be provided at the base end of the piston 320 with the roller 330 rolling in contact with the cam 210, but in some cases, a rolling ball may be provided instead of the roller It is possible. This will be described with reference to FIG.

9 is a cross-sectional view showing another embodiment of the valve unit of the multi-directional switching valve according to the present invention. Referring to the drawings, the valve unit 300 is provided with a rolling ball 330a having a spherical shape at the base end of the piston 320, and the rolling ball 330a rolls according to the rotation of the cam 210 .

To this end, the base of the piston 320 is provided with a buried groove 323 in which a rolling ball 330a is embedded, and a ball 330a in the form of a sphere is mounted in the buried groove 323. At this time, a part of the rolling ball 330a protrudes outwardly through the base end of the piston 320 and is brought into contact with the cam 210 of the driving shaft 200 by an elastic force exerted from the first elastic member 360 The rolling motion of the driving shaft 200 is performed.

When the rolling ball is provided at the base end of the piston 320, the rolling ball 330a rolls over the entire surface when the cam 210 rotates, so that the rolling ball 330a moves along the cam 210 Wear of a specific portion can be minimized, so that opening and closing of the port 150 can be controlled precisely.

5 and 8, when the roller 330 is provided at the base end of the piston 320, the contact portion between the cam 210 and the roller 330 is limited to the circumferential direction of the roller 330 9, when spherical-shaped ball 330a is provided at the base end of the piston 320 as shown in FIG. 9, the spherical ball 330a is formed in accordance with the load acting on the cam 210 and the ball 330a. And the cam 210 are different from each other, the portion where the abrasion occurs occurs uniformly over the entire area of the rolling ball 330a, so that uneven wear does not occur and the opening and closing of the port 150 can be precisely controlled have.

100: valve housing 110: housing supporter
112: inlet hole 114: support hole
116: rib 120:
122: through hole 130: cover
132: connector 140: gasket
150: Port 200: Drive shaft
210: cam 300: valve unit
310: cylinder 320: piston
321: Support 322: Pin
323: buried groove 330: roller
330a: cloud ball 340: rod
350: pusher 360: first elastic member
370: sealing member 380: second elastic member
390: snap ring 400: drive unit
410: drive motor 420: pinion
430: screw 440: worm gear
450: Bracket 452: Idle shaft

Claims (8)

A valve housing formed with a hollow pipe structure and having a plurality of ports for discharging cooling water supplied to the central space to respective external cooling elements;
A drive shaft installed in a central space of the valve housing and having an outer surface formed with cams corresponding to the ports, respectively;
A valve unit interlocked with the cam in accordance with rotation of the drive shaft to open and close the port; And
And a driving unit installed at one end of the valve housing to provide rotational force to the driving shaft,
The valve unit
A cylinder supported in the valve housing and positioned between the cam and the port;
A piston installed inside the cylinder and moving linearly;
A roller installed at a base end of the piston and rolling in accordance with the rotation of the cam;
A rod extending through the cylinder at the tip of the piston and extending toward the port;
A pushbutton provided at a distal end of the rod for opening and closing the port in accordance with rotation of the cam; And
And a first elastic member provided inside the cylinder to provide an elastic force to bring the roller in close contact with the cam.
The method according to claim 1,
The valve housing
A housing supporter formed at the other end of the valve housing to receive cooling water and bear the other end of the driving shaft;
A seating part formed at one end of a valve housing facing the housing supporter and mounted with the driving unit; And
And a cover provided with a connector for closing the seat portion and supplying electric energy to the drive unit.
delete A valve housing formed with a hollow pipe structure and having a plurality of ports for discharging cooling water supplied to the central space to respective external cooling elements;
A drive shaft installed in a central space of the valve housing and having an outer surface formed with cams corresponding to the ports, respectively;
A valve unit interlocked with the cam in accordance with rotation of the drive shaft to open and close the port; And
And a driving unit installed at one end of the valve housing to provide rotational force to the driving shaft,
The valve unit
A cylinder supported in the valve housing and positioned between the cam and the port;
A piston installed inside the cylinder and moving linearly;
A cloud ball in which a part of the piston is embedded at a base end thereof and rolls in accordance with the rotation of the cam;
A rod extending through the cylinder at the tip of the piston and extending toward the port;
A pushbutton provided at a distal end of the rod for opening and closing the port in accordance with rotation of the cam; And
And a first elastic member installed inside the cylinder to provide an elastic force to bring the rolling ball into close contact with the cam.
The method according to claim 1 or 4,
Wherein the pushbutton is provided with a sealing member around its outer surface.
The method according to claim 1 or 4,
The valve unit
Further comprising a second resilient member interposed between the outer end of the cylinder and the pusher so that when the pushbutton closes the port, the pusher presses against the port.
The method according to claim 1 or 4,
The rod
And a snap ring is provided at a tip end of the rod so as to fix the pusher.
The method of claim 2,
The drive unit
A pinion provided on a rotary shaft of the drive motor;
A screw rotating in engagement with the pinion;
A worm gear rotatably engaged with the screw and axially engaged with the cam shaft; And
And a bracket provided with the driving motor and bearing the screw,
Wherein the drive unit is mounted to a seat portion of the valve housing in a state where a driving motor, a pinion, a screw, and a worm gear are assembled to the bracket.

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