JP2020105987A - Fluid machine - Google Patents

Abstract

To improve corrosion resistance.SOLUTION: A seal member 50 includes a first split surface protruding part 55 which protrudes from a second lip part 54 side end part on an outer peripheral surface 51b of a seal body part 51 to a groove outer chamfer part 65 to be inserted into the groove outer chamfer part 65 and sandwiched between a rotor housing 14 and a cover member 15. The structure allows reduction of a gap between the groove outer chamfer part 65 and the seal member 50. Thus, salt water is less likely to accumulate in the gap between the groove outer chamfer part 65 and the seal member 50. Therefore, corrosion resistance of a housing 11 and the seal member 50 is improved.SELECTED DRAWING: Figure 3

Description

The present invention relates to a fluid machine.

A fluid machine such as the roots pump disclosed in Patent Document 1, for example, includes a housing having a first housing structure and a second housing structure connected to each other. At least one of the first forming surface of the first housing component and the second forming surface of the second housing component forming the mating surface of the first housing component and the second housing component has an annular seal receiving groove. Are formed. An annular seal member that is an elastic body that seals the inside and outside of the housing is housed in the seal housing groove. The seal accommodating groove has a bottom surface and a pair of side surfaces connected to the bottom surface. Then, in order to make it easier to insert the seal member into the seal accommodating groove, an annular recess may be formed on each of the edges of the pair of side surfaces on the opening side.

JP, 2006-283664, A

By the way, for example, when a vehicle equipped with a fluid machine travels near the coast, salt water is applied from the outside of the housing to the first forming surface of the first housing structure and the second forming surface of the second housing structure. There is a case where an attempt is made to penetrate toward the inside of the housing through the space. In this case, the seal member suppresses intrusion of salt water from the outside of the housing into the inside of the housing via the first forming surface of the first housing structure and the second forming surface of the second housing structure. However, when an annular groove is formed at the opening-side edge of the side surface of the seal accommodating groove that is located on the outer side of the housing, salt water is likely to accumulate in the gap between the groove and the seal member. Then, when the salt concentration of the salt water accumulated in the gap increases, there may occur a problem that the portion of the housing in contact with the salt water and the portion of the seal member in contact with the salt water are corroded by the salt water.

Further, a fuel cell vehicle is equipped with a fuel cell system that supplies oxygen and hydrogen to a fuel cell to generate electric power. For example, a roots pump disclosed in Patent Document 1 is a pump that supplies hydrogen to the fuel cell. Is used as. Hydrogen that has not reacted with oxygen in the fuel cell is sucked into the roots pump. Hydrogen contains the generated water generated by the power generation of the fuel cell. The seal member suppresses leakage of hydrogen containing generated water from the inside of the housing to the outside of the housing via the first forming surface of the first housing structure and the second forming surface of the second housing structure. To do. However, when an annular groove is formed at the opening-side edge of the side surface of the seal housing groove located on the inner side of the housing, hydrogen containing generated water is generated in the gap between the groove and the seal member. It becomes easy to collect. Then, there may occur a problem that a portion of the housing that is in contact with the generated water contained in the hydrogen accumulated in the gap and a portion of the seal member that is in contact with the generated water are corroded by the generated water.

The present invention has been made to solve the above problems, and an object thereof is to provide a fluid machine capable of improving corrosion resistance.

A fluid machine that solves the above-mentioned problems forms a housing having a first housing component and a second housing component that are connected to each other, and forms a mating surface between the first housing component and the second housing component. An annular seal accommodating groove formed on at least one of the first forming surface of the first housing component and the second forming surface of the second housing component, and the inside and outside of the housing that are accommodated in the seal accommodating groove And an annular seal member that is an elastic body, wherein the seal accommodating groove has a bottom surface, a pair of side surfaces connected to the bottom surface, and an annular recess that is provided at the opening-side edges of the pair of side surfaces. And a sealing member that protrudes from the seal body portion, the seal member having an annular seal body portion that is in contact with the first housing constituent body and the second housing constituent body. A protrusion inserted into the groove and sandwiched between the first housing component and the second housing component.

According to this, the protrusion is inserted into the recessed line and is sandwiched between the first housing component and the second housing component, so that the gap between the recessed line and the seal member is reduced, and the recessed line and the seal member are reduced. It becomes difficult for the fluid to collect in the gap between and. Therefore, the corrosion resistance of the housing and the seal member can be improved.

In the above fluid machine, the seal member further includes a plurality of pressing protrusions protruding from the seal body toward one of the pair of side surfaces and arranged at intervals in a circumferential direction of the seal body. The seal body may be pressed between the pair of side surfaces by the plurality of pressing protrusions.

According to this, since the seal main body is pressed between the pair of side surfaces by the plurality of pressing projections, the gap between the side surface of the seal housing groove and the seal member is reduced. Therefore, it becomes difficult for the fluid to collect in the gap between the side surface of the seal housing groove and the seal member. Therefore, the corrosion resistance of the housing and the seal member can be further improved.

In the above fluid machine, it is preferable that a convex portion is formed at the tip of the pressing protrusion.
Since the plurality of pressing projections are arranged at intervals in the circumferential direction of the seal body, when the pressing projections are crushed, the pressing projections on both sides of the seal main body in the circumferential direction are crushed. Elastic deformation is easily allowed. Therefore, even if a protrusion is formed at the tip of the pressing protrusion, when the pressing protrusion elastically deforms on both sides in the circumferential direction of the seal main body, the protrusion is also easily elastically deformed together with the pressing protrusion. Therefore, since the convex portion is formed at the tip of the pressing projection, it is possible to prevent the elastic deformation of the seal member from becoming difficult. It is possible to secure the sealing property of the sealing member while leaving it. Therefore, it is possible to save the trouble of removing the convex portion formed at the tip of the pressing protrusion.

According to this invention, the corrosion resistance can be improved.

FIG. 3 is a plan sectional view showing the roots pump according to the embodiment. 2-2 sectional view taken on the line in FIG. Sectional drawing which expands and shows the periphery of a sealing member. The front view of a seal member. 5 is a sectional view taken along line 5-5 in FIG. 6 is a sectional view taken along line 6-6 in FIG. Sectional drawing which shows the metal mold|die used when molding a sealing member. Sectional drawing which expands and shows the periphery of the sealing member in another embodiment.

An embodiment in which a fluid machine is embodied as a roots pump will be described below with reference to FIGS. The roots pump of this embodiment is mounted on a fuel cell vehicle. Fuel cell vehicles are equipped with a fuel cell system that supplies oxygen and hydrogen to generate electricity. The roots pump is used as a pump that supplies hydrogen (hydrogen off gas) as a fluid to the fuel cell.

As shown in FIG. 1, the housing 11 of the roots pump 10 has a tubular shape having a motor housing 12, a gear housing 13, a rotor housing 14, and a cover member 15. The motor housing 12 has a bottomed cylindrical shape having a plate-shaped bottom wall 12a and a peripheral wall 12b extending in a cylindrical shape from the outer peripheral portion of the bottom wall 12a. The gear housing 13 has a bottomed cylindrical shape having a plate-shaped bottom wall 13a and a peripheral wall 13b extending from the outer peripheral portion of the bottom wall 13a in a cylindrical shape.

The gear housing 13 is connected to the opening side of the peripheral wall 12b of the motor housing 12 in a state where the outer surface 13c of the bottom wall 13a of the gear housing 13 and the opening end surface 12c of the peripheral wall 12b of the motor housing 12 are butted against each other. The bottom wall 13a of the gear housing 13 closes the opening of the peripheral wall 12b of the motor housing 12. The axial center direction of the peripheral wall 12b of the motor housing 12 and the axial center direction of the peripheral wall 13b of the gear housing 13 coincide with each other.

The rotor housing 14 has a bottomed cylindrical shape having a plate-shaped bottom wall 14a and a peripheral wall 14b extending in a cylindrical shape from the outer peripheral portion of the bottom wall 14a. The rotor housing 14 is connected to the opening side of the peripheral wall 13b of the gear housing 13 in a state where the outer surface 14c of the bottom wall 14a of the rotor housing 14 and the opening end surface 13d of the peripheral wall 13b of the gear housing 13 are butted against each other. The bottom wall 14 a of the rotor housing 14 closes the opening of the peripheral wall 13 b of the gear housing 13. The axial center direction of the peripheral wall 13b of the gear housing 13 and the axial center direction of the peripheral wall 14b of the rotor housing 14 coincide with each other.

The cover member 15 has a plate shape. The cover member 15 is connected to the opening side of the peripheral wall 14b of the rotor housing 14 in a state where the one end surface 15a of the cover member 15 and the opening end surface 14d of the peripheral wall 14b of the rotor housing 14 abut each other. The cover member 15 closes the opening of the peripheral wall 14b of the rotor housing 14.

The roots pump 10 has a drive shaft 16 and a driven shaft 17 which are rotatably supported in a state of being arranged in parallel with each other in the housing 11. The rotational axis directions of the drive shaft 16 and the driven shaft 17 coincide with the axial center directions of the peripheral walls 12b, 13b, 14b. A disc-shaped drive gear 18 is fixed to the drive shaft 16. A disk-shaped driven gear 19 that meshes with the drive gear 18 is fixed to the driven shaft 17. A drive rotor 20 is provided on the drive shaft 16. The driven shaft 17 is provided with a driven rotor 21 that meshes with the drive rotor 20.

The roots pump 10 includes an electric motor 22 that rotates the drive shaft 16. The electric motor 22 is housed in a motor chamber 23 formed inside the housing 11. The motor chamber 23 is partitioned by the bottom wall 12a of the motor housing 12, the peripheral wall 12b of the motor housing 12, and the bottom wall 13a of the gear housing 13. The electric motor 22 has a cylindrical motor rotor 22a fixed to the drive shaft 16 so as to be integrally rotatable, and a cylindrical stator 22b fixed to the inner peripheral surface of the peripheral wall 12b of the motor housing 12 and surrounding the motor rotor 22a. have. The stator 22b has a coil 22c wound around a tooth (not shown). The electric motor 22 is driven by supplying electric power to the coil 22c, and the motor rotor 22a rotates integrally with the drive shaft 16.

A gear chamber 24 that accommodates the drive gear 18 and the driven gear 19 is formed in the housing 11. The gear chamber 24 is partitioned by a bottom wall 13 a of the gear housing 13, a peripheral wall 13 b of the gear housing 13, and a bottom wall 14 a of the rotor housing 14. The drive gear 18 and the driven gear 19 are housed in the gear chamber 24 while meshing with each other. The gear chamber 24 is filled with oil. The oil contributes to lubrication of the drive gear 18 and the driven gear 19 and suppression of temperature rise. The drive gear 18 and the driven gear 19 are rotated while being immersed in the oil, so that the drive gear 18 and the driven gear 19 can rotate at a high speed without being seized or worn.

A rotor chamber 25 that accommodates the drive rotor 20 and the driven rotor 21 is formed in the housing 11. The rotor chamber 25 is partitioned by the bottom wall 14 a of the rotor housing 14, the peripheral wall 14 b of the rotor housing 14, and the cover member 15. The drive rotor 20 and the driven rotor 21 are housed in the rotor chamber 25 while meshing with each other. In the present embodiment, the motor chamber 23, the gear chamber 24, and the rotor chamber 25 are arranged side by side in this order in the rotation axis direction of the drive shaft 16.

The bottom wall 13 a of the gear housing 13 separates the gear chamber 24 and the motor chamber 23 in the rotation axis direction of the drive shaft 16. The bottom wall 14 a of the rotor housing 14 separates the gear chamber 24 and the rotor chamber 25 in the rotation axis direction of the drive shaft 16. The cover member 15 separates the rotor chamber 25 from the outside.

The drive shaft 16 penetrates the bottom wall 13 a of the gear housing 13 and the bottom wall 14 a of the rotor housing 14. The driven shaft 17 penetrates the bottom wall 14 a of the rotor housing 14. The inner bottom surface 13e of the bottom wall 13a of the gear housing 13 forms a wall surface on the motor chamber 23 side in the rotation axis direction of the drive shaft 16 and the driven shaft 17 in the gear chamber 24. The outer surface 14c of the bottom wall 14a of the rotor housing 14 forms a wall surface on the rotor chamber 25 side in the rotation axis direction of the drive shaft 16 and the driven shaft 17 in the gear chamber 24.

On the inner bottom surface 13e of the bottom wall 13a of the gear housing 13, a circular hole-shaped first bearing accommodating recess 27 for accommodating the first bearing 26 that rotatably supports the drive shaft 16 is formed. The drive shaft 16 penetrates the first bearing housing recess 27. Further, the bottom surface 27a of the first bearing accommodating recess 27 has a circular hole-shaped first accommodating member 28 in which the drive shaft 16 penetrates and which accommodates an annular first seal member 28 that seals between the gear chamber 24 and the motor chamber 23. The 1-seal accommodation recess 29 is formed. The first seal accommodating recess 29 communicates with the first bearing accommodating recess 27. An annular first spacer 30 is arranged between the first bearing 26 and the bottom surface 27a of the first bearing accommodating recess 27 in the rotation axis direction of the drive shaft 16.

On the outer surface 14c of the bottom wall 14a of the rotor housing 14, there is formed a circular hole-shaped second bearing accommodating recess 32 for accommodating the second bearing 31 that rotatably supports the drive shaft 16. The drive shaft 16 penetrates the second bearing housing recess 32. Further, the bottom surface 32 a of the second bearing accommodating recess 32 has a circular hole-shaped first portion through which the drive shaft 16 penetrates and which accommodates an annular second seal member 33 that seals between the gear chamber 24 and the rotor chamber 25. A two-seal housing recess 34 is formed. The second seal accommodating recess 34 communicates with the second bearing accommodating recess 32. Further, an annular second spacer 35 is arranged between the second bearing 31 and the bottom surface 32 a of the second bearing housing recess 32 in the rotation axis direction of the drive shaft 16.

A circular hole-shaped third bearing accommodating recess 37 for accommodating a third bearing 36 that rotatably supports the driven shaft 17 is formed on the outer surface 14c of the bottom wall 14a of the rotor housing 14. The driven shaft 17 penetrates the third bearing housing recess 37. Further, the bottom surface 37a of the third bearing accommodating recess 37 has a circular hole-shaped first accommodating hole for accommodating the driven shaft 17 and accommodating an annular third seal member 38 that seals between the gear chamber 24 and the rotor chamber 25. A 3-seal housing recess 39 is formed. The third seal accommodating recess 39 communicates with the third bearing accommodating recess 37. An annular third spacer 40 is arranged between the third bearing 36 and the bottom surface 37 a of the third bearing housing recess 37 in the rotation axis direction of the driven shaft 17.

On the inner bottom surface 13e of the bottom wall 13a of the gear housing 13, a circular hole-shaped fourth bearing accommodating recess 42 for accommodating the fourth bearing 41 that rotatably supports one end of the driven shaft 17 is formed. One end of the driven shaft 17 is arranged in the fourth bearing housing recess 42 and is rotatably supported by the fourth bearing 41. The other end of the driven shaft 17 penetrates the third bearing accommodating recess 37 and the third seal accommodating recess 39 and projects into the rotor chamber 25. A driven rotor 21 is attached to the other end of the driven shaft 17, and the other end of the driven shaft 17 is a free end. Therefore, the driven shaft 17 is cantilevered by the housing 11.

A cylindrical bearing portion 44 that accommodates a fifth bearing 43 that rotatably supports one end portion of the drive shaft 16 is formed on the inner bottom surface 12e of the bottom wall 12a of the motor housing 12. One end of the drive shaft 16 is arranged inside the bearing portion 44 and is rotatably supported by the fifth bearing 43. The other end of the drive shaft 16 penetrates the first seal accommodating recess 29, the first bearing accommodating recess 27, the gear chamber 24, the second bearing accommodating recess 32, and the second seal accommodating recess 34 and projects into the rotor chamber 25. ing. The drive rotor 20 is attached to the other end of the drive shaft 16, and the other end of the drive shaft 16 is a free end. Therefore, the drive shaft 16 is cantilevered by the housing 11.

As shown in FIG. 2, the drive rotor 20 and the driven rotor 21 are formed in a bileaflet shape (a gourd shape) in a sectional view orthogonal to the rotation axis direction of the drive shaft 16 and the driven shaft 17. The drive rotor 20 has double-ridged teeth 20a and valley teeth 20b formed between the two teeth 20a. The driven rotor 21 has two crests 21a and troughs 21b formed between the crests 21a.

Then, the drive rotor 20 and the driven rotor 21 are engaged with each other by engaging the crest teeth 20a of the drive rotor 20 with the trough teeth 21b of the driven rotor 21 and the trough teeth 20b of the drive rotor 20 with the crest teeth 21a of the driven rotor 21. The rotor chamber 25 can be rotated while repeating. The drive rotor 20 rotates in the direction of arrow R1 shown in FIG. 2, and the driven rotor 21 rotates in the direction of arrow R2 shown in FIG.

A suction port 45 and a discharge port 46 are formed in the peripheral wall 14b of the rotor housing 14 at positions facing each other with the rotor chamber 25 in between. The suction port 45 and the discharge port 46 connect the rotor chamber 25 and the outside.

A straight line direction Z1 connecting the suction port 45 and the discharge port 46 intersects perpendicularly with the rotation axis lines r1 and r2 of the drive shaft 16 and the driven shaft 17, respectively. The roots pump 10 is mounted on a fuel cell vehicle such that the suction port 45 opens downward in the direction of gravity, and the linear direction Z1 coincides with the direction of gravity. In FIG. 2, the upward direction of the linear direction Z1 is the discharge port 46 side, and the downward direction of the linear direction Z1 is the suction port 45 side.

When the drive shaft 16 is rotated by the drive of the electric motor 22, the driven shaft 17 is rotated in the reverse direction with respect to the drive shaft 16 through the gear coupling of the drive gear 18 and the driven gear 19 meshed with each other. As a result, the drive rotor 20 and the driven rotor 21 are reversely rotated in a state of being meshed with each other, and the roots pump 10 is rotated by the drive rotor 20 and the driven rotor 21 to cause hydrogen to be transferred to the rotor chamber 25 via the suction port 45. Of hydrogen and discharge of hydrogen from the rotor chamber 25 through the discharge port 46.

As shown in FIG. 1, between the opening end surface 12c of the motor housing 12 and the outer surface 13c of the bottom wall 13a of the gear housing 13, and between the opening end surface 13d of the gear housing 13 and the outer surface 14c of the bottom wall 14a of the rotor housing 14. An annular seal member 50 is provided between the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. Each seal member 50 is provided between the opening end surface 12c of the motor housing 12 and the outer surface 13c of the bottom wall 13a of the gear housing 13, and between the opening end surface 13d of the gear housing 13 and the outer surface 14c of the bottom wall 14a of the rotor housing 14. Further, the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are sealed. Therefore, each seal member 50 seals the inside and outside of the housing 11. Each seal member 50 is an elastic body. The seal member 50 is made of rubber.

In FIG. 3, the configuration relating to the seal member 50 provided between the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 will be described in detail. The configuration of the seal member 50 provided between the opening end surface 12c of the motor housing 12 and the outer surface 13c of the bottom wall 13a of the gear housing 13 is as follows: the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. Since the configuration is the same as that of the seal member 50 provided between the two, detailed description thereof will be omitted. Similarly, the configuration of the seal member 50 provided between the opening end surface 13d of the gear housing 13 and the outer surface 14c of the bottom wall 14a of the rotor housing 14 is the same as the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. Since the configuration is the same as that of the seal member 50 provided between and, detailed description thereof will be omitted.

As shown in FIG. 3, the seal member 50 is housed in an annular seal housing groove 60 formed in the open end surface 14d of the rotor housing 14 that is the first housing structure. The opening of the seal accommodating groove 60 is closed by the one end surface 15a of the cover member 15 which is the second housing structure. The opening end surface 14d of the rotor housing 14 is a first forming surface that forms a mating surface with the cover member 15, and the one end surface 15a of the cover member 15 is a second forming surface that forms a mating surface with the rotor housing 14. is there. Further, in the present embodiment, the seal accommodating groove 60 is formed on the first forming surface, and the opening of the seal accommodating groove 60 is closed by the second forming surface. The housing 11 has a first housing structure and a second housing structure that are connected to each other.

The seal accommodating groove 60 has an annular groove inner peripheral surface 61 located on the inner side of the housing 11 and an annular groove outer peripheral surface 62 located on the outer side of the housing 11. Further, the seal accommodating groove 60 has an edge on the groove inner peripheral surface 61 opposite to the opening side of the seal accommodating groove 60 and an edge on the groove outer peripheral surface 62 opposite to the opening side of the seal accommodating groove 60. Has an annular groove bottom surface 63 for connecting to each other. Therefore, the seal accommodating groove 60 has a groove bottom surface 63 which is a bottom surface, and a groove inner peripheral surface 61 and a groove outer peripheral surface 62 which are a pair of side surfaces connected to the groove bottom surface 63. The groove inner peripheral surface 61 and the groove outer peripheral surface 62 extend parallel to each other in the axial direction of the peripheral wall 14b of the rotor housing 14. The groove bottom surface 63 extends in a direction orthogonal to the axial direction of the peripheral wall 14b of the rotor housing 14. The groove bottom surface 63 extends parallel to the open end surface 14d of the rotor housing 14.

The seal accommodating groove 60 has an inner groove chamfered portion 64, which is an annular groove provided in an edge of the groove inner peripheral surface 61 on the opening side of the seal accommodating groove 60. The groove inner chamfer 64 is located at a corner between the opening-side end edge of the seal housing groove 60 on the groove inner peripheral surface 61 and the opening end surface 14d of the rotor housing 14. Further, the seal accommodating groove 60 has a groove outer chamfered portion 65 that is an annular groove provided in an edge of the groove outer peripheral surface 62 on the opening side of the seal accommodating groove 60. The groove outer chamfered portion 65 is located at a corner portion between the edge of the groove outer peripheral surface 62 on the opening side of the seal housing groove 60 and the opening end surface 14 d of the rotor housing 14. The groove inner chamfered portion 64 and the groove outer chamfered portion 65 have a tapered shape (C chamfered shape) that obliquely intersects the opening end surface 14d of the rotor housing 14 in a straight line.

As shown in FIG. 4, the seal member 50 includes an annular seal main body 51 and a plurality of seal main bodies 51 that protrude from the inner peripheral surface 51 a of the seal main body 51 and are arranged at intervals in the circumferential direction of the seal main body 51. And a pressing projection 52. In the following description, the direction that penetrates the seal body 51 is the axial direction of the seal body 51, and the direction that extends to the outer peripheral side around the axis of the seal body 51 is the radial direction of the seal body 51. To do. In the present embodiment, nine pressing protrusions 52 project from the inner peripheral surface 51a of the seal body 51, and the nine pressing protrusions 52 are arranged at equal intervals in the circumferential direction of the seal body 51. There is. Each pressing projection 52 has a thin plate shape that bulges from the inner peripheral surface 51 a of the seal body 51. The thickness direction of each pressing projection 52 coincides with the axial direction of the seal body 51. Both surfaces of the pressing protrusions 52 located on both sides in the thickness direction are flat surfaces extending parallel to each other. The surface of each pressing projection 52 located in the bulging direction from the inner peripheral surface 51a of the seal body 51 is curved and continuous with the inner peripheral surface 51a of the seal body 51.

As shown in FIG. 5, the seal main body 51 has a plurality of annular first lip portions 53. In the present embodiment, the seal body 51 has two first lip portions 53. The two first lip portions 53 extend over the entire circumference of the seal body 51 in the radial direction of the seal body 51 while being separated from each other. The seal body 51 has an annular first recess 53a formed between the adjacent first lip portions 53.

The two first lip portions 53 and the first recessed portions 53a form an end face located on one side in the axial direction of the seal body 51. Of the two first lip portions 53, the first lip portion 53 located on the outer side in the radial direction of the seal body 51 is continuous with the outer peripheral surface 51b of the seal body 51. Of the two first lip portions 53, the first lip portion 53 located radially inside the seal body 51 is continuous with the inner peripheral surface 51 a of the seal body 51. The two first lip portions 53 are adjacent to each other in the radial direction of the seal body 51. The outer surfaces of the two first lip portions 53 overlap each other in the radial direction of the seal body 51. The outer surfaces of the two first lip portions 53 are connected to each other by the inner surface of the first recess 53a. The inner surface of the first recess 53a is curved in an arc shape.

Of the two first lip portions 53, the radial lip width H1 of the seal main body portion 51 of the first lip portion 53 located on the radial outer side of the seal main body portion 51 is constant in the circumferential direction of the seal main body portion 51. It is wide. Of the two first lip portions 53, the radial lip width H2 of the seal main body portion 51 in the first lip portion 53 located inside the seal main body portion 51 in the radial direction is constant in the circumferential direction of the seal main body portion 51. It is wide. The lip widths H1 and H2 of the two first lip portions 53 are the same.

The seal body portion 51 has a plurality of annular second lip portions 54. In the present embodiment, the seal body 51 has two second lip portions 54. The two second lip portions 54 extend over the entire circumference in the circumferential direction of the seal main body 51 while being separated from each other in the radial direction of the seal main body 51. The seal main body 51 has an annular second recess 54a formed between the adjacent second lip portions 54.

The two second lip portions 54 and the second recessed portions 54a form an end face located on the other axial side of the seal body 51. Of the two second lip portions 54, the second lip portion 54 located on the outer side in the radial direction of the seal body 51 is continuous with the outer peripheral surface 51 b of the seal body 51. Of the two second lip portions 54, the second lip portion 54 located inside the seal body 51 in the radial direction is continuous with the inner peripheral surface 51 a of the seal body 51. The two second lip portions 54 are adjacent to each other in the radial direction of the seal body 51. The outer surfaces of the two second lip portions 54 overlap each other in the radial direction of the seal body 51. The outer surfaces of the two second lip portions 54 are connected to each other by the inner surface of the second recess 54a. The inner surface of the second recess 54a is curved in an arc shape.

Of the two second lip parts 54, the radial lip width H3 of the seal body part 51 in the second lip part 54 located radially outside the seal body part 51 is constant in the circumferential direction of the seal body part 51. It is wide. Of the two second lip portions 54, the radial lip width H4 of the seal main body portion 51 of the second lip portion 54 located inside the seal main body portion 51 in the radial direction is constant in the circumferential direction of the seal main body portion 51. It is wide. The lip widths H3 and H4 of the two second lip portions 54 are the same. The lip widths H1 and H2 of the two first lip portions 53 are the same as the lip widths H3 and H4 of the two second lip portions 54, respectively.

The distance L1 between the inner peripheral surface 51a and the outer peripheral surface 51b of the seal body 51 in the radial direction of the seal body 51 is determined by the outer surface of the first lip portion 53 and the second lip portion 54 in the axial direction of the seal body 51. Is smaller than the distance L2 from the outer surface of the. Further, the deepest part 531a of the first recessed part 53a and the deepest part 541a of the second recessed part 54a are arranged at positions overlapping with each other in the axial direction of the seal body 51. Therefore, the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a extends in the axial direction of the seal body 51. In this embodiment, the length L3 of the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a is constant in the circumferential direction of the seal body 51. Therefore, the depths of the first recessed portion 53a and the second recessed portion 54a are constant in the circumferential direction of the seal body 51. The depth of the first recess 53a is the same as the depth of the second recess 54a.

As shown in FIG. 6, in the state before the seal member 50 is accommodated in the seal accommodating groove 60, each pressing protrusion 52 has a center in the axial direction of the seal body 51 on the inner peripheral surface 51 a of the seal body 51. It is located in the department. In the state before the seal member 50 is accommodated in the seal accommodating groove 60, the axial length L4 of the seal main body 51 in the pressing protrusion 52 is determined by the deepest portion 531a of the first recess 53a and the second recess 54a. Is smaller than the length L3 of the straight line S1 connecting the deepest part 541a of Further, in the state before the seal member 50 is housed in the seal housing groove 60, the distance L5 between the outer peripheral surface 51b of the seal body 51 and the tip 52e of the pressing projection 52 in the radial direction of the seal body 51 is: As shown in FIG. 3, the distance L6 is smaller than the distance L6 between the groove inner peripheral surface 61 and the groove outer peripheral surface 62 in the radial direction of the seal accommodating groove 60. Further, the depth L7 of the seal accommodating groove 60 is larger than the length L3 of the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a. Therefore, the depth L7 of the seal accommodating groove 60 is larger than the axial length L4 of the seal main body 51 in the pressing projection 52.

The seal member 50 passes through the tip portion 52e of the pressing protrusion 52 in the axial direction of the seal body 51 in a state before the seal member 50 is housed in the seal housing groove 60 and elastically deformed in the seal housing groove 60. The seal member 50 is designed so that the filling rate in the seal accommodating groove 60 in the cross section of the seal member 50 (cross section shown in FIG. 6) exceeds 100%.

As shown in FIGS. 5 and 6, the seal member 50 has a first split surface protrusion 55 as a protrusion. The first split surface projecting portion 55 projects from the end portion of the outer peripheral surface 51 b of the seal body 51 on the second lip portion 54 side. The first split surface protruding portion 55 is an annular shape that extends over the entire circumference of the seal body 51 in the circumferential direction. The seal member 50 also has a second split surface protrusion 56. The second split surface projecting portion 56 projects from the central portion in the axial direction of the seal body 51 on the inner peripheral surface 51 a of the seal body 51. The second split surface projecting portion 56 is an annular shape that extends over the entire circumference of the seal body 51 in the circumferential direction. Then, a part of the second split surface projecting portion 56 passes through the tip end portion 52e of each pressing projection 52. Therefore, a part of the second split surface protruding portion 56 is formed as a convex portion at the tip of the pressing protrusion 52.

As shown in FIG. 7, the seal member 50 is formed by molding using a mold 70. The mold 70 has a first mold member 71 and a second mold member 72. The first mold member 71 has a bottomed tubular shape, and FIG. 7 shows a part thereof. The first die member 71 is an annular first forming recess 71a and a first outer periphery that is a portion of the opening end surface of the first die member 71 that is located radially outside the first forming recess 71a with respect to the first forming recess 71a. It has a side end surface 71b and a first inner peripheral side end surface 71c which is a portion of the opening end surface of the first mold member 71 which is located radially inward of the first forming recess 71a with respect to the first forming recess 71a. ..

The first forming recess 71a has a first outer peripheral surface 711a, a first inner peripheral surface 712a, and a first bottom surface 713a. The first outer peripheral surface 711a is annular and is continuous with the first outer peripheral end surface 71b. The first inner peripheral surface 712a has an annular shape and is continuous with the first inner peripheral end surface 71c. The first bottom surface 713a is annular and connects the first outer peripheral surface 711a and the first inner peripheral surface 712a.

The first bottom surface 713a is formed with an annular first lip portion forming recess 714a that respectively forms the two first lip portions 53. Further, the first bottom surface 713a is provided with an annular first recessed portion forming protrusion 715a that forms the first recessed portion 53a. The first outer peripheral surface 711a forms a portion of the outer peripheral surface 51b of the seal body 51 from the end portion on the second lip portion 54 side separated from the second lip portion 54 to the portion continuous with the first lip portion 53. To do. The first inner peripheral surface 712a forms a portion on the inner peripheral surface 51a of the seal body 51 closer to the first lip portion 53 than the central portion of the seal body 51 in the axial direction. The first inner peripheral surface 712a is formed with a first protrusion recess 716a that forms a portion on the outer surface of each pressing protrusion 52 closer to the first lip portion 53 than the central portion of the seal body 51 in the axial direction. Has been done. The first protrusion recesses 716a are formed at intervals in the circumferential direction of the first inner peripheral surface 712a.

The second mold member 72 has a bottomed tubular shape, and FIG. 7 shows a part thereof. The second die member 72 is an annular second forming recess 72a, and a second outer periphery that is a portion of the opening end surface of the second die member 72 that is located radially outside the second forming recess 72a with respect to the second forming recess 72a. It has a side end surface 72b and a second inner peripheral side end surface 72c which is a portion of the opening end surface of the second mold member 72 which is located radially inward of the second forming recess 72a with respect to the second forming recess 72a. ..

The second formation recess 72a has a second outer peripheral surface 721a, a second inner peripheral surface 722a, and a second bottom surface 723a. The second outer peripheral surface 721a is annular and is continuous with the second outer peripheral end surface 72b. The second inner peripheral surface 722a is annular and is continuous with the second inner peripheral end surface 72c. The second bottom surface 723a is annular and connects the second outer peripheral surface 721a and the second inner peripheral surface 722a.

The second bottom surface 723a is formed with an annular second lip portion forming recess 724a that respectively forms the two second lip portions 54. Further, the second bottom surface 723a is formed with an annular second concave portion forming convex portion 725a forming the second concave portion 54a. The second outer peripheral surface 721a forms a portion of the outer peripheral surface 51b of the seal body 51 from an end portion on the second lip portion 54 side separated from the second lip portion 54 to a portion continuous with the second lip portion 54. To do. The second inner peripheral surface 722a forms a portion on the inner peripheral surface 51a of the seal body 51 closer to the second lip portion 54 than the central portion of the seal body 51 in the axial direction. The second inner peripheral surface 722a is formed with a second protrusion recess 726a that forms, on the outer surface of each pressing protrusion 52, a portion closer to the second lip portion 54 side than the central portion of the seal body 51 in the axial direction. Has been done. The second protrusion recesses 726a are formed at intervals in the circumferential direction of the second inner peripheral surface 722a.

In the first mold member 71 and the second mold member 72, the first outer peripheral side end face 71b and the second outer peripheral side end face 72b are abutted, and the first inner peripheral side end face 71c and the second inner peripheral side end face 72c are formed. Are assembled to each other in a butted state. Then, the seal member 50 is molded by injecting the rubber material into the space defined by the first forming recess 71a and the second forming recess 72a.

The first split surface protruding portion 55 is formed between the first outer peripheral side end surface 71b and the second outer peripheral side end surface 72b that form the split surface of the mold 70 when the seal member 50 is molded. Is. The second split surface protruding portion 56 is formed between the first inner peripheral side end surface 71c and the second inner peripheral side end surface 72c forming the split surface of the mold 70 when the seal member 50 is molded. It is Bali.

As shown in FIG. 3, the two first lip portions 53 are in contact with the groove bottom surface 63 of the seal housing groove 60. Therefore, the two first lip portions 53 are first seal portions that contact the rotor housing 14 in the direction in which the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are aligned (the direction indicated by the arrow X1 in FIG. 3). Is composed of. In addition, the two second lip portions 54 are in contact with the one end surface 15 a of the cover member 15. Therefore, the two second lip portions 54 form a second seal portion that contacts the cover member 15 in the direction in which the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are aligned with each other. The mating direction of the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 coincides with the axial direction of the peripheral wall 14b of the rotor housing 14. The seal body 51 contacts the rotor housing 14 and the cover member 15.

Furthermore, the plurality of pressing projections 52 project from the inner peripheral surface 51 a of the seal body 51 toward the groove inner peripheral surface 61 of the seal accommodating groove 60. Therefore, the plurality of pressing projections 52 project from the seal body 51 toward one of the pair of side surfaces. The plurality of pressing projections 52 are in contact with the groove inner peripheral surface 61 and press the groove inner peripheral surface 61. At this time, the portion of the second split surface protruding portion 56 formed at the tip of each pressing projection 52 contacts the groove inner peripheral surface 61 and is crushed. The seal main body 51 is in contact with the groove outer peripheral surface 62 in a pressed state by receiving a repulsive force from the groove inner peripheral surface 61 against the pressing force applied to the groove inner peripheral surface 61 by each pressing protrusion 52. Therefore, the seal body 51 is pressed between the groove inner peripheral surface 61 and the groove outer peripheral surface 62 by the plurality of pressing protrusions 52. Further, the first split surface projecting portion 55 projects from the end portion of the outer peripheral surface 51 b of the seal body 51 on the second lip portion 54 side toward the groove outer chamfered portion 65 and is crushed by the groove outer chamfered portion 65. While being inserted, it is sandwiched between the rotor housing 14 and the cover member 15.

Next, the operation of this embodiment will be described.
The seal member 50 passes through the tip portion 52e of the pressing protrusion 52 in the axial direction of the seal body 51 in a state before the seal member 50 is housed in the seal housing groove 60 and elastically deformed in the seal housing groove 60. The sealing member 50 is designed so that the filling rate in the seal receiving groove 60 in the cross section of the sealing member 50 exceeds 100%. Therefore, when the cover member 15 is attached to the rotor housing 14, in the seal member 50, the two first lip portions 53 are in contact with the groove bottom surface 63 of the seal accommodating groove 60 and the two second lip portions 54 are covered. In a state of being in contact with one end surface 15a of the member 15, the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are crushed in the mating direction. Then, the seal member 50 is elastically deformed so as to be crushed in a direction in which the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are crushed, so that the plurality of pressing projections 52 are formed on the groove inner peripheral surface. The inner peripheral surface 61 of the groove is pressed by coming into contact with 61.

When the plurality of pressing projections 52 press the groove inner peripheral surface 61, the pressing projections 52 receive the repulsive force against the pressing force applied to the groove inner peripheral surface 61 by the pressing projections 52 from the groove inner peripheral surface 61. Crushed. When the pressing projections 52 are crushed, the seal main body 51 tends to elastically deform so as to spread on both sides in the circumferential direction of the seal main body 51 with respect to the pressing projections 52. At this time, since the two first lip portions 53 are in contact with the groove bottom surface 63 of the seal housing groove 60 and the two second lip portions 54 are in contact with the one end surface 15a of the cover member 15, the entire seal body portion 51 is As a result, elastic deformation is allowed in the gap between the outer peripheral surface 51b of the seal body 51 and the groove outer peripheral surface 62. As a result, the outer peripheral surface 51b of the seal body 51 comes into contact with the groove outer peripheral surface 62 and the seal body 51 elastically deforms so as to press the groove outer peripheral surface 62. Further, as the outer peripheral surface 51b of the seal body 51 contacts the groove outer peripheral surface 62 in a pressed state, the first split surface projecting portion 55 is inserted into the groove outer chamfered portion 65 while being crushed and inserted, It is sandwiched between the housing 14 and the cover member 15.

By the way, for example, when a fuel cell vehicle travels near the coast, salt water is discharged from the outside of the housing 11 through an opening end surface 14d of the rotor housing 14 and one end surface 15a of the cover member 15 into the housing 11. It may try to invade inside. In this case, the seal member 50 suppresses intrusion of salt water from the outside of the housing 11 into the inside of the housing 11 via the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15.

For example, salt water flowing between the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 is between the outer peripheral surface 51b of the seal body 51 and the groove outer peripheral surface 62, and the two first lip portions. Of the parts 53, it may pass between the first lip part 53 located radially outside the seal body 51 and the groove bottom surface 63. Even in this case, the salt water is diffused inside the first recess 53a, and the straightness of the flow of the salt water is lost. This makes it difficult for salt water to pass through the seal member 50, and makes it difficult for salt water to enter the inside of the housing 11.

For example, salt water flowing between the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 is the second lip portion of the two second lip portions 54, which is located radially outside the seal body 51. It may pass between 54 and the one end surface 15a of the cover member 15. Even in this case, the salt water is diffused inside the second recess 54a, and the straightness of the flow of the salt water is lost. This makes it difficult for salt water to pass through the seal member 50, and makes it difficult for salt water to enter the inside of the housing 11.

The outer peripheral surface 51 b of the seal body 51 receives the repulsive force from the groove inner peripheral surface 61 against the pressing force applied to the groove inner peripheral surface 61 by the plurality of pressing protrusions 52, and is pressed against the groove outer peripheral surface 62. Since they are in contact with each other, the gap between the groove outer peripheral surface 62 and the seal member 50 is small. For this reason, it becomes difficult for salt water to collect in the gap between the groove outer peripheral surface 62 of the seal housing groove 60 and the seal member 50. Furthermore, since the first split surface protrusion 55 is inserted into the groove outer chamfer 65 and is sandwiched between the rotor housing 14 and the cover member 15, the gap between the groove outer chamfer 65 and the seal member 50 is small. Therefore, it becomes difficult for salt water to collect in the gap between the groove outer chamfered portion 65 and the seal member 50.

In the above embodiment, the following effects can be obtained.
(1) The seal member 50 is inserted into the groove outer chamfered portion 65 by protruding toward the groove outer chamfered portion 65 from the end portion of the outer peripheral surface 51b of the seal main body portion 51 on the second lip portion 54 side, It is provided with a first split surface protrusion 55 that is sandwiched between the cover members 15. According to this, the gap between the groove outer chamfered portion 65 and the seal member 50 becomes small. For this reason, it becomes difficult for salt water to collect in the gap between the groove outer chamfered portion 65 and the seal member 50. Therefore, the corrosion resistance of the housing 11 and the seal member 50 can be improved.

(2) The seal member 50 includes a plurality of pressing protrusions 52 that protrude from the seal body 51 toward the groove inner peripheral surface 61 and that are arranged at intervals in the circumferential direction of the seal body 51. The seal body 51 is pressed between the groove inner peripheral surface 61 and the groove outer peripheral surface 62 by the plurality of pressing protrusions 52. According to this, the gap between the groove outer peripheral surface 62 in the seal housing groove 60 and the seal member 50 becomes small. Therefore, it is difficult for salt water to collect in the gap between the groove outer peripheral surface 62 of the seal housing groove 60 and the seal member 50. Therefore, the corrosion resistance of the housing 11 and the seal member 50 can be further improved.

(3) At the tip of the pressing protrusion 52, a part of the second split surface protrusion 56 is formed as a protrusion. Since the plurality of pressing projections 52 are arranged at intervals in the circumferential direction of the seal body 51, when the pressing projections 52 are crushed, the pressing body 52 of each of the pressing projections 52 is pressed. It is easy to allow elastic deformation to both sides in the circumferential direction. Therefore, even if a part of the second split surface protrusion 56 is formed at the tip of the pressing protrusion 52, when the pressing protrusion 52 is elastically deformed to both sides in the circumferential direction of the seal main body 51, A part of the surface protrusion 56 is also easily elastically deformed together with the pressing protrusion 52. Therefore, since the second split surface projecting portion 56 is partially formed at the tip of the pressing projection 52, it is possible to prevent the elastic deformation of the seal member 50 from becoming difficult. The sealing property of the seal member 50 can be ensured while leaving a part of the second split surface protruding portion 56 formed at the tip of 52. Therefore, it is possible to save the trouble of removing a part of the second split surface protruding portion 56 formed at the tip of the pressing protrusion 52.

(4) The first split surface protruding portion 55 is formed between the first outer peripheral side end surface 71b and the second outer peripheral side end surface 72b that form the split surface of the mold 70 when the seal member 50 is molded. It is Bali that is done. In the present embodiment, the first split surface protrusion 55, which is a burr, is inserted into the groove outer chamfered portion 65 and sandwiched by the rotor housing 14 and the cover member 15, so that the groove outer chamfered portion 65 and the seal member 50 are separated from each other. The gap between them is small. Therefore, since the burr formed when molding the seal member 50 is effectively used, it is not necessary to remove the burr which is originally unnecessary, and further, the protruding portion to be inserted into the groove outer chamfered portion 65 has the seal main body. The step of separately forming the portion 51 is unnecessary.

(5) The plurality of pressing projections 52 are arranged at intervals in the circumferential direction of the seal body 51. According to this, for example, as compared with the case where the pressing projections are projected from the inner peripheral surface 51a of the seal body 51 over the entire circumference of the inner peripheral surface 51a of the seal body 51, each pressing projection 52 is When crushed, elastic deformation of each pressing projection 52 to both sides in the circumferential direction of the seal main body 51 is easily allowed. Therefore, the seal main body 51 is suppressed from being elastically deformed so as to push the cover member 15 away, and the sealability between the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 deteriorates. It can be suppressed.

(6) The plurality of annular first lip portions 53 form a first seal portion that contacts the rotor housing 14 in the direction in which the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are aligned with each other. In addition, the plurality of annular second lip portions 54 form a second seal portion that contacts the cover member 15 in the alignment direction of the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. According to this, the salt water flowing between the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 has an annular first recessed portion 53a located between the adjacent first lip portions 53 and the adjacent first recessed portion 53a. It is diffused inside the annular second recess 54 a located between the matching second lip portions 54. As a result, the straightness of the flow of salt water is lost, and it becomes difficult for salt water to pass through the seal member 50. As a result, the sealability of the seal member 50 can be improved.

(7) The distance L1 between the inner peripheral surface 51a and the outer peripheral surface 51b of the seal main body 51 in the radial direction of the seal main body 51 is equal to the outer surface of the first lip portion 53 in the axial direction of the seal main body 51 and the second surface. It is smaller than the distance L2 between the outer surface of the lip portion 54. Even in this case, when the cover member 15 is attached to the rotor housing 14, the plurality of pressing projections 52 come into contact with the groove inner peripheral surface 61 to suppress the collapse (twisting) of the seal member 50. You can

(8) The axial length L4 of the seal body 51 in the pressing protrusion 52 is greater than the length L3 of the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a. Is also small. The depth L7 of the seal accommodating groove 60 is larger than the axial length L4 of the seal main body 51 in the pressing projection 52. According to this, the plurality of pressing projections 52 are suppressed from coming into contact with the groove bottom surface 63 of the seal housing groove 60 or the one end surface 15 a of the cover member 15. Therefore, by receiving a repulsive force against the pressing force applied to the groove inner peripheral surface 61 by the pressing protrusions 52 from the groove inner peripheral surface 61, the outer peripheral surface 51b of the seal body 51 contacts the groove outer peripheral surface 62 and The seal body 51 is easily elastically deformed so as to press the groove outer peripheral surface 62. As a result, the gap between the groove outer peripheral surface 62 of the seal housing groove 60 and the seal member 50 can be reliably reduced.

(9) In the state before the seal member 50 is housed in the seal housing groove 60, the distance L5 between the outer peripheral surface 51b of the seal body 51 and the tip 52e of the pressing projection 52 in the radial direction of the seal body 51 is It is smaller than the distance L6 between the groove inner peripheral surface 61 and the groove outer peripheral surface 62 in the radial direction of the seal accommodating groove 60. According to this, since the seal member 50 can be easily housed in the seal housing groove 60, the assembling property of the seal member 50 to the seal housing groove 60 can be improved.

(10) The depth L7 of the seal accommodating groove 60 is larger than the length L3 of the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a. According to this, when the seal member 50 is elastically deformed so as to be crushed in the direction in which the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are crushed, the first recessed portion 53a and the second recessed portion 53a are formed. It is possible to prevent the portion 54a from disappearing. When the seal body 51 is elastically deformed by receiving a repulsive force against the pressing force applied to the groove inner peripheral surface 61 by each pressing protrusion 52 from the groove inner peripheral surface 61, the first recessed portion 53a and the second recessed portion 53a are formed. It is possible to prevent the portion 54a from disappearing.

The above embodiment can be modified and implemented as follows. The above-described embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

In the embodiment, in the roots pump 10, the seal housing groove 60 is not formed in the opening end surface 14d of the rotor housing 14, but is formed in the one end surface 15a of the cover member 15, and the opening of the seal housing groove 60 is formed in the rotor housing 14. The opening end surface 14d may be closed.

In the embodiment, in the roots pump 10, the seal housing groove 60 is formed not only on the open end surface 14d of the rotor housing 14 but also on the one end surface 15a of the cover member 15. The opening end surface 14d and the one end surface 15a of the cover member 15 may overlap each other in the alignment direction. In short, the seal accommodating groove 60 may be formed on at least one of the first forming surface of the first housing structure and the second forming surface of the second housing structure. In this case, the two second lip portions 54 are in contact with the groove bottom surface 63 of the seal accommodating groove 60 formed in the one end surface 15 a of the cover member 15. Then, the plurality of pressing projections 52 press the portions of the both seal accommodating grooves 60 that straddle the groove inner peripheral surfaces 61, and the outer peripheral surface 51 b of the seal main body 51 has the groove outer peripheral surfaces of the respective seal accommodating grooves 60. It is in contact with 62 while being pressed. According to this, the seal length between the cover member 15 and the seal member 50 and the seal length between the rotor housing 14 and the seal member 50 can be made equal, and the sealability of the seal member 50 is improved. be able to.

As shown in FIG. 8, the groove inner chamfers 64 of both seal housing grooves 60 overlap in the direction in which the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15 are aligned with each other. Further, the groove outer chamfered portions 65 of the respective seal receiving grooves 60 are overlapped with each other in the alignment direction of the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. The annular seal member 50</b>A that does not include the plurality of pressing protrusions 52 may be housed in the seal housing grooves 60. Further, the seal member 50A projects from the inner peripheral surface of the seal member 50A toward the groove inner side chamfered portions 64 of both seal housing grooves 60 and is inserted into the groove inner side chamfered portion 64 as a second split surface protruding portion. It may be configured to have 56A. The second split surface projecting portion 56A is an annular shape that projects from the central portion in the axial direction of the seal member 50A on the inner peripheral surface of the seal member 50A and extends over the entire circumferential direction of the seal member 50A. Further, the seal member 50A has a first split surface protrusion 55A that protrudes from the outer peripheral surface of the seal member 50A toward the groove outside chamfered portions 65 of both seal receiving grooves 60 and is inserted into the groove outside chamfered portion 65. There is. The first split surface projecting portion 55A is an annular shape that projects from the central portion of the outer peripheral surface of the seal member 50A in the axial direction of the seal member 50A and extends over the entire circumferential direction of the seal member 50A.

In the embodiment, the plurality of pressing protrusions 52 may protrude from the outer peripheral surface 51b of the seal body 51. The seal member 50 is accommodated in the seal accommodating groove 60 such that the plurality of pressing protrusions 52 project from the seal body 51 toward the groove outer peripheral surface 62 and press the groove outer peripheral surface 62. May be. In this case, the inner peripheral surface 51 a of the seal main body 51 receives a repulsive force from the groove outer peripheral surface 62 against the pressing force applied to the groove outer peripheral surface 62 by the plurality of pressing protrusions 52, and thus the inner peripheral surface 61 a of the groove inner surface 61. They are in contact with each other while being pressed. Further, the seal member 50 projects from the inner peripheral surface 51 a of the seal body 51 toward the groove inner chamfer 64 of the seal accommodating groove 60, is inserted into the groove inner chamfer 64, and is sandwiched between the rotor housing 14 and the cover member 15. It may have a protruding portion. The protruding portion is an annular shape that protrudes from the end of the inner peripheral surface 51 a of the seal body 51 on the second lip portion 54 side and extends over the entire circumference of the seal body 51 in the circumferential direction.

For example, hydrogen drawn into the rotor chamber 25 contains generated water generated by power generation of the fuel cell. The seal member 50 suppresses leakage of hydrogen containing generated water from the inside of the rotor chamber 25 to the outside of the housing 11 via the opening end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. The inner peripheral surface 51a of the seal body 51 receives a repulsive force from the groove outer peripheral surface 62 against the pressing force applied to the groove outer peripheral surface 62 by the plurality of pressing projections 52, thereby pressing the groove inner peripheral surface 61. Since they are in contact with each other in a closed state, the gap between the groove inner peripheral surface 61 and the seal member 50 is small. Therefore, it becomes difficult for hydrogen containing generated water to accumulate in the gap between the groove outer peripheral surface 62 of the seal housing groove 60 and the seal member 50. Therefore, the corrosion resistance of the housing 11 and the seal member 50 is improved. Furthermore, since the protrusion is inserted into the groove inner chamfer 64 and sandwiched between the rotor housing 14 and the cover member 15, the gap between the groove inner chamfer 64 and the seal member 50 is reduced, and the groove inner chamfer is reduced. It becomes difficult for hydrogen containing generated water to accumulate in the gap between 64 and the seal member 50.

In the embodiment, the seal member 50 may not have the two first lip portions 53 and the first recessed portions 53a. In the seal member 50, the entire end surface located on one side in the axial direction of the seal main body 51 is in contact with the rotor housing 14 in the alignment direction of the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. It may be configured to function as a seal portion. According to this, it is possible to secure a long seal length between the rotor housing 14 and the seal member 50.

In the embodiment, the seal member 50 may not have the two second lip portions 54 and the second recessed portions 54a. Then, in the seal member 50, the entire end surface located on the other side in the axial direction of the seal main body 51 contacts the cover member 15 in the alignment direction of the open end surface 14d of the rotor housing 14 and the one end surface 15a of the cover member 15. It may be configured to function as a seal portion. According to this, it is possible to secure a long seal length between the cover member 15 and the seal member 50.

In the embodiment, the number of the first lip portions 53 may be three or more.
In the embodiment, the number of the second lip portions 54 may be three or more.
In the embodiment, the distance L1 between the inner peripheral surface 51a and the outer peripheral surface 51b of the seal body 51 in the radial direction of the seal body 51 is equal to the outer surface of the first lip portion 53 in the axial direction of the seal body 51. It may be larger than the distance L2 between the outer surface of the second lip portion 54.

In the embodiment, the axial length L4 of the seal main body 51 in the pressing projection 52 is the length of the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a. It may be the same as L3.

In the embodiment, the axial length L4 of the seal main body 51 in the pressing projection 52 is between the outer surface of the first lip portion 53 and the outer surface of the second lip portion 54 in the axial direction of the seal main body 51. If it is smaller than the distance L2, it may be larger than the length L3 of the straight line S1 connecting the deepest part 531a of the first recess 53a and the deepest part 541a of the second recess 54a.

In the embodiment, the number of the pressing protrusions 52 is not particularly limited as long as it is plural, and may be, for example, less than nine or more than nine.
In the embodiment, for example, the rotor housing 14 and the cover member 15 may be connected in a state where the cover member 15 is fitted inside the peripheral wall 14b of the rotor housing 14. In this case, the inner peripheral surface of the peripheral wall 14b of the rotor housing 14 and the outer peripheral surface of the cover member 15 form a mating surface between the rotor housing 14 and the cover member 15, and the inner peripheral surface of the peripheral wall 14b of the rotor housing 14 is formed. The alignment direction of the outer peripheral surface of the cover member 15 and the outer peripheral surface of the cover member 15 is aligned with the radial direction of the peripheral wall 14b of the rotor housing 14.

In the embodiment, the groove inner peripheral surface 61 and the groove outer peripheral surface 62 do not have to extend parallel to each other in the axial center direction of the peripheral wall 14b of the rotor housing 14, and the axial direction of the peripheral wall 14b of the rotor housing 14 is not limited to the axial direction. And may extend obliquely and cross each other.

In the embodiment, the material of the seal member 50 is not limited to rubber as long as it is an elastic body.
In the embodiment, the drive rotor 20 and the driven rotor 21 may have, for example, a three-lobed shape or a four-lobed shape in a sectional view orthogonal to the rotation axis direction of the drive shaft 16 and the driven shaft 17.

In the embodiment, the drive rotor 20 and the driven rotor 21 may have a helical shape, for example.
In the embodiment, the fluid machine is not limited to the roots pump 10, but may be, for example, a scroll compressor or a piston compressor. In short, the type is not particularly limited as long as it is a fluid machine including the housing 11 having the first housing structure and the second housing structure that are connected to each other.

DESCRIPTION OF SYMBOLS 10... Roots pump as a fluid machine, 11... Housing, 14... 1st housing structure rotor housing, 14d... 1st formation surface open end surface, 15... 2nd housing structure cover member, 15a... One end surface that is the second forming surface, 50, 50A... Seal member, 51... Seal main body portion, 52... Pressing projection, 55, 55A... First split surface projecting portion as projecting portion, 56... First projecting portion Split surface projecting portion, 56A... Second split surface projecting portion as a projecting portion, 60... Seal receiving groove, 61... Groove inner peripheral surface that is a side surface, 62... Groove outer peripheral surface that is a side surface, 63... Bottom surface Groove bottom surface, 64... Recessed groove inner chamfer, 65... Recessed groove outer chamfer.

Claims (3)

A housing having a first housing structure and a second housing structure connected to each other;
It is formed on at least one of a first forming surface of the first housing structure and a second forming surface of the second housing structure that form a mating surface of the first housing structure and the second housing structure. An annular seal receiving groove,
An annular seal member that is an elastic body that is housed in the seal housing groove and that seals the inside and outside of the housing,
The seal accommodating groove is a fluid machine having a bottom surface, a pair of side surfaces connected to the bottom surface, and annular recesses respectively recessed at edges of the pair of side surfaces on the opening side. hand,
The seal member is
An annular seal body portion in contact with the first housing structure and the second housing structure;
A fluid machine comprising: a protrusion protruding from the seal main body, inserted into the groove, and sandwiched between the first housing component and the second housing component. The seal member further includes a plurality of pressing protrusions that protrude from the seal body toward one of the pair of side surfaces and that are arranged at intervals in the circumferential direction of the seal body.
The fluid machine according to claim 1, wherein the seal main body portion is pressed between the pair of side surfaces by the plurality of pressing protrusions. The fluid machine according to claim 2, wherein a convex portion is formed at a tip of the pressing projection.