KR20230031400A - Cylinder type NVH vacuum pump for vehicle - Google Patents

Abstract

In accordance with the present invention, disclosed is an NVH reduction type cylinder vacuum pump for a vehicle. In accordance with the present invention, the NVH reduction type cylinder vacuum pump includes: a hollow tubular cylinder forming a chamber provided with an intake and exhaust port equipped with a check valve on one side and having a motor unit provided with a rotary shaft on the other side; a one-way shaft fitted into the outer surface of the rotary shaft to perform one-way rotation while enabling axial sliding movement; a cylindrical cam coupled to the outer surface of the one-way shaft to be rotated interconnectedly, and having a contour groove formed on the outer surface, into which a fixing protrusion protruding from the inside of the cylinder is inserted; and a plunger provided on one side of the cylindrical cam to shield the chamber and having an outer circumference slidingly coming into tight contact with the inner surface of the cylinder to vary a volume in the chamber. In accordance with the present invention, as the rotary shaft performing one-way rotation by receiving power and the cylindrical cam and the plunger axially coupled to the shaft to perform rotation and linear movement are operated by an inertial motion without being interrupted, the NVH reduction type cylinder vacuum pump can minimize the occurrence of an impact or vibrations during the operation procedure, thereby increasing durability and lifespan as well as increasing driving efficiency and guaranteeing the reliability of operation.

Description

NVH reducing cylinder vacuum pump for vehicles {Cylinder type NVH vacuum pump for vehicle}

The present invention relates to an NVH reducing cylinder vacuum pump for a vehicle, and more particularly, is configured to receive power and operate independently regardless of whether the engine of a vehicle is driven, enabling the generation and supply of vacuum pressure at all times, and particularly in a straight line. It relates to a vehicle NVH reducing cylinder vacuum pump capable of reducing noise and shock while ensuring reliability of operation while increasing driving efficiency through a configuration arranged in a .

In general, a braking system used for the purpose of decelerating or stopping a vehicle in motion includes a brake pedal that increases and transmits the driver's operating force using a link or hydraulic pressure, and a braking system that generates braking force by receiving the operating force of the brake pedal. It consists of a device, and a vacuum pump using vacuum or compressed air is configured to lighten the operating force by increasing the pedal force of the brake pedal applied by the driver.

The vacuum pump that assists this braking force is a hydroback method using compressed air by installing a separate vacuum compressor for large trucks or vehicles with heavy loads. It is connected to the surge tank where the negative pressure of the intake manifold is formed, and the master bag method using the vacuum obtained through this is applied.

In particular, the master bag type vacuum pump applied to small vehicles is driven when the negative pressure of the engine is not formed, launches and releases the oil toward the brake booster through the surge tank, and usually performs the function of supplying negative pressure to the air, and most of the negative pressure of the engine An electric vacuum pump (EVP, Electric Vacuum Pump) that assists is used.

Looking at the structure of an electric vacuum pump usually installed in a small vehicle, it consists of a main body having a chamber for forming a vacuum pressure, and a drive unit provided inside the main body to generate a vacuum pressure, and the drive unit is again a rotor assembly. It consists of a rotor assembly, a stator assembly, a housing assembly, and an electrical part, and the rotor assembly includes an impeller, a magnet, a rotor shaft, and the like, and the stator assembly includes a core, A coil and the like are included, and the housing assembly includes a bush, a bearing, and the like for supporting the rotor assembly and the stator assembly. Finally, the electrical part consists of a circuit board and electric wires.

The electric vacuum pump according to the prior art having such a configuration not only has a disadvantage in that the structure is complicated and the reliability of operation is greatly reduced due to unstable balancing between the rotor assembly and the stator assembly. In addition, in order to reinforce rotor balancing, the rotor assembly A structure installed at the bottom of my rotor shaft was proposed, but there was a very poor assembly.

As a prior art related to an electric vacuum pump according to the prior art, an electric vacuum pump has been proposed through Korean Patent Registration No. 10-1738929 (May 17, 2017), and in claim 2, 'In an electric vacuum pump, electric a driving module including a motor and providing a driving force by externally applied power or an engine; a housing provided on one side to be coupled to the driving module; a pump module having a suction hole through which air is sucked and a discharge hole through which the sucked air is discharged, and coupled to the other side of the housing; and a pump cover coupled to the housing to cover the pump module, wherein the pump module includes a rotor coupled to the drive module to rotate, a vane slidably coupled to the rotor, and an outer end of the vane. It includes a cam ring for guiding a rotational path of the cam ring, and a side plate having an intake area in which air is sucked and a discharge area in which compressed air is discharged by being coupled with the cam ring and the rotor interposed therebetween and forming an appearance, the side plate A foreign material collecting groove recessed from the sliding surface is formed on a sliding surface on which the plate contacts the vane and the rotor, and the rotor includes a slot provided to allow the vane to enter and exit, and the foreign material collecting groove has an outer diameter of the rotor An electric vacuum pump characterized in that it is formed between an imaginary circumference connected to an inner end of the slot.'

As another prior art, an electric vacuum pump has been proposed through Republic of Korea Patent Registration No. 10-2140330 (July 27, 2020), and claim 1 states that 'In an electric vacuum pump, driving force is applied by externally applied power. A motor housing for supporting a motor that provides; A rotor rotatably coupled to the rotor shaft coupled to the motor, a vane coupled to be retractable to the rotor, a cam ring in contact with an end of the vane, and coupled to the cam ring to accommodate the rotor and the vane a pump module equipped with a side plate and coupled to the motor housing to pressurize the sucked air and discharge it through an outlet; a pump cover accommodating the pump module and having a cover rib protruding from the inside toward the pump module and coupled to the motor housing; A cover rubber member having a skirt having one side coupled to the cover rib and the other side supported by the side plate; wherein, the cover rib is divided in a radial direction along the circumference and has a plurality of rib slots formed therethrough with a set width. And, the cover rib is formed with a rubber member holding jaw recessed from the outer circumferential plate surface so that the cover rubber member can be coupled thereto, and the cover rubber member is coupled to the rubber member holding jaw to partially close the rib slot and air A cover rib rubber gap for guiding the flow of is formed, and the cover rubber member is provided with an intermediate plate having a middle hole penetrating the central region in a plate shape crossing the skirt of a hollow band shape, and the cross-sectional area of the middle hole is An electric vacuum pump characterized in that the cross-sectional area of the gap of the cover rib rubber is larger than that of the cover rib rubber.' is disclosed.

However, these electric vacuum pumps according to the prior art have a complicated structure and are difficult to compact, and there is a problem of durability degradation due to excessive vibration shock and noise during the vacuum pressure generation process. It is difficult to miniaturize and simplify the shape, and as a result, the degree of freedom of design of a vehicle to which it is applied is reduced.

Patent Document 1: Registered Patent Publication No. 10-2105191 (2020.04.21.) Patent Document 2: Patent Registration No. 10-1298264 (2013.08.13.) Patent Document 3: Registered Patent Publication No. 10-1738929 (May 17, 2017) Patent Document 4: Registered Patent Publication No. 10-2140330 (2020.07.27.)

The present invention was created to solve the problems of the prior art as described above, and an object of the present invention is to arrange the structure of the motor and cylinder in a straight line to simplify the form and improve the structure to improve the efficiency of power transmission of the drive unit. It is to provide a vehicle NVH reducing cylinder vacuum pump that can improve the reliability and durability of operation by increasing, and also improve the freedom of the installation site and the convenience of maintenance by simplifying and compacting the form.

In particular, the present invention provides a structure capable of continuous operation by inertial force to improve noise, vibration, and resulting harshness (NVH), thereby improving reliability and customer satisfaction for products equipped with it. It is to provide a NVH reducing cylinder vacuum pump for vehicles that can be increased.

An NVH reducing cylinder vacuum pump for vehicles according to a preferred embodiment of the present invention for realizing the above object is a hollow tube having a chamber having an intake/exhaust port with a check valve installed on one side and a motor unit having a rotating shaft on the other side. shaped cylinder; A one-way shaft that is fitted to the outer surface of the rotation shaft and is capable of sliding in an axial direction while rotating in one direction; A cylindrical cam coupled to the outer surface of the one-way shaft to rotate interlockingly, forming a contour groove on the outer surface and inserting a fixing protrusion protruding from the inside of the cylinder; It is characterized in that it consists of a plunger provided on one side of the cylindrical cam to shield the chamber, and the outer surface slides closely to the inner wall surface of the cylinder to change the volume in the chamber.

As a preferred feature of the present invention, the plunger is provided to have a linear displacement while rotating in conjunction with the cylindrical cam, and a gasket is provided on its outer surface while being in close contact with the inner wall surface of the cylinder; One or both of them are provided with a stopper for regulating the linear movement distance of the cylindrical cam; the fixing protrusion is slide-fitted into the contour groove of the cylindrical cam to induce displacement in the axial direction when the cylindrical cam rotates To reduce frictional resistance, the ends are either curved or coated with Teflon.

As another preferred feature of the present invention, the rotating shaft is axially disposed across the inner center of the cylinder, but both ends are rotatably supported by shaft bearings on both sides of the cylinder;

The one-way shaft is a linear rotary oilless bearing capable of axial movement while forming one-way rotation with respect to the rotation shaft while regulating reverse rotation.

The NVH reducing cylinder vacuum pump for vehicles according to the present invention is operated by inertial motion without interruption between a rotating shaft that rotates in one direction by receiving power and a cylindrical cam and plunger that are coupled to the rotating shaft to make rotation and linear motion. It is possible to minimize the occurrence of shock or vibration, thereby extending durability and life, as well as increasing drive efficiency and ensuring operational reliability.

Features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Prior to this, the terms or words used in this specification and claims should not be interpreted in a conventional and dictionary sense, and the inventor may appropriately define the concept of the term in order to explain his or her invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

1 is a perspective view showing an NVH reducing cylinder vacuum pump for vehicles according to the present invention;
Figure 2 is a partially cut perspective view for explaining the internal configuration of the NVH reducing cylinder vacuum pump for vehicles according to the present invention;
3 is a cross-sectional view showing the internal configuration of a NVH reducing cylinder vacuum pump for vehicles according to an embodiment of the present invention;
Figure 4 is a cross-sectional view for explaining the operation configuration of Figure 3;
5 is a cross-sectional view showing the internal configuration of a NVH reducing cylinder vacuum pump for vehicles according to a modified embodiment of the present invention;
6 is a cross-sectional view for explaining the operation configuration of FIG. 5;
7 is a cutaway perspective view showing the configuration of the main parts of the NVH reducing cylinder vacuum pump for vehicles according to the present invention;
8 is a cross-sectional view of the configuration of the main parts of the NVH reducing cylinder vacuum pump for vehicles shown in FIG. 7;
9 is an image showing an embodiment of a one-way shaft in the NVH reducing cylinder vacuum pump for vehicles according to the present invention.

Hereinafter, the configuration and operation of an embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, it is not intended to limit the present invention to a specific disclosure, and it should be understood to include all changes, equivalents, or substitutes included in the spirit and technical scope of the present invention. In this application, terms such as "comprise" or "having" are intended to designate that a feature, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features, steps, or operations However, it should be understood that it does not preclude in advance the possibility of the presence or addition of components, parts, or combinations thereof. That is, throughout the specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

In addition, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this application, it should not be interpreted in an ideal or excessively formal meaning. don't

Here, repeated descriptions, well-known functions that may unnecessarily obscure the subject matter of the present invention, and specific descriptions of configurations are omitted in order not to obscure the subject matter of the present invention. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clarity.

1 is a perspective view showing an NVH reducing cylinder vacuum pump for vehicles according to the present invention, and FIG. 2 is a perspective view partially cut away for explaining the internal configuration of the NVH reducing cylinder vacuum pump for vehicles according to the present invention.

In the drawing, a cylinder 10 formed in the shape of a hollow cylindrical tube and forming an outer body, a motor 20 composed of a rotor and a stator installed on one side of the inside of the cylinder 10, and the motor 20 A cylindrical cam 40 formed with a contour groove 41 for inducing linear displacement on the outer surface and integrated on one side of the cylindrical cam 40 by being shaft-coupled to the rotating shaft 21 of the ) to have rotation and linear displacement. It is provided in a disk shape with rotation and linear displacement by interlocking, and its outer surface is formed in the plunger 50 in frictional contact while sliding on the inner wall surface of the cylinder 10 and in the space on one side of the plunger 50. An NVH reducing cylinder vacuum pump 1 for a vehicle consisting of a chamber 15 and an intake port 11 and an exhaust port 12 connected to the chamber 15 is shown.

3 is a cross-sectional view showing the internal configuration of the NVH reducing cylinder vacuum pump for vehicles according to an embodiment of the present invention.

In the drawing, a cylinder 10 provided in a tubular shape of a hollow length member, a rotor (unsigned) and a stator (unsigned) installed on the left side of the inner space of the cylinder 10 based on the drawing, and a rotating shaft 21 A motor 20 consisting of a shaft bearing 22 rotatably supported by both ends of the rotating shaft 21 disposed across the inner center of the cylinder 10 at both sides of the cylinder 10, A one-way shaft 30 fitted to one side of the rotating shaft 21 and provided with one-way rotation and linear displacement, and coupled to one end of the one-way shaft 30 to have rotation and linear displacement integrally A cylindrical cam 40 having a contour groove 41 for guiding displacement in the axial direction is formed on the outer surface, and the inner surface of the cylinder 10 is slide-fitted into the contour groove 41 to induce axial displacement. A fixing protrusion 14 protruding from one side of the wall surface and a gasket ( 51), a chamber 15 which is a space on one side of the plunger 50, and an intake port 11 connected to the chamber 15 for inhaling air or exhausting compressed air from the outside. ), an exhaust port 12, and a check valve 13 installed on each intake port 11 and exhaust port 12 to allow air to flow in only one direction (13). ) is shown.

3 shows a state for sucking air into the chamber 15 .

4 is a cross-sectional view for explaining the operation configuration of FIG. 3 .

In the drawing, the cylindrical cam 40 and the plunger 50 provided to have rotation and linear displacement by the one-way shaft 30 on the rotation shaft 21 by the drive of the motor 20 are rotated to the right with reference to the drawing. It shows a state in which the volume of the chamber 15 is reduced by moving, and at this time, the air in the chamber 15 is discharged to the outside through the exhaust port 12 is shown.

5 is a cross-sectional view showing the internal configuration of an NVH reducing cylinder vacuum pump for vehicles according to a modified embodiment of the present invention, and FIG. 6 is a cross-sectional view for explaining the operation configuration of FIG. 5 .

In the drawing, there is shown a vehicle NVH reducing cylinder vacuum pump 1 having a configuration substantially the same as that of FIGS. 3 and 4 described above, except that the cylindrical cam 40 and the plunger 50 are spaced apart from each other. A configuration is shown, which illustrates that it may be modified for manufacturing and assembly convenience.

7 is a cut-away perspective view showing the configuration of main parts of the NVH reducing cylinder vacuum pump for vehicles according to the present invention, and FIG. 8 is a cross-sectional view of the main parts of the NVH reducing cylinder vacuum pump for vehicles shown in FIG. 7 .

In the drawing, the rotary shaft 21 of the motor 20 that generates driving force by supplying power, and the one-way bearing or A one-way shaft 30 of a method called a ratchet bearing is provided, and the one-way shaft 30 at this time is configured to be axially movable along the axis of the rotation shaft 21 with one-way rotation, which is A well-known thrust one-way bearing or a linear rotary oilless bearing may be used, so a detailed description thereof will be omitted.

Referring to the above drawings, the configuration of the vehicle NVH reducing cylinder vacuum pump according to the present invention will be described in detail.

The present invention largely forms a cylinder 10 that forms an outer body and provides a space in which components can be installed and a space in which air is sucked and compressed, and is installed on one side of the cylinder 10 to supply power. A motor 20 receiving a supply and generating rotational driving force, and a one-way shaft provided to be linearly moved along the axis of the rotation shaft 21 while being shaft-fitted on the rotation shaft 21 of the motor 20 to achieve one-way rotation (30), a cylindrical cam 40 integrally coupled to one side of the one-way shaft 30 and having rotation and linear displacement by interlocking, and a cylindrical cam 40 provided on one side of the cylindrical cam 40 and integrally interlocking It is composed of a plunger 50 that changes the space size of the chamber 15 provided in the cylinder 10.

The cylinder 10 is provided in the form of a hollow cylindrical tube with both sides blocked, and one side has an intake port 11 for exhausting air inside and an exhaust port 12 for intake air from the outside. are provided, respectively, and each intake port 11 and exhaust port 12 have a configuration in which a check valve 13 is installed.

On the other hand, the check valve 13 is an element that allows air to flow in only one direction, and the check valve installed in the intake port 11 maintains an open state when air is sucked in from the outside and allows air inside. is closed so that it does not leak to the outside, and the check valve installed in the exhaust port 12 opens the conduit so that the air inside can be discharged to the outside, and on the contrary, acts to block the inflow of outside air. That is, since this check valve 13 is implemented by a known technique, a detailed description thereof will be omitted.

In addition, the cylinder 10 has a chamber 15 provided in a space on one side where the intake port 11 and the exhaust port 12 are connected, and a motor 20 is installed on one side of the chamber 15. At this time, the rotating shaft 21 of the motor 20 is disposed to cross the inner center of the cylinder 10, and both ends can rotate with shaft bearings 22 at the center of both sides of the cylinder 10. It is a well-supported configuration. If it is not necessary to support rotation of both ends of the motor 20, it may be provided with a configuration in which only one end protruding and extending from the motor 20 is rotatably supported by the shaft bearing 22.

In addition, on one side of the inner surface of the cylinder 10, a fixing protrusion 14 is slid into the contour groove 41 of the cylindrical cam 40 to be described later and induces displacement in the axial direction when the cylindrical cam 40 rotates. is protruded, and at this time, the fixing protrusion 14 has a curved end or a Teflon coating to reduce frictional resistance when inserted into the contour groove 41.

The cylinder 10 of this configuration is provided as a metal tube as a whole, and a motor 20 is installed on one side of the inside, and a cylindrical cam 40, a plunger 50, and a chamber 15 are located on one side of the motor 20. It is a composition that becomes

The motor 20 is a driving source for driving and rotating the rotating shaft 21 in one direction by receiving power from the outside, and is configured to be fixedly installed on one side of the inside of the cylinder 10 . The rotating shaft 21 of the motor 20 is configured to be disposed across the center of the cylinder 10, and both ends are rotatably supported by shaft bearings 22.

The one-way shaft 30 is an element capable of sliding in the axial direction while rotating in one direction by being shaft-fitted to the outer surface of the rotation shaft 21. That is, the one-way shaft 30 applies the principle of a bearing called a well-known one-way bearing or ratchet bearing, and when the rotation shaft 21 rotates in one direction while being fitted to the rotation shaft 21, it interlocks in the same direction. It rotates, and in particular, it is provided to have a linear displacement along the axis of the rotation shaft 21.

As such a one-way shaft 30, a well-known thrust one-way bearing or a linear rotary oilless bearing may be used, so detailed description thereof will be omitted.

The cylindrical cam 40 is a member having a cylindrical shape that is coupled to the outer surface of the one-way shaft 30 and rotates in conjunction with it, and is provided with a reduced diameter while forming a concentric circle inside the cylinder 10.

The cylindrical cam 40 has a configuration in which a contour groove 41 is formed along the outer surface to insert a fixing protrusion 14 protruding from the inside of the cylinder 10, and the contour groove 41 at this time is shown in the drawing As shown, the plunger 50 has a displacement in the axial direction and has a closed curve shape, and according to the displacement width, the plunger 50, which will be described later, compresses and expands the space of the chamber 15.

This cylindrical cam 40 is configured to be assembled by coupling a key 49 with respect to the one-way shaft 30.

The plunger 50 is a movable member having rotation and linear displacement for forming a chamber 15 in the inner space of the cylinder 10 on one side of the cylindrical cam 40, and the outer surface is the inner surface of the cylinder 10. It is an element that slides close to the wall and changes the volume in the chamber 15.

In addition, the plunger 50 is fitted into the one-way shaft 30 and interlocks integrally to have rotational displacement and linear displacement, and a ring-shaped gasket 51 for airtightness is configured on the outer surface of the chamber 15 ) to seal the space within.

As shown in FIGS. 3 and 4, the plunger 50 is integrally fitted to the one-way shaft 30 and coupled to the cylindrical cam 40, and when the one-way shaft 30 rotates, The plunger 50 also has a linear displacement by integrally rotating and linear displacement by the fitting structure of the contour groove 41 and the fixing protrusion 14 while the cylindrical cam 40 rotates.

Therefore, the plunger 50 performs a forward movement operation in a direction of reducing the volume of the chamber 15 as shown in FIG.

Meanwhile, a stopper for regulating the linear movement distance of the cylindrical cam 40 may be provided on one or both of the cylinder 10 and the rotating shaft 21, and in the present invention, one end of the rotating shaft 21 It has been suggested that a stopper 23 for regulating the backward movement of the cylindrical cam 40 is configured, but the present invention is not limited thereto, and in order to regulate the linear movement distance of the cylindrical cam 40, the cylinder 10 It is also possible to protrude and form a locking jaw for stopping on the inner wall surface.

The operation of the vehicle NVH reducing cylinder vacuum pump according to the present invention configured as described above is as follows.

When power is applied to the motor 20 installed on one side inside the tubular cylinder 10, the rotation shaft 21 of the motor 20 rotates in one direction, and the rotation shaft 21 of the motor 20 The one-way shaft 30 coupled to the axis rotates in one direction by interlocking.

Subsequently, the cylindrical cam 40 coupled to one side of the one-way shaft 30 rotates in one direction in conjunction with the one-way shaft 30, and at this time, the contour groove formed on the outer surface of the cylindrical cam 40 ( 41) is constrained by the fixing protrusion 14 protruding from the inner surface of the cylinder 10, so that the cylindrical cam 40 moves linearly along the trajectory of the contour groove 41, as shown in FIGS. 3 and 4 will repeat the same condition.

Therefore, the plunger 50, which is integrally provided on one side of the cylindrical cam 40 and has rotation and linear displacement in conjunction with it, acts on the chamber 15 for volumetric displacement and passes through the intake port 11 as shown in FIG. After sucking in external air, the action of compressing the sucked air and exhausting it through the exhaust port 12 is repeated as shown in FIG. 4 .

In the present invention having such a configuration, as the motor 20, the rotary shaft 21, the one-way shaft 30, and the cylindrical cam 40 rotate in one direction by inertial force, impact noise or vibration is generated compared to the conventional technology. In particular, the plunger 50 does not simply compress and restore the inside of the chamber 15 through linear displacement, but has a linear displacement while rotating, thereby reducing frictional resistance against the inner wall surface of the cylinder 10. It can improve operation stability and durability.

On the other hand, the present invention is not limited to the described embodiments, it is possible to change and use the application site, and various modifications and variations can be made without departing from the spirit and scope of the present invention. It is self-evident to those who have knowledge. Therefore, such variations or modifications should fall within the scope of the claims of the present invention.

1: NVH reducing cylinder vacuum pump for vehicles
10: cylinder 11, 12: intake and exhaust ports
13: check valve 14: fixed protrusion
15: chamber 20: motor
21: rotation shaft 22: shaft bearing
23: stopper 30: one-way axis
40: cylindrical cam 41: contour groove
50: plunger 51: gasket
44: key

Claims (3)

A hollow tubular cylinder having a motor unit having a rotation shaft on the other side and forming a chamber having an intake/exhaust port with a check valve installed on one side;
A one-way shaft that is fitted to the outer surface of the rotation shaft and is capable of sliding in an axial direction while rotating in one direction;
A cylindrical cam coupled to the outer surface of the one-way shaft to rotate interlockingly, forming a contour groove on the outer surface and inserting a fixing protrusion protruding from the inside of the cylinder;
A plunger provided on one side of the cylindrical cam to shield the chamber, the outer surface of which slides into close contact with the inner wall surface of the cylinder to change the volume in the chamber; NVH reducing cylinder vacuum pump for vehicles, characterized in that composed. According to claim 1,
The plunger is provided to have a linear displacement while rotating in conjunction with the cylindrical cam, and a gasket is provided on the outer surface of the plunger and is in close contact with the inner wall surface of the cylinder;
A stopper for regulating a linear movement distance of the cylindrical cam is provided on either or both of the cylinder or the rotating shaft;
The fixing protrusion is slidably fitted into the contour groove of the cylindrical cam to induce displacement in the axial direction when the cylindrical cam rotates, and an end thereof is curved or coated with Teflon to reduce frictional resistance. Reduced cylinder vacuum pump. According to claim 1,
The rotating shaft is axially disposed across the inner center of the cylinder, but both ends are rotatably supported by shaft bearings on both sides of the cylinder;
The NVH reducing cylinder vacuum pump for vehicles, characterized in that the one-way shaft rotates in one direction with respect to the rotation shaft while regulating reverse rotation and is a linear rotary oilless bearing capable of axial movement.

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