JP2016107902A - Free wheel hub - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably maintain a two-wheel drive state, and to enhance the reliability of power transmission, in a free wheel hub which maintains the two-wheel drive state by magnetically sucking an outside reinforcing plate by a magnet.SOLUTION: An external peripheral face of a diaphragm 13 is gripped by a sleeve 8 and a diaphragm cover 14, and a two-wheel drive side negative pressure chamber 21 and a four-wheel drive side negative pressure chamber 22 are arranged in a hub housing 6. A slide gear 11 arranged at an axial end of an axle 1 is connected to the diaphragm, and engaged with and released from an outer gear 7 which integrally rotates together with the hub housing. A magnet 30 is attached to an internal face of the diaphragm cover, an outside reinforcing plate 15 arranged outside the diaphragm is sucked, and a switching state to two-wheel drive for the engagement and release is maintained. A stopper pin is inserted into a radial hole which is formed at the axial end of the axle 1, a slide mechanism 34 is operated in cooperation with the diaphragm, the stopper pin is moved to the outside of a radial direction, and the movement of the slide gear is prohibited.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a freewheel hub for a four-wheel drive vehicle.

  The FR-based four-wheel drive vehicle has a transfer that distributes the power from the engine and the transmission to the front propeller shaft and the rear propeller shaft, and the two-wheel drive (2WD) and four-wheel drive (4WD) are transferred by the transfer. Switching is performed.

  Here, when the driven side wheel and the driven side axle are in a coupled state during traveling by two-wheel drive, the driven side axle is rotated from the driven side wheel, so that the traveling resistance increases and energy is wasted. Will be consumed.

  In order to eliminate such inconvenience, in the four-wheel drive vehicle described in Patent Document 1, a free wheel hub is provided between the driven wheel and the driven axle, and the transfer is switched to the two-wheel drive. The driven wheel is separated from the driven axle, and the driven wheel is set in a free state so as to reduce useless running resistance. On the other hand, when the transfer is switched to four-wheel drive, the driven wheel and the driven axle are locked, and the power from the engine is transmitted to the driven wheel.

  In order to switch between two-wheel drive and four-wheel drive, in the free wheel hub described in Patent Document 1, the wheel hub of the driven wheel is provided rotatably on the same axis as the driven axle. A two-wheel drive side negative pressure chamber and a four-wheel drive side negative pressure chamber are formed by incorporating a diaphragm into a hub housing connected to the side end face. Deform toward the wheel drive side negative pressure chamber, slide the slide gear connected to the diaphragm on the driven side axle, release the mesh with the outer gear fixed inside the hub housing, and move it to the driven side axle On the other hand, the wheel hub is in a free state.

  Further, the diaphragm is deformed toward the four-wheel drive side negative pressure chamber by depressurization of the four-wheel drive side negative pressure chamber, and a slide gear that moves toward the outer gear side is engaged with the outer gear so that the wheel hub is engaged with the driven side axle. Is locked.

  Here, in order to maintain the two-wheel drive state (free state) or the four-wheel drive state (lock state), the pressure reduction of the two-wheel drive side negative pressure chamber or the four-wheel drive side negative pressure chamber is maintained for a long time. If so, a large suction force is always applied to the sealing member that seals each of the negative pressure chambers and the sealing seal member of the suction path that communicates with each negative pressure chamber, and the function of the sealing member is reduced, Durability will be reduced.

  In order to eliminate such inconvenience, in the above free wheel hub, a magnet is attached to the inner surface of the diaphragm cover that holds the outer periphery of the diaphragm, and the magnet adsorbs an outer reinforcing plate provided outside the diaphragm. The two-wheel drive state is maintained.

  Also, a spring is incorporated between the diaphragm cover and the outer reinforcing plate, and the four-wheel drive state is maintained by the action of the spring pressing the diaphragm toward the four-wheel drive side negative pressure chamber. At this time, since the two-wheel drive state cannot be maintained if the magnetic attractive force by the magnet is smaller than the elastic force of the spring, the magnetic attractive force by the magnet is set to a value higher than the pressing force of the spring.

Japanese Patent Laid-Open No. 10-278621

  Incidentally, as described above, in a freewheel hub that maintains a two-wheel drive state by magnetically attracting the outer reinforcing plate as described above, when a large vibration is applied in the traveling state in the two-wheel drive state, the magnet There is a possibility that the two-wheel drive state cannot be maintained because the adsorption of the outer reinforcing plate due to is released.

  An object of the present invention is to stabilize the maintenance of a two-wheel drive state and improve the reliability of power transmission in a freewheel hub that magnetically attracts an outer reinforcing plate with a magnet to maintain the two-wheel drive state. .

  In order to solve the above-described problems, in the present invention, a wheel hub of a driven wheel is provided rotatably on the same axis as the driven axle, and is connected to an outer side end surface of the wheel hub so as to be connected to the shaft end of the driven axle. An outer gear that rotates integrally with the hub housing is provided inside the hub housing that covers the portion, and a slide gear that can mesh with the outer gear is slidably provided at the end of the driven axle, and the outer side of the outer gear The outer peripheral portion of the diaphragm is sandwiched from both sides by the end face of the sleeve provided on the outer periphery of the sleeve and the outer peripheral portion of the diaphragm cover connected to the outer end portion of the sleeve, and the two-wheel drive side negative is placed on the outer side in the axial direction of the diaphragm. A pressure chamber and a four-wheel drive side negative pressure chamber are provided on the inner side in the axial direction, and the inner peripheral portion of the diaphragm is sandwiched between the outer reinforcing plate and the inner reinforcing plate from both sides. A reinforcing plate is connected to the slide gear, and the slide cover is moved to a direction in which the meshing with the outer gear is released by elastic deformation of the diaphragm due to the pressure reduction of the two-wheel drive side negative pressure chamber to switch to the two-wheel drive, and the diaphragm cover A position where the magnet attached to the inner surface of the motor is switched to the two-wheel drive by the action of magnetically attracting the outer reinforcing plate, and the slide gear meshes with the outer gear by the elastic deformation of the diaphragm due to the decompression of the negative pressure chamber on the four-wheel drive side. In the freewheel hub, the driven side axle is configured to maintain the switching state to the four-wheel drive by a spring that biases the diaphragm toward the four-wheel drive chamber side negative pressure chamber. A shaft hole that opens at the shaft end surface and a radial hole that penetrates from the outer diameter surface to the shaft hole are provided. A stopper pin that is axially opposed to the inner side end face of the slide gear when protruding, and is interlocked with the elastic deformation toward the two-wheel drive side negative pressure chamber of the diaphragm. A configuration is adopted in which a slide mechanism is provided that moves the lens toward the outside in the radial direction.

  In the free wheel hub configured as described above, the diaphragm is elastically deformed toward the two-wheel drive side negative pressure chamber by reducing the pressure on the two-wheel drive side negative pressure chamber, and the slide gear is moved in a direction to release the engagement with the outer gear. When switched to two-wheel drive, the outer reinforcing plate is attracted by the magnet and held in the two-wheel drive state. The stopper pin protrudes outward from the outer diameter surface of the driven-side axle and faces the inner side end surface of the slide gear in the axial direction.

  For this reason, even if the suction of the outer reinforcing plate by the magnet is released due to a load such as abnormal vibration, the stopper pin prevents the slide gear from moving in the direction of meshing with the outer gear, and the two-wheel drive state Is maintained.

  Here, as a slide mechanism for moving the stopper pin radially outward, a slide shaft that slides in the shaft hole in conjunction with the elastic deformation of the diaphragm is provided, and the outer side end of the slide shaft is defined as a small-diameter end. And a stopper pin is urged radially inward by an elastic member so that its inner end is brought into elastic contact with the taper surface, and the cam of the taper surface is moved by moving the slide shaft in the axial direction. It is possible to adopt a configuration in which the stopper pin is slid by action.

  The slide shaft may be connected to the inner and outer reinforcing plates that reinforce the inner peripheral portion of the diaphragm, or may be separated from the reinforcing plate. When the slide shaft is separated from the reinforcing plate, an elastic member is incorporated in the shaft hole, and the slide shaft is urged toward the diaphragm.

  If the slide shaft is connected to the reinforcing plate, the elastic member is not required, and the number of parts can be reduced and the assembly can be facilitated. For connecting the slide shaft to the reinforcing plate, a method of caulking, screwing, or adhering the shaft end portion of the slide shaft penetrating through the central portion of the outer reinforcing plate can be employed.

  In the freewheel hub according to the present invention, as described above, the stopper pin protrudes from the outer diameter surface of the driven-side axle when switching to the two-wheel drive state in which the slide gear is disengaged from the outer gear. Therefore, the stopper pin can prevent the slide gear from moving in the direction of meshing with the outer gear even if the outer reinforcement plate is attracted to the magnet by a load such as abnormal vibration. . As a result, the two-wheel drive state can be reliably maintained, and the reliability of power transmission can be improved.

A longitudinal sectional view showing an embodiment of a freewheel hub according to the present invention Sectional drawing which expands and shows a part of FIG. Sectional view showing the four-wheel drive state of the freewheel hub Sectional drawing which shows the other example of a slide mechanism

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, a front axle 1 as a driven side axle and a wheel hub 2 of a front wheel as a driven wheel provided on the outside thereof are arranged coaxially.

  A cylindrical spindle 3 is incorporated between the front axle 1 and the wheel hub 2, and the spindle 3 and the wheel hub 2 are relatively rotatably supported by a bearing 4.

  A hub housing 6 is connected to the outer end surface of the wheel hub 2 by tightening bolts 5 that are screwed into the wheel hub 2. An outer gear 7 is incorporated in the hub housing 6 and a sleeve 8 is incorporated on the outer side in the axial direction.

  The outer gear 7 has a ring shape, and spline teeth 9 as tooth portions are formed on the inner periphery thereof. Each of the outer gear 7 and the sleeve 8 is fixed to the inner diameter surface of the hub housing 6 by fitting with a spline, and rotates integrally with the hub housing 6. The outer gear 7 and the sleeve 8 are arranged in the axial direction. The opposing surfaces are sealed by incorporating a seal member 10.

  A slide gear 11 is fitted to the shaft end located inside the hub housing 6 of the front axle 1. The slide gear 11 is prevented from rotating on the front axle 1 by fitting a spline or serration, and is supported so as to be movable in the axial direction, and has a spline tooth 12 that can mesh with the spline teeth 9 of the outer gear 7 on its outer diameter surface. Is provided.

  A diaphragm 13 is incorporated in the hub housing 6 outside the sleeve 8 in the axial direction. The outer peripheral portion of the diaphragm 13 is sandwiched from both sides by an outer end surface of the sleeve 8 and a diaphragm cover 14 having a cylindrical portion 14a that is press-fitted into the outer periphery of the outer end portion of the sleeve 8 on the outer periphery.

  The central portion of the diaphragm 13 is sandwiched between the outer reinforcing plate 15 and the inner reinforcing plate 16 from both sides, and the outer reinforcing plate 15 and the inner reinforcing plate 16 are coupled and integrated by caulking a rivet 17 inserted through the center hole. ing.

  The outer reinforcing plate 15 and the inner reinforcing plate 16 are made of a press-formed product of a magnetic metal plate. A cylindrical portion 18 is provided on the outer peripheral portion of the inner reinforcing plate 16, and the opening end of the cylindrical portion 18 is bent inward. Thus, an inner cylinder portion 18a is formed, and the inner cylinder portion 18a is fitted to a cylindrical outer diameter surface 11a formed on the outer periphery of the outer side end portion of the slide gear 11, and is connected to the slide gear 11 in the axial direction. Has been.

  When the inner reinforcing plate 16 and the slide gear 11 are connected in the axial direction, here, a ring groove 19 is formed at the end of the cylindrical outer diameter surface 11 a of the slide gear 11, and a retaining ring 20 fitted in the ring groove 19. The end portion of the inner cylinder portion 18a is engaged.

  By incorporating the diaphragm 13, a two-wheel drive side negative pressure chamber 21 is formed inside the hub housing 6 in the axial direction outside of the diaphragm 13, and a four-wheel drive side negative pressure chamber 22 is formed in the axial direction inside of the diaphragm 13. Has been.

  A ring member 23 is fitted to the outer side end portion of the spindle 3, and the cylindrical portion 23 a provided at the outer side end portion of the ring member 23 and the opening end portion of the hub housing 6 are opposed to each other in the radial direction. The parts are sealed by incorporating a seal member 24.

  A flange 3a is provided at the inner end of the spindle 3 so as to face the inner end of the wheel hub 2 in the axial direction. The flange 3a and the opposite portion of the wheel hub 2 are hermetically sealed by incorporating a pair of seal members 25. ing. Further, the radial facing portions of the front axle 1 and the flange 3 a are also sealed by incorporating the seal member 26.

The flange 3a of the spindle 3, the first port _{P 1} and the second port _{P 2} is provided. The first port P ₁ communicates with the two-wheel drive-side negative pressure chamber 21 via a first suction path 27 formed between the inner periphery of the wheel hub 2 and the outer periphery of the spindle 3 and on the inner diameter surface of the hub housing 6. two-wheel drive-side negative pressure chamber 21 is depressurized by sucking the first port P _1.

Meanwhile, the second port P ₂ communicates via the second suction passage 28 provided between the inner periphery of the outer peripheral and the spindle 3 of the front axle 1, the four-wheel drive side by sucking the second port P ₂ The negative pressure chamber 22 is depressurized.

  As shown in FIG. 2, a spring 29 and a magnet 30 are incorporated inside the diaphragm cover 14. The spring 29 urges the slide gear 11 toward the outer gear 7 via the diaphragm 13 and holds the slide gear 11 in a state of meshing with the outer gear 7.

  On the other hand, when the magnet 30 is fixed to the inner surface of the end plate of the diaphragm cover 14 and the diaphragm 13 is deformed toward the negative pressure chamber 21 on the two-wheel drive side, the slide gear 11 is disengaged from the outer gear 7. The outer reinforcing plate 15 is magnetically attracted to hold the slide gear 11 in the disengaged state.

  The front axle 1 is formed with a shaft hole 31 that opens at the shaft end surface, and a radial hole 32 that penetrates the shaft hole 31 from the outer diameter surface. The radial hole 32 is provided at a position where the slide gear 11 is disengaged from the outer gear 7, at a position disposed on the inner side from the inner side end face of the slide gear 11, and a stopper pin is provided in the radial hole 32. 33 is slidably inserted.

  Between the diaphragm 13 and the stopper pin 33, there is a slide mechanism 34 that moves the stopper pin 33 radially outward in conjunction with the elastic deformation of the diaphragm 13 toward the two-wheel drive negative pressure chamber 21. Is provided.

  The slide mechanism 34 incorporates a slide shaft 35 in the shaft hole 31 of the front axle 1 and an elastic member 36 that urges the slide shaft 35 toward the diaphragm 13 to abut the outer side end surface against the rivet 17. The slide shaft 35 is provided with a tapered surface 37 whose outer side end is a small-diameter end, the stopper pin 33 is urged radially inward by an elastic member 38, and the inner end thereof is directed to the tapered surface 37. Elastic contact is made.

  The freewheel hub shown in the embodiment has the above-described structure. FIGS. 1 and 2 show a traveling state by two-wheel drive, and as shown in FIG. 2, the diaphragm 13 is placed in the two-wheel drive side negative pressure chamber 21. The slide gear 11 is in a state of being released from meshing with the outer gear 7.

  The stopper pin 33 has an inner end guided by a tapered surface 37 of the slide shaft 35 and an outer end projecting outward from the outer diameter surface of the front axle 1 so as to face the inner end surface of the slide gear 11 in the axial direction. doing.

In the running state by the two-wheel drive shown in FIGS. 1 and 2, when applying a suction force to the second port P _2, four-wheel drive-side negative pressure chamber 22 is depressurized, the diaphragm 13 is 4-wheel drive-side negative pressure chamber 22 Elastically deforms toward

  Due to the elastic deformation of the diaphragm 13 toward the four-wheel drive side negative pressure chamber 22, the slide shaft 35 is pushed into the shaft hole 31 against the elasticity of the elastic member 36, and is connected to the small diameter end of the tapered surface 37. The outer diameter surface of the small-diameter shaft portion 35 a faces the stopper pin 33, and the stopper pin 33 moves inward in the radial direction by the pressing of the elastic member 38 and is immersed in the radial hole 32.

  Further, due to the elastic deformation of the diaphragm 13, the slide gear 11 moves toward the outer gear 7 and meshes with the outer gear 7 as shown in FIG. 3, and the wheel hub 2 is in a locked state coupled to the front axle 1. Thus, the rotation is transmitted from the front axle 1 to the wheel hub 2.

At this time, the slide gear 11 is held in mesh with the outer gear 7 by the spring 29. Therefore, even when releasing the suction to the second port P _2, locking hubs is maintained in the running state of the four-wheel drive.

Upon switching from the running state of the four-wheel drive shown in FIG. 3 to the running state of the two-wheel drive, a suction force is applied to depressurize the two-wheel drive-side negative pressure chamber 21 to the first port P _1. Due to the reduced pressure, the diaphragm 13 is elastically deformed toward the two-wheel drive side negative pressure chamber 21, and the slide gear 11 connected to the diaphragm 13 moves away from the outer gear 7, and as shown in FIG. The meshing with the outer gear 7 is released, the wheel hub 2 is disconnected from the front axle 1 and becomes free, and the rotation transmission from the wheel hub 2 to the front axle 1 is cut off.

  Further, due to the elastic deformation of the diaphragm 13 toward the two-wheel drive side negative pressure chamber 21, the rivet 17 that couples the outer reinforcing plate 15 and the inner reinforcing plate 16 moves in a direction away from the slide shaft 35. Accordingly, the slide shaft 35 follows the rivet 17 and moves in the axial direction by the elastic force of the elastic member 36. Due to the movement of the slide shaft 35, the stopper pin 33 is moved radially outward by a cam action in which the tapered surface 37 presses the inner end of the stopper pin 33, and as shown in FIG. It protrudes from the outer diameter surface of the front axle 1 and faces the inner side end surface of the slide gear 11 in the axial direction.

Further, the magnet 30 provided in the diaphragm cover 14 attracts the outer reinforcing plate 15 in the switching state to the two-wheel drive. When you break the suction for the first port P ₁ by its adsorption, locking hubs are maintained in the two-wheel drive state.

  In the two-wheel drive maintained state by the magnet 30 as described above, even if the adsorption of the outer reinforcing plate 15 by the magnet 30 is released by a load such as abnormal vibration, the outer end portion of the stopper pin 33 remains on the slide gear 11. The stopper pin 33 prevents the slide gear 11 from moving in the direction of meshing with the outer gear 7 because the inner end surface is opposed to the inner end surface in the axial direction. As a result, the two-wheel drive state can be reliably maintained, and a highly reliable power transmission state can be obtained.

  In the embodiment shown in FIG. 2, the slide shaft 35 is urged toward the rivet 17 by the elastic member 36 incorporated in the closed end portion of the shaft hole 31, and the tip surface is pressed against the rivet 17. As shown in FIG. 4, the tip of the slide shaft 35 is inserted into a center hole 39 formed in the outer reinforcing plate 15 and the inner reinforcing plate 16, and the tip of the slide shaft 35 facing the outside from the outer reinforcing plate 15 is added. It may be fastened and connected to the outer reinforcing plate 15. Reference numeral 40 denotes a caulking portion.

  As described above, by connecting the slide shaft 35 to the outer reinforcing plate 15, the elastic member 36 shown in FIG. 2 can be omitted, and the cost can be reduced by reducing the number of parts.

1 Front axle (driven axle)
2 Wheel hub 6 Hub housing 7 Outer gear 11 Slide gear 13 Diaphragm 14 Diaphragm cover 14a Cylindrical portion 15 Outer reinforcing plate 16 Inner reinforcing plate 21 Two-wheel drive side negative pressure chamber 22 Four-wheel drive side negative pressure chamber 29 Spring 30 Magnet 31 Shaft hole 32 radial hole 33 stopper pin 34 slide mechanism 35 slide shaft 36 elastic member 37 taper surface 38 elastic member

Claims (5)

A wheel hub (2) of the driven wheel is coaxially provided with the driven axle (1) and is rotatably connected to an outer end face of the wheel hub (2) to be connected to the outer end of the driven axle (1). An outer gear (7) that rotates integrally with the hub housing (6) is provided inside the hub housing (6) that covers the outer housing (6), and a slide gear (11) that can mesh with the outer gear (7) is provided on the driven-side axle. A slidably provided at the end of (1), and a diaphragm cover (14) connected to the end surface of the sleeve (8) provided on the outer side of the outer gear (7) and the outer side end of the sleeve (8) The outer periphery of the diaphragm (13) is sandwiched from both sides by the outer periphery of the two-wheel drive side negative pressure chamber (21) on the outer side in the axial direction of the diaphragm (13) and the four-wheel drive side on the inner side in the axial direction. A negative pressure chamber (22), The inner peripheral portion of the diaphragm (13) is sandwiched between the outer reinforcing plate (15) and the inner reinforcing plate (16) from both sides, and the inner reinforcing plate (16) is connected to the slide gear (11). The diaphragm cover is moved to the two-wheel drive by moving the slide gear (11) in the direction to release the meshing with the outer gear (7) by elastic deformation of the diaphragm (13) due to the decompression of the wheel drive side negative pressure chamber (21). The magnet (30) attached to the inner surface of (14) maintains the switching state to the two-wheel drive by the action of magnetically attracting the outer reinforcing plate (15), and the diaphragm by the pressure reduction of the four-wheel drive negative pressure chamber (22) The slide gear (11) is moved to a position meshing with the outer gear (7) by elastic deformation of (13) to switch to four-wheel drive, and the diaphragm (13) is directed to the four-wheel drive chamber side negative pressure chamber (22). In freewheel hub which is adapted to hold the switching state of the energizing springs (29) to the four-wheel drive,
The driven axle (1) is provided with a shaft hole (31) that opens at the shaft end surface, and a radial hole (32) that penetrates from the outer diameter surface to the shaft hole (31), and the radial hole (32). A stopper pin (33) is inserted into the inner side end face of the slide gear (11) in the axial direction when protruding from the outer diameter surface of the driven side axle (1), and the diaphragm (13) A slide mechanism (34) for moving the stopper pin (33) radially outward in conjunction with elastic deformation toward the two-wheel drive negative pressure chamber (21) is provided. Freewheel hub.   The slide mechanism (34) is provided with a slide shaft (35) that slides within the shaft hole (31) in conjunction with the elastic deformation of the diaphragm (13), and an outer side end portion is provided on the slide shaft (35). A tapered surface (37) having a small-diameter end is provided, the stopper pin (33) is urged radially inward by an elastic member (38), and the inner end thereof is in elastic contact with the tapered surface (37). The freewheel hub according to claim 1, wherein the freewheel hub is configured as described above.   The freewheel hub according to claim 2, wherein the slide shaft (35) is urged toward the diaphragm (13) by an elastic member (36) incorporated in the shaft hole (31).   The freewheel hub according to claim 2, wherein an outer side end portion of the slide shaft (35) is connected to the outer reinforcing plate (15) and the inner reinforcing plate (16).   The connection of the slide shaft (35) to the outer reinforcing plate (15) and the inner reinforcing plate (16) is by caulking the shaft end portion of the slide shaft (35) passing through the center hole of the outer reinforcing plate (15). The freewheel hub according to claim 4, wherein the freewheel hub is made of one of screwing and bonding.

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