JP7421432B2 - control valve - Google Patents

Description

The present invention relates to control valves.

As a conventional control valve, for example, one described in Patent Document 1 below is known. In this control valve, a cylindrical valve body is rotatably housed in a valve housing hole provided inside a housing. A shaft through hole into which the drive shaft of the electric motor is inserted is formed in the center of the upper wall of the housing along the direction of the rotation axis of the drive shaft. The housing is made of, for example, a synthetic resin material in order to reduce weight. Moreover, the space between the drive shaft and the shaft through hole is liquid-tightly sealed by an annular seal member.

The sealing member includes a metal cylindrical portion and a resin seal that is held inside the cylindrical portion and slides on the inner periphery of the drive shaft. The sealing member is fixed in the shaft through-hole by press-fitting the cylindrical portion into the shaft through-hole of the synthetic resin housing from the axial direction.

Japanese Patent Application Publication No. 2019-163771

However, in the conventional control valve described in Patent Document 1, since the radial cross-sectional shape of the shaft through hole is formed into a substantially perfect circular shape, the metal cylindrical portion described above is press-fitted therein. Then, this press-fitting load is applied to the entire inner circumferential surface of the shaft through hole, causing cracks to occur in a portion of the inner circumferential surface of the shaft through hole, and depending on the case, there is a fear that the housing may be damaged.

The present invention has been devised in view of the technical problems of the prior art, and provides a control valve that can suppress the occurrence of cracks and damage to the housing when a cylindrical part is press-fitted into the shaft through hole of the housing. is intended to provide.

As one aspect of the present invention, there is provided a synthetic resin housing having a shaft through hole into which a drive shaft is inserted; a drive section having the drive shaft that is inserted and capable of rotating the valve body; and a sealing member disposed between the inner circumferential surface of the shaft through hole and the outer circumferential surface of the drive shaft. The through hole has a non-circular portion whose cross section in a direction perpendicular to the central axis of the shaft through hole is non-circular,
The seal member includes a cylindrical part made of a ferrous metal material from the housing that is press-fitted into the non-circular part of the shaft through hole, and a seal that is provided on the inner periphery of the cylindrical part and slides on the drive shaft. and a sealant disposed between the inner periphery of the shaft through hole and the outer periphery of the cylindrical portion.

According to the aspect of the present invention, it is possible to suppress the occurrence of cracks in the housing when the cylindrical part is press-fitted into the shaft through-hole.

FIG. 1 is a block diagram showing the configuration of an automobile cooling water circulation circuit to which a control valve according to the present invention is applied. It is a top view of the control valve of this embodiment. 3 is a sectional view taken along line AA in FIG. 2. FIG. FIG. 2 is an enlarged cross-sectional view of main parts of the present embodiment. FIG. 3 is an enlarged cross-sectional view of the main part of the first housing with the seal member removed. 6 is a view taken along arrow B in FIG. 5. FIG. FIG. 7 is a partially cutaway front view of the first housing showing a state in which the seal member is press-fitted into the shaft through hole. FIG. 3 is a partially cutaway perspective view of the first housing showing a state in which the seal member is press-fitted into the shaft through hole. FIG. 2 is an enlarged sectional view of a main part showing a second embodiment of the present invention.

Hereinafter, embodiments of a control valve according to the present invention will be described based on the drawings. In this embodiment, a control valve will be explained using an example in which the control valve is applied to a circulation system for automobile cooling water (hereinafter simply referred to as "cooling water") similar to the conventional one.

(Configuration of cooling water circulation circuit)
FIG. 1 shows a block diagram showing the configuration of a cooling water circulation circuit to which a control valve CV according to the present invention is applied.

Control valve CV is arranged on the side of engine EG (specifically, a cylinder head not shown). As shown in FIG. 1, this control valve CV is arranged between the heater HT, oil cooler OC, and radiator RD. The heater HT is a heating heat exchanger that performs heat exchange to generate warm air for an air conditioner (not shown). The oil cooler OC cools oil for lubricating the sliding parts inside the engine EG. Radiator RD cools cooling water used to cool engine EG.

Here, the symbol WP in the figure is a water pump that circulates cooling water. Further, reference numeral WT is a water temperature sensor used to control the drive of the control valve CV, and the control valve CV is drive-controlled in accordance with the detection result of the water temperature sensor WT. Moreover, the symbol TC is a throttle chamber that controls the flow rate of air mixed with the fuel combusted within the engine EG, and the symbol EC is an EGR cooler that cools the exhaust gas after combustion of the engine EG.

Specifically, cooling water discharged from water pump WP is guided to control valve CV through introduction passage L0. Then, the rotor RT in the control valve CV is driven and controlled based on the operating state of the engine EG, such as the detection result by the water temperature sensor WT. As a result, the cooling water led to the control valve CV via the introduction passage L0 is distributed to the heater HT, oil cooler OC, and radiator RD via the first to third pipes L1 to L3, respectively.

Further, the control valve CV is provided with a bypass passage BL for directly guiding the cooling water from the engine EG to the throttle chamber TC by bypassing the introduction passage L0. Thereby, the cooling water guided to the control valve CV via the bypass passage BL is constantly supplied to the throttle chamber TC. Note that, like the heater HT, the cooling water supplied to the throttle chamber TC is guided to the EGR cooler EC, and is returned to the engine EG side via the EGR cooler EC and the water pump WP.

In this way, the control valve CV is applied as a so-called 1in-3out type distribution device, and distributes the cooling water flowing in from the introduction passage L0 to the first to third pipes L1 to L3, and also controls the cooling water at the time of distribution. Control the flow of water.

(Configuration of control valve)
FIG. 2 is a plan view of the control valve of this embodiment, FIG. 3 is a sectional view taken along the line AA in FIG. FIG. 6 is an enlarged sectional view of the main part of the first housing with the sealing member removed, and is a view taken in the direction of arrow B in FIG. 5.

In the explanation of this figure, the direction parallel to the central axis Z of the shaft through hole, which is the rotational axis of the drive shaft 2, which will be described later, is referred to as the "axial direction", the direction perpendicular to the central axis Z is referred to as the "radial direction", and the central axis is referred to as the "radial direction". The direction around Z will be described as a "circumferential direction." Moreover, the above-mentioned "axial direction" will be described with the upper side in FIG. 3 as "one end side" and the lower side as "the other end side".

As shown in FIGS. 2 and 3, the control valve CV includes a cylindrical valve body 3 that is rotatably provided inside a housing 1, and a cylindrical valve body 3 that is housed in the housing 1 and that drives the valve body 3 through a drive shaft 2. The electric motor 4 includes an electric motor 4 that is part of a drive unit that rotates, and a reducer 5 that is housed in the housing 1 and is part of the drive unit that reduces and transmits the rotation of the electric motor.

As shown in FIG. 3, the housing 1 is formed into two parts in the axial direction, and includes a first housing 11 that accommodates the valve body 3 and the electric motor 4, and a first housing 11 that closes an opening at one end of the first housing 11. and a second housing 12 that accommodates the reduction gear 5. The first housing 11 and the second housing 12 are integrally formed of, for example, a heat-resistant and chemical-resistant synthetic resin, such as polyphenylene sulfide resin (PPS resin), which is a type of engineering plastic, and are connected by a plurality of bolts 13. Fixed.

The first housing 11 includes a hollow cylindrical valve body accommodating portion 21 that accommodates the valve body 3 and a hollow cylindrical motor accommodating portion that is attached in parallel with the valve body accommodating portion 21 and that accommodates the motor body of the electric motor 4. It has a section 22. The first housing 11 is fixed to a cylinder block (not shown) via a flange portion 24 (described later) by means of fixing means (not shown), such as a plurality of bolts.

The valve body accommodating portion 21 has one end in the axial direction closed by an end wall 23, and the other end opened to the outside. A flange portion 24 for attaching the first housing 11 to a cylinder block (not shown) is provided at the other end in the axial direction of the valve body housing portion 21 so as to extend outward in the radial direction. Further, a boss portion 25 in the shape of a cylinder with a lid is formed on the end wall 23 of the valve body accommodating portion 21 so as to protrude toward the second housing 12 side. A shaft through hole 26 through which the drive shaft 2 is inserted is formed in the center of the boss portion 25 along the axial direction.

As shown in FIGS. 3 to 6, this shaft through hole 26 has an inner peripheral surface formed in a stepped diameter shape along the axial direction, and has a minimum diameter portion 27 on the uppermost side in the figure and a minimum diameter portion 27 on the lower side. It has a small diameter part 28, a medium diameter part 29 below the small diameter part 28, and a large diameter part 30 at the lowermost end below the medium diameter part 29, and has a valve body housing part 21 and a large diameter part 30 which will be described later. The reduction gear accommodating section 31 communicates with the reduction gear accommodating section 31.

The shaft through hole 26 is formed together with the first housing 11 during, for example, injection molding, and the shaft through hole 26 is formed from the small diameter part 28 to the medium diameter part 29 and from the medium diameter part 29 to the large diameter part 30, respectively, in consideration of mold removal properties. The boundary portion is formed into a tapered shape. Further, as shown in FIG. 5, the shaft through hole 26 has a cross section of the inner circumferential surface in a direction perpendicular to the central axis Z of the shaft through hole 26, that is, a cross sectional shape that differs from region to region. That is, the inner circumferential surfaces of the minimum diameter portion 27 and the small diameter portion 28 are formed into approximately perfect circular shapes. However, the inner circumferential surface of the medium diameter portion 29 is formed into a noncircular portion 29a that is somewhat close to a heart shape, and the inner circumferential surface of the large diameter portion 30 is formed into a noncircular portion 30a that is even closer to a heart shape. Each of these non-circular portions 29a, 30a is close to a perfect circle and has an uneven shape of several tens of μm. The roundness is higher than that of the portion 30a.

Furthermore, a plurality of (three in this embodiment) protrusions 32a, 32b, and 32c protruding in the direction of the central axis Z are integrally provided on the inner circumferential surface of the medium diameter portion 29. As shown in FIGS. 5 and 6, the protrusions 32a to 32c are provided at equal intervals of approximately 120° in the circumferential direction on the inner circumferential surface of the medium diameter portion 29. Each of the protrusions 32a to 32c has an inner surface formed in an arcuate shape along the inner circumferential surface of the medium diameter portion 29, a circumferential width of about 2 mm, and a height of approximately 2 mm. It is set to 10 μm. In addition, the length (longitudinal length) of each of the protrusions 32a to 32c along the central axis Z direction is as shown in FIG. It is about 2/3 of the way down to the middle.

In addition, a pair of flat bearing portions for bearing two support shafts of a reducer 5, which will be described later, are formed upright on both ends of the end wall 23 of the valve body housing portion 21 in the radial direction (longitudinal direction). (not shown). A bearing hole for rotatably supporting each of the support shafts is formed through the pair of bearing parts.

The second housing 12 is formed in a concave shape in vertical section so as to extend over the valve body accommodating part 21 and the motor accommodating part 22 so as to be able to cover the valve body accommodating part 21 and the motor accommodating part 22 . A reduction gear accommodating portion 31 that accommodates the reduction gear 5 is formed by this concave internal space.

Although the electric motor 4 will be described without specific illustrations, the motor body is housed in the motor accommodating portion 22 with the output shaft facing the second housing 12 side. This electric motor 4 is attached to the opening edge of the motor accommodating portion 22 by a plurality of bolts via a flange (not shown) provided at the end of the motor body on the output shaft side so as to extend radially outward. Fixed. The electric motor 4 is controlled by a vehicle-mounted electronic controller (not shown), and rotates the valve body 3 according to the driving state of the vehicle, thereby ensuring appropriate distribution of cooling water to the radiator RD, etc. (see FIG. 1). It has been realized.

The speed reducer 5 will be described without specific illustrations, but it has two sets of staggered gears, a first gear and a second gear. The first gear includes a first screw gear that is provided coaxially with the output shaft of the electric motor 4 and rotates together with the output shaft, and a first support that is arranged orthogonally to the output shaft of the electric motor 4. The first helical gear is rotatably supported by the shaft and meshes with the first screw gear. The second gear includes a second screw gear WG2 that is rotatably supported by the second support shaft and rotates together with the first helical gear, and a second screw gear WG2 that is fixed to the drive shaft 2 and meshes with the second screw gear WG2. It is composed of two helical gears HG2. Here, the first helical gear HG2 and the second helical gear HG2 are composite gear members in which both cylindrical gears are arranged in series and integrated, and are inserted into both ends of this composite gear member. The first housing 11 is rotatably supported by a pair of bearing portions of the first housing 11 via first and second support shafts. With such a configuration, the rotational driving force output from the output shaft of the electric motor 4 is transmitted from the drive shaft 2 to the valve body 3 after being decelerated in two stages via the first gear and the second gear. It has become.

In the first housing 11 , a bottomed cylindrical motor housing part 22 for housing the motor body of the electric motor 4 therein is formed with an opening toward one end in the axial direction, adjacent to the valve body housing part 21 . ing.

Further, the first housing 11 is connected to a cylinder head (not shown) via a plurality of (three in this embodiment) flange portions 24 provided on the outer peripheral edge of the other axial end of the valve body accommodating portion 21. It is fixed to the side by means of fixing means, for example, a plurality of bolts. An introduction port E0 is formed on the inner peripheral side of each flange portion 24 as a communication port for communicating with the inside of a cylinder block (not shown) and introducing cooling water from the cylinder block side. That is, this introduction port E0 communicates with the opening on the other end side of the valve body accommodating portion 21, and cooling water can be introduced into the valve body accommodating portion 21 through the introduction port E0.

Further, a plurality of first to third discharge ports E1 to E3 having a substantially circular cross section and communicating the valve body housing part 21 with the outside are formed through the peripheral wall of the valve body housing part 21. Corresponding first to third pipes L1 to L3 are connected to each of these discharge ports E1 to E3, respectively. Note that the second discharge port E2 is formed to penetrate the first and second discharge ports E2 and E3 in a direction substantially perpendicular to the axis, as shown by a dashed line in FIG.

The first discharge port E1 is connected to, for example, the heater HT via the first pipe L1. The second discharge port E2 is connected to, for example, the oil cooler OC via the second pipe L2. The third exhaust port E3 is connected to, for example, the radiator RD via the third pipe L3. Note that the first to third discharge ports E1 to E3 correspond to communication ports according to the present invention.

Here, the first to third discharge ports E1 to E3 are located at different axial positions on the circumferential wall of the first housing 11, respectively, as shown in FIGS. are arranged at different circumferential positions on the top.

Furthermore, a sealing mechanism is provided on the inner peripheral side of the first to third discharge ports E1 to E3 to liquid-tightly seal between each of the discharge ports E1 to E3 and the valve body 3. This sealing mechanism includes cylindrical first to third sealing members S1 to S3 made of synthetic resin material, and an urging member that urges these first to third sealing members S1 to S3 toward the valve body 3 side. It is composed of first to third coil springs SP1 to SP3 made of metal. Furthermore, first to third seal rings SR1 to SR3 that can slide into contact with the first to third discharge ports E1 to E3 are provided on the outer peripheral sides of the first to third seal members S1 to S3.

The first to third sealing members S1 to S3 are formed of a predetermined fluororesin (in this embodiment, PTFE (polytetrafluoroethylene)), and are accommodated on the inner peripheral side of the first to third discharge ports E1 to E3. and are provided so as to be movable forward and backward toward the valve body 3 side. The first to third coil springs SP1 to SP3 are arranged with a predetermined set load between the first to third seal members S1 to S3 and the first to third piping L1 to L3, and are arranged with a predetermined set load between the first to third seal members S1 to S3, respectively. is biased toward the valve body 3 side.

The drive shaft 2 has a rod shape with a constant outer diameter, passes through the shaft through hole 26, is disposed astride the valve body housing part 21 and the reducer housing part 31, and has a minimum diameter part 27 at the upper end of the boss part 25. It is rotatably supported by a plane bearing B1 and a ball bearing B2 which are housed and held in the small diameter portion 28, respectively.

The valve body 3 is made of a predetermined hard resin material, and has a bottomed cylindrical shape with one axial end closed by an end wall 3a and the other end opened by an inlet E0. The valve body 3 is provided so that the introduction part M0 faces the introduction port E0 side, so that the cooling water is guided to the internal passage 28 formed on the inner peripheral side.

A recess 3b for receiving the boss 25 of the first housing 11 is formed in the center of the end wall 3a of the valve body 3, and a metal insert member 36 is embedded in the bottom of the recess 3b. . The valve body 3 is press-fitted and fixed to the drive shaft 2 via this insert member 36. On the other hand, the other end in the axial direction facing the introduction port E0 side is rotatably supported by a plain bearing B3 held on the inner peripheral side of the introduction port E0.

Further, on the circumferential wall of the valve body 3, a first opening is provided at an axial position corresponding to the first to third outlet ports E1 to E3 of the first housing 11, and is capable of communicating with the first to third outlet ports E1 to E3. ~Third openings M1 to M3 are formed through each other along the radial direction.

Further, an annular seal member 20 is interposed between the drive shaft 2 and the shaft through hole 26, and the seal member 20 provides a fluid-tight seal between the two and 26. As shown in FIG. 4, the sealing member 20 includes a cylindrical portion 33 formed of a hard metal material such as iron, and a cylindrical portion 33 that is provided inside the cylindrical portion 33 and slides on the outer circumferential surface of the drive shaft 2. and a sealing agent 35 filled between the inner circumferential surface of the medium diameter portion 29 and the outer circumferential surface of the cylindrical portion 33.

The cylindrical part 33 is formed in the shape of a covered cylinder with an open bottom side, and a shaft insertion hole 33b through which the drive shaft 2 is inserted is formed in the center of a circular cover wall 33a on the upper end side in FIG. There is. Further, the cylindrical portion 33 has an outer diameter slightly larger than the inner diameter of the medium diameter portion 29, and an outer peripheral surface is press-fitted into the non-circular portion 29a of the inner peripheral surface of the medium diameter portion 29 from the large diameter portion 30 side. be done. At this time, the cylindrical portion 33 is directly press-fitted into the arcuate inner surfaces of the three projections 32a to 32c provided on the inner peripheral surface of the medium diameter portion 29. Therefore, even if part of the outer peripheral surface of the cylindrical portion 33 contacts the non-circular portion 29a, the cylindrical portion 33 is basically supported at three points by the projections 32a to 32c.

FIG. 7 is a partially cutaway front view of the first housing showing a state in which the sealing member is press-fitted into the shaft through-hole, and FIG. 8 is a partial front view of the first housing showing a state in which the sealing member is press-fitted into the shaft through-hole. FIG.

As shown in FIG. 4, the seal portion 34 has a first seal 34a and a second seal 34b which are arranged in double layers, inside and outside. In terms of form, it is made of PTFE (polytetrafluoroethylene). The outer first seal 34a is formed into a substantially stepped cylindrical shape, and its vertical cross-sectional shape along the central axis Z is crank-shaped from the outside to the inside, and the inner circumferential surface of the lower tip 34c is aligned with the drive shaft 2. is arranged in slidable contact with the outer circumferential surface of. The inner second seal 34b is formed into a cylindrical shape along the inner periphery of the first seal 34a, and its upper end is bent outward into a diameter-expanding flange shape so as to fit into the stepped portion of the first seal 34a. The cylindrical inner circumferential surface is slidably abutted against the outer circumferential surface of the drive shaft 2 .

The sealing agent 35 is formed of a synthetic rubber that is initially fluid and is mainly made of latex, and is applied to approximately the center of the outer peripheral surface of the cylindrical portion 33 and the middle diameter portion 29, as shown in FIGS. 7 and 8. They are filled and arranged in an annular band shape at the boundary portion of the inner circumferential surface of the large diameter portion 30 .

The method for filling the sealant 35 is as follows: When the cylindrical part 33 holding the seal part 34 inside is press-fitted into the arcuate inner surfaces of the three protrusions 32a to 32c on the inner peripheral surface of the medium diameter part 29, The housing 1 is assembled with the housing 1 upside down (the other end in the Z-axis direction of the valve body accommodating portion 21 is on the upper side in the direction of gravity). is poured in a fluid state along the circumferential direction from the large diameter section 30 side to the middle diameter section 29 side. As a result, the sealing agent 35 flows in the axial direction along the inner circumferential surface of the medium diameter portion 29 to near the tips of each of the protrusions 32a to 32c, and then becomes an annular semi-solidified state over time and functions as a seal. demonstrate.

Further, in this embodiment, the sealant 35 is not filled up to both sides of each of the protrusions 32a to 32c, but is further applied from the boundary between the large and medium diameter parts 29 and 30 to each of the protrusions 32a to 32c. It is also possible to fill both sides of 32c. This makes it possible to further improve the sealing performance between the cylindrical portion 33 and the shaft through hole 26.

Therefore, the seal portion 34 of the seal member 20 and the sealant 35 prevent the cooling water in the valve body accommodating portion 21 from flowing into the second housing 12 through the shaft through hole 26.
(Operation and effect of control valve in this embodiment)
The control valve CV configured as described above supplies cooling water to the first pipe L1 by controlling the valve body 3 to a position in the circumferential direction where at least a portion of the first opening M1 and the first discharge port E1 overlap. distribute. Similarly, the control valve CV distributes cooling water to the second pipe L2 by controlling the valve body 3 to a position in the circumferential direction where at least a portion of the second opening M2 and the second discharge port E2 overlap. The valve body 3 is controlled to a position in the circumferential direction where at least a portion of the third opening M3 and the third discharge port E3 overlap, thereby distributing cooling water to the third pipe L3. In addition, when distributing this cooling water, by changing the overlapping degree (overlapping area) between the first to third openings M1 to M3 and the first to third discharge ports E1 to E3, the cooling water at the time of distribution is changed. The flow rate changes.

As mentioned above, in the conventional control valve CV, the radial cross-sectional shape of the shaft through hole is formed into a substantially perfect circular shape, so the metal cylindrical part mentioned above is press-fitted here. Then, the load stress of this press-fitting is applied to the entire inner circumferential surface of the shaft through-hole, causing cracks to occur in a part of the inner circumferential surface of the shaft through-hole, and depending on the case, there is a fear that the housing may be damaged.

In particular, internal combustion engines experience large temperature differences depending on the vehicle operating environment, and the large difference in thermal expansion between synthetic resin and metal materials can generate stress loads on the inner circumferential surface of the shaft through-hole, causing cracks. It becomes easier. As a result, there was a risk that the sealing performance of the sealing member would deteriorate.

On the other hand, in this embodiment, the inner peripheral surface of the medium diameter part 29 of the shaft through hole 26 of the first housing 11 made of synthetic resin is made into a non-circular part 29a, so that the inner peripheral surface of this medium diameter part 29 is When the metal cylindrical portion 33 is press-fitted into the surface, the stress of the tensile load acting on the inner circumferential surface of the medium-diameter portion 29 during press-fitting is dispersed and alleviated by the non-circular portion 29a. As a result, it is possible to sufficiently suppress the occurrence of cracks in the inner circumferential surface of the shaft through hole 26 (medium diameter portion 29), that is, in the first housing 11, due to the load stress caused by the press fitting.

In particular, since three protrusions 32a to 32c are provided on the inner circumferential surface of the medium diameter portion 29, when the cylindrical portion 33 is press-fitted into the medium diameter portion 29 as described above, the load of this press-fitting is The stress is received not by the entire circumference of the inner peripheral surface of the medium diameter portion 29 but by each of the protrusions 32a to 32c. Therefore, this load stress can be further reduced. As a result, the risk of cracking or damage to the inner circumferential surface of the medium diameter portion 29 can be further suppressed. Furthermore, even if the inner circumferential surface of the medium diameter portion 29 of the shaft through hole 26 remains the non-circular portion 29a, the stress load of press-fitting can be managed by each of the protrusions 32a to 32c, which further reduces the risk of cracking, etc. can.

In addition, even if the temperature difference due to the usage environment of the vehicle increases and a large difference in thermal expansion occurs between the synthetic resin material and the metal material, the load stress generated on the inner circumferential surface of the shaft through hole 26 can be reduced. It is possible to suppress the occurrence of cracks on the inner peripheral surface.

Moreover, in addition to the seal member 20, a sealing agent 35 is filled between the cylindrical portion 33 and the shaft through hole 26 (the medium diameter portion 29 and the large diameter portion 30), so that the inside of the shaft through hole 26 is filled with a sealant 35. Even if the inner circumferential surface of the diameter portion 29 remains the non-circular portion 29a, leakage of cooling water from between the inner circumferential surface of the shaft through hole 26 and the outer circumferential surface of the cylindrical portion 33 can be suppressed. In particular, since the sealant 35 has fluidity at the initial stage of use, it freely enters between the inner peripheral surface of the medium diameter portion 29 (non-circular portion 29a) and the outer peripheral surface of the cylindrical portion 33. Can be filled according to the shape between the circumferential surfaces. Therefore, it becomes possible to sufficiently enhance the sealing function between the medium diameter portion 29 and the cylindrical portion 33.

Furthermore, when the sealant 35 is filled between each of the protrusions 32a to 32c of the medium diameter portion 29, the liquid tightness becomes even higher, and the space between the shaft through hole 26 and the cylindrical portion 33 becomes more liquid-tight. This makes it possible to more effectively suppress leakage of cooling water from.

In this embodiment, since three protrusions 32a to 32c are provided, centering between the shaft through hole 26 and the drive shaft 2 is facilitated.

(Second embodiment)
FIG. 9 shows a second embodiment of the present invention, in which the structure of the seal member 20 is changed.

That is, the sealing member 20 includes a fixing base 40 formed of an elastically deformable synthetic rubber material, a metal cylindrical part 41 as a core material embedded inside the fixing base 40, and a fixing base 40 formed of an elastically deformable synthetic rubber material. It has a seal portion 42 that protrudes from one axial end portion (upper end portion in the figure) of the base portion 40 toward the center axis Z side.

The fixing base 40 is formed of a synthetic rubber material into a cylindrical shape with a predetermined thickness, and one end (upper end in the figure) 40a in the direction of the central axis Z is bent at a right angle toward the sealing portion 42 side. Further, the fixing base 40 is press-fitted into the inner peripheral surface of the medium diameter portion 29 of the shaft through hole 26, including the non-circular portion 29a, and is provided at the boundary between the medium diameter portion 29 and the small diameter portion 28. The maximum press-fitting position is regulated by the one end 40a abutting against the stepped surface 29b.

The cylindrical part 41 is formed into a cylindrical shape by, for example, a ferrous metal material, and one end 41a in the axial direction is bent into a flange shape toward the center axis Z direction and embedded in the one end 40a of the fixing base 40. It is.

The seal portion 42 protrudes from one end 40a of the fixing base 40 toward the center axis Z side, and is formed by bending downward in the figure from the first seal lip 42a on the upper end side in the figure into a substantially L-shape from the one end 40a. It has a second seal lip 42b. The tip of the first seal lip 42a and the tip of the bent portion of the second seal lip 42b are slidably provided in elastic contact with the outer peripheral surface of the drive shaft 2.

Therefore, according to the second embodiment, since the entire sealing member 20 except the cylindrical portion 41 is made of synthetic rubber, when it is press-fitted into the shaft through-hole 26, the outer circumferential surface of the fixing base 40 is exposed to the shaft through-hole. 26 (medium diameter portion 29), and is fixed in elastic contact with the entire inner peripheral surface including the non-circular portion 29a. Therefore, a large stress load due to the press fitting does not act on the inner circumferential surface of the shaft through hole 26 or the non-circular portion 26a. Therefore, the occurrence of cracks, damage, etc. on the inner circumferential surface of the shaft through hole 26 can be sufficiently suppressed.

Moreover, the fixing base 41 of the seal portion 20 comes into elastic contact with the stepped surface 26b together with the inner peripheral surface including the non-circular portion 26a of the medium diameter portion 29, and the first and second seal lips 42a, 42b are connected to the outer periphery of the drive shaft 2. Since it makes elastic contact with the surface, it becomes possible to effectively seal between the shaft through hole 26 and the drive shaft 2.

Furthermore, in this embodiment, since the overall structure of the seal member 20 is simple, the manufacturing cost can be reduced, and the work of assembling it into the shaft through hole 26 is easy, so that the efficiency of these works can be improved.

The control valve CV according to the present invention is not limited to the configuration of the above-described embodiments, and can be freely adapted to the specifications of the internal combustion engine (engine) to which it is applied, as long as it can achieve the effects of the present invention. It can be changed to

In the embodiment, the control valve CV is applied to a cooling water circulation system as an example of application, but the control valve CV can be applied not only to cooling water but also to various fluids such as lubricating oil.

Further, in the first embodiment, there are three protrusions 32a to 32c, but the number may be increased to four, five, or more, or there may be a circle around the entire inner peripheral surface of the medium diameter portion 29. It is also possible to form it in a ring shape.

Further, each of the protrusions 32a to 32c is not necessarily required, since the object of the present invention can be achieved as long as the non-circular portions 29a and 30a of the shaft through hole 26 are present. However, by providing the protrusions 32a to 32c, together with the effect of the non-circular portion 29a, the stress on the inner peripheral surface of the shaft through hole 26 when the seal member 20 (cylindrical portion 33) is press-fitted is reduced. It becomes possible to reduce the amount of stress and to manage stress easily.

Further, the non-circular portion 29a is not limited to a heart shape, and may be a polygon such as a triangular shape or a quadrangular shape, or a gourd shape, and is not limited to the shape.

Further, the sealing member 20 is not limited to the structure of the first and second embodiments, and can be further modified.

Further, in the embodiment described above, the valve body is provided with three openings consisting of the first to third openings M1 to M3, but at least one opening in the peripheral wall of the valve body is provided. The openings M1 to M3 are not limited to the first to third openings M1 to M3.

As the control valve based on the embodiment described above, for example, the following aspects can be considered.

In one embodiment, the housing is made of synthetic resin and has a valve body housing, a communication port that opens into the valve body housing for introducing and discharging fluid, and a shaft through hole into which the drive shaft is inserted. and,
a valve body that is rotatably accommodated in the valve body accommodating portion around a rotation axis and that can open and close the communication port depending on the rotational position;
a drive unit having the drive shaft inserted into the shaft through hole and capable of rotating the valve body;
a sealing member disposed between an inner circumferential surface of the shaft through hole and an outer circumferential surface of the drive shaft;
Equipped with
The shaft through hole has a non-circular portion having a non-circular cross section in a direction perpendicular to the central axis of the shaft through hole,
The seal member includes a cylindrical portion made of a harder material than the housing that is press-fitted into the non-circular portion of the shaft through hole, and a seal portion that is provided on the inner periphery of the cylindrical portion and slides on the drive shaft. , a sealant disposed between an inner periphery of the shaft through hole and an outer periphery of the cylindrical portion.

According to this aspect of the invention, by forming a part of the shaft through hole of the synthetic resin housing into a non-circular part, load stress is distributed when the cylindrical part of the hard material is press-fitted into the non-circular part. It can be relaxed. This makes it possible to suppress the occurrence of cracks or damage to the housing due to the press-fitting load. Furthermore, by disposing the sealant, leakage of fluid from between the inner circumferential surface of the shaft through hole and the outer circumferential surface of the cylindrical portion can be suppressed.

More preferably, the shaft through hole has a plurality of protrusions on its inner circumferential surface that protrude radially toward the central axis of the shaft through hole and into which the cylindrical portion is press-fitted.

According to this aspect of the invention, when the cylindrical part is press-fitted into the shaft through-hole, the pressure is received not by the entire circumference of the shaft through-hole but by the plurality of protrusions, so that this press-fitting stress can be reduced, and cracks and Risks such as damage can be suppressed. Further, even if a portion of the inner circumferential surface of the shaft through hole remains non-circular, the press-fitting load can be managed by each protrusion, thereby further reducing the risk of breakage.

More preferably, the shaft through hole has a plurality of protrusions on its inner circumferential surface that protrude radially toward the central axis of the shaft through hole and into which the cylindrical portion is press-fitted.

More preferably, the plurality of protrusions are formed in a part of the shaft through hole in the central axis direction, and a part of the outer peripheral surface of the cylindrical part is held by the plurality of protrusions.

According to this aspect of the invention, the cylindrical portion is press-fitted and fixed to a portion in the direction of the rotating shaft by each projection of the shaft through hole.

More preferably, the sealant is a synthetic rubber material, and is disposed offset from the plurality of projections in the central axis direction of the shaft through hole. By shifting the sealant in the direction of the center axis of the shaft through hole, liquid tightness (sealability) due to the sealant can be ensured.

More preferably, the inner circumferential surface of the shaft through hole has an inner diameter formed in a stepped diameter shape from one end in the central axis direction of the shaft through hole to the other end, and from a small diameter portion to a medium diameter portion and a large diameter portion. As it goes, it becomes a non-circular part and the roundness becomes lower, and each of the protrusions is provided in the middle diameter part where the roundness is low, and the seal is attached to the large diameter part and the middle diameter part where the roundness is low. place the agent,
At least a portion of the sealant is located at a position offset from each of the protrusions to one side in the central axis direction of the shaft through hole.

The inner circumferential surface of the shaft through-hole becomes non-circular and less round as it goes from the small diameter part to the large diameter part. Due to this shape, each protrusion is provided in areas with high roundness and the sealant is placed in areas with low roundness, which increases the accuracy of press-fitting the cylindrical part with each protrusion, and seals. Improves liquid tightness (sealing performance) due to the agent.

More preferably, the control valve is characterized in that a portion of the sealant is also disposed between the respective protrusions in the circumferential direction of the shaft through hole.

After the sealant is filled between the shaft through hole and the cylindrical portion, it flows and flows between the respective protrusions. Thereby, the sealing performance between the shaft through hole and the cylindrical portion can be further improved.

More preferably, the cylindrical portion is made of metal.

Since the cylindrical part is made of metal, the housing is likely to crack or break due to the stress load when it is press-fitted into the shaft through-hole, but as mentioned above, the inner peripheral surface of the shaft through-hole is Since it is formed in a circular shape, the press-fitting stress of the cylindrical portion can be dispersed and relaxed, so that the occurrence of cracks and damage to the housing can be effectively suppressed.

Another preferable embodiment is a synthetic resin material having a valve body accommodating portion, a communication port opening into the valve body accommodating portion for introducing and discharging fluid, and a shaft through hole into which a drive shaft is inserted. housing and
a valve body that is rotatably accommodated in the valve body accommodating portion around a rotation axis and that can open and close the communication port depending on the rotational position;
a drive unit having the drive shaft inserted into the shaft through hole and capable of rotating the valve body;
an inner circumferential surface of the shaft through hole, an outer circumferential surface of the drive shaft, and a sealing member disposed between;
The shaft through hole has a non-circular portion having a non-circular cross section in a direction perpendicular to the central axis of the shaft through hole,
The sealing member includes a fixing base whose elastically deformable outer peripheral part is press-fitted into the non-circular part and which has a metal cylindrical part inside, and an inner circumference of the fixing base, and the drive shaft is and a slidable seal portion, and the fixing base and the seal portion seal between the non-circular portion of the shaft through hole and the outer circumferential surface of the drive shaft.

According to this aspect of the invention, even if the fixing base has a metal cylindrical part inside, when the fixing base is press-fitted into the shaft through-hole, the outer peripheral part comes into elastic contact with the non-circular part of the shaft through-hole. Cracks, damage, etc. can be sufficiently suppressed, and together with the seal portion, it becomes possible to effectively seal between the drive shaft and the shaft through hole.

CV... Control valve, 1... Housing, 2... Drive shaft, 11... First housing, 12... Second housing, 20... Seal member, 21... Valve body housing part, 26... Shaft through hole, 27... Minimum diameter part, 28... Small diameter part, 29... Medium diameter part, 29a... Non-circular part, 30... Large diameter part, 30a... Non-circular part, 33... Cylindrical part, 34... Seal part, 34a... First seal part, 34b... Third 2 seal part, 40...fixing base, 41...cylindrical part, 42...seal part, 42a...first seal lip, 42b...second seal lip, E0...inlet (communication port), E2...second discharge port (Communication port), E3...Third discharge port (communication port), 3...Valve body, M0...Introduction part, M1...First opening, M3...Third opening, Z...Center axis of the axis through hole.

Claims (8)

A synthetic resin housing having a valve body housing part, a communication port opening into the valve body housing part for introducing and discharging fluid, and a shaft through hole into which a drive shaft is inserted;
a valve body that is rotatably accommodated in the valve body accommodating portion around a rotation axis and that can open and close the communication port depending on the rotational position;
a drive unit having the drive shaft inserted into the shaft through hole and capable of rotating the valve body;
a sealing member disposed between an inner circumferential surface of the shaft through hole and an outer circumferential surface of the drive shaft;
Equipped with
The shaft through hole has a non-circular portion having a non-circular cross section in a direction perpendicular to the central axis of the shaft through hole,
The seal member includes a cylindrical portion made of a harder material than the housing that is press-fitted into the non-circular portion of the shaft through hole, and a seal portion that is provided on the inner periphery of the cylindrical portion and slides on the drive shaft. A control valve comprising: a sealant disposed between an inner periphery of the shaft through hole and an outer periphery of the cylindrical portion. The control valve according to claim 1,
The control valve is characterized in that the shaft through hole has a plurality of protrusions on an inner circumferential surface thereof that protrude radially toward the central axis of the shaft through hole and into which the cylindrical portion is press-fitted. The control valve according to claim 2,
The plurality of protrusions are formed in a part of the shaft through hole in the central axis direction,
The control valve is characterized in that the cylindrical portion has a part of its outer peripheral surface held by the plurality of protrusions. The control valve according to claim 3,
The control valve is characterized in that the sealant is made of a synthetic rubber material and is disposed offset from the plurality of protrusions in the direction of the center axis of the shaft through hole. The control valve according to claim 4,
The inner circumferential surface of the shaft through-hole is formed in a stepped diameter shape from one end in the central axis direction of the shaft through-hole to the other end, and becomes non-uniform as it goes from the small diameter part to the medium diameter part and the large diameter part. The protrusions are provided in the medium diameter portion, which becomes a circular portion and has low circularity, and the sealing agent is placed in the large diameter portion and the medium diameter portion, which have low circularity. ,
The control valve is characterized in that at least a portion of the sealant is located at a position offset from each of the protrusions to one side in the central axis direction of the shaft through hole. The control valve according to claim 5,
A control valve characterized in that a portion of the sealing agent is also disposed between each of the protrusions in the circumferential direction of the shaft through hole. The control valve according to any one of claims 1 to 6,
A control valve characterized in that the cylindrical portion is made of a ferrous metal material. A synthetic resin housing having a valve body housing part, a communication port opening into the valve body housing part for introducing and discharging fluid, and a shaft through hole into which a drive shaft is inserted;
a valve body that is rotatably accommodated in the valve body accommodating portion around a rotation axis and that can open and close the communication port depending on the rotational position;
a drive unit having the drive shaft inserted into the shaft through hole and capable of rotating the valve body;
a sealing member disposed between an inner circumferential surface of the shaft through hole and an outer circumferential surface of the drive shaft;
Equipped with
The shaft through hole has a non-circular portion having a non-circular cross section in a direction perpendicular to the central axis of the shaft through hole,
The sealing member includes a fixing base whose elastically deformable outer peripheral part is press-fitted into the non-circular part and which has a metal cylindrical part inside, and an inner circumference of the fixing base, and the drive shaft is A control valve comprising: a slidable seal portion, the fixing base portion and the seal portion sealing between the non-circular portion of the shaft through hole and the outer circumferential surface of the drive shaft.

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