JP6074139B2 - Negative pressure pump - Google Patents

Description

  The present invention relates to a negative pressure pump, for example, a negative pressure pump that makes negative pressure in a negative pressure chamber of a negative pressure booster provided in a vehicle.

  As this type of negative pressure pump, a negative pressure pump for vehicles has been proposed (see, for example, Patent Document 1 (FIG. 2)).

The technique of this patent document 1 is demonstrated below based on drawing.
FIG. 20 is an exploded perspective view of a conventional negative pressure pump. In the negative pressure pump 200, a pump portion 204 driven by a motor 203 is mounted on one side surface 202 of a body portion 201, and the pump portion 204 is attached to a cover body 205. The cover body 205 is attached to one side surface 202.

  In the negative pressure pump 200, when the pump unit 204 is driven by the motor 203, the periphery of the motor shaft 206 becomes negative pressure. If the pressure around the motor shaft 206 becomes negative, the vicinity of the bearings provided in the motor 203 and the boss 207 is in a vacuum state, which is not preferable.

The vacuum state is eliminated by supplying air to the vicinity of the bearing. Although it is conceivable to provide a through hole in the body part 201 or the motor 203 and supply external air to the vicinity of the bearing, there is a possibility that sewage outside from the through hole may enter the vicinity of the bearing.
Therefore, it is recommended to supply the air in the negative pressure pump 200 to the vicinity of the bearing. Specifically, since the exhaust path in the negative pressure pump 200 is positive pressure, a breathing hole is provided in the exhaust path, and air is supplied to the vicinity of the bearing through the breathing hole.

  By the way, a rotating body (vane or rotor) is built in the pump unit 204, and since this rotating body is in sliding contact with the wall, a slight amount of wear powder is generated. This wear powder may mix with the exhaust and enter the vicinity of the bearing through the breathing hole. Since wear powder causes motor failure, it is necessary to prevent intrusion into the motor.

JP 2010-236503 A

  This invention makes it a subject to provide the negative pressure pump which can suppress that abrasion powder is inhaled in a motor.

According to the first aspect of the present invention, a pump unit that is driven by a motor is mounted on one side surface of the body unit as a base, the pump unit is covered with a cover body, the cover body is mounted on the one side surface, A negative pressure pump provided on one side surface with an exhaust path for exhaust gas exhausted from the pump unit, and provided with a breathing hole for supplying air to the motor to prevent the motor from becoming a vacuum The breathing hole is provided between a communication path that communicates with the exhaust path on one side of the body portion and the shaft hole, and the communication path includes a plurality of barriers that block the flow of air. Is meandering as viewed from the pump side.

According to the first aspect of the present invention, an exhaust passage for exhaust exhausted from the pump portion is provided on one side surface of the body portion, and a breathing hole for supplying air to the motor to prevent the inside of the motor from becoming a vacuum Is provided. This breathing hole is provided between the communication path leading to the exhaust path on one side of the body part and the shaft hole. The communication path includes a plurality of barriers that block air flow, and the communication path is viewed from the pump part side. Meandering.
Since the breathing hole is arranged between the contact path and the shaft hole leading to an exhaust passage on one side of the body portion, rather than the exhaust gas containing wear debris reaches immediately breathing hole, the wear particles in the motor Inhalation can be suppressed. As a result, the durability of the motor can be improved.

In addition, since the barrier is provided in the communication path, the wear powder contained in the exhaust is blocked by the barrier, and the exhaust from which the wear powder has been removed can be guided to the breathing hole.

In addition, since the communication path is meandering, the communication path becomes longer, and wear powder is more efficiently removed.

It is a figure which shows the example of arrangement | positioning of the negative pressure pump which concerns on this invention. It is a perspective view of a negative pressure pump. It is a fragmentary sectional view of a negative pressure pump. It is a disassembled perspective view of a negative pressure pump. It is a disassembled perspective view of a pump part. It is a front view of a negative pressure pump. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. 6. FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 7. FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 7. It is a partial expansion perspective view of a connection path. It is the 11-11 line sectional view of FIG. 12 is a sectional view taken along line 12-12 of FIG. It is a figure explaining the flow of the intake air from a connection pipe to a pump part. It is a figure explaining the flow of the exhaust_gas | exhaustion from a pump part to an exhaust pipe. It is a figure explaining discharge of water generated by dew condensation. It is a figure explaining the flow of the air to a breathing hole. It is a figure explaining the other aspect of FIG. It is a figure explaining the other aspect of FIG. It is a figure explaining the other aspect of FIG. It is a principle diagram of a conventional negative pressure pump.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

First, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the negative pressure pump 10 of the present invention is a kind of vacuum pump that makes negative pressure in a negative pressure chamber 12 of a negative pressure booster 11 provided in a vehicle.
When the negative pressure pump 10 is operated, the negative pressure pipe 13, the negative pressure chamber 12, and the variable pressure chamber 14 are at negative pressure. When the brake pedal 16 is depressed in this state, the negative pressure chamber 12 and the variable pressure chamber 14 are cut off, air is introduced into the variable pressure chamber 14, and the diaphragm 17 is returned to the return spring by the differential pressure between the negative pressure chamber 12 and the variable pressure chamber 14. 18 is deformed to the compression side and push rod 19 is pushed out. As a result, a large braking force can be obtained with a small pedal effort.

The internal structure of the negative pressure pump 10 will be described with reference to FIG. In FIG. 2, the external appearance of the negative pressure pump 10 will be described.
As shown in FIG. 2, a body portion 30 as a base, a cover body 50 is attached to the upper surface of the body portion 30, and a motor 70 is attached to the lower surface of the body portion 30. A connecting pipe 21 for intake is attached to the narrow surface 31 of the body portion 30 with screws 22, and a plurality of (three in this example) arm portions 32 are extended from the body portion 30, and a bush 33 is attached to the arm portion 32. Is fitted. The bush 33 serves as a rubber mount when attached to the vehicle.

Next, the inside of the negative pressure pump 10 will be described.
As shown in FIG. 3, a pump unit 80 that generates a negative pressure is attached to the upper surface of the body unit 30. The pump unit 80 is surrounded by a storage chamber 51 provided in the cover body 50. An inner wall 63 is provided inside the cover body 50, and a space between the inner wall 63 and the outer wall 52 of the cover body is formed as a sound deadening chamber 53.

Next, the structure of the negative pressure pump 10 will be described in detail.
As shown in FIG. 4, the negative pressure pump 10 includes a body portion 30 as a base, and a plurality of (four in this example) provided on the upper surface 34 (one side surface 34 in the present invention) of the body portion 30. The pump portion 80 attached by screwing a long bolt 81 into the female screw hole 35, the connection pipe 21 connected to the suction port (detailed later), the pump portion 80 and the upper surface 34 of the body portion 30 (in the present invention) A cover body 50 attached by screwing screws 54 into a plurality (four in this example) of female screw holes 36 provided on one side surface 34) and a lower surface 37 (the other side surface 37) of the body portion 30 A plurality of (in this example, two) screws 71 are attached, and the motor shaft 72 includes a motor 70 that is an involute spline shaft.

An intermediate connector (reference numeral 73 in FIG. 7) for supplying power to the motor 70 is provided on the side of the motor 70.
Since the body part 30 is a base for mounting the motor 70 and connecting to the vehicle, it is desirable that the body part 30 is made of a metal having a large thickness and rigidity, such as a casting. A shaft hole 38 into which the motor shaft 72 is inserted is provided at the center of the body portion 30.

  A part of the body portion 30 is formed with a sound deadening chamber 53 that is integral with the sound deadening chamber 53 of the cover body 50. A side surface of the body portion 30 to which the pump portion 80 is attached is referred to as an upper surface 34. A sealing material 41 is fitted along the outer periphery of the upper surface 34 and the outer periphery of the sound deadening chamber 53.

  Further, a semicircular intake groove 42 centering on the shaft hole 38 is provided on the upper surface 34 from the upper side to the lower side of the shaft hole 38, and a sealing material 43 such as an O-ring is provided so as to surround the intake groove 42. It is fitted on the upper surface 34.

  The cover body 50 has a shape in which an inclined portion 55 is provided in a part of a bottomed cylinder, a bottom portion 56 that faces the upper surface 34 of the body portion 30, and a cylindrical portion 57 that extends from the bottom portion 56 toward the upper surface 34. The flange portion 58 is formed at the end portion of the cylindrical portion 57 in a bowl shape.

  FIG. 5 is an exploded perspective view of the pump unit 80. The pump unit 80 includes a non-circular rotor chamber 82 and a case 84 provided with a plurality (four in this example) of bolt holes 83, and a plurality of vane grooves 85. Are provided radially, an involute spline hole 86 is provided at the center, a rotor 87 rotatably accommodated in a rotor chamber 82 having a non-circular cross section, and a vane 88 movably accommodated in a plurality of vane grooves 85, respectively. , An intake plate 94 having a plurality (four in this example) of bolt holes 91 and two upper and lower intake holes 92, 93, a plurality (four in this example) of bolt holes 96 and two upper and lower exhaust outlets 97. , 98 and a plurality of (four in this example) long bolts 81 that pass through the bolt holes 96, 83, 91.

  FIG. 6 is a front view of the negative pressure pump 10. The negative pressure pump 10 is provided on the upper surface 34 of the body portion 30 and generates a negative pressure (FIG. 4, reference numeral 80), and the upper surface 34 of the body portion 30. And a motor 70 that is provided on the lower surface 37 of the body portion 30 and drives the pump portion 80. Although details will be described later, the air sucked from the connection pipe 21 passes through the negative pressure pump 10 and is discharged from an exhaust pipe 111 extending downward from the body portion 30.

The internal structure of the negative pressure pump will be described in more detail based on FIGS.
FIG. 7 is a sectional view of the negative pressure pump 10 assembled based on FIGS. 4 and 5.
As shown in FIG. 7, a rolling bearing 102 is provided in the shaft hole 38, and the motor shaft 72 is supported by the bearing 102. The tip of the motor shaft 72 is fitted into the involute spline hole 86 of the rotor 87, and the tip reaches the vicinity of the lid 101.

The flange portion 58 of the cover body 50 is in contact with the entire circumference of the sealing material 41, and the sealing material 41 ensures airtightness in the cover body 50.
On the other hand, the surface of the intake plate 94 is in contact with the entire periphery of the sealing material 43, and the opening of the intake groove 42 is blocked by the sealing material 43 and the intake plate 94, thereby forming the intake passage 103. As a result, an intake path including the connection pipe 21, the intake port 24, the intake passage 103, and the two intake holes (FIG. 5, reference numerals 92 and 93) is formed.

  On the other hand, the exhaust from the exhaust outlets 97 and 98 of the pump unit 80 is discharged into the storage chamber 51. A space between the storage chamber 51 and the pump unit 80 forms a part of the exhaust path 104. This exhaust path 104 also appears in FIG.

  As shown in FIG. 8, the exhaust path 104 through which the exhaust from the exhaust outlets 97 and 98 passes, the space between the cover body 50 and the pump unit 80 in the storage chamber 51, and the storage chamber 51 and the muffler chamber 53. The communication path 105 to be connected, the muffler chamber 53, a recess 61 provided in the bottom 59 of the muffler chamber 53, and an exhaust pipe 62 connected to the recess 61. The communication path 105 is provided in the body part 30.

Next, one side surface 34 of the body part 30 will be described.
As shown in FIG. 9, a breathing hole 121 for supplying air from the vicinity of the motor shaft 72 to the motor (FIG. 7, reference numeral 70) is provided on one side surface 34 of the body portion 30 at a position away from the exhaust path 104. It is done. The breathing hole 121 is provided for supplying air to the motor 70 to prevent the inside of the motor 70 from being evacuated.

  In addition, a communication path 122 that guides air from the exhaust path 104 to the breathing hole 121 is provided on one side surface 34. The communication path 122 includes a bottom surface portion 123, a barrier 124 that is one step higher than the bottom surface portion 123, and a top surface portion 125 that is one step higher than the barrier 124 and closely contacts the intake plate (see reference numeral 94). Further, the communication path 122 has a meandering shape when viewed from the pump unit (FIG. 7, reference numeral 80) side.

  As shown in FIG. 10, in the communication path 122, the breathing hole 121 is provided on the barrier 124 that is one step higher than the bottom surface portion 123, and is provided at a position where it is difficult for water and foreign matter to enter. In other words, the communication path 122 meanders from the exhaust path 104 to the breathing hole 121, and the breathing hole 121 is positioned one step higher than the bottom surface part 123, thereby preventing intrusion of water and foreign matter. Can do.

Next, the exhaust path 104 will be described based on a cross-sectional view taken along the axis of the communication path 105.
As shown in FIG. 11, the body 30 is provided with a storage chamber side recess 126 that is recessed downward on the upper surface 34 that forms the storage chamber 51. The communication path 105 is provided at the lowest position of the accommodation chamber side recess 126. The communication path 105 connects the storage chamber side recess 126 and the muffler chamber 53 and is inclined downward from the left to the right in the figure. The communication path 105 is formed by drilling the narrow surface 31 of the body portion 30, and the opening is closed with a steel ball 127.

Next, the silencer 53 will be described.
As shown in FIG. 12, a communication path 105 is provided in the muffler chamber 53. The muffler chamber 53 is a space surrounded by the cover body 50 and the bottom 59 of the muffler chamber provided in the body part 30. A recess 61 that is recessed downward is provided at the bottom 59 of the sound deadening chamber, and an exhaust pipe 62 of the recess 61 is connected. The bottom 59 of the silencer is inclined downward from the communicating part of the communication path 105 toward the right in the figure. That is, the concave portion 61 is provided at the lowest position of the silencing of the bottom 59, an exhaust pipe 62 extending from the recess 61 downwardly is provided.

Next, the silencing action of the negative pressure pump 10 will be described.
As shown in FIG. 13, when the motor (FIG. 7, reference numeral 70) operates, the outside air is sucked into the connection pipe 21 by the suction action of the pump unit 80. This intake air is drawn into the suction port 24 (arrow (1)).

  The intake air that has entered the intake port 24 enters the pump unit 80 through the intake hole 92 and is pressurized and discharged from the exhaust outlet 97 (arrow (2)), or is pumped from the intake hole 93 through the intake passage 103. Part 80 is pressurized and discharged from the exhaust outlet 98 (arrow (3)). Exhaust gas discharged from the upper and lower exhaust outlets 97 and 98 flows into the storage chamber 51.

  As shown in FIG. 14, the air compressed by the pump unit 80 is discharged into the storage chamber 51. This exhaust gas is guided to the communication path 105, is discharged to the muffler chamber 53 through the communication path 105, and rapidly expands (arrows (4), (5), (6)). Air suddenly expands and consumes acoustic energy. The silenced exhaust is discharged from the exhaust pipe 62 into the lower atmosphere (arrow (7)).

Next, the drainage action of the negative pressure pump 10 will be described.
As shown in FIG. 15A, water generated by condensation in the negative pressure pump 10 falls on the upper surface 34. The water that has fallen on the upper surface 34 flows from the accommodation chamber side recess 126 through the communication path 105 to the muffler chamber 53 (arrow (8)). As shown in (b), the water that has passed through the communication path 105 flows through the bottom 59 of the muffler chamber (arrow (9)), is collected in the recess 61, and is discharged downward from the exhaust pipe 62 (arrow (10). )).

Next, the action of removing the abrasion powder of the negative pressure pump 10 will be described.
As shown in FIG. 16, a rotating body (vane 88 and rotor 87) is built in the pump unit (FIG. 5, reference numeral 80), and since this rotating body is in sliding contact with the wall, a slight amount of wear powder is generated. . The wear powder is mixed with the exhaust gas and flows into the exhaust path 104 and further flows into the communication path 122. The wear powder is prevented from flowing into the communication path 122 by the barrier 124 and the upper surface portion 125 (arrow (11)). Near the inlet wear particles survived barrier 124 of the contact path 122, since contact path 122 meanders, by way of the barrier 124 and top portion 125, is suppressed from flowing into the rear (arrow (12) (13)). The air from which the wear powder has been removed flows from the breathing hole 121 to the vicinity of the motor shaft 72 (arrow (14)) and is supplied into the motor (FIG. 7, reference numeral 70). A communication path 122 is provided while communicating from the exhaust path 104 to the breathing hole 121 of the motor, and the breathing hole 121 is the highest position in the communication path 122. Since the breathing hole 121 is at the highest position in the communication path 122, it is possible to prevent water from entering the motor 70.

Next, another aspect of FIG. 11 will be described. In addition, about the part which is common in FIG. 11, a code | symbol is diverted and description is abbreviate | omitted.
As shown in FIG. 17, an inner wall 63 is provided inside the cover body 50, and a space between the inner wall 63 and the outer wall 52 of the cover body 50 is formed as a muffler chamber 53. The communication path 131 is formed through the inner wall 63 of the cover body 50. By providing the communication path 131 in the cover body 50, the processing of the body part 30 can be reduced, and the processing cost of the body part 30 can be reduced.

Next, another aspect of FIG. 7 will be described. In addition, about the part which is common in FIG. 7, a code | symbol is diverted and description is abbreviate | omitted.
As shown in FIG. 18, the lid body 101 is provided with exhaust outlets 97 and 98 through which exhaust flows into the storage chamber 51 from the pump unit 80. From these exhaust outlets 97 and 98, pipe-like outlet pipes 132 and 133 are extended into the storage chamber 51. The air compressed by the pump unit 80 is discharged from the outlet pipes 132 and 133 and is rapidly expanded in the storage chamber 51 to consume acoustic energy. As a result, the silencing effect can be improved even in the storage chamber 51.

Next, another aspect of FIG. 12 will be described. In addition, about a site | part common with FIG. 12, a code | symbol is diverted and description is abbreviate | omitted.
As shown in FIG. 19, in the body part 30, an extension pipe part 134 extending to the muffler chamber 53 is provided in the exhaust pipe 62. A plurality of fine holes 135 are provided in the extension pipe portion 134. The exhaust holes can be resonated by the fine holes 135, and the silencing effect can be improved.

According to the negative pressure pump acting as described above, the following effects can be obtained.
As shown in FIG. 9, an exhaust path 104 for exhaust discharged from the pump unit 80 is provided on one side surface 34 of the body unit 30, and air is supplied to the motor 70 shown in FIG. A breathing hole 121 is provided to prevent a vacuum. The breathing hole 121 is provided at a site away from the exhaust path 104.
With this configuration, since the breathing hole 121 is disposed at a site away from the exhaust path 104, the exhaust gas containing wear powder does not immediately reach the breathing hole 121 and suppresses the wear powder from being sucked into the motor 70. be able to. As a result, the durability of the motor 70 can be improved.

As shown in FIG. 9, a communication path 122 that guides air to the breathing hole 121 is provided on one side surface 34 of the body portion 30, and a barrier 124 that blocks the flow of air is provided in the communication path 122.
With this configuration, since the barrier 124 is provided in the communication path 122, the wear powder contained in the exhaust is blocked by the barrier 124, and the exhaust from which the wear powder has been removed can be guided to the breathing hole 121. The air flow is also prevented by the wall portion of the upper surface portion 125 that is one step higher than the barrier 124, and the exhaust gas from which the abrasion powder has been removed can be guided to the breathing hole 121.

As shown in FIG. 9, the communication path 122 was meandered when viewed from the pump unit 80 side shown in FIG.
Since the communication path 122 is meandered, the communication path 122 becomes longer, and wear powder is more efficiently removed.

In the embodiment, the vane pump is described as the negative pressure pump. However, the negative pressure pump is not limited to the vane pump.
Furthermore, the negative pressure pump of the present invention is suitable for a negative pressure pump for a vehicle for making the negative pressure chamber of a negative pressure booster provided in the vehicle negative pressure, but it is not intended to limit the application. However, it can be applied to general machines, general-purpose machines, and general equipment.

  The negative pressure pump of the present invention is suitable for a negative pressure pump for a vehicle for making negative pressure inside a negative pressure chamber of a negative pressure booster provided in the vehicle.

  DESCRIPTION OF SYMBOLS 10 ... Negative pressure pump, 30 ... Body part, 34 ... Upper surface (one side surface), 50 ... Cover body, 70 ... Motor, 72 ... Motor shaft, 80 ... Pump part, 104 ... Exhaust path, 121 ... Breathing hole, 122 ... communication path, 124 ... barrier.

Claims (1)

A pump unit driven by a motor is mounted on one side surface of the body portion as a base, the pump unit is covered with a cover body, and the cover body is mounted on the one side surface,
A negative pressure is provided on the one side surface, which is provided with an exhaust path for exhaust gas exhausted from the pump unit, and is provided with a breathing hole for supplying air to the motor to prevent the motor from being evacuated. In the pump,
The breathing hole is provided between the contact path and a shaft hole communicating with the exhaust passage on one side of the body portion, wherein the communicating path is provided with a plurality of barriers that impede the flow of air, wherein the communicating path the A negative pressure pump characterized by meandering when viewed from the pump side.

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