JP2007039013A - Pressure generation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact pressure generation device, for example, a pressure (pneumatic pressure) generation device capable of supplying the pressurized air in a tire air chamber of a wheel. <P>SOLUTION: A pressure generation device AP1 includes an axle hub 20 that has a rotating shaft section 21A rotatably supported in a non-rotatable circular tube support section 11 through bearings 12, 13, a piston 30 that is co-rotatably assembled in the rotating shaft section 21A so as to be able to perform pumping action and forms a pump chamber Ro, a cam member 41 and a cam follower 42 that convert rotational motion of the axle hub 20 relative to the circular tube support section 11 into pumping action of the piston 30, a suction path 21d that is formed in the axle hub 20 and is capable of sucking air into the pump chamber Ro, and a discharge path 21e that is formed in the axle hub 20 and is capable of discharging air from the pump chamber Ro. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides pressurized air to the tire air chamber of a wheel including a pressure generator, for example, a wheel that is supported by a wheel hub of a vehicle and is rotatable and mounted on the wheel to form a tire air chamber. The present invention relates to a pressure (air pressure) generating device that can be supplied.

This type of pressure generating device is disclosed in Patent Document 1 below, for example. In the pressure generating device (tire pressure adjusting device) described in Patent Document 1, a pump unit that reciprocates in the axial direction of an axle is disposed on a member that rotates together with an axle that rotationally drives an axle hub of the vehicle. One end of the piston of the pump unit is brought into contact with the inclined surface of the cam member that does not rotate with respect to the rotation of the wheel. Therefore, the pump function is obtained by reciprocating the piston of the pump unit as the wheel rotates.
JP-A-11-139118

  By the way, in the configuration of the pressure generating device described in Patent Document 1 described above, the axis of the piston in the pump unit is eccentric by a predetermined amount radially outward with respect to the axis of the axle. For this reason, the diameter of the inclined surface of the cam member in contact with one end of the piston must be equal to or larger than the amount corresponding to the amount of radial eccentricity of the axial center of the piston. There is difficulty in mounting. Moreover, in order to balance the wheel balance (rotation balance), it is necessary to provide a counterweight (balance weight) for offsetting the weight of the pump unit, which also makes it difficult to reduce the size of the pressure generating device. It is said.

  The present invention has been made to cope with the above-described problem, and a rotating body including a rotating shaft portion that is rotatably supported via a bearing in a non-rotatable support member. A pump operating body that is assembled so as to be integrally rotatable and pump operable with respect to the rotating shaft portion of the rotating body to form a pump chamber, and the rotational motion of the rotating body with respect to the support member A motion converting mechanism for converting the fluid into a pump, a suction passage formed in the rotating body and capable of sucking fluid into the pump chamber, and a discharge passage formed in the rotating body and capable of discharging fluid from the pump chamber. (Invention according to claim 1) is characterized.

  In this case, the rotating body may be a vehicle axle hub, the support member may be a knuckle that rotatably supports the axle hub, and the fluid may be air (the invention according to claim 2). is there. Further, the pump operating body is a piston that is assembled so as to be integrally rotatable and reciprocally movable with respect to the rotating shaft portion, and the motion conversion mechanism converts the rotational motion of the rotating body with respect to the support member to the reciprocating motion of the piston. It is also possible to use a motion conversion mechanism (invention according to claim 3).

  In this case, the rotating shaft portion is coaxially formed with a cylinder bore that accommodates the piston in a reciprocating manner in the axial direction, and the piston can move the rotating shaft portion in the axial direction. A load transmission element that penetrates in a rotational direction so as not to move is provided, and the motion conversion mechanism is configured by a cam follower provided at the outer end in the piston radial direction of the load transmission element and a cylindrical cam assembled in the support member. It is also possible to constitute (the invention according to claim 4).

  Further, the piston is formed in a cylindrical shape and is assembled to the outer periphery of the rotating shaft portion so as to be integrally rotatable and reciprocally movable in the axial direction, and the support member and the rotating shaft portion are provided with the support A cylinder member that is provided integrally with the member and accommodates the piston so as to be capable of reciprocating in the axial direction is interposed, and the motion conversion mechanism is set between the piston and the cylinder member. (Invention according to item 5) is also possible.

  The rotary shaft portion is formed with a cylinder inner hole that accommodates the piston so as to be reciprocally movable in the radial direction of the rotary shaft portion, and the outer shaft protrudes outward from the cylinder inner hole of the piston. It is also possible that the motion conversion mechanism is constituted by a cam follower provided at an end and a cylindrical cam assembled in the support member (invention according to claim 6).

  In the pressure generating device according to the present invention described above, when the rotating body rotates with respect to the support member, the rotational motion is converted into the pump operation of the pump operating body by the motion conversion mechanism, and the pump operating body pumps. As a result, the volume of the pump chamber increases and decreases, and the fluid sucked into the pump chamber through the suction passage is discharged from the pump chamber through the discharge passage.

  By the way, in the pressure generating device according to the present invention, the rotating shaft portion of the rotating body is rotatably supported through a bearing in the support member, and a pump operating body (piston) is supported on the rotating shaft portion of the rotating body. The pump chamber is formed so as to be integrally rotatable and pump operable. For this reason, it is not necessary to provide a balance weight on the rotating body in order to balance the rotational balance, and the pressure generating device can be configured compactly in the support member. The generation device can be downsized.

  In carrying out the present invention, the rotary shaft portion is rotatably supported by the support member via a first bearing and a second bearing that are arranged at predetermined intervals in the axial direction. The invention according to (1) is also possible. In this case, it is possible to ensure the support rigidity of the rotating body with respect to the support member by the first bearing and the second bearing. In this case, the motion conversion mechanism may be interposed between the first bearing and the second bearing (the invention according to claim 8). In this case, the space between the first bearing and the second bearing can be effectively utilized as the accommodation space for the motion conversion mechanism, and the pressure generating device can be configured compactly.

  In carrying out the present invention, a first seal member and a second seal member for sealing the first bearing and the second bearing are provided between the rotary shaft portion and the support member. It is also possible to interpose the bearing in the axial direction (invention according to claim 9). In this case, the first bearing and the second bearing can be sealed by the first seal member and the second seal member, and the motion conversion mechanism can be sealed. As a result, the pressure generator can be made more compact and lower in cost.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a pressure generating device according to the present invention, and the pressure generating device AP1 of the first embodiment can supply pressurized air to a tire air chamber (not shown) of a wheel in a vehicle. A pneumatic pressure generating device, including a cylindrical support portion 11 that is a part of a knuckle as a support member, an axle hub 20 as a rotating body, and a columnar piston 30 as a pump operating body, and a cylinder of the axle hub 20 A cam member 41 and a cam follower 42 as a motion conversion mechanism for converting a rotational motion with respect to the support portion 11 into a reciprocating motion of the piston 30 and a rod 43 for rotatably supporting the cam follower 42 are provided.

  The cylindrical support portion 11 is formed in a cylindrical shape centered on the axis line Lo, and cannot rotate about the axis line Lo. Inside the rotation shaft portion 21A of the axle hub 20, a pair of bearings 12 and 13 and a pair are provided. Are supported in a liquid-tight manner in a rotatable manner around the axis Lo. The pair of bearings 12 and 13 are disposed a predetermined distance apart in the axial direction (direction along the axis line Lo) of the rotating shaft portion 21A, and are cylindrically supported so as to sandwich the cam member 41 in the axial direction of the rotating shaft portion 21A. It is interposed between the part 11 and the rotating shaft part 21A, and the axle hub 20 is rotatable with respect to the cylindrical support part 11, that is, the knuckle. The pair of annular seal members 14 and 15 are arranged a predetermined distance apart in the axial direction of the rotating shaft portion 21A, and are cylindrically supported so as to sandwich the cam member 41 and the bearings 12 and 13 in the axial direction of the rotating shaft portion 21A. It is interposed between the part 11 and the rotating shaft part 21A, and seals between the cylindrical support part 11 and the rotating shaft part 21A in a liquid-tight manner.

  The axle hub 20 includes a hub main body 21 and a sleeve 22 screwed in a liquid-tight manner to the outer periphery of the lower end portion of the hub main body 21. The hub body 21 includes a rotating shaft portion 21A and an annular flange portion 21B. The rotating shaft portion 21A is formed with a pair of axial long holes 21a and a cylinder inner hole 21b, and the annular flange portion 21B includes a wheel. A mounting portion 21c (not shown) (not shown) is formed, and a suction passage 21d and a discharge passage 21e are formed in the rotating shaft portion 21A and the annular flange portion 21B.

  The pair of axially elongated holes 21a are guide means for guiding the piston 30, the cam follower 42, and the rod 43 so as to be able to rotate integrally with the axle hub 20 and reciprocate in the axial direction. It is formed at intervals of 180 degrees in the direction. The cylinder inner hole 21b accommodates the piston 30, and the piston 30 forms a pump chamber Ro in the rotating shaft portion 21A. The intake passage 21d is for introducing (inhaling) air into the pump chamber Ro, and an intake check valve Vi is interposed therein. The discharge passage 21e is used to lead out (discharge) air from the pump chamber Ro, and a discharge check valve Vo is interposed therein. The pressurized air discharged from the pump chamber Ro can be supplied to a wheel tire air chamber (not shown) assembled to the axle hub 20.

  The piston 30 is inserted into the cylinder inner hole 21b of the rotating shaft portion 21A of the axle hub 20 via a pair of annular seal members 31 and 32, and is coaxially and integrally rotated with respect to the rotating shaft portion 21A of the axle hub 20. It is assembled so that it can move back and forth in the axial direction. The piston 30 is formed with an annular groove 30a and a through hole 30b extending in the piston radial direction. The pair of annular seal members 31, 32 are disposed a predetermined amount apart in the piston axial direction, and are interposed between the piston 30 and the rotary shaft portion 21 </ b> A at the axial end of the piston 30. The rotation shaft portion 21A is hermetically and liquid-tightly sealed.

  The annular groove 30a is formed on the outer periphery of the piston 30 between the pair of annular seal members 31, 32, and forms an annular space R1 between the piston 30 and the rotary shaft portion 21A. The annular space R1 communicates with the annular space R2 formed between the pair of annular seal members 14 and 15 through the respective axial long holes 21a formed in the rotating shaft portion 21A. Each annular space R1, R2 does not change in volume even when the piston 30 reciprocates in the axial direction, and is sealed by four seal members 14, 15, 31, 32. The annular spaces R1, R2, etc. are oil chambers for storing a required amount of lubricating oil, and bearings 12, 13, a cam member 41, a cam follower 42, etc. are accommodated in the oil chambers.

  The cam member 41 is a cylindrical cam provided integrally with the cylindrical support portion 11 (not axially movable and non-rotatable), and includes a pair of cam sleeves 41A and 41B connected in the axial direction. Are arranged coaxially with respect to the rotating shaft portion 21A. The cam member 41 has an annular cam portion 41a that varies in the axial direction, and the cam portion 41a is a cam groove to which a cam follower 42 is fitted. The cam portion 41a has a cam surface that receives an axial load (a vertical load in the drawing) and a radial load (a horizontal load in the drawing) from the cam follower 42, and the cam surface has a V-shaped cross section. It is a shape and is formed with an even number of cycles (for example, two cycles) in the circumferential direction of the rotating shaft portion 21A.

  The cam follower 42 is a ball that is rotatably assembled to the piston radial outer end of the rod 43, and is engaged with a cam portion (cam groove) 41a at a piston radial end perpendicular to the axis Lo. By rotating relative to the member 41, it can move together with the rod 43 in the axial direction (vertical direction in the figure) of the rotary shaft portion 21A. The rod 43 is a load transmitter that is assembled to the through-hole 30b of the piston 30 so as to be movable in the radial direction of the piston 30 (the axial direction of the through-hole 30b), and is connected to the axially long hole 21a of the rotary shaft portion 21A. On the other hand, it penetrates through the rotation shaft portion 21A so that it can move in the axial direction and cannot move in the rotation direction.

  In the pressure generating device AP1 of the first embodiment configured as described above, when the axle hub 20 rotates with respect to the cylindrical support portion 11, the piston 30, the rod 43, and the cam follower 42 rotate integrally with the axle hub 20. Thus, it rotates relative to the cam member 41 and moves in the axial direction. For this reason, the rotational movement of the axle hub 20 can be converted into the reciprocating motion of the piston 30, the volume of the pump chamber Ro can be increased or decreased by the reciprocating motion of the piston 30, and the suction check valve Vi is interposed. Air can be sucked into the pump chamber Ro through the suction passage 21d, and the air can be discharged from the pump chamber Ro through the discharge passage 21e provided with the discharge check valve Vo. This discharge air (pressurized air) is used as the axle hub. 20 can be supplied to a tire air chamber (not shown) of a wheel assembled to the wheel 20.

  By the way, in the pressure generating device AP1 of the first embodiment, the rotating shaft portion 21A of the axle hub 20 is rotatably supported in the cylindrical support portion 11 via the bearings 12 and 13, and the rotation of the axle hub 20 is performed. The piston 30 is coaxially mounted on the shaft portion 21A, is integrally rotatable, and is reciprocally movable in the axial direction (pump operation is possible) to form a pump chamber Ro exposed to the rotation shaft portion 21A. Therefore, it is not necessary to provide a balance weight in the axle hub 20 in order to balance the rotational balance, and it is possible to make the pressure generating device AP1 compact in the cylindrical support portion 11. Thus, the pressure generating device AP1 can be downsized.

  Further, in the pressure generating device AP1 of the first embodiment, the rotating shaft portion 21A of the axle hub 20 is cylindrical through a pair of bearings 12 and 13 arranged at predetermined intervals in the axial direction of the rotating shaft portion 21A. The support part 11 is rotatably supported. For this reason, it is possible to ensure the support rigidity of the axle hub 20 with respect to the cylindrical support portion 11 by the pair of bearings 12 and 13. Further, a cam member 41 and a cam follower 42 as a motion conversion mechanism are interposed between the pair of bearings 12 and 13. For this reason, the space between the pair of bearings 12 and 13 can be effectively used as the accommodation space of the motion conversion mechanism, and the pressure generating device AP1 can be configured compactly.

  Further, in the pressure generating device AP1 of the first embodiment, the cam member 41 and the bearings 12 and 13 are disposed in the axial direction of the rotating shaft portion 21A between the rotating shaft portion 21A of the axle hub 20 and the cylindrical support portion 11. A pair of annular seal members 14 and 15 are provided to seal the pair of bearings 12 and 13 so as to be sandwiched therebetween. Therefore, the pair of bearings 12 and 13 can be sealed by the pair of annular seal members 14 and 15, and the cam member 41 and the cam follower 42 as a motion conversion mechanism can be sealed. The pressure generator AP1 can be made compact and cost-effective by sharing the members.

  Further, in the pressure generating device AP1 of the first embodiment, the pair of annular seal members 31, 32 that liquid-tightly seal between the piston 30 and the rotating shaft portion 21A of the axle hub 20 are separated by a predetermined amount in the axial direction. A pair of annular seal members 14 and 15 for liquid-tightly sealing between the rotating shaft portion 21A of the axle hub 20 and the cylindrical support portion 11 are disposed apart from each other by a predetermined amount in the axial direction. The bearings 12 and 13, the cam member 41, the cam follower 43, and the like are accommodated in an oil chamber (annular space R 1 and R 2) that is sealed by the seal members 14, 15, 31, and 32 and accommodates a required amount of hydraulic oil. ing. For this reason, the lubricity of each sliding part is ensured, and it is possible to reduce sliding resistance and improve durability at each sliding part.

  FIG. 2 shows a second embodiment of the pressure generating device according to the present invention, and the pressure generating device AP2 of the second embodiment can supply pressurized air to a tire air chamber (not shown) of a wheel in a vehicle. The air pressure generating device includes a cylindrical support 111 that is a part of a knuckle as a support member, an axle hub 120 as a rotating body, a cylindrical piston 130 as a pump operating body, and a cylinder of the axle hub 120. A cylindrical cam 141 and a cam follower 142 as a motion conversion mechanism for converting a rotational motion with respect to the support portion 111 into a reciprocating motion of the piston 130, and a cylinder member 150 that houses the piston 130 are provided.

  The cylindrical support portion 111 is formed in a cylindrical shape centered on the axis line Lo, and cannot rotate about the axis line Lo, and the rotation shaft portion 121A of the axle hub 120 includes a pair of bearings 112 and 113 inside. The ring-shaped sealing members 114 and 115 are rotatably supported around the axis Lo and are liquid-tightly supported. The pair of bearings 112 and 113 are arranged a predetermined distance apart in the axial direction (direction along the axis line Lo) of the rotating shaft 121A, and are cylindrically supported so as to sandwich the cylinder member 150 in the axial direction of the rotating shaft 121A. It is interposed between the portion 111 and the rotating shaft portion 121A, and the axle hub 120 is rotatable with respect to the cylindrical support portion 111, that is, the knuckle. The pair of annular seal members 114 and 115 are arranged at a predetermined distance in the axial direction of the rotating shaft portion 121A, and are cylindrically supported so as to sandwich the cylinder member 150 and both bearings 112 and 113 in the axial direction of the rotating shaft portion 121A. It is interposed between the part 111 and the rotating shaft part 121A, and seals between the cylindrical support part 111 and the rotating shaft part 121A in a liquid-tight manner.

  The axle hub 120 includes a hub main body 121 and a sleeve 122 that is liquid-tightly screwed to the outer periphery of the lower end portion of the hub main body 121. The hub body 121 includes a rotating shaft portion 121A and an annular flange portion 121B. The rotating shaft portion 121A is formed with an axial groove 121a, a suction passage 121b, and a discharge passage 121c, and the annular flange portion 121B includes a wheel. A mounting portion 121d (not shown) (not shown in detail) is formed.

  The axial groove 121 a is guide means for guiding the protrusion 130 a formed on the inner periphery of the piston 130 in the axial direction, and is formed on the outer periphery of the rotating shaft portion 121 </ b> A in the axle hub 120. The suction passage 121b is for introducing (suctioning) air into a pump chamber Ro formed between the piston 130 and the cylinder member 150, and a suction check valve Vi is interposed therein. The discharge passage 121c is used to lead out (discharge) air from the pump chamber Ro, and a discharge check valve Vo is interposed therein. The pressurized air discharged from the pump chamber Ro can be supplied to a tire air chamber (not shown) of a wheel assembled to the axle hub 120.

  The piston 130 is accommodated in the cylinder member 150 outside the rotating shaft portion 21A of the axle hub 20, has the above-described protrusion 130a, and extends in the piston radial direction to attach the cam follower 142, the spring 143, and the holder 144. Mounting hole 130b. The piston 130 is fitted to the axial groove 121a of the rotary shaft portion 21A at the protrusion 130a so as to be integrally rotatable and reciprocally movable in the axial direction, and is coaxial with the rotary shaft portion 21A of the axle hub 20. It is assembled so that it can rotate integrally and reciprocate in the axial direction.

  In addition, the piston 130 is fitted to the rotating shaft portion 21A of the axle hub 20 via a pair of annular seal members 131 and 132 on the inner periphery, and a pair of cylinders 150 in the cylinder inner hole 150a on the outer periphery. The pump chamber Ro is inserted in the cylinder member 150 on the outer periphery of the rotating shaft portion 121A, and the atmospheric chamber Ra is formed through the annular seal members 133 and 134. Note that the atmosphere chamber Ra communicates with the atmosphere through a communication passage 121e formed in the rotating shaft 121A and the portion on the atmosphere side from the suction check valve Vi of the suction passage 121b described above.

  The pair of annular seal members 131 and 132 are disposed a predetermined distance apart in the axial direction of the rotating shaft 121A, and are interposed between the piston 130 and the rotating shaft 121A at the axial end of the piston 130. The piston 130 and the rotary shaft 121A are hermetically and liquid-tightly sealed. The pair of annular seal members 133 and 134 are disposed a predetermined amount apart in the axial direction of the rotating shaft portion 121A, and are interposed between the piston 130 and the cylinder member 150 at the axial end portion of the piston 130, The piston 130 and the cylinder member 150 are hermetically and liquid-tightly sealed.

  The cylinder member 150 is formed in a cylindrical shape, and is fitted to the outer periphery of the rotation shaft portion 121A of the axle hub 120 via a pair of annular seal members 151 and 152 in the cylindrical support portion 111. 111 and the rotating shaft 121A of the axle hub 120. The cylinder member 150 is coaxially arranged with respect to the rotating shaft portion 121A, and is provided integrally with the cylindrical support portion 111 (cannot move in the axial direction and cannot rotate). Is provided with a cylinder inner hole 150a for reciprocating movement in the axial direction of the rotary shaft portion 121A, and an annular groove 150b on the outer periphery.

  The annular groove 150 b forms an annular space R 11 between the cylindrical support portion 111 and the cylinder member 150. The annular space R11 communicates with an annular space R12 formed between the pair of annular seal members 114 and 151 through a communication hole 150c formed in the cylinder member 150, and passes through a communication hole 150d formed in the cylinder member 150. It communicates with an annular space R13 formed between the annular seal members 115, 152. Each of the annular spaces R11, R12, and R13 is an oil chamber that stores a required amount of lubricating oil. The lubricating oil stored in the oil chamber is transferred to the bearings 112 and 113 and the annular seal members 114, 115, 151, and 152. In addition to being supplied, it is also supplied to the engaging portion of the cylindrical cam 141 and the cam follower 142, the sliding portion of the piston 130, and the like through a communication hole 150e formed in the cylinder member 150.

  The cylindrical cam 141 is integrally formed on the inner periphery of the cylinder member 150 and is coaxially disposed with respect to the rotating shaft portion 121A. Further, the cylindrical cam 141 has a cam groove 141a that is annular and varies in the axial direction of the rotary shaft 121A, and the cam follower 142 is fitted therein. The cam groove 141a has a cam surface that receives an axial load (a vertical load in the drawing) and a radial load (a horizontal load in the drawing) from the cam follower 142, and the cam surface has a V-shaped cross section. It is a shape and is formed with an even number of cycles (for example, two cycles) in the circumferential direction of the rotating shaft 121A.

  The cam follower 142 is a ball that is rotatably attached to a holder 144 that is attached to the mounting hole 130b of the piston 130, and is urged outward of the piston diameter by a spring 143 to engage with the cam groove 141a. The spring 143 is interposed between the cam follower 142 and the holder 144, and urges the cam follower 142 toward the outside of the piston diameter. The holder 144 is formed in a bottomed cylindrical shape, and is provided in the mounting hole 130b of the piston 130 so as to be movable in the piston radial direction.

  In the pressure generating device AP2 of the second embodiment configured as described above, when the axle hub 120 rotates with respect to the cylindrical support portion 111, the piston 130 and the cam follower 142 rotate integrally with the axle hub 120, and the cylindrical cam. It rotates relative to 141 and moves in the axial direction. For this reason, the rotational movement of the axle hub 120 can be converted into the reciprocating motion of the piston 130, and the volume of the pump chamber Ro can be increased or decreased by the reciprocating motion of the piston 130, and the suction check valve Vi is interposed. Air can be sucked into the pump chamber Ro through the suction passage 121b, and air can be discharged from the pump chamber Ro through the discharge passage 121c provided with the discharge check valve Vo. This discharge air (pressurized air) is used as the axle hub. It can be supplied to a tire air chamber (not shown) of a wheel assembled to 120.

  By the way, in the pressure generating device AP2 of the second embodiment, the rotating shaft part 121A of the axle hub 120 is rotatably supported in the cylindrical support part 111 via bearings 112 and 113, and the axle hub 120 rotates. The piston 130 is coaxial with the shaft portion 121A, can be integrally rotated, and can be reciprocated in the axial direction (pump operation is possible) to form a pump chamber Ro that is exposed to the rotating shaft portion 121A. Therefore, it is not necessary to provide a balance weight in the axle hub 120 in order to balance the rotational balance, and the pressure generating device AP2 can be configured compactly in the cylindrical support portion 111. Thus, the pressure generating device AP2 can be downsized.

  Further, in the pressure generating device AP2 of the second embodiment, the rotating shaft 121A of the axle hub 120 is cylindrical through a pair of bearings 112 and 113 arranged at predetermined intervals in the axial direction of the rotating shaft 121A. The support portion 111 is rotatably supported. For this reason, it is possible to ensure the support rigidity of the axle hub 120 with respect to the cylindrical support part 111 by the pair of bearings 112 and 113. Further, a cylindrical cam 141 and a cam follower 142 as a motion conversion mechanism are interposed between the pair of bearings 112 and 113. For this reason, the space between the pair of bearings 112 and 113 can be effectively utilized as a space for accommodating the motion conversion mechanism, and the pressure generating device AP2 can be configured compactly.

  Further, in the pressure generating device AP2 of the second embodiment, the cylinder member 150 and the two bearings 112 and 113 are disposed between the rotation shaft portion 121A of the axle hub 120 and the cylindrical support portion 111 in the axial direction of the rotation shaft portion 121A. A pair of annular seal members 114 and 115 for sealing the pair of bearings 112 and 113 so as to be sandwiched are interposed. Therefore, the pair of bearings 112 and 113 can be sealed by the pair of annular seal members 114 and 115, and the cylindrical cam 141 and the cam follower 142 as the motion conversion mechanism can be sealed. The pressure generating device AP2 can be made compact and low in cost by sharing the members.

  Further, in the pressure generating device AP2 of the second embodiment, an oil chamber (annular spaces R12, R13) that is sealed by the annular seal members 114, 115, 131 to 134, 151, 152 and accommodates a required amount of hydraulic oil. ) And the lubricating oil can be supplied from the oil chamber (annular space R11) to the engaging portion of the cylindrical cam 141 and the cam follower 142 and the sliding portion of the piston 130 through the communication hole 150e. . For this reason, the lubricity of each sliding part is ensured, and it is possible to reduce sliding resistance and improve durability at each sliding part.

  In the pressure generating device AP2 of the second embodiment described above, the rotational movement of the axle hub 120 with respect to the cylindrical support portion 111 is performed by the cam follower 142 provided on the outer periphery of the piston 130 and the cylindrical cam 141 provided on the inner periphery of the cylinder member 150. Is converted into a reciprocating motion of the piston 130, but a cylindrical cam 141 provided on the outer periphery of the piston 130, as in the modified embodiment shown in FIG. The cam follower 142 provided on the inner periphery of the cylinder member 150 constitutes and implements a motion conversion mechanism (external cam motion conversion mechanism) that converts the rotational motion of the axle hub 120 relative to the cylindrical support portion 111 into the reciprocating motion of the piston 130. It is also possible.

  Further, in the pressure generating device AP2 of the second embodiment described above, the protrusion 130a is provided on the inner periphery of the piston 130, and the axial groove 121a is provided on the outer periphery of the rotating shaft portion 121A, so that the protrusion 130a (piston 130) is provided. Although it is configured to be fitted to the axial groove 121a (rotating shaft portion 121A) so as to be integrally rotatable and reciprocally movable in the axial direction, the piston 130 of the piston 130 is modified as in the modified embodiment shown in FIG. An axial groove 130c is provided on the inner periphery, and a protrusion 121f is provided on the outer periphery of the rotating shaft portion 121A. The axial groove 130c (piston 130) can rotate integrally with the protrusion 121f (rotating shaft portion 121A) and axially. It is also possible to configure and implement so that it can be reciprocated.

  4 and 5 show a third embodiment of the pressure generating device according to the present invention, and the pressure generating device AP3 of the third embodiment supplies pressurized air to a tire air chamber (not shown) of a wheel in a vehicle. A pneumatic pressure generating device that can be supplied, and includes a cylindrical support portion 211 that is a part of a knuckle as a support member, an axle hub 220 as a rotating body, and two pistons 230 as a pump operating body, and an axle hub A cam member 241 and two cam followers 242 are provided as a motion conversion mechanism for converting the rotational motion of 220 with respect to the cylindrical support portion 211 into the reciprocating motion of each piston 230.

  The cylindrical support portion 211 is formed in a cylindrical shape with the axis line Lo as the center and cannot rotate around the axis line Lo. Inside the rotation axis part 221A of the axle hub 220, a pair of bearings 212 and 213 and a pair are provided. Are rotatably supported around the axis Lo and liquid-tightly through the annular seal members 214 and 215. The pair of bearings 212 and 213 are arranged a predetermined distance apart in the axial direction (direction along the axis line Lo) of the rotating shaft portion 221A, and are cylindrically supported so as to sandwich the cam member 241 in the axial direction of the rotating shaft portion 221A. The shaft hub 220 is interposed between the portion 211 and the rotating shaft portion 221A, and the axle hub 220 is rotatable with respect to the cylindrical support portion 211, that is, the knuckle. The pair of annular seal members 214 and 215 are disposed at a predetermined distance in the axial direction of the rotary shaft portion 221A, and are cylindrically supported so as to sandwich the cam member 241 and both bearings 212 and 213 in the axial direction of the rotary shaft portion 221A. It is interposed between the part 211 and the rotating shaft part 221A, and seals between the cylindrical support part 211 and the rotating shaft part 221A in a liquid-tight manner.

  The axle hub 220 includes a hub body 221 and a sleeve 222 that is liquid-tightly screwed to the outer periphery of the lower end portion of the hub body 221. The hub body 221 includes a rotating shaft portion 221A and an annular flange portion 221B. The rotating shaft portion 221A has a pair of two cylinder inner holes 221a, and the annular flange portion 221B has a wheel (not shown). Mounting portion 221b (details omitted) are formed, and a suction passage 221c and a discharge passage 221d are formed in the rotating shaft portion 221A and the annular flange portion 221B.

  The cylinder inner holes 221a are formed in the radial direction of the rotary shaft portion 221A at intervals of 180 degrees in the circumferential direction of the rotary shaft portion 221A in the axle hub 220, and the piston 230 is formed in the radial direction of the rotary shaft portion 221A. The pump chamber Ro is formed in the rotating shaft portion 221 </ b> A by the piston 230. Each pump chamber Ro communicates with each other through a communication hole 221e provided in the rotating shaft portion 221A.

  The intake passage 221c is for introducing (inhaling) air into the pump chamber Ro, and an intake check valve Vi is interposed therein. The discharge passage 221d is for leading out (discharge) air from the pump chamber Ro, and a discharge check valve Vo is interposed therein. The pressurized air discharged from the pump chamber Ro can be supplied to a wheel tire air chamber (not shown) assembled to the axle hub 220.

  Each piston 230 is formed in a columnar shape, and is inserted into a cylinder inner hole 221a of the rotation shaft portion 221A of the axle hub 220 via an annular seal member 231. The piston 230 is connected to the rotation shaft portion 221A of the axle hub 220. It is assembled so that it can rotate integrally and reciprocate in the cylinder axis direction. In addition, each piston 230 is formed with a recess 230 a that accommodates a part of the compression coil spring 243. Each annular seal member 231 is assembled in an annular groove formed on the outer periphery of each piston 230, and seals between the piston 230 and the rotary shaft portion 221A in an airtight and liquid tight manner.

  The cam member 241 is a cylindrical cam provided integrally with the cylindrical support portion 211 (not movable in the axial direction and not rotatable), and is disposed coaxially with the rotary shaft portion 221A. Further, the cam member 241 has an elliptical cam surface 241a on the inner periphery, and each cam follower 242 is engaged with the cam surface 241a. The cam surface 241a can reciprocate each cam follower 242 and each piston 230 twice in the piston axis direction while the rotation shaft portion 221A makes one rotation with respect to the cylindrical support portion 211.

  Each cam follower 242 is a ball that is rotatably assembled to an outer end portion 230b that protrudes outward from the cylinder inner hole 211a of the piston 230, and can roll on the cam surface 241a of the cam member 241 at the outer end portion. It is engaged and can move in the piston axial direction together with the piston 230 by rotating relative to the cam member 241. In addition, the annular space R21 that accommodates each cam follower 242 and the like is sealed by each seal member 214, 215, 231, 231, and the inside includes bearings 212, 213, a cam member 241, each cam follower 242, each piston 230, and the like. A required amount of lubricating oil for lubricating the oil is contained.

  Further, in the third embodiment, an air chamber R22 (see FIG. 5) as a volume change amount reducing means for reducing the volume change amount of the annular space R21 due to the reciprocating movement of both pistons 230 is provided to face. Yes. Each air chamber R22 decreases in volume as the volume of the annular space R21 decreases, and increases in volume as the volume of the annular space R21 increases. The air chamber R22 is assembled to the outer periphery of the rotary shaft portion 221A so as to be integrally rotatable. It is formed by the attached air bag 250. Each air bag 250 is made of a material having elasticity and airtightness such as rubber, and is filled with compressed air. As the volume of the annular space R21 decreases and the internal pressure increases. It contracts and expands as the volume of the annular space R21 increases and the internal pressure decreases. For this reason, it is possible to reduce the pressure increase / decrease in the annular space R21 during operation, and to reduce the pump loss associated therewith.

  In the pressure generating device AP3 of the third embodiment configured as described above, when the axle hub 220 rotates with respect to the cylindrical support portion 211, each piston 230 and each cam follower 242 rotate integrally with the axle hub 220. It rotates relative to the cam member 241 and moves in the piston axial direction. Therefore, the rotational motion of the axle hub 220 can be converted into the reciprocating motion of each piston 230, and the volume of the pump chamber Ro can be increased or decreased by the reciprocating motion of each piston 230, and the suction check valve Vi is interposed. It is possible to suck air into each pump chamber Ro through the mounted suction passage 211c and the communication hole 221e, and discharge air from each pump chamber Ro through the discharge passage 211d provided with the communication hole 221e and the discharge check valve Vo. The discharged air (pressurized air) can be supplied to a tire air chamber (not shown) of a wheel assembled to the axle hub 220.

  By the way, in the pressure generating device AP3 of the third embodiment, the rotation shaft portion 221A of the axle hub 220 is rotatably supported in the cylindrical support portion 211 via bearings 212 and 213, and the rotation of the axle hub 220 is performed. Each piston 230 is assembled to the shaft portion 221A so as to be able to rotate integrally and reciprocate in the axial direction (pump operation is possible) to form a pump chamber Ro exposed to the rotation shaft portion 221A. Therefore, it is not necessary to provide a balance weight in the axle hub 220 in order to balance the rotational balance, and the pressure generating device AP3 can be configured compactly in the cylindrical support portion 211. Thus, the pressure generating device AP3 can be downsized.

  Further, in the pressure generating device AP3 of the third embodiment, the rotating shaft portion 221A of the axle hub 220 is cylindrical through a pair of bearings 212 and 213 arranged at predetermined intervals in the axial direction of the rotating shaft portion 221A. The support part 211 is rotatably supported. For this reason, it is possible to ensure the support rigidity of the axle hub 220 with respect to the cylindrical support part 211 by the pair of bearings 212 and 213. Further, a cam member 241 and a cam follower 242 as a motion conversion mechanism are interposed between the pair of bearings 212 and 213. For this reason, the space between the pair of bearings 212 and 213 can be effectively utilized as the accommodation space of the motion conversion mechanism, and the pressure generating device AP3 can be configured compactly.

  Further, in the pressure generating device AP3 of the third embodiment, the cam member 241 and the two bearings 212 and 213 are disposed between the rotation shaft portion 221A of the axle hub 220 and the cylindrical support portion 211 in the axial direction of the rotation shaft portion 221A. A pair of annular seal members 214 and 215 that seal the pair of bearings 212 and 213 so as to be sandwiched are interposed. For this reason, the pair of bearings 212 and 213 can be sealed by the pair of annular seal members 214 and 215, and the cam member 241 and the cam follower 242 as a motion conversion mechanism can be sealed. The pressure generating device AP3 can be made compact and low in cost by sharing the members.

  Further, in the pressure generating device AP3 of the third embodiment, an annular seal member 231 that provides a fluid-tight seal between each piston 230 and the rotating shaft portion 221A of the axle hub 220 is provided, and the rotating shaft of the axle hub 220 is also provided. Annular seal members 214 and 215 that liquid-tightly seal between the portion 221A and the cylindrical support portion 211 are arranged apart from each other by a predetermined amount in the axial direction, and are sealed by these seal members 214, 215, 231, and 231 and required Bearings 212 and 213, cam members 241, cam followers 242, pistons 230, and the like are housed in the annular space R <b> 21 that accommodates an amount of hydraulic oil. For this reason, the lubricity of each sliding part is ensured, and it is possible to reduce sliding resistance and improve durability at each sliding part.

1 is a cross-sectional view schematically illustrating a first embodiment of a pressure generating device according to the present invention. It is sectional drawing which showed schematically 2nd Embodiment of the pressure production | generation apparatus by this invention. FIG. 3 is a partial cross-sectional view schematically showing a modified embodiment of the second embodiment shown in FIG. 2. It is sectional drawing which showed schematically 3rd Embodiment of the pressure generation apparatus by this invention. FIG. 5 is a cross-sectional view taken along line 5-5 of the third embodiment shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Cylindrical support part, 12, 13 ... Bearing, 14, 15 ... Ring seal member, 20 ... Axle hub (rotary body), 21A ... Rotary shaft part, 21b ... Cylinder inner hole, 21d ... Suction passage, 21e ... Discharge passage , 30 ... piston (pump operating body), 41 ... cam member, 42 ... cam follower, 43 ... rod (load transmitter), Vi ... suction valve, Vo ... discharge valve, Ro ... pump chamber, AP1 ... pressure generator

Claims (9)

  A rotating body provided with a rotating shaft portion rotatably supported via a bearing in a non-rotatable support member, and assembled to the rotating shaft portion of the rotating body so as to be integrally rotatable and capable of operating a pump. A pump operating body that forms a pump chamber, a motion conversion mechanism that converts a rotational motion of the rotating body relative to the support member into a pump operation of the pump operating body, and is formed in the rotating body so that fluid can be sucked into the pump chamber. A pressure generation device comprising a suction passage and a discharge passage formed in the rotating body and capable of discharging fluid from the pump chamber.   The pressure generating device according to claim 1, wherein the rotating body is an axle hub of a vehicle, the support member is a knuckle that rotatably supports the axle hub, and the fluid is air. Pressure generator.   3. The pressure generating device according to claim 1, wherein the pump operating body is a piston assembled so as to be integrally rotatable and reciprocating with respect to the rotating shaft portion, and the motion conversion mechanism is the piston of the rotating body. A pressure generating device, wherein the pressure generating device is a motion converting mechanism that converts a rotational motion with respect to a support member into a reciprocating motion of the piston.   4. The pressure generating device according to claim 3, wherein a cylinder inner hole that accommodates the piston so as to be capable of reciprocating in the axial direction of the rotary shaft portion is coaxially formed in the rotary shaft portion. A load transmission element that penetrates the rotation shaft portion in the axial direction and cannot move in the rotation direction is provided, and a cam follower provided at an outer end in the piston radial direction of the load transmission element and the support member The pressure generating device is characterized in that the motion conversion mechanism is constituted by a cylindrical cam assembled to the cylinder.   The pressure generating device according to claim 3, wherein the piston is formed in a cylindrical shape and is assembled to the outer periphery of the rotating shaft portion so as to be integrally rotatable and reciprocally movable in an axial direction, A cylinder member that is provided integrally with the support member and accommodates the piston so as to reciprocate in the axial direction is interposed between the rotating shaft portions, and the motion conversion is performed between the piston and the cylinder member. A pressure generating device, wherein a mechanism is set.   4. The pressure generating device according to claim 3, wherein the rotating shaft portion is formed with a cylinder inner hole for reciprocally moving the piston in a radial direction of the rotating shaft portion, and the cylinder of the piston. The pressure generating device is characterized in that the motion conversion mechanism is constituted by a cam follower provided at an outer end protruding outward from an inner hole and a cylindrical cam assembled in the support member.   The pressure generating device according to any one of claims 1 to 6, wherein the rotary shaft portion is rotatable to the support member via a first bearing and a second bearing arranged at predetermined intervals in the axial direction. It is supported by the pressure generating device.   8. The pressure generating device according to claim 7, wherein the motion conversion mechanism is interposed between the first bearing and the second bearing. 9. The pressure generating device according to claim 8, wherein a first seal member and a second seal member for sealing the first bearing and the second bearing are moved between the rotating shaft portion and the support member. A pressure generating device, wherein the mechanism and the both bearings are interposed in the axial direction.

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