WO2015060030A1 - Electrically driven vacuum pump - Google Patents

Abstract

The electrically driven vacuum pump of one embodiment of the present invention comprises: a pump section for generating negative pressure by sucking and discharging fluid; a case for housing the pump section; and a lid member for closing the case. The lid member is provided with a silencer section which is a space formed within the lid member and which connects to the discharge opening of the pump section, the discharge opening discharging the fluid; a lid-member suction opening which sucks in the fluid; and a lid-member cylindrical section which is formed extending from a portion around the lid-member suction opening to the pump section side. The pump section is provided with a pump-section suction opening for sucking the fluid, which is sucked in at the lid-member suction opening, into a pump chamber; and a pump-section cylindrical section formed extending from a portion around the pump-section suction opening to the lid member side. The lid-member cylindrical section and the pump-section cylindrical section are fitted to each other.

Description

Electric vacuum pump

The present invention relates to an electric vacuum pump that generates negative pressure used in a brake booster of a vehicle such as an automobile.

Automotive brake devices are equipped with a brake booster that amplifies the braking force using the intake pipe negative pressure of the engine. In recent years, pumping loss has been reduced due to the demand for low fuel consumption, and therefore the intake pipe negative pressure tends to decrease. Further, in the case of a hybrid vehicle, an electric vehicle, or a vehicle with an idling stop function, the engine intake pipe negative pressure may not be obtained.

Therefore, the negative pressure supplied to the brake booster is generated using an electric vacuum pump. Even in a vehicle equipped with a diesel engine that does not generate intake pipe negative pressure, negative pressure is generated using an electric vacuum pump.

Here, regarding a vacuum pump, for example, Patent Document 1 discloses a silencer for a vacuum pump. And the silencer of the vacuum pump of patent document 1 is trying to reduce the noise of the gas discharged | emitted from a vacuum pump efficiently, since the exhaust port of the silencer is open | released by external air.

Further, for example, the pump of Patent Document 2 includes a columnar motion member that moves eccentrically in the internal space of the case, a lid that has two fluid ports and closes the internal space of the case, and an eccentric motion of the motion member And a deformable member that is deformed along with. The deformable member forms a pump space around the motion member whose volume changes with the eccentric motion of the motion member.

JP 2001-289167 A Japanese Patent Laid-Open No. 9-296784

As described above, in the silencer of the vacuum pump of Patent Document 1, the exhaust port of the silencer is open to the outside air. However, when a vacuum pump is used in a brake booster of a vehicle such as an automobile, the exhaust port of the silencer is connected to the engine intake system in order to obtain the assist of the negative pressure generated by the suction action in the engine intake system. It can also be considered. If it does so, since the inside of a silencer will become a negative pressure, there exists a possibility that the housing, a cover member, etc. which form a silencer may change, or durability may fall. In particular, when a housing, a lid member, and the like that form the silencer are formed of resin, the housing, the lid member, and the like that form the silencer are more easily deformed.

Moreover, since the pump of patent document 2 is not provided with the noise reduction function which suppresses the noise which generate | occur | produces when the fluid (for example, air) in pump space is discharged from a port, an operating noise will become large. .

Then, this invention was made | formed in order to solve the above-mentioned problem, and it aims at providing the electric vacuum pump which can improve the intensity | strength of the cover member provided with the interior space for obtaining a silencing effect. To do.

One aspect of the present invention made to solve the above problems includes a pump section that generates negative pressure by suction and discharge of fluid, a case that houses the pump section, and a lid member that closes the case. In the electric vacuum pump, the lid member is an inner space of the lid member, which is a silencer portion communicating with the fluid discharge port in the pump portion, a lid member suction port for sucking the fluid, and the lid A cylindrical lid member cylindrical portion formed on the pump portion side from a portion around the member inlet, and the pump portion sucks the fluid sucked in the lid member inlet into the pump chamber And a pump part cylindrical part formed on the lid member side from a portion around the pump part suction port, the lid member cylindrical part and the pump part cylinder The shape part is fitted That you are, characterized by.

According to this aspect, even if a pressure change occurs inside the silencer portion, the lid member is difficult to deform due to the portion where the lid member cylindrical portion and the pump portion cylindrical portion are fitted. Therefore, it is possible to improve the strength of the lid member provided with the silencer portion that is an internal space for obtaining a silencing effect.

Also, since the lid member cylindrical portion and the pump portion cylindrical portion are in contact, the heat generated in the pump portion is transferred from the pump portion cylindrical portion to the lid member via the lid member cylindrical portion. And released from the lid member. Therefore, the heat dissipation of the electric vacuum pump is improved.

In the above aspect, it is preferable that the pump portion tubular portion is inserted inside the inner peripheral surface of the lid member tubular portion.

According to this aspect, the strength of the lid member can be improved more reliably.

In the above aspect, it is preferable that the lid member cylindrical portion is inserted inside the inner peripheral surface of the pump portion cylindrical portion.

According to this aspect, the strength of the lid member can be improved more reliably.

In the above aspect, the ring-shaped elastic member between the lid member tubular portion and the pump portion tubular portion in the radial direction at the fitting portion between the lid member tubular portion and the pump portion tubular portion. Is preferably arranged.

According to this aspect, the joining state of the lid member cylindrical portion and the pump portion cylindrical portion is ensured via the ring-shaped elastic member. Therefore, the airtightness between the lid member tubular portion and the pump portion tubular portion is ensured.

In said aspect, it is preferable that the said cover member cylindrical part and the said pump part cylindrical part are couple | bonded by press injection in the fitting part of the said cover member cylindrical part and the said pump part cylindrical part. .

According to this aspect, the joined state of the lid member cylindrical portion and the pump portion cylindrical portion is ensured at the portion where the lid member cylindrical portion and the pump portion cylindrical portion are joined by press fitting. Therefore, the airtightness between the lid member tubular portion and the pump portion tubular portion is ensured.

In the above aspect, the lid member communicates with the silencer portion, discharges the fluid discharged from the discharge port to the outside of the silencer portion, and the discharge port and the discharge port in the silencer portion. A plate-like member disposed between the outlet and projecting toward the pump unit, the plate-like member having an inner space in which the both ends of the plate-like member form the internal space of the lid member. It is preferable that the lid member is formed integrally with the peripheral surface.

According to this aspect, the cross-sectional area of the passage of the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member is temporarily reduced by the plate member. Therefore, the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member is compressed or expanded, so that a load is repeatedly applied. Thereby, noise generated when fluid is discharged from the discharge port of the pump unit is reduced. Therefore, since the silencing performance in the silencer can be improved, the operating sound of the electric vacuum pump can be reduced.

The plate member is formed integrally with the lid member so that both end portions of the plate member are joined to the inner peripheral surface of the lid member, and thus functions as a rib (reinforcement portion) of the lid member. . Therefore, the plate-like member can improve the strength of the lid member. Further, the filter can be fixed at a predetermined position in the vicinity of the inlet of the outlet while being guided by the plate-like member while preventing the foreign matter from entering the outlet, so that the filter can be easily assembled.

In the above aspect, it is preferable that the plate-like member includes an opening penetrating between the discharge port side and the discharge port side.

According to this aspect, the opening of the plate member functions to reduce the cross-sectional area of the fluid passage. Therefore, the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member passes through the opening of the plate-like member, and is once compressed and then expanded, so that a load is applied. Therefore, the silencing performance in the silencer part can be further improved.

In the above aspect, it is preferable that a plurality of the plate-like members are arranged, and the positions of the openings of the plate-like members facing each other are different from each other in the plate-like member.

According to this aspect, in the plate-like members facing each other, the fluid passage passing through the opening is formed in a labyrinth structure. Therefore, the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member receives resistance by passing through the opening. Therefore, the silencing performance in the silencer part can be further improved.

In the above aspect, it is preferable that at least a part of the end face of the plate-like member on the pump part side is in contact with the pump part.

According to this aspect, the heat generated in the pump part is transmitted to the lid member via the plate-like member and then released to the outside from the lid member. Therefore, heat dissipation is improved. Therefore, the durability of the electric vacuum pump is improved.

In said aspect, the said pump part is provided with the pump part plate-shaped member formed so that it may protrude in the said cover member side, The said plate-shaped member with which the said cover member is equipped in the said silencer part, and the said pump part It is preferable that the pump part plate members provided are alternately arranged.

According to this aspect, the passage of the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member is formed in a labyrinth structure. Therefore, the fluid is subjected to resistance. Therefore, the silencing performance in the silencer part can be further improved.

In the above aspect, the plate-like member is disposed so as to surround at least a part of the discharge port, and the filter that prevents foreign matter from entering the discharge port is provided in the vicinity of the inlet of the discharge port. It is preferable that they are arranged while being held in place.

According to this aspect, the filter is held at a predetermined position while being guided by the plate-like member. Therefore, the assembling property of the filter is improved.

Another aspect of the present invention, which has been made to solve the above problems, includes a pump unit that generates negative pressure by suction and discharge of a fluid, a case that houses the pump unit, and a lid member that closes the case. In the electric vacuum pump, the lid member is an internal space of the lid member and communicates with the fluid discharge port in the pump unit, and communicates with the silencer unit and is discharged from the discharge port. A discharge port for discharging the fluid to the outside of the silencer unit, and a plate-like member formed between the discharge port and the discharge port in the silencer unit so as to protrude toward the pump unit side, The plate-like member is formed integrally with the lid member such that both end portions of the plate-like member are joined to an inner peripheral surface forming the internal space in the lid member; And features.

According to this aspect, the cross-sectional area of the passage of the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member is temporarily reduced by the plate member. Therefore, the fluid flowing from the discharge port of the pump unit to the discharge port of the lid member is compressed or expanded, so that a load is repeatedly applied. Thereby, noise generated when fluid is discharged from the discharge port of the pump unit is reduced. Therefore, since the silencing performance in the silencer can be improved, the operating sound of the electric vacuum pump can be reduced.

The plate member is formed integrally with the lid member so that both end portions of the plate member are joined to the inner peripheral surface of the lid member, and thus functions as a rib (reinforcement portion) of the lid member. . Therefore, the plate-like member can improve the strength of the lid member. Further, the filter can be fixed at a predetermined position in the vicinity of the inlet of the outlet while being guided by the plate-like member while preventing the foreign matter from entering the outlet, so that the filter can be easily assembled.

According to the electric vacuum pump of this configuration, it is possible to improve the strength of the lid member having an internal space for obtaining a silencing effect.

It is a figure showing the schematic structure of the brake system containing the electric vacuum pump concerning an embodiment. It is a block diagram which shows the control system of the brake system containing the electric vacuum pump which concerns on embodiment. It is sectional drawing of the electric vacuum pump of Example 1. FIG. In Example 1, it is sectional drawing to which the periphery of the suction port of an upper cover and the suction inlet of a pump part was expanded. In Example 2, it is sectional drawing to which the periphery of the suction port of an upper cover and the suction port of a pump part was expanded. In Example 3, it is sectional drawing to which the periphery of the suction port of an upper cover and the suction port of a pump part was expanded. In Example 4, it is sectional drawing to which the periphery of the suction port of an upper cover and the suction inlet of a pump part was expanded. It is sectional drawing of the electric vacuum pump of Example 5. FIG. FIG. 9 is a cross-sectional view taken along the line AA in FIG. It is a front view of the guide of Example 6. FIG. 10 is a front view of a guide according to a modification of Example 6. It is a front view of the guide of Example 7. It is a front view of the guide of Example 7. It is sectional drawing of the periphery of the pump part and upper cover in the electric vacuum pump of Example 8. It is sectional drawing of the periphery of the pump part and upper cover in the electric vacuum pump of Example 9.

Hereinafter, embodiments of the electric vacuum pump of the present invention will be described in detail with reference to the drawings. In the present embodiment, a case where the electric vacuum pump of the present invention is applied to a brake system will be described.

Therefore, first, the brake system will be described with reference to FIGS. Drawing 1 is a figure showing the schematic structure of the brake system containing the electric vacuum pump concerning an embodiment. FIG. 2 is a block diagram showing a control system of the brake system including the electric vacuum pump according to the embodiment.

As shown in FIGS. 1 and 2, the brake system 1 according to the present embodiment includes a brake pedal 10, a brake booster 12, a master cylinder 14, a negative pressure sensor 16, and an electric vacuum pump 18 ( VP), a first check valve 20, a second check valve 22, an ECU 24, an intake pipe pressure detecting means 26, and the like.

The brake booster 12 is provided between the brake pedal 10 and the master cylinder 14 as shown in FIG. The brake booster 12 generates an assist force with a predetermined boost ratio with respect to the depression force of the brake pedal 10.

The inside of the brake booster 12 is partitioned by a diaphragm (not shown), and a negative pressure chamber (not shown) partitioned on the master cylinder 14 side and a variable pressure chamber (not shown) capable of introducing the atmosphere. Is provided. The negative pressure chamber of the brake booster 12 is connected to the intake pipe 32 of the engine via the first passage L1. That is, the first passage L <b> 1 is connected to the negative pressure chamber of the brake booster 12 and the intake pipe 32. Thereby, the negative pressure generated in the intake pipe 32 according to the opening degree of the throttle valve 34 when the engine is driven is supplied to the negative pressure chamber of the brake booster 12 through the first passage L1.

The master cylinder 14 increases the hydraulic pressure of the brake body (not shown) by the operation of the brake booster 12, and generates a braking force in the brake body. The negative pressure sensor 16 detects the negative pressure in the negative pressure chamber of the brake booster 12.

The electric vacuum pump 18 is connected to the second passage L2 as shown in FIG. That is, the suction port 151 of the electric vacuum pump 18 is connected to the negative pressure chamber of the brake booster 12 via the second passage L2 and the first passage L1. The discharge port 152 of the electric vacuum pump 18 is connected to the first passage L1 on the intake pipe 32 side from the second check valve 22. Here, the second passage L2 is a passage that branches from the first passage L1 from a position between the first check valve 20 and the second check valve 22 on the first passage L1.

Further, the electric vacuum pump 18 is connected to the ECU 24 via a relay 36 as shown in FIG. The driving of the electric vacuum pump 18 is controlled by an on / off operation of a relay by the ECU 24.

The first check valve 20 is provided in a position between the branch portion of the first passage L1 and the second passage L2 and the brake booster 12. The second check valve 22 is located on the intake pipe 32 side with respect to the first check valve 20 in the first passage L1 and between the branch portion of the second passage L2 and the intake pipe 32. Is provided. Both the first check valve 20 and the second check valve 22 are configured to be opened only when the negative pressure on the intake pipe 32 side is higher than the negative pressure on the negative pressure chamber side of the brake booster 12. Only the flow of fluid from the negative pressure chamber side of the brake booster 12 to the intake pipe 32 side is allowed. In this way, the brake system 1 can contain negative pressure in the negative pressure chamber of the brake booster 12 by the first check valve 20 and the second check valve 22.

The ECU 24 is configured by, for example, a microcomputer, and includes a ROM for storing a control program, a readable / writable RAM for storing calculation results, a timer, a counter, an input interface, and an output interface. As shown in FIG. 2, the ECU 24 is connected to a negative pressure sensor 16, an electric vacuum pump 18, an intake pipe pressure detecting means 26, a relay 36, and the like.

Next, the electric vacuum pump 18 will be described.

<Example 1>
The electric vacuum pump 18 has a cylindrical shape, and as shown in FIG. 3, a suction port 151 and a discharge port 152 are provided at the upper end thereof. The electric vacuum pump 18 includes a motor unit 110, a pump unit 120, a bearing 130, a resin case 140, a resin upper lid 150, a resin lower lid 160, and the like. As shown in FIG. 3, the motor unit 110 and the pump unit 120 are arranged in the internal space of the case 140. The case 140 is closed by the upper lid 150 and the lower lid 160.

The motor unit 110 includes an electric motor 112, a commutator (commutator) 113, a metal motor case 114, a brush 115, a shaft 116, and the like. The electric motor 112 is accommodated in a motor case 114, and includes an armature (rotor) 112a and a magnet (stator) 112b. The magnet 112b is fixed to the motor case 114. The armature 112a is disposed inside the magnet 112b so as to be rotatable with a gap. The shaft 116 is integrally attached to the armature 112a and the commutator 113.

In the motor unit 110, the electric motor 112 is driven by an external power source, and the shaft 116 is rotationally driven. The shaft 116 is rotatably supported by a bearing 130 fixed to the motor case 114.

The commutator 113 is attached to the shaft 116. The brush 115 is disposed outside the outer peripheral surface of the commutator 113. The brush 115 is energized while being in sliding contact with the commutator 113 relatively.

The pump unit 120 is constituted by a vane type vacuum pump, and is disposed in an upper part of the motor unit 110 in the case 140. The pump unit 120 is driven in conjunction with the motor unit 110. Here, the vane type vacuum pump has a structure in which a groove is formed in a rotor arranged eccentrically in a cylindrical pump chamber, and a plurality of vanes are inserted in the groove so as to be movable in the rotor radial direction. is doing. When the rotor rotates, the vane protrudes from the groove by centrifugal force, and the vane comes into sliding contact with the peripheral surface of the pump chamber. At the same time, the volume of the closed space partitioned by the vanes is increased or decreased to suck, compress, and discharge (discharge) gas (for example, air), and negative pressure is generated in the pump chamber. .

Specifically, the pump unit 120 includes a housing 121 having an inner peripheral surface formed in a substantially cylindrical shape. Note that the substantially cylindrical shape of the inner peripheral surface means that the cross section of the housing 121 is not limited to a true circle or an ellipse, but a circle surrounded by a curve. Both ends of the housing 121 are closed with a circular cover member 122a and a cover member 122b, and a pump chamber 123 is formed by the inner peripheral surface of the housing 121 and the cover member 122a and the cover member 122b. The housing 121 is fixed to the case 140.

A cylindrical rotor 124 is accommodated inside the pump chamber 123 so as to be rotatable about an axis that is eccentric with respect to the central axis of the pump chamber 123. The rotor 124 is connected to the shaft 116 of the electric motor 112. As a result, the rotor 124 rotates in conjunction with the rotational drive of the electric motor 112 via the shaft 116.

And the rotor 124 has a plurality of vane grooves. A vane 125 formed in a flat plate shape is slidably fitted in each vane groove so as to advance and retreat. The end portion of the vane 125 is in sliding contact with the inner peripheral surface of the housing 121 by centrifugal force applied to the vane 125 when the rotor 124 rotates. The upper and lower end surfaces of the vane 125 are in contact with the cover member 122a and the cover member 122b, respectively. In this way, the vane 125 partitions the inside of the pump chamber 123.

The pump chamber 123 communicates with the outside through a suction port 126 and a discharge port 127. The suction port 126 is provided in the cover member 122 a so as to communicate with the pump chamber 123. The suction port 126 is a portion where air outside the pump is drawn into the pump. The discharge port 127 is provided in the cover member 122 a so as to communicate with the pump chamber 123. The exhaust from the discharge port 127 is discharged to the outside of the pump via the discharge port 152.

The bearing 130 is disposed between the motor unit 110 and the pump unit 120. The bearing 130 supports the shaft 116 in a state where the shaft 116 is rotatable.

The upper lid 150 is a resin member that closes the upper open end of the case 140 that houses the motor unit 110 and the pump unit 120. That is, the upper lid 150 closes the case 140 from the pump part side.

The upper lid 150 includes a suction port 151 for sucking air into the pump unit 120 from the outside of the pump, a silencer unit 153 provided with a space communicating with the discharge port 127 of the pump unit 120, and exhaust gas discharged from the pump unit 120. And a discharge port 152 for discharging the gas to the outside of the pump. The upper lid 150 is an example of the “lid member” in the present invention.

And the silencer part 153 is formed in the internal space of the upper lid 150. As a result, the exhaust discharged from the discharge port 127 of the pump unit 120 passes through the silencer unit 153 and then flows through the discharge port 152 and is discharged outside the pump.

The lower lid 160 is a resin member that closes the lower opening end of the case 140 that accommodates the motor unit 110 and the pump unit 120, and closes the case 140 from the motor unit side.

In the electric vacuum pump 18 having such a configuration, when the electric motor 112 is rotationally driven by power supply from the outside, the rotor 124 rotates in conjunction therewith. Then, the vane 125 slides along the vane groove due to the centrifugal force, the end surface of the vane 125 abuts on the inner peripheral surface of the housing 121, and rotates along the inner peripheral surface of the housing 121 while maintaining this state. As the rotor 124 rotates, the volume of each pump chamber 123 is expanded or compressed, so that air is sucked into the pump chamber 123 from the suction port 126 and air in the pump chamber 123 is discharged from the discharge port 127. Is done. By this operation, a negative pressure is created in the pump chamber 123.

In other words, in the brake system 1, the electric vacuum pump 18 starts driving when the relay 36 is turned on based on a drive start signal from the ECU 24, and is driven from the suction port 151 via the second passage L <b> 2 and the first passage L <b> 1. Negative pressure is supplied into the negative pressure chamber of the brake booster 12. Further, the electric vacuum pump 18 stops driving by the relay 36 being turned off based on the drive stop signal from the ECU 24, and the negative pressure of the brake booster 12 is discharged from the suction port 151 through the second passage L2 and the first passage L1. Stop supplying negative pressure into the pressure chamber.

In the brake system 1, when the engine is operating and intake pipe negative pressure is generated, the negative pressure in the intake pipe 32 enters the negative pressure chamber of the brake booster 12 via the first passage L <b> 1. The negative pressure in the negative pressure chamber of the brake booster 12 can be adjusted. Further, when the engine is stopped or when the ECU 24 determines that the negative pressure is insufficient, the ECU 24 turns on the relay to drive the electric vacuum pump 18 to drive the second passage L2 and the first passage L1. The negative pressure in the negative pressure chamber of the brake booster 12 can be adjusted by supplying the negative pressure into the negative pressure chamber of the brake booster 12 via

In this embodiment, as shown in FIGS. 3 and 4, the upper lid 150 includes a suction passage 170 through which air sucked from the suction port 151 flows. The suction passage 170 includes a suction port 172 at an end of the suction passage 170 on the pump unit 120 side. Then, external air is sucked into the electric vacuum pump 18 from the suction port 151 through the suction passage 170 and the suction port 172. The suction port 172 is an example of the “lid member suction port” in the present invention.

The upper lid 150 includes a cylindrical tube portion 174 formed from a portion around the suction port 172 toward the pump portion 120 side. The cylindrical portion 174 is formed in a concave shape so as to open to the pump portion 120 side. The tubular portion 174 is an example of the “lid member tubular portion” in the present invention.

Further, the cover member 122a of the pump unit 120 includes a cylindrical tube portion 176 formed from a portion around the suction port 126 toward the upper lid 150 side. The cylindrical portion 176 is formed in a convex shape (columnar shape) so as to protrude toward the upper lid 150 side. The cylindrical portion 176 includes a suction passage 178 communicating with the suction port 126 inside the inner peripheral surface 176a. The air sucked from the suction port 172 of the upper lid 150 flows toward the suction port 126 through the suction passage 178. The suction port 126 is an example of the “pump portion suction port” in the present invention. The tubular portion 176 is an example of the “pump portion tubular portion” in the present invention.

The cylindrical portion 174 of the upper lid 150 and the cylindrical portion 176 of the pump portion 120 are fitted so that the end on the upper lid 150 side of the cylindrical portion 176 is inserted inside the inner peripheral surface 174a of the cylindrical portion 174. Are combined. Thus, since the cylindrical part 174 and the cylindrical part 176 are fitted, the upper cover 150 will be supported by the cylindrical part 176, and the upper cover 150 becomes difficult to deform | transform. Therefore, even if the inside of the silencer part 153 becomes negative pressure due to the suction action in the intake pipe, the central portion of the upper lid 150 is difficult to be recessed, and the intake port 151 and the exhaust port 152 are difficult to fall inside. Therefore, the durability of the electric vacuum pump 18 is maintained.

Also, an O-ring 180, which is a ring-shaped elastic member, is disposed between the tubular portion 174 and the tubular portion 176 in the radial direction at the fitting portion between the tubular portion 174 and the tubular portion 176. That is, the O-ring 180 is inserted between the inner peripheral surface 174a of the cylindrical portion 174 and the outer peripheral surface 176b of the cylindrical portion 176 into a groove formed on the outer peripheral surface 176b of the cylindrical portion 176. Have been placed. Thereby, the joining state of the cylindrical part 174 and the cylindrical part 176 is ensured via the O-ring 180 in the radial direction of the electric vacuum pump 18 (left-right direction in FIG. 4). Therefore, the airtightness between the cylindrical part 174 and the cylindrical part 176 is ensured.

As described above in detail, in the present embodiment, the upper lid 150 includes the silencer 153 that is an internal space of the upper lid 150 and communicates with the air discharge port 127 in the pump unit 120, and the air for sucking air. The pump unit 120 includes a suction port 172 and a cylindrical tube part 174 formed on the pump unit 120 side from a portion around the suction port 172, and the pump unit 120 supplies air sucked through the suction port 172 to the pump unit 120. A suction port 126 for sucking into the pump chamber 123, and a cylindrical cylindrical portion 176 formed on the upper lid 150 side from a portion around the suction port 126, the cylindrical portion 174 and the cylindrical portion 176. Are fitted.

Thereby, even if a pressure change occurs inside the silencer part 153, such as when the inside of the silencer part 153 becomes a negative pressure, the tubular part 174 and the tubular part 176 are fitted. Since it is supported by 176, the upper lid 150 is difficult to deform. Therefore, the strength of the upper lid 150 including the silencer portion 153 can be improved.

Further, since the cylindrical portion 174 and the cylindrical portion 176 are in contact with each other, the heat generated in the pump portion 120 is transferred from the cylindrical portion 176 to the upper lid 150 via the cylindrical portion 174, and then the upper lid 150. Released from. Therefore, the heat dissipation of the electric vacuum pump 18 is improved.

<Example 2>
Next, the second embodiment will be described. The same components as those of the first embodiment are denoted by the same reference numerals, the description thereof will be omitted, and different points will be mainly described.

In this embodiment, as shown in FIG. 5, the end portion on the upper lid 150 side of the cylindrical portion 176 of the pump portion 120 is press-fitted inside the inner peripheral surface 174 a of the cylindrical portion 174 of the upper lid 150. In this way, at the fitting portion between the cylindrical portion 174 and the cylindrical portion 176, the cylindrical portion 174 and the cylindrical portion 176 are joined by press-fitting. As a result, the tubular portion 174 and the tubular portion 176 are joined by press-fitting with the tubular portion 174 in the axial direction and the radial direction of the electric vacuum pump 18 (vertical direction and lateral direction in FIG. 5). The joining state of the cylindrical part 176 is ensured. Therefore, the airtightness between the cylindrical part 174 and the cylindrical part 176 is ensured.

<Example 3>
Next, the third embodiment will be described. Components that are the same as those in the first and second embodiments are denoted by the same reference numerals, description thereof will be omitted, and different points will be mainly described.

In the present embodiment, as shown in FIG. 6, the upper lid 150 includes a cylindrical cylindrical portion 182 formed from a portion around the suction port 172 toward the pump portion 120 side. The cylindrical portion 182 is formed in a convex shape (columnar shape) so as to protrude toward the pump portion 120 side. The cylindrical portion 182 includes a suction passage 184 communicating with the suction port 172 inside the inner peripheral surface 182a. The air sucked from the suction port 172 flows through the suction passage 184 toward the suction port 126 of the pump unit 120. The cylindrical portion 182 is an example of the “lid member cylindrical portion” in the present invention.

Further, the cover member 122a of the pump unit 120 includes a cylindrical cylindrical portion 186 formed from a portion around the suction port 126 toward the upper lid 150 side. The cylindrical portion 186 is formed in a concave shape so as to open to the upper lid 150 side. The tubular portion 186 is an example of the “pump portion tubular portion” in the present invention.

The cylindrical part 182 of the upper lid 150 and the cylindrical part 186 of the pump part 120 are fitted so that the cylindrical part 182 is inserted inside the inner peripheral surface 186a of the cylindrical part 186. Thus, since the cylindrical part 182 and the cylindrical part 186 are fitted, the upper cover 150 will be supported by the cylindrical part 186, and the upper cover 150 becomes difficult to deform | transform. Therefore, even if the inside of the silencer part 153 becomes negative pressure due to the suction action in the intake pipe, the central portion of the upper lid 150 is difficult to be recessed, and the intake port 151 and the exhaust port 152 are difficult to fall inside. Therefore, the durability of the electric vacuum pump 18 is maintained.

Also, an O-ring 180, which is a ring-shaped elastic member, is disposed between the tubular portion 182 and the tubular portion 186 in the radial direction at the fitting portion between the tubular portion 182 and the tubular portion 186. That is, the O-ring 180 is inserted into a groove formed on the inner peripheral surface 186 a of the cylindrical portion 186 between the outer peripheral surface 182 b of the cylindrical portion 182 and the inner peripheral surface 186 a of the cylindrical portion 186. Arranged. Thereby, the joining state of the cylindrical part 182 and the cylindrical part 186 is ensured via the O-ring 180 in the radial direction of the electric vacuum pump 18 (left and right direction in FIG. 6). Therefore, the airtightness between the cylindrical part 182 and the cylindrical part 186 is ensured.

<Example 4>
Next, the fourth embodiment will be described. The same components as those in the first to third embodiments are denoted by the same reference numerals, the description thereof will be omitted, and different points will be mainly described.

In this embodiment, as shown in FIG. 7, the cylindrical portion 182 of the upper lid 150 is press-fitted inside the inner peripheral surface 186a of the cylindrical portion 186 of the cover member 122a. In this way, the tubular portion 182 and the tubular portion 186 are joined by press fitting at the fitting portion between the tubular portion 182 and the tubular portion 186. As a result, the cylindrical portion 182 in the axial direction and the radial direction (vertical direction and horizontal direction in FIG. 7) of the electric vacuum pump 18 at the portion where the cylindrical portion 182 and the cylindrical portion 186 are joined by press-fitting. And the joining state of the cylindrical part 186 is ensured. Therefore, the airtightness between the cylindrical part 182 and the cylindrical part 186 is ensured.

<Example 5>
Next, the fifth embodiment will be described. The same components as those in the first to fourth embodiments are denoted by the same reference numerals, the description thereof will be omitted, and different points will be mainly described. In this embodiment, the exhaust from the discharge port 127 is discharged to the outside of the pump through the exhaust port 156 (see FIG. 8) formed in the upper lid 150 and the discharge port 152. The exhaust port 156 is an example of the “exhaust port” in the present invention.

In the present embodiment, as shown in FIGS. 8 and 9, the upper lid 150 is provided with a guide 190 (190 </ b> A, 190 </ b> B, 190 </ b> C, 190 </ b> D) disposed between the discharge port 127 and the exhaust port 156 inside the silencer portion 153. , 190E). The guide 190 is formed in a plate shape, and is formed so as to protrude from the surface 158 of the upper lid 150 to the pump unit 120 side. In the example shown in FIG. 9, the guide 190A and the guide 190B are formed in the vertical direction of FIG. 9, and the guide 190C, the guide 190D, and the guide 190E are formed in the horizontal direction of FIG.

The end portion 190 a and the end portion 190 b in the longitudinal direction (vertical direction or left-right direction in FIG. 9) of the guide 190 are joined to the inner peripheral surface 154 that forms the silencer portion 153 in the upper lid 150. That is, the guide 190 is formed integrally with the upper lid 150 so that the end portion 190 a and the end portion 190 b of the guide 190 are joined to the inner peripheral surface 154 of the upper lid 150.

The guide 190 divides the passage while forming a gap δ (see FIG. 8) with the cover member 122a of the pump unit 120 in the middle of the passage of air flowing from the discharge port 127 to the exhaust port 156. Is formed. In other words, the guide 190 is formed so as to temporarily reduce the cross-sectional area of the passage of the air flowing from the discharge port 127 to the exhaust port 156.

In FIG. 9, five guides 190 are provided as an example in FIG. 9, but the number is not particularly limited, and only one guide may be formed or a plurality of guides 190 may be formed. The guide 190 is an example of the “plate member” in the present invention.

In this way, the guide 190 forms a plurality of spaces partitioned inside the silencer portion 153 while communicating with each other. The discharge port 127 and the exhaust port 156 are respectively provided in portions corresponding to different spaces in the space formed by the guide 190. The air that is about to flow from the discharge port 127 toward the exhaust port 156 first hits the surface 158 of the upper lid 150, then passes through the gap δ and flows to the exhaust port 156. In this way, the air that is about to flow from the discharge port 127 toward the exhaust port 156 is reduced in the cross-sectional area of the passage by the guide 190, and thus flows while being repeatedly compressed and expanded. Therefore, air is repeatedly subjected to a load. Therefore, noise generated when air is discharged from the discharge port 127 is reduced. Therefore, the silencer performance is improved in the silencer portion 153.

Further, the end portion 190 a and the end portion 190 b of the guide 190 are joined to the inner peripheral surface 154 of the upper lid 150. Therefore, since the guide 190 functions as a rib of the upper lid 150, when a change in the pressure of the air in the silencer 153 occurs, the deflection of the side surface portion 159 (part having the inner peripheral surface 154 on the inner side) particularly in the upper lid 150. Can be suppressed. Therefore, the guide 190 can improve the strength of the upper lid 150. In particular, since the discharge port 152 is connected to the intake pipe 32, the inside of the silencer part 153 has a negative pressure, but the strength of the upper lid 150 is ensured by the guide 190.

Furthermore, as shown in FIG. 9, the guide 190B, the guide 190C, and the guide 190D are arranged so as to surround at least a part of the exhaust port 156. Thus, the exhaust port 156 is surrounded by the inner peripheral surface 154 of the upper lid 150, the guide 190B, the guide 190C, and the guide 190D. The filter 192 is disposed in a space surrounded by the inner peripheral surface 154 of the upper lid 150, the guide 190B, the guide 190C, and the guide 190D. Accordingly, the filter 192 is disposed at a predetermined position in the vicinity of the inlet of the exhaust port 156 while being held by the inner peripheral surface 154 of the upper lid 150, the guide 190B, the guide 190C, and the guide 190D. Therefore, the assembling property of the filter 192 is improved. The filter 192 is a member that prevents foreign matters (for example, worn pieces of the rotor 124 and the vane 125) that may be generated in the electric vacuum pump 18 from being sucked into the engine from the exhaust port 156.

As described above in detail, in the electric vacuum pump 18 of the present embodiment, the upper lid 150 is disposed between the discharge port 127 and the exhaust port 156 in the silencer unit 153 and protrudes toward the pump unit 120. A guide 190 is formed. The guide 190 is formed integrally with the upper lid 150 such that the end portion 190 a and the end portion 190 b of the guide 190 are joined to the inner peripheral surface 154 of the upper lid 150.

Thereby, the cross-sectional area of the passage of the air flowing from the discharge port 127 to the exhaust port 156 is temporarily reduced by the guide 190. Therefore, the air flowing from the discharge port 127 to the exhaust port 156 is compressed or expanded, and thus a load is repeatedly applied. Thereby, the noise generated when air is discharged from the discharge port 127 is reduced. Therefore, since the silencing performance in the silencer part 153 can be improved, the operating sound of the electric vacuum pump 18 can be reduced.

Further, the guide 190 functions as a rib of the upper lid 150 because the guide 190 is formed integrally with the upper lid 150 so that the end portion 190a and the end portion 190b of the guide 190 are joined to the inner peripheral surface 154 of the upper lid 150. . Therefore, the guide 190 can improve the strength of the upper lid 150. Further, the filter 192 that prevents the entry of foreign matter into the exhaust port 156 can be fixed at a predetermined position near the inlet of the exhaust port 156 while being guided by the guide 190, so that the assembling property of the filter 192 is improved.

<Example 6>
Next, a sixth embodiment will be described. Components that are the same as those in the first to fifth embodiments are denoted by the same reference numerals, a description thereof will be omitted, and different points will be mainly described.

As shown in FIG. 10, the guide 190 of the present embodiment is a diaphragm 194 that is a hole that passes through between the discharge port 127 side and the exhaust port 156 side (between the manual side and the depth side of FIG. 10). Is provided. The restrictor 194 functions to restrict the cross-sectional area of the air passage. For this reason, the air flowing from the discharge port 127 to the exhaust port 156 passes through the throttle 194, and is once compressed and then expanded to be loaded. Therefore, noise generated when air is discharged from the discharge port 127 is further reduced. Therefore, the silencing performance in the silencer part can be further improved.

Further, a modification of the guide 190 as shown in FIG. 11 is also conceivable. As shown in FIG. 11, the guide 190 of the modified example penetrates between the discharge port 127 side and the exhaust port 156 side (between the manual side and the depth side of FIG. 11) instead of the throttle 194. A notched diaphragm 196 is provided.

The diaphragm 194 and the diaphragm 196 are examples of the “opening” in the present invention.

<Example 7>
Next, a description will be given of a seventh embodiment. Components that are the same as those in the first to sixth embodiments are denoted by the same reference numerals, a description thereof is omitted, and different points are mainly described.

As shown in FIGS. 12 and 13, the diaphragms 194 of the guide 190A and the guide 190B facing each other are different in position and number in the vertical and horizontal directions arranged in the guide 190A and the guide 190B. In the example shown in FIGS. 12 and 13, the number of stops 194 in the guide 190A is two, while the number of stops 194 in the guide 190B is one. The diaphragm 194 of the guide 190A is disposed at the position of the upper part and the left and right ends in FIG. 12, while the diaphragm 194 of the guide 190B is disposed at the position of the lower part and center of FIG. In other words, the diaphragms 194 of the guides 194A and 194B facing each other have different relative positions in the guides 190A and 190B. The distance between the diaphragm 194 of the guide 190A and the diaphragm 194 of the guide 190B is preferably as large as possible.

By arranging the throttle 194 in this way, air passages passing through the throttles 194 of the guide 190A and the guide 190B are formed in a labyrinth structure. Therefore, the air flowing from the discharge port 127 to the exhaust port 156 receives resistance when passing through the throttle 194. Therefore, the silencing performance in the silencer unit 153 can be further improved.

<Example 8>
Next, the eighth embodiment will be described. The same components as those in the first to seventh embodiments are denoted by the same reference numerals, the description thereof will be omitted, and different points will be mainly described.

In this embodiment, as shown in FIG. 14, the end surface 191 of the guide 190 on the pump part 120 side is in contact with the cover member 122a of the pump part 120. Thereby, the heat generated in the pump unit 120 is transmitted to the upper lid 150 via the guide 190 and then released to the outside from the upper lid 150. Therefore, heat dissipation is improved. Therefore, the durability of the electric vacuum pump 18 is improved.

Note that the guide 190 includes the diaphragm 194 and the diaphragm 196 described above. In this way, the plurality of spaces formed inside the silencer part 153 by the guide 190 communicate with each other by the diaphragm 194 and the diaphragm 196.

Further, in the example shown in FIG. 14, the entire end surface 191 of the guide 190 is in contact with the pump unit 120, but is not limited to this, and at least a part of the end surface 191 of the guide 190 is in contact with the pump unit 120. Just do it.

<Example 9>
Next, the ninth embodiment will be described. The same components as those in the first to eighth embodiments are denoted by the same reference numerals, the description thereof will be omitted, and different points will be mainly described.

15, the cover member 122a of the pump unit 120 according to the present embodiment includes a guide 198 formed so as to protrude toward the upper lid 150 in the silencer unit 153. In the silencer portion 153, guides 190 and guides 198 are alternately arranged between the discharge port 127 and the exhaust port 156.

Thereby, the passage of the air flowing from the discharge port 127 to the exhaust port 156 is formed in a labyrinth structure. Therefore, the air flowing from the discharge port 127 to the exhaust port 156 receives resistance by passing through a passage formed in the labyrinth structure. Therefore, the silencing performance in the silencer part 153 is further improved. The guide 198 is an example of the “pump part plate member” in the present invention.

It should be noted that the above-described embodiment is merely an example, and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention.

For example, embodiments in which the embodiments of Embodiments 1 to 9 are combined in various combinations are also conceivable.

DESCRIPTION OF SYMBOLS 1 Brake system 12 Brake booster 18 Electric vacuum pump 110 Motor part 112 Electric motor 120 Pump part 122a Cover member 126 Suction port 127 Ejection port 140 Case 150 Upper lid 151 Suction port 153 Silencer unit 156 Exhaust port 170 Suction passage 172 Suction port 174 Tubular Portion 174a Inner peripheral surface 176 Tubular portion 176a Inner peripheral surface 176b Outer peripheral surface 178 Suction passage 180 O-ring 182 Tubular portion 182a Inner peripheral surface 182b Outer peripheral surface 184 Suction passage 186 Tubular portion 186a Inner peripheral surfaces 190, 190A, 190B, 190C, 190D, 190E Guide 190a End 190b End 191 End 192 Filter 194 Diaphragm 196 Diaphragm 198 Guide δ Clearance

Claims (12)

In an electric vacuum pump having a pump part that generates negative pressure by suction and discharge of fluid, a case that houses the pump part, and a lid member that closes the case,
The lid member is an inner space of the lid member and communicates with the fluid discharge port in the pump unit, a lid member suction port for sucking the fluid, and a periphery of the lid member suction port A cylindrical lid member cylindrical part formed on the pump part side from the part,
The pump portion includes a pump portion suction port for sucking the fluid sucked in the lid member suction port into a pump chamber, and a cylinder formed on the lid member side from a portion around the pump portion suction port. A pump-shaped cylindrical part,
The lid member tubular part and the pump part tubular part are fitted,
Electric vacuum pump characterized by The electric vacuum pump according to claim 1,
The pump part cylindrical part is inserted inside the inner peripheral surface of the lid member cylindrical part;
Electric vacuum pump characterized by The electric vacuum pump according to claim 1,
The lid member tubular portion is inserted inside the inner peripheral surface of the pump portion tubular portion;
Electric vacuum pump characterized by The electric vacuum pump according to any one of claims 1 to 3,
A ring-shaped elastic member is disposed between the lid member tubular portion and the pump portion tubular portion in the radial direction at the fitting portion between the lid member tubular portion and the pump portion tubular portion. ,
Electric vacuum pump characterized by The electric vacuum pump according to any one of claims 1 to 3,
The lid member tubular part and the pump part tubular part are joined by press fitting at the fitting part of the cover member tubular part and the pump part tubular part,
Electric vacuum pump characterized by The electric vacuum pump according to any one of claims 1 to 5,
The lid member communicates with the silencer portion and is disposed between the discharge port and the discharge port within the silencer portion, and a discharge port for discharging the fluid discharged from the discharge port to the outside of the silencer portion. And a plate-like member formed so as to protrude toward the pump part side,
The plate-like member is formed integrally with the lid member such that both end portions of the plate-like member are joined to an inner peripheral surface forming the internal space in the lid member;
Electric vacuum pump characterized by The electric vacuum pump according to claim 6,
The plate-like member includes an opening penetrating between the discharge port side and the discharge port side;
Electric vacuum pump characterized by The electric vacuum pump according to claim 7,
A plurality of the plate-like members are arranged,
The opening portions of the plate-like members facing each other are arranged at different positions in the plate-like member,
Electric vacuum pump characterized by The electric vacuum pump according to any one of claims 6 to 8,
At least a part of an end surface of the plate-like member on the pump part side is in contact with the pump part;
Electric vacuum pump characterized by The electric vacuum pump according to any one of claims 6 to 9,
The pump part includes a pump part plate member formed to protrude toward the lid member side,
In the silencer part, the plate member provided in the lid member and the pump part plate member provided in the pump part are alternately arranged,
Electric vacuum pump characterized by The electric vacuum pump according to any one of claims 6 to 10,
The plate-like member is arranged so as to surround at least a part of the discharge port,
The filter that prevents foreign matter from entering the discharge port is disposed while being held by the plate-like member in the vicinity of the inlet of the discharge port,
Electric vacuum pump characterized by In an electric vacuum pump having a pump part that generates negative pressure by suction and discharge of fluid, a case that houses the pump part, and a lid member that closes the case,
The lid member is an inner space of the lid member and communicates with the fluid discharge port of the pump unit, and communicates with the silencer unit and discharges the fluid discharged from the discharge port of the silencer unit. A discharge port that discharges to the outside, and a plate-like member that is arranged between the discharge port and the discharge port in the silencer portion and is formed to protrude toward the pump portion side,
The plate-like member is formed integrally with the lid member such that both end portions of the plate-like member are joined to an inner peripheral surface forming the internal space in the lid member;
Electric vacuum pump characterized by

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