JP2013189911A - Vacuum pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent reduction in durability of a vacuum pump, by restraining damage of a rotor and a side plate, with a simple configuration.SOLUTION: A vacuum pump includes a casing body 22 installed in an electric motor 10, a hollow-shaped cylinder chamber S formed in this casing body 22 and having an opening on both ends of the casing body 22, a rotor 27 on an output shaft 12 of the electric motor 10 and rotatingly driven in the cylinder chamber S together with the output shaft 12, and a pair of side plates 25 and 26 for blocking up the openings of the cylinder chamber S. The output shaft 12 has a hole part 12B arranged in the axial direction in a tip part 12A, and has a tapered pin 70 pressed in the hole part 12B in a state of inserting the output shaft 12 into a shaft hole 27A of the rotor 27 and fixing the rotor 27 to the output shaft 12.

Description

  The present invention relates to a vacuum pump having a rotor attached to a rotating shaft of a driving machine.

  In general, a casing main body attached to a driving machine, a hollow cylinder chamber formed in the casing main body and having openings at both ends of the casing main body, and provided on a rotating shaft of the driving machine to be rotationally driven in the cylinder chamber. There is known a vacuum pump including a rotor and a pair of side plates that close an opening of a cylinder chamber. This type of vacuum pump is used, for example, to generate a vacuum for operating a brake booster of an automobile, and obtains a vacuum by driving a rotor with a drive unit such as an electric motor in a cylinder chamber of a casing. (For example, refer to Patent Document 1).

US Pat. No. 6,491,501

By the way, in a small vacuum pump that operates a brake booster of an automobile, a small and lightweight rotor is used. Therefore, the rotor is not fixed to the rotating shaft, and the axial direction of the rotating shaft is not fixed. It was movably provided. Furthermore, since the rotor is provided at the tip of the rotating shaft, when the rotor is rotated by driving a drive machine, the rotor is likely to move to the tip of the rotating shaft as it rotates and protrude. . For this reason, during operation of the vacuum pump, the rotor comes into contact with the side plate on the front side (the tip side of the rotating shaft), so that the rotor and the side plate are damaged by wear and the durability of the vacuum pump is reduced. Was assumed.
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to prevent damage to the rotor and the side plate with a simple configuration and prevent deterioration of the durability of the vacuum pump.

  In order to achieve the above object, the present invention provides a casing body attached to a driving machine, a hollow cylinder chamber formed in the casing body and having openings at both ends of the casing body, and a rotating shaft of the driving machine. In a vacuum pump comprising a rotor that is provided to be rotated and driven in the cylinder chamber, and a pair of side plates that close the opening of the cylinder chamber, the rotating shaft has a hole portion provided in an axial direction at a tip portion. And a press-fitting member that is press-fitted into the hole and fixes the rotor to the rotary shaft in a state where the rotary shaft is inserted into the shaft hole of the rotor.

  According to this configuration, since the press-fitting member is press-fitted into the hole provided in the rotating shaft, a part of the rotating shaft is deformed to be expanded, and the rotor is fixed by fixing the rotating shaft and the rotor. Movement in the radial direction and thrust direction of the rotating shaft is restricted. For this reason, the contact between the rotor and the side plate is prevented with a simple configuration, whereby wear of the rotor and the side plate is suppressed, and the durability of the vacuum pump can be improved.

  In this configuration, the present invention inserts the rotor into the rotating shaft until it abuts on the side plate located on the drive side, and in this state, the rotating shaft until the press-fitting member exceeds a predetermined reference value. The rotor is fixed to the rotating shaft by being press-fitted into the hole. According to this configuration, the rotor can be easily positioned with respect to the rotating shaft, and the assembly work of the pump can be performed in a short time without being an expert.

  Further, the shaft hole of the rotor may include an insertion portion into which the rotating shaft is inserted, and a small-diameter portion that is positioned closer to the front end of the rotor than the insertion portion and has a smaller diameter than the rotating shaft. . According to this configuration, the shaft hole on the front end side of the rotor is formed to have a diameter smaller than that of the rotating shaft, thereby preventing the rotor from being assembled in the opposite direction with respect to the rotating shaft and improving the assembling efficiency. Can be planned.

  The press-fitting member may be reduced in diameter toward the distal end side in the press-fitting direction. According to this configuration, the press-fitting member can be easily press-fitted into the hole of the rotating shaft, the assembling work can be easily performed, and the movement of the rotor in the thrust direction with respect to the rotating shaft can be reliably restricted. Can do.

  According to the present invention, the rotation shaft includes a hole portion provided in an axial direction at a tip portion, and the rotation shaft is press-fitted into the hole portion in a state where the rotation shaft is inserted into the shaft hole of the rotor. Since the press-fitting member to be fixed to the rotating shaft is provided, the press-fitting member is deformed so that a part of the rotating shaft is expanded by being press-fitted into the hole, and the rotor is fixed by fixing the rotating shaft and the rotor. Movement in the radial direction and thrust direction of the rotating shaft is restricted. For this reason, the contact between the rotor and the side plate is prevented with a simple configuration, whereby wear of the rotor and the side plate is suppressed, and the durability of the vacuum pump can be improved.

It is a schematic diagram of a brake device using the vacuum pump concerning this embodiment. It is side part fragmentary sectional drawing of a vacuum pump. It is the figure which looked at the vacuum pump from the front side. It is a fragmentary sectional side view which shows the connection structure of a rotor and an output shaft. It is a disassembled side view which shows the connection structure of a rotor and an output shaft. It is a fragmentary sectional side view which shows the connection structure of the rotor concerning a modification, and an output shaft.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments according to the invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a brake device 100 using a vacuum pump 1 according to an embodiment of the present invention as a negative pressure source. The brake device 100 includes, for example, front brakes 2a and 2b attached to left and right front wheels of a vehicle such as an automobile, and rear brakes 3a and 3b attached to left and right rear wheels. Each of these brakes is connected to each other by a master cylinder 4 and a brake pipe 9, and each brake is operated by a hydraulic pressure sent from the master cylinder 4 through the brake pipe 9.
The brake device 100 includes a brake booster (brake booster) 6 connected to the brake pedal 5, and the vacuum tank 7 and the vacuum pump 1 are connected in series to the brake booster 6 through an air pipe 8. It is connected. The brake booster 6 uses the negative pressure in the vacuum tank 7 to boost the pedaling force of the brake pedal 5, and it is sufficient to move the piston (not shown) of the master cylinder 4 with a small pedaling force. The brake force can be pulled out.
The vacuum pump 1 is disposed in the engine room of the vehicle, discharges the air in the vacuum tank 7 to the outside of the vehicle, and puts the vacuum tank 7 in a vacuum state. In addition, the use range of the vacuum pump 1 used for a motor vehicle etc. is -60kPa--80kPa, for example.

  FIG. 2 is a side partial sectional view of the vacuum pump 1, and FIG. 3 is a view of the vacuum pump 1 of FIG. 2 as viewed from the front side (right side in the figure). However, FIG. 3 illustrates a state in which members such as the pump cover 24 and the side plate 26 are removed in order to show the configuration of the cylinder chamber S. In the following description, for convenience of explanation, the directions indicated by the arrows at the top of FIGS. 2 and 3 respectively indicate the top, bottom, front, back, left and right of the vacuum pump 1. The front-rear direction is also referred to as the axial direction, and the left-right direction is also referred to as the width direction.

  As shown in FIG. 2, the vacuum pump 1 includes an electric motor (driving machine) 10 and a pump main body 20 that operates using the electric motor 10 as a driving source. The electric motor 10 and the pump main body 20 are integrated with each other. In a connected state, it is fixedly supported on a vehicle body such as an automobile.

The electric motor 10 has an output shaft (rotary shaft) 12 that extends from the approximate center of one end (front end) of the case 11 formed in a substantially cylindrical shape toward the pump body 20 side (front side). The output shaft 12 functions as a drive shaft that drives the pump main body 20, and rotates with reference to a rotation center X1 extending in the front-rear direction. A rotor 27 of the pump body 20 is connected to the tip end portion 12A of the output shaft 12 so as to be integrally rotatable.
In the electric motor 10, when the power source (not shown) is turned on, the output shaft 12 rotates in the direction indicated by the arrow R (counterclockwise) in FIG. 3, thereby rotating the rotor 27 in the same direction around the rotation center X1 ( It is designed to rotate in the direction of arrow R).

The case 11 includes a case main body 60 formed in a bottomed cylindrical shape, and a cover body 61 that closes the opening of the case main body 60. The case main body 60 is formed by bending the peripheral edge portion 60A of the opening outward. ing. The cover body 61 has a disc portion (wall surface) 61A formed to have substantially the same diameter as the opening of the case body 60, and extends in an axial direction from the periphery of the disc portion 61A. And a bent portion 61C formed by bending the outer periphery of the cylindrical portion 61B outward. The disc part 61 </ b> A and the cylindrical part 61 </ b> B enter the case body 60, and the bent part 61 </ b> C is fixed in contact with the peripheral part 60 </ b> A of the case body 60. Thereby, one end part (front end) of the case 11 is recessed inward in the electric motor 10, and the fitting hole part 63 to which the pump main body 20 is attached by spigot fitting is formed.
Further, a through hole 61D through which the output shaft 12 passes and an annular bearing holding portion 61E extending inward of the case main body 60 are formed around the through hole 61D at the approximate center of the disc part 61A. The outer ring of the bearing 62 that supports the output shaft 12 is held on the inner peripheral surface 61F of the bearing holding portion 61E.

  As shown in FIG. 2, the pump main body 20 is integrally cast in the casing main body 22 and the casing main body 22 fitted in the fitting hole 63 formed on the front side of the case 11 of the electric motor 10. The cylinder portion 23 that forms the cylinder chamber S and the pump cover 24 that covers the casing body 22 from the front side are provided. In this embodiment, the casing body 22, the cylinder portion 23, and the pump cover 24 are provided to constitute a casing 31 of the vacuum pump 1.

  As shown in FIG. 3, the casing body 22 is made of, for example, a metal material having high thermal conductivity such as aluminum, and the shape seen from the front side is a substantially rectangular shape that is long in the vertical direction with the rotation center X1 as the center. Is formed. A communication hole 22A communicating with the cylinder chamber S provided in the casing main body 22 is formed in the upper portion of the casing main body 22, and a vacuum suction nipple 30 is press-fitted into the communication hole 22A. As shown in FIG. 2, the vacuum suction nipple 30 is a straight pipe extending upward, and a negative pressure is applied to one end 30A of the vacuum suction nipple 30 from an external device (for example, the vacuum tank 7 (see FIG. 1)). A tube or tube for supplying air is connected.

The casing body 22 is formed with a hole 22B with respect to the axial center X2 extending in the front-rear direction, and a cylindrical cylinder 23 is integrally cast into the hole 22B. Specifically, in a state where the cylinder part (cylinder liner) 23 is set in a mold, a casing body 22 (casing 31) in which the cylinder part 23 is integrally cast is cast by pouring water into the mold. The In the present embodiment, the cylinder portion 23 is integrally cast into the casing main body 22. However, the present invention is not limited to this, and the cylinder portion 23 is press-fitted into the hole 22 </ b> B of the cylinder main body 22 that has been cast in advance. It is also good.
The shaft center X2 is parallel to the rotation center X1 of the output shaft 12 of the electric motor 10 described above and, as shown in FIG. In this configuration, the shaft center X2 is eccentric so that the outer peripheral surface 27B of the rotor 27 centered on the rotation center X1 is in contact with the inner peripheral surface 23A of the cylinder portion 23 formed with reference to the shaft center X2.

The cylinder part 23 is made of the same metal material as the rotor 27 (in this embodiment, iron). In this configuration, the cylinder portion 23 and the rotor 27 have the same thermal expansion coefficient. Therefore, regardless of the temperature changes of the cylinder portion 23 and the rotor 27, the outer peripheral surface 27B of the rotor 27 and the cylinder portion 23 when the rotor 27 rotates. The contact with the inner peripheral surface 23A can be prevented. The cylinder part 23 and the rotor 27 may be made of different materials as long as they are metal materials having substantially the same thermal expansion coefficient.
Moreover, since the cylinder part 23 can be accommodated within the longitudinal range of the casing body 22 by casting the cylinder part 23 integrally in the hole 22B formed in the casing body 22, the cylinder part 23 is prevented from protruding from the casing main body 22, and the casing main body 22 can be downsized.
Further, the casing body 22 is formed of a material having higher thermal conductivity than the rotor 27. According to this, heat generated when the rotor 27 and the vane 28 are rotationally driven can be quickly transmitted to the casing body 22, so that the casing body 22 can sufficiently dissipate heat.

  An opening 23B that connects the communication hole 22A of the casing body 22 and the inside of the cylinder chamber S is formed in the cylinder portion 23, and the air that has passed through the vacuum suction nipple 30 passes through the communication hole 22A and the opening 23B. Supplied in. For this reason, in this embodiment, the suction path 32 is formed by including the vacuum suction nipple 30, the communication hole 22 </ b> A of the casing body 22, and the opening 23 </ b> B of the cylinder portion 23. Discharge ports 22 </ b> C and 23 </ b> C that pass through the casing body 22 and the cylinder part 23 and discharge air compressed in the cylinder chamber S are provided below the casing body 22 and the cylinder part 23.

  Side plates 25 and 26 that close the opening of the cylinder chamber S are disposed at the rear end and the front end of the cylinder portion 23, respectively. The side plates 25 and 26 are set to have a diameter larger than the inner diameter of the inner peripheral surface 23A of the cylinder portion 23, and are urged by the seal rings 25A and 26A, respectively, to the front end and the rear end of the cylinder portion 23, respectively. It is pressed. Thus, a sealed cylinder chamber S is formed inside the cylinder portion 23 except for the opening 23B and the discharge ports 23C and 22C connected to the vacuum suction nipple 30.

  A rotor 27 is disposed in the cylinder chamber S. The rotor 27 has a columnar shape extending along the rotation center X1 of the electric motor 10, and has a shaft hole 27A through which the output shaft 12 that is a drive shaft of the pump body 20 is inserted, and radial direction from the shaft hole 27A. A plurality of guide grooves 27C are provided at equidistant intervals around the shaft hole 27A at intervals in the circumferential direction.

The length of the rotor 27 in the front-rear direction is set to be approximately equal to the length of the cylinder chamber S of the cylinder portion 23, that is, the distance between the mutually facing inner surfaces of the two side plates 25, 26. And the side plates 25 and 26 are substantially closed.
Further, as shown in FIG. 3, the outer diameter of the rotor 27 is such that the outer peripheral surface 27B of the rotor 27 maintains a minute clearance with the portion of the inner peripheral surface 23A of the cylinder portion 23 that is located obliquely downward to the right. Is set. Thereby, as shown in FIG. 3, a crescent-shaped space is formed between the outer peripheral surface 27 </ b> B of the rotor 27 and the inner peripheral surface 23 </ b> A of the cylinder portion 23.

  The rotor 27 is provided with a plurality (five in this example) of vanes 28 that divide a crescent-shaped space. The vane 28 is formed in a plate shape, and its length in the front-rear direction is set to be approximately equal to the distance between the mutually facing inner surfaces of the two side plates 25, 26, similar to the rotor 27. ing. These vanes 28 are arranged so as to be able to protrude and retract from guide grooves 27 </ b> C provided in the rotor 27. As the rotor 27 rotates, each vane 28 protrudes outward along the guide groove 27 </ b> C by centrifugal force, and the tip of the vane 28 comes into contact with the inner peripheral surface 23 </ b> A of the cylinder portion 23. As a result, the crescent-shaped space described above is divided into five compression chambers P surrounded by the two vanes 28 and 28 adjacent to each other, the outer peripheral surface 27B of the rotor 27, and the inner peripheral surface 23A of the cylinder portion 23. Partitioned. These compression chambers P rotate in the same direction as the rotor 27 rotates in the direction of arrow R accompanying the rotation of the output shaft 12, and the volume of the compression chamber P increases near the opening 23B, and decreases at the discharge port 23C. That is, the air sucked into one compression chamber P from the opening 23B by the rotation of the rotor 27 and the vane 28 is compressed while being rotated with the rotation of the rotor 27, and is discharged from the discharge port 23C.

In this configuration, as shown in FIG. 2, the cylinder portion 23 is formed in the casing body 22 such that the axial center X2 of the cylinder portion 23 is eccentrically inclined leftward and upward with respect to the rotation center X1. For this reason, a large space can be secured in the casing main body 22 in the direction opposite to the eccentricity of the cylinder portion 23, and the discharge ports 23 </ b> C and 22 </ b> C are provided in this space along the peripheral edge of the cylinder portion 23. An expansion chamber 33 communicated with is formed.
The expansion chamber 33 is formed as a large closed space along the peripheral edge of the cylinder portion 23 from below the cylinder portion 23 to above the output shaft 12, and communicates with an exhaust port 24 </ b> A formed in the pump cover 24. ing. The compressed air that has flowed into the expansion chamber 33 expands and disperses in the expansion chamber 33, collides with the partition walls of the expansion chamber 33, and is irregularly reflected. Thereby, since the sound energy of compressed air is attenuated, noise and vibration during exhaust can be reduced. In the present embodiment, the exhaust passage 37 is configured by including discharge ports 22 </ b> C and 23 </ b> C, an expansion chamber 33, and an exhaust port 24 </ b> A formed in the casing body 22 and the cylinder part 23, respectively.

  In the present embodiment, by disposing the cylinder portion 23 eccentrically from the rotation center X1 of the rotor 27, a large space can be secured in the peripheral portion on the rotation center X1 side of the cylinder portion 23 in the casing body 22. For this reason, since the expansion chamber 33 can be formed integrally with the casing body 22 by forming the large expansion chamber 33 in this space, there is no need to provide the expansion chamber 33 outside the casing body 22. The main body 22 can be downsized, and the vacuum pump 1 can be downsized.

  The pump cover 24 is disposed on the front side plate 26 via a seal ring 26 </ b> A, and is fixed to the casing body 22 with bolts 66. As shown in FIG. 2, a seal groove 22D is formed on the front surface of the casing body 22 so as to surround the cylinder portion 23 and the expansion chamber 33, and an annular seal material 67 is disposed in the seal groove 22D. The pump cover 24 is provided with an exhaust port 24 </ b> A at a position corresponding to the expansion chamber 33. This exhaust port 24A is for exhausting the air that has flowed into the expansion chamber 33 to the outside of the machine (outside the vacuum pump 1), and this exhaust port 24A prevents the backflow of air from the outside of the machine into the pump. A check valve 29 is attached.

As described above, the vacuum pump 1 is configured by connecting the electric motor 10 and the pump main body 20, and the rotor 27 and the vane 28 connected to the output shaft 12 of the electric motor 10 are the cylinder portion of the pump main body 20. 23 slides in. For this reason, it is important to assemble the pump body 20 in accordance with the rotation center X1 of the output shaft 12 of the electric motor 10.
For this reason, in this embodiment, the electric motor 10 has a fitting hole 63 formed around the rotation center X1 of the output shaft 12 on one end side of the case 11. On the other hand, as shown in FIG. 2, a cylindrical fitting portion 22 </ b> F projecting rearward around the cylinder chamber S is integrally formed on the back surface of the casing body 22. The fitting portion 22 </ b> F is formed concentrically with the rotation center X <b> 1 of the output shaft 12 of the electric motor 10, and has an outer diameter that fits in the fitting hole portion 63 of the electric motor 10.
For this reason, in this configuration, the center position can be easily adjusted by simply fitting the fitting portion 22F of the casing body 22 into the fitting hole portion 63 of the electric motor 10, and the electric motor 10 and the pump body 20 can be aligned. Assembly work can be performed easily. Further, a seal groove 22E is formed around the fitting portion 22F on the back surface of the casing body 22, and an annular seal material 35 is disposed in the seal groove 22E.

  By the way, in a small vacuum pump used for a brake device of an automobile, a small and light rotor is generally used. Further, in order to improve the efficiency of the assembly work of the pump, the rotor is connected to the output shaft. It is not fixed and is provided so as to be movable in the axial direction of the output shaft. In addition, since the rotor is so-called cantilevered at the tip of the output shaft of the electric motor, when the rotor is rotated, the rotor tends to protrude toward the tip of the output shaft as it rotates. It was. For this reason, in the conventional configuration, it is assumed that the rotor and the side plate are damaged by wear due to the contact of the rotor with the front side plate during operation of the vacuum pump, and the durability of the vacuum pump is lowered. Is done.

To solve this problem, the rotor and output shaft are connected by a spline, the rotor is fixed in the radial direction, a push nut is attached to the tip of the output shaft, and the rotor moves in the axial (thrust) direction. The structure which regulates to do is considered.
In this configuration, there is an advantage that the push nut can easily prevent the rotor from protruding toward the tip end side of the output shaft with rotation.
However, since the rigidity of the push nut itself is low, the push nut elastically changes due to the stress of the rotor, so that the rotor moves in the axial direction by the elastic change. According to this, it was assumed that the performance of the vacuum pump may vary due to the rotor moving slightly in the cylinder chamber. For this reason, this structure has a feature in the connection structure between the rotor 27 and the output shaft 12.

4 is a partial side sectional view showing a connection structure between the rotor 27 and the output shaft 12, and FIG. 5 is an exploded side view showing the connection structure of FIG.
The output shaft 12 includes a hole 12B that is drilled in the axial direction at the tip 12A. In a state where the output shaft 12 is inserted into the shaft hole 27A penetrating the rotor 27 in the axial direction, a taper pin (member) 70 is press-fitted into the hole portion 12B. As a result, the diameter of the distal end portion 12A of the output shaft 12 is increased, and the output shaft 12 and the rotor 27 are connected so as to be integrally rotatable.
Here, in the present embodiment, the taper pin 70 is formed of a highly rigid metal material such as iron, and includes a tapered surface 70A that gradually decreases in diameter toward the distal end side in the press-fitting direction, as shown in FIG. It has a different shape. For this reason, when the taper pin 70 is press-fitted into the hole 12 </ b> B, the output shaft 12 is in a state where the diameter of the distal end surface 12 </ b> C is further expanded, and thus the rotor 27 can be restricted from moving toward the distal end side of the output shaft 12. it can.

On the other hand, the shaft hole 27A of the rotor 27 includes a shaft holding portion (insertion portion) 27D into which the tip portion 12A of the output shaft 12 is fitted, and a small diameter portion 27E having a diameter smaller than that of the shaft holding portion 27D. 27F is formed between the shaft holding portion 27D and the shaft holding portion 27D.
The shaft holding portion 27D is formed to have substantially the same diameter as the tip portion 12A of the output shaft 12, and is formed to be longer than half of the total length of the rotor 27 of the rotor. Thereby, since the rotor 27 is fitted with the front-end | tip part 12A of the output shaft 12 over half or more of the full length, the inclination of this rotor 27 is prevented.

  Further, the length of the shaft holding portion 27D is formed to be larger than the length of the front end portion 12A of the output shaft 12 (specifically, the length from the side plate 25 on the electric motor side to the front end surface 12C). As shown in FIG. 4, a slight gap t is formed between the front end surface 12C of the output shaft 12 and the stepped portion 27F of the shaft hole 27A of the rotor 27. According to this, when the rotor 27 is inserted into the output shaft 12, the front end surface 12C of the output shaft 12 is prevented from coming into contact with the step portion 27F before the rotor 27 comes into contact with the side plate 25. It can be done efficiently.

Further, as shown in FIG. 4, the inner diameter D of the small diameter portion 27E is smaller than the outer diameter of the output shaft 12 and larger than the inner diameter of the hole portion 12B. According to this configuration, even if the rotor 27 is to be inserted into the output shaft 12 from the opposite side (that is, the small diameter portion 27E side), the small diameter portion 27E is formed smaller than the outer diameter of the output shaft 12. As a result, it is possible to prevent assembling in the opposite direction and to improve the assembling efficiency. In particular, in the configuration in which the taper pin 70 is press-fitted into the hole 12B of the output shaft 12 and the rotor 27 is fixed as in the present configuration, the taper pin 70 may be disassembled if it is press-fitted in a state where the front and rear are assembled incorrectly. Preventing assembly is very important because it becomes difficult.
Further, in the present embodiment, the taper pin 70 is set to such a length that the taper pin 70 does not protrude from the front end surface 27G of the rotor 27 when the taper pin 70 is press-fitted into the hole 12B.

Next, the procedure for assembling the rotor 27 will be described.
First, the output shaft 12 is inserted into the shaft hole 27 </ b> A of the rotor 27. In this case, since the length of the rotor 27 is set to be substantially the same as the length of the cylinder chamber S (FIG. 2), the rotor 27 is inserted until the rear end surface 27I of the rotor 27 abuts on the rear side plate 25. Thus, the front end surface 27G of the rotor 27 and the opening of the cylinder chamber S are substantially flush with each other.
Subsequently, the taper pin 70 is press-fitted into the hole 12 </ b> B of the output shaft 12. When the rotor 27 is inserted into the output shaft 12 until the rotor 27 comes into contact with the side plate 25, the tip surface 12C of the output shaft 12 is positioned near the small diameter portion 27E of the rotor 27 as shown in FIG.
In this state, the reduced diameter tip portion of the taper pin 70 is fitted into the hole 12B through the small diameter portion 27E, and the taper pin 70 is press-fitted using a dedicated jig (not shown) capable of measuring the press-fitting load. Press-fit until the load exceeds a predetermined threshold (for example, 100 N). As a result, the diameter of the output shaft 12 is increased, whereby the rotor 27 is positioned by being sandwiched between the rear side plate 25 and the taper pin 70.
In the present embodiment, the rotor 27 can be easily positioned with respect to the output shaft 12 by a simple operation of inserting the rotor 27 into the output shaft 12 until it abuts against the side plate 25. Further, the taper pin 70 is attached to a predetermined pin. By press-fitting into the hole 12B until it exceeds the reference value, it can be easily determined that the assembly of the rotor 27 has been completed depending on whether or not this reference value has been exceeded. Can be performed in a short time.

As described above, according to the present embodiment, the casing body 22 attached to the electric motor 10 and the hollow cylinder chamber S formed in the casing body 22 and having openings at both ends of the casing body 22 are provided. The output shaft 12 of the electric motor 10 includes a rotor 27 that is rotationally driven in the cylinder chamber S together with the output shaft 12, and a pair of side plates 25 and 26 that close the opening of the cylinder chamber S. The tip portion 12A is provided with a hole portion 12B provided in the axial direction, and the output shaft 12 is inserted into the shaft hole 27A of the rotor 27 and is press-fitted into the hole portion 12B to fix the rotor 27 to the output shaft 12. Since the taper pin 70 is provided, the taper pin 70 is deformed so that a part of the output shaft 12 is expanded by being press-fitted into the hole 12B. And by fixing the 27, it is restricted that the rotor 27 is moved in the radial direction and the thrust direction of the output shaft 12. For this reason, contact between the rotor 27 and the side plates 25 and 26 is prevented with a simple configuration, so that wear of the rotor 27 and the side plates 25 and 26 is suppressed, and durability of the vacuum pump 1 is improved. Can do.
Furthermore, in this embodiment, since the rotor 27 is prevented from moving in the axial direction in the cylinder chamber S, variations in the performance of the vacuum pump 1 based on this movement can be suppressed.

  Further, according to the present embodiment, the rotor 27 is inserted into the output shaft 12 until it abuts on the rear side plate 25 located on the electric motor side, and in this state, the taper pin 70 is output until it exceeds a predetermined reference value. Since the rotor 27 is fixed to the output shaft 12 by being press-fitted into the hole 12B of the shaft 12, the rotor 27 with respect to the output shaft 12 can be simply operated by inserting the rotor 27 into the output shaft 12 until it contacts the side plate 25. Can be easily positioned. Further, by press-fitting the taper pin 70 into the hole 12B of the output shaft 12 until it exceeds a predetermined reference value, it is possible to easily determine that the positioning of the rotor 27 is completed depending on whether or not this reference value is exceeded. Even if it is not an expert, the assembly | attachment operation | work of a pump can be performed in a short time.

  Further, according to the present embodiment, the shaft hole 27A of the rotor 27 is positioned on the side of the front end surface 27G of the rotor 27 from the shaft holding portion 27D in which the output shaft 12 is fitted and held, and the shaft holding portion 27D. Since the shaft hole 27A on the front end side of the rotor 27 is formed to have a diameter smaller than that of the output shaft 12, the rotor 27 is connected to the output shaft 12. On the other hand, assembling in the opposite direction is prevented, and assembling efficiency can be improved.

  Further, since the taper pin 70 has a shape gradually reduced in diameter toward the distal end side in the press-fitting direction, the taper pin 70 can be easily press-fitted into the hole portion 12B of the output shaft 12, and the assembling work is facilitated. In addition, the movement of the rotor 27 relative to the output shaft 12 in the thrust direction can be reliably restricted.

  Although the best embodiment for carrying out the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications and changes can be made based on the technical idea of the present invention. It is. For example, in the above-described embodiment, the configuration in which the taper pin 70 is employed as the press-fitting member has been described. However, the present invention is not limited to this, and a ball formed of a metal material having high rigidity such as iron as shown in FIG. A configuration may be adopted in which the shaped member (press-fit member) 80 is press-fitted into the hole 12B of the output shaft 12. Since other configurations are the same as the above-described configurations, the same reference numerals are given and description thereof is omitted.

  The ball-shaped member 80 is a member formed in a spherical shape, and it is necessary to finely manage the diameter of the molded ball-shaped member 80 as compared with the taper pin 70. Since there is no need to check each time, there is an advantage that the assembling work can be easily performed.

1 Vacuum pump 6 Brake booster (brake booster)
7 Vacuum tank 9 Brake piping 10 Electric motor (driving machine)
11 Case 12 Output shaft (Rotating shaft)
12A tip portion 12B hole portion 12C tip surface 20 pump body 22 casing body 23 cylinder portion 25 side plate 26 side plate 27 rotor 27A shaft hole 27D shaft holding portion (insertion portion)
27E Small-diameter portion 27G Front end surface 27I Rear end surface 28 Vane 70 Taper pin (press-fit member)
80 Ball-shaped member (press-fit member)
100 Brake device

Claims (4)

A casing main body attached to the drive machine, a hollow cylinder chamber formed in the casing main body and having openings at both ends of the casing main body, and provided on a rotation shaft of the drive machine to be rotationally driven in the cylinder chamber. In a vacuum pump comprising a rotor and a pair of side plates that close the opening of the cylinder chamber,
The rotating shaft includes a hole portion provided in an axial direction at a distal end portion, and the rotor shaft is press-fitted into the hole portion to fix the rotor to the rotating shaft in a state where the rotating shaft is inserted into the shaft hole of the rotor. A vacuum pump comprising a press-fitting member.   The rotor is inserted into the rotary shaft until it abuts on the side plate located on the drive machine side, and in this state, the press-fitting member is press-fitted into the hole of the rotary shaft until a predetermined reference value is exceeded. The vacuum pump according to claim 1, wherein the rotor is fixed to the rotating shaft.   The shaft hole of the rotor includes an insertion portion into which the rotating shaft is inserted, and a small-diameter portion that is positioned closer to the front end side of the rotor than the insertion portion and has a smaller diameter than the rotating shaft. The vacuum pump according to claim 1 or 2.   The vacuum pump according to any one of claims 1 to 3, wherein the press-fitting member has a diameter reduced toward a distal end side in a press-fitting direction.

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