【Instruction manual】
Vacuum pump

Model: CRV-16V, 25V■

Thank you for purchasing the CRV
rotary-type vacuum pump.

■

Please read this instruction manual
carefully before use.

■

Keep this manual in a place where it
can be referred to at any time and lookafter it carefully.

(V1.00)

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For using it safely.
The following safety precautions are provided to prevent damage and danger to personnel
and to provide instructions on the correct usage of this product.

These precautions are classified into 3 categories; DANGER, WARNING, and CAUTION,according to the degree of possible injury or damage and the degree of impedence of suchinjury or damage.

Indicates an impending hazardous situation which may
arise due to improper handling or operation and could
result in serious bodily injury or death.
Indicates a potentially hazardous situation which may
arise due to improper handling or operation and could
result in serious bodily injury or death.
Indicates a potentially hazardous situation which may
arise due to improper handling or operation and could
result in bodily injury or property-damage only accidents.

① Do not use in flammable and/or explosive atmosphere. It may cause fire.
② Do not put flammable solvent or inflammables around a pump. It may cause fire.
③ Do not put any obstacle that may disturb the ventilation around a pump. It may cause
overheating and can be the source of burnings and/or fire.

① Make sure to disconnect the electrical supply before installation or maintenance of thepump.
Do not touch the electrical wiring to avoid electric shock if the pump starts operatingsuddenly.
② Make sure the earth ground connection is properly made in order to avoid electric shockor pump failure. We recommend to install an earth leakage circuit breaker.
③ Supply the correct rated voltage to the pump motor. Apply over rated voltage may cause
motor damage or failure and/or fire of the motor.
④ Do not put your finger or anything else into the motor orifice. It may cause electric shock,injury or fire.
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About setting and operating① Make sure the ambient temperature range is within 7 ~ 40℃ when the pump isoperating. .
② Make sure that no corrosive gas, water or oil gets sucked into the pump vacuum port.
(Avoid the suction of air with high temperature or high humidity)③ Avoid places with lot of dust.
④ Install indoor and make sure to ensure sufficient ventilation around the pump.
⑤ Install in a place with no explosive gas.
⑥ Do not expose to direct sunlight.
⑦ Install it in a place without danger of ignition⑧ Make sure to use your both hand when carrying the pump.
⑨ Blade abrasion particles are blown through the exhaust port due to the blade friction
when the pump is operating. Set the piping with outdoor exhaust if necessary.
⑩ When the pump is operating, never touch the fan, the motor or other part of the pump. Itcauses injury.
⑪ Use the pump within the operating vacuum pressure range.
(See below table for reference)

Model

Operating vacuum pressure range

CRV-16V
CRV-25V-60 kPa ～ 0 (Atmospheric pressure)⑫ The pump temperature increases when operating and is still high after stop of operation.
As it causes burns, never touch the pump when it is operating or just after operating.
⑬ For safety reasons, install an overcurrent protective device and an earth leakage circuitbreaker.

About maintenance / repair① When the pump stops unusually, wait until the pump cools down before. Make
sure the temperature is low enough to perform any checking.
② Assembly and disassembly of the pump requires technical knowledge.

③ Make sure to disconnect the electrical supply before installation or maintenance ofthe pump. Do not touch the electrical wiring to avoid electric shock if the pumpstarts operating suddenly.

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TABLE OF CONTENTS
1. PRECAUTIONS BEFORE USING THE PUMP ................................................................. 51) Pump appearance inspection ......................................................................................... 52）Preparation...................................................................................................................... 5A) Site installation............................................................................................................ 5B) Pump installation ........................................................................................................ 5C) Pump placement ........................................................................................................ 5D) Piping .......................................................................................................................... 53）Pump motor operation and protection ............................................................................ 64）Pump start-up, operation and stopping procedures ....................................................... 65）Pump storage .................................................................................................................. 62. PUMP CONSTRUCTION ................................................................................................... 7
3. TROUBLE SHOOTING OF PUMP .................................................................................... 81）The vacuum pressure cannot be adjusted to a high vacuum......................................... 82）Abnormal noise ............................................................................................................... 83）Stop of a pump ................................................................................................................ 93. DISASSEMBLY AND ASSEMBLY PROCEDURES(EXCHANGE OF A BLADES, AND REMOVAL OF DEBRIS/FOREIGN SUBSTANCE) 101）Disassembly procedure ................................................................................................ 102）Re-assembly procedure ................................................................................................ 135. PERIODICAL INSPECTION ............................................................................................ 171) Filter cleaning ............................................................................................................... 172) Piping check ................................................................................................................. 173) Filter assembly procedure ............................................................................................ 174) Check of the pump ....................................................................................................... 175) Rotating part inspection ................................................................................................ 186) Blade maintenance and replacement........................................................................... 18EXPLODED VIEW................................................................................................................ 19
PARTS LIST ...................................................................................................................... 20

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1. PRECAUTIONS BEFORE USING THE PUMP
1) Pump appearance inspection
Perform a visual inspection of the pump and check whether there is any damaged partor screw loose, etc.
2）PreparationA) Site installation① Install in a place without danger of ignition.
② Install in a place/environment that would not affect the proper operation ofthe pump (no gas, no chemicals, etc.)③ Install in a place with no water drop, no oil drop or any other liquid drop. Donot expose to direct sunlight.
④ The allowable ambient air temperature range for this pump is 7～40℃.
In the case there is heating source close to the pump, make sure the ambient
air temperature does not exceed 40℃.
⑤ Use in a confined space may cause operation failure due to the heatgenerated by the pump. Make sure to ensure sufficient ventilation around thepump and be careful not to exceed the allowable ambient temperature.
⑥ Install in a place where it is not exposed to humidity or dust.
⑦ Please install in a place with sufficient space for check and maintenance.
B) Pump installation① Please install the pump horizontally and in a stable place.
② As the pump makes vibrations during operation, install rubber cushion.
③ Do not drop the pump when carrying it.
C) Pump placement
Make sure to always keep enough space around the fan cover. Provide atleast 10 cm free space between the wall and the fan cover for heat dissipation.
D) Piping① Remove foreign debris from the piping by using air blow if any.
④ Shorten the piping as much as possible without stress on piping
connections.
⑤ Make sure that no oil or other kind of liquid will be sucked into the piping. Inthe case there is oil or moisture in the operating environment, install an oil mist
separator to prevent malfunction of the pump.
⑥ Depending on operating environment, install a precision filter (30
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micrometers or less)⑦ When the pump stops, if a reverse phenomenon occur, install a checkvalve at vacuum or exhaust port.

Piping illustration

3）Pump motor operation and protectionA) The rotation direction is shown on the pump cover.
B) Protection device preparation: there is no overheat control device (thermalprotector) installed on the pump; install an overcurrent protective device andan earth leakage circuit breaker.
4）Pump start-up, operation and stopping procedures
A) Set the vacuum at the minimum value (atmospheric pressure) before
switching the power on.
B) When operating, the temperature of the pump increases; this is a normal
phenomenon.
C) Set the vacuum at the minimum value (atmospheric pressure) before stopping
the pump.
5）Pump storage
After purchasing and using the pump, when you do not use it temporarily, be careful ofthe following matters.
A) Cover and save indoors.
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B) Avoid places containing oil and water.
C) Do not store in place with high humidity. Store in place where the temperatureis under 40℃.

2. PUMP CONSTRUCTION

No.

Part name

No.

Part name1.

Element

13.

Gap Washer

2.

Inlet Port Side Rear Lid

14.

Translucent Gap Washer

3.

Outlet Port Side Rear Lid

15.

Blade

4.

Filter

16

Rotor

5.

Inlet Port Side Front Lid

17.

Frame

6.

Outlet Port Side Front Lid18.

Regulator

7.

Vacuum Gauge

19.

Coupling Lid

8.

Pump Lid20.

Base Plate

9.

Fan

21.

Coupling

10.

Fan Cover

22.

Motor

11.

Bearing

23.

Pump Rear Lid

12.

Bearing Washer
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3. TROUBLE SHOOTING OF PUMP
1）The vacuum pressure cannot be adjusted to a high vacuum.
Cause: suction flow decrease due to clogging of filter.
-Countermeasure: remove the filter and perform an air blow to remove oil. If oil
cannot be removed this way, replace with a new filter.

Cause: the blade does not rotate because of chip, dirt, liquid etc.
-

Countermeasure: follow the disassembly procedure steps, remove the debrisor substance.

Cause: the blade does not rotate due to rusting from water intrusion.
-

Countermeasure: Disassemble the pump, remove the rust.

Cause: the vacuum gauge is broken.
-

Countermeasure: change the vacuum gauge.

Cause: leakage from the piping or filter.
-

Countermeasure: change the piping or filter.

Cause: screw loosening.
-

Countermeasure: re-tighten the screw.

Cause: Slow speed rotation because of motor failure.
-Countermeasure: repair or change the motor.

Cause：blade is broken.
-

Countermeasure: replace the blade with a new one.

Cause: blade size difference.
-

Countermeasure: replace with correct sized blade.

Cause: blade wearing.
-Countermeasure: replace the blade with a new one.

2）Abnormal noise
Cause: the vacuum pressure in use is too high.
-Countermeasure: adjust the vacuum pressure within the operating range using
the regulator.

Cause: the coupling is inclined.
-

Countermeasure: Unscrew and re-screw the coupling correctly in parallelposition.

Cause: screw loosening.
-Countermeasure: re-tighten the screw.

Cause: Air cannot be sucked due to filter clogging.
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oil. If oil cannot be removed by this way, replace the filter with a new one.
Cause: blade damaged by foreign debris.
-

Countermeasure: Disassemble the pump, clean it and replace the blades.

3）Stop of a pump
Cause: blade damaged by foreign matter.
-Countermeasure: disassemble the pump, clean it and replace the blades.

Cause: Friction of rotor and/or other parts when pump is operating under overpressure.
-Countermeasure: disassemble the pump, replace the parts.

Cause: failure of the electrical system-Countermeasure: check the state of wire and connecting terminals, and repair
in case of poor contact and/or disconnection.

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3. DISASSEMBLY AND ASSEMBLY PROCEDURES(Exchange of a blades, and removal of debris/foreign substance)
・Disassembly and assembly process requires technical knowledge.
Installation and maintenance must be performed by knowledgeable personnel whounderstand how pneumatic and vacuum products are to be applied. Do not disassembly
the pump is you do no hat sufficient knowledge about vacuum pumps.
・If required, proceed with disassembly of the pump by following below instructions.
1）Disassembly procedure

1-0
Remove the 2 screws fromthe filter and frame. Remove
the filter body.

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1-1
Remove the screws from thebearing, remove the bearing
washer, the cap washer andtranslucent cap washer. Don’tlose

theseparts

afterremoving.

1-2
Remove the screws from thepump lid.

1-3
Remove the 3 nuts fixed tothe lid. Remove the pump lid.
Do not scratch the frame sideof the pump or the pump lid.

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1-4
Insert the collar, the bearing,
the translucent washer, thegap washer and the bearing
washer on the pump. Tighten
temporary with the screws.
(keep at least 1mm space
between the pump lid andcollar)

1-5Remove the blades andmake sure to remember thecorrect direction of the bladesedge when replacing it.

1-6
Use the extracting jig at theopposite side of the motor andpush out. Be careful not toscratch the frame or the motor.

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1-7
Remove the pump lid fromthe frame.
Do not clean the bearing withwashing solution.

2）Re-assembly procedure

2-1
Facing the rotor at motorside, insert the pump lid, thecollar and the bearing.

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2-2
Use a hammer to insert thebearing into the rotor.
To prevent any damage ofthe rotor, but a wooden block
between the table and therotor.

2-3
If the blade is damaged orworn, replace it with a newone.
Make sure the blade is insert
and oriented in the correct
direction.

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2-4
Put the rotor in the frame andinsert the pins. Make sure thatthe pin and the frame are set in
the correct direction. Tighten
the screws firmly. Make surethe direction of rotation andframe direction are correct.

2-5
Put the rotor in the pumprear lid and insert the bearing
in the shaft of the rotor.
Inset the pins and tighten
the screws firmly to fix it.

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2-6
Use a hammer and hit thebearing so that the collar, therotor and the bearing arecompletely in contact.

2-7
Firmly tighten the screw ofthe bearing.

2-8
Make

therotor

rotating

clockwise

andcounterclockwise. Check thattherotationsmoothlyisperformed

withoutany

resistance.

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5. PERIODICAL INSPECTION
1) Filter cleaning
Perform a daily check of the filter element condition.
When it becomes dirty, remove the dirt by using an air blower.
In the case the oil cannot be removed by this way, replace with a new filter element.
2) Piping check
Check periodically and make sure there is no loose, damaged or broken piping.
3) Filter assembly procedure

No.

Part name

No.

Part name

1

Knob

5

Spring2

Gasket6

Element

3

Inlet Port Side Rear Lid

7Screw

4

Gasket8Filter Main Body

4) Check of the pump
Check that the pump is operating correctly. Check that the performance of thepump is not decreasing.
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Replacement of parts will be required in the case of abnormal sound generation.
Contact your representative for maintenance parts purchasing and repair thepump.
5) Rotating part inspection
The pump is rotating by using the rotating part and the coupling.
①Inspection
Inspect both side of the coupling. Check the space between the coupling.
②Coupling position correction
If there is a problem with the coupling, use a scale and adjust its position.
(Location may be the motor or the pump edges)
If the plastic is deteriorated, replace it with a new one.
6) Blade maintenance and replacement
Replace the blade when the height reaches 14mm height.

(H) Blade height

Model(W) Blade width

CRV-16V

66 mm

34 mm

26.5 mm

CRV-25V

95 mm

38 mm

29.5 mm

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EXPLODED VIEW

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PARTSNo.

LISTPart No.

Part name

Quantity1M0037-2

ELEMENT

12M0052-2

INLET PORT SIDE REAR LID

13M0052-1

OUTLET PORT SIDE REAR LID

14MS024

FILTER MAIN BODY

15MS024-1-2

INLET PORT SIDE FRONT LID

16MS024-1-1

OUTLET PORT SIDE FRONT LID

17M0041-3

VACUUM GAUGE

18MS008-3

PUMP LID

19M0025-4

FAN

110M0024-3

FAN COVER

111M0003-4

BEAR0ING

212M0011-01

BEARING WASHER

213M0051

GAP WASHER

214M0051-2

TRANSLUCENT GAP WASHER

215M0001-3

BLADE

416MS017-02ROTOR

117MS009-4

FRAME

118MS017-02

REGULATOR

119M0047

COUPLING COVER

120Z0002-1

BASE PLATE

121M0045-7

COUPLING

122M0036-1

MOTOR

123

M0008-09-6

SCREW

224M0049

PIN

425

M0008-07-3

RESISTING SCREW

426

M0009

NUT

427

M0010-1-05

SPRING WASHER

428

M0010-3-04

FLAT WASHER

429

M0022-2

CUSHION RUBBER FEET

430

M0008-08-4

SCREW

231

M0008-02-2-2

SCREW

8

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