JP6402403B2 - Roller clutch and transmission using the clutch - Google Patents

Description

Detailed Description of the Invention

The present invention relates to a shift for shifting a vehicle, a construction machine, an agricultural vehicle, or the like.

  In a gear-type transmission of an automobile equipped with an internal combustion engine, the driving force is interrupted until the gears are synchronized at the time of gear shifting, resulting in a gear shift shock. In an alternative torque converter automatic gear shift, extra fuel is sent in advance to eliminate the gear shift shock and output. There is fuel efficiency loss because the side clutch is slid.

  Further, if the gears to be shifted are first meshed using two disc-type clutches and then the clutches are switched, the shift time is shortened, the driving force is not interrupted, and the shift shock and acceleration delay are eliminated.

However, the dual clutch system is complicated and increases in weight because the clutch disk is used frequently and is consumed quickly.
In addition, the dog clutch automatic transmission collides with teeth at high speed, causing unpleasant shift shocks, and requires a number of operating rods for shift shifting, and the convex portions of each rod are guided by meandering grooves. Is complicated.

Japanese Patent Laid-Open No. 2014-077539 FIG. JP2013-133932A (by the applicant) Application number 2013-114668 (by the applicant)

  Since the drive system itself is connected by an elastic body from the engine to the tire, gear shift shock is reduced if gears Gear to Gear with different gear ratios are instantaneously applied with full torque applied. In the conventional shift fork and rod link motion of the speed change operation, it takes 0.1 second or more until the gears having large backlash and different speeds are engaged in synchronization. Also, the grip of the synchronizer ring is insufficient for high engine output and wears out quickly.

The challenge is to achieve a gear-to-gear with full synchronization and light operation, and a self-holding clutch that does not require external force such as hydraulic pressure and has a self-suction force. Be able to shift during acceleration. There is no backlash in the link system of the operating rod and the rigidity is high, and if a gear-to-gear shift can be made in the vicinity of 0.01 seconds, there will be no shock and no break in torque.

The means of claim 1 will be described.
A conical surface is formed between the inner ring raceway ring 1 and the outer ring raceway ring 2 by forming a conical surface on the outer diameter of the inner ring 1 provided around the shaft and turning the outer ring 2 rotating outside thereof into a conical surface. In a roller clutch formed by surrounding a plurality of rollers 3 that are inclined with respect to the rotation shaft, the intermediate shaft is axially positioned between the inner ring raceway 1 and the outer ring raceway 2 and is rotatable. The cam member 9 is interposed between the member 16 and the inner ring 1 or the outer ring 2 and the intermediate member 16, and the cam member 9 and the intermediate member 16 are formed with the concave 15 protrusions 14 so that the intermediate member 16 serves as a fulcrum. 9 is a roller clutch in which the lever principle is configured between the inner and outer rings, with the sliding contact surface between the raceway 9 and the raceway as the working point, and the concave and convex portions are relatively displaced by the operation of the force point 13 of the cam member 9 to engage and disengage the clutch.

Claim 2

2. An always-meshing type transmission that changes gears by the relative displacement of a concave and convex cam of a roller clutch comprising the lever principle of claim 1 between inner and outer wheels.

Effect of the invention

  Since the present invention shifts in an instant even when the driving force is applied, there is no torque interruption and no shift shock or acceleration delay. Since it is a self-holding clutch, it does not require external force to urge it and contributes to weight reduction. The transmission medium depends on the confined oil film and there is no metal contact, so there is no wear. Even if the roller rolling surface wears, it is a conical surface, so it is automatically corrected by spring pressure, and the elastic relative displacement in the axial direction is a torque sensor. So there is no error. Materials, parts, and manufacturing equipment are the same as ISO standard bearings and are inexpensive.

FIG. 1 is a dog clutch diagram for an automatic transmission. ..Outline schematic view of roller clutch ..Schematic diagram of transmission embodiment ..Side view of transmission embodiment ..Roller clutch torque and elastic angular displacement graph ..Correlation graph between external force load and transmission torque ..Measured shock waveforms of dog clutch and roller clutch ..Example of cam phase arrangement from 1st gear to 4th gear ..Explanation of uneven contact angle ..Enlarged view of FIG.

The inner ring 1, outer ring 2 and roller 3 in FIG. 2 are hardened with bearing steel to HRC 60 to 65 and finished to the accuracy conforming to the standard of JISB rolling bearing tapered roller bearings. Roller raceway surface of conical slope of °. A plurality of rollers are inclined (scued) by 10 to 15 °, and a plurality of rollers are arranged on a conical track and rolled. The outer ring 2 of the conical slope whose inner diameter is a one-plane rotation hyperboloid is rotated around the circumscribed circle of the roller. When the inner and outer rings are rotated relative to each other, they start to engage with each other at a wedge angle of about 1.8 °, and the wedge angle changes to about 3 ° and locks with torque load. At this time, an oil film pad solidified and transferred with a film thickness of 0.0003 mm under high pressure can be formed under the rolling surface of the roller. At the same time, due to the Hertzian elastic approach of the contact surface pressure of the roller, the expansion of the outer ring, and the compression elasticity of the inner ring, the roller rolls slightly and the inner and outer rings are relatively displaced in the axial direction by about 7% at maximum.

The adaptability to the transmission of claim 2 will be described.
The number of teeth when the transmission gear transmits torque is normally 1 to 2, whereas the torque capacity of the roller clutch is much larger than the tooth strength because all the rollers on the circumference mesh together. In addition, the fatigue life of rolling contact in recent years is permanent at a contact pressure of 2.5 GPa or less due to the evolution of materials, and the reliability is extremely high. If a clutch having this powerful torque capacity and soft elasticity is installed for each gear of each gear ratio, all the problems described at the beginning can be solved. FIG. 3 shows an embodiment applied to a two-shaft gear transmission of a vehicle. Gear pairs for various speeds are provided around an input shaft 37 and an output shaft 35 so that they are always meshed with each other. A roller clutch in FIG. 2 is engaged with each transmission gear by a spline 7.

The intermediate member 16a of the fulcrum in FIG. 2 is fixed to the gear box 70 as indicated by 16 in FIG. A cam ring 9a (suffixes a, b, c,... Are added to each transmission gear in the figure) is provided between the intermediate member 16a at the right end of FIG. The tip of the lever 13 extended from the cam ring 9a (the suffixes a, b, c,. The intermediate member 16 (suffixes a, b, c,... Are added for each transmission gear in the figure) and the cam ring intermediate member are provided with the concave 15 and the convex 14 in FIG. The action point is gradually boosted along the slope of the fulcrum and moves in the axial direction.

FIG. 8 is a schematic diagram for explanation. Group A shows the ON / OFF operation of the first and second speed irregularities. FIG. 10 shows an embodiment of Clutch to Clutch by operation of a power point when a clutch is mounted on the transmission face to face. When the convex 14a of the first-speed cam ring 9a is engaged with the concave portion 15a of the intermediate member 16a, the first-speed clutch 148a is generated on the tooth surface 7a of the inclined outer spline having the outer diameter of the upper outer ring urged by the disc spring 8. Combined with the thrust and torque of the roller by the torque, the roller bites between the tracks and locks. Since the rear surface (right side in the drawing) of the intermediate ring 16a is located at a position where the convex portion 14b is disengaged from the concave portion 15b, the second-speed gear clutch 148b is turned OFF with the inner and outer raceway intervals gradually widening. When the unevenness is removed by the first-speed cam ring 9a, the cam ring 9b of the second-speed clutch 148b is interlocked with the unevenness to be turned ON.
When both the 1st and 2nd speeds are in the OFF position, the 3rd speed and 4th speed clutch of B described next turn 3rd speed ON and 4th speed OFF.

Next, the operation of the reverse gear 53 shown at the right end of FIG. 3 will be described. The reverse gear 53 is reversely rotated with respect to the other forward gear groups by the reverse idler 51. When the concave and convex cams of the 1st to 4th speed clutches shown in FIG. 3 are turned to the OFF side by the turning connecting bar 177, the concave and convex cams 14 and 15 of all the forward gear groups are disengaged and become neutral. Then, 13 g is rotated via a gear by a turning lever 13 e integrated with the turning connecting bar 177, and the uneven cam 14 f of the reverse gear clutches 148 d and 148 e (arranged on the input shaft 37 in FIG. 4). , And 15f are turned ON. Thus, the reverse gear clutches 148d and 148e are both engaged and driven backward. During forward travel, the reverse gear clutches 148d and 148e are disengaged and the raceway wheel is separated and held OFF, so that the gear does not rotate with the input / output shaft and remains stationary.

  In FIG. 3, only the first gear around the input shaft 37 is a double-row tandem. In the case of the double row tandem arrangement, the roller skew angle α ° is reversed as shown in the figure. The reason for the double-row tandem is to double the clutch damper effect in order to absorb low-speed torque fluctuations in diesel engines and the like. (B) As shown by the thick line in FIG. 3, the first-speed torque is transmitted from the left inner ring of the tandem to the outer ring via the roller and from the outer ring to the inner ring on the right side of the first gear 6a1. If the tandem is entered, the relative displacement of the inner and outer rings cancels out with the floating outer ring, so no spline is required.

C) When the roller rolling surface is lubricated with an additive such as organic molybdenum (the sealing material is not shown in the figure for simplicity), it creeps at a slow speed, so that the engine can idle even when the car is stopped. Creep running at a very low speed is also possible. If the rotation is slightly increased, the clutch is connected and driven. The creep speed can be doubled by selecting the oil agent and making it tandem double row. In the double row, the rollers need to be in contact with the conical raceway surface simultaneously, and the raceway surface dimensions of the double row must be the same with high accuracy and are adjusted by the shim 173.
If all the clutches are turned off, torque is not transmitted to the shaft at all, so it becomes neutral, and the existing fluid couplings and friction plate clutches can be reduced.

Regarding clutch torque engagement / disengagement means, JP-A-2013-133932 and Application No. 2013-114668 of related patent document 3 are available.
When the clutch is shut off while the full torque is applied, if the torque is about 20 rollers with a length of 20 mm, the rollers will bite and bite with a high surface pressure of 3 GPa, so it is necessary to remove the static friction of iron If the coefficient μ ₀ is calculated with 0.12, it requires 14 tons of thrust to separate and is not easy. The solution is that if the rolling force of the roller rolling on the conical slope is unbalanced, the transmission torque is drastically reduced (slip is generated) as shown in FIG. 6, that is, the roller is applied to the high-pressure viscous oil film so that the fluid joint is momentarily interposed. It floats and rolls slightly to a half-clutch state. Using this principle, a couple is applied on the uneven slope of the cam to separate it while leaving the torque. The clutch that receives the torque absorbs the differential rotation by the torsional elastic cushion of the clutch itself and receives it gently.

As shown in FIG. 9, when the contact angle of the initial contact 171 is reduced as shown in FIG. 9, a wedge action occurs due to the sliding frictional resistance between the outer ring side surface of the rotating clutch and the cam ring, and the convex part of the cam ring Along with the speed, it is pushed out by the concave slope, and one part of the outer ring of the clutch is pushed, and a couple acts on the clutch and comes off in 0.01 seconds or less.

  The clutch of the gear before receiving torque receives the urging force of the urging spring 8 at the convex part of the cam ring and becomes a stopper, so the outer ring and the roller are in a non-contact state. Pressed by a disc spring, the raceway approaches along the concave slope and the roller meshes with the raceway. When engaged, when the gear shifts to the upper gear with a small gear ratio, the lower gear with the lower speed becomes overrunning. When shifting from the upper gear to the lower gear under full torque load, the torque is transferred to the lower gear while the torque remains in the upper gear, and the clutch of the upper gear is released after the transfer. When the running clutch is overrunning, friction loss is caused, so that the uneven position is shifted and the roller is set to non-contact OFF.

3 and 8 are described in four stages for simplification, multi-stages may be achieved by appropriately increasing gears. In FIG. 8, when the unevenness of the cam of the clutch of the first speed gear is fitted, the unevenness of the other clutches is removed. In FIG. 3, the end of the operating lever (power point) 13 extended from the cam ring 9 at the point of action is connected to the rod 177 of the turning actuator in FIG. When the swivel tooth 60 is driven by a servo motor 62 having a high response speed, the cam position of the speed change gear required for instantaneous travel with high accuracy is obtained. This is an always-meshing type transmission that can also perform interlaced shifting. In this case, the clutch capacity is matched to the impulse.

The cam position is controlled by the servo motor. The linear potentiometer 176 of the displacement sensor (representative illustration) attached to the intermediate member of the second gear shown in FIG. 3 measures the displacement between the side surface of the outer ring of the clutch and the intermediate member and converts this to torque. Then, the optimum gear ratio is selected based on the engine speed, the air-fuel ratio, and the accelerator opening signal, and the servo motor is turned to a position where the unevenness of the transmission gear is fitted.

The zero point reset of the torque sensor is performed by reverse rotation or power OFF signal. In order to ensure the restoration accuracy of the reset zero point, the direction of the spline on the spline of the outer ring of the clutch is reversed by overrunning (reverse rotation), and the frictional resistance during idling is converted to thrust by the spline teeth to bring the roller into the track. Press stably. In particular, oil freezing in cold regions and overrunning when restarting after long-term storage prevent unstable movement such as roller slipping out. Further, even if the disc spring 8 is frozen and fixed, foreign matter is mixed into the tooth surface 7a of the spline, and the roller and the cage are frozen, the assist thrust is effectively operated.
In this configuration, when an abnormality such as slippage or engagement failure occurs in the clutch, the abnormality can first be detected from the torque value of the torque sensor.

Since the outer ring side surface of all clutches is in frictional sliding contact with the convex part of the cam ring, a thrust rolling bearing is interposed (not shown) or the biasing pressure of the disc spring is reduced. It is essential that the frictional resistance of the tooth surface 7a of the spline is stable and small. For this reason, the surface pressure of the tooth when torque is applied by interposing a wave plate spring with dimples containing oil between the tooth surfaces 7a. The oil is squeezed out to float on the oil film and displaced. (Drawing is omitted) The required distance for the displacement is only 5 mm or less of the axial relative displacement amount of the inner and outer rings.

The reason why the clutch is suitable for shifting will be described from the basic characteristics. FIG. 6 shows an actual measurement value of a decrease in transmission torque when an external force is applied to the clutch to cause an unbalance in the tightening force of the roller. FIG. 5 shows measured values of the clutch torque load and elastic torsional displacement (degree). At the initial stage of the load, a gentle displacement starts to engage with soft elasticity, and a torque capacity near the surface pressure of 3 GPa is obtained. Its elastic twist angle reaches about 80 °. FIG. 7 is a waveform when the conventional dog clutch of FIG. 1 is forcibly engaged with a collision. For comparison, the waveform of the roller clutch of FIG. 2 by the same method is also shown. The roller clutch does not have a peak waveform and starts to be engaged in 0.02 seconds.
In addition, a specific oil agent such as molybdenum disulfide-added oil creeps at a constant speed from a small torque to a huge torque. (Not shown)

An embodiment of claim 1 is shown in FIG.
Concave and convex are described in the representative example of converting the operation of the force point into axial displacement, but it is possible to engage a pin in a groove meandering in the axial direction or to interpose a ball or roller between the curved concave grooves facing each other. In short, it can be attributed to the interposition of the fulcrum force point action point of the lever principle between the inner and outer races. (Not shown)

An embodiment of claim 2 is shown in FIG. Embodiments FIGS. 3 and 4 are schematic sectional views of a transmission (not shown), and a servo motor is illustrated for a speed change operation. However, each gear may be ON / OFF controlled by an electromagnetic solenoid. (Not shown)

1a, 1b · · Clutch inner ring 2 · · Clutch outer ring 3 · · Roller 4 · · Cage 6a to 6d · · Speed gear 8 · · Belleville springs 9a to 9f · · Cam rings 13a to 13f · · Cam ring operating lever 14a · 14f ··· convex portions 16a to 16d of cam ring · · intermediate member 35 · · output shaft 37 · · input shaft 51 · · reverse idler 52 and 53 · · reverse gear 60 · · swivel swing gear 61 · · swivel gear 62 ·・ Slewing drive servo motors 148a to 148f ・ ・ Clutch unit 173 ・ ・ Shim 174 ・ ・ Serration tooth 176 ・ ・ Torque sensor 177 ・ ・ Swivel connecting bar

Claims (2)

Between the conical surface formed on the outer diameter of the inner ring 1 fixed to the shaft and the conical surface formed on the inner diameter surface of the outer ring 2 rotating on the outer side, the cage 4 is inclined with respect to the rotation axis. When a plurality of rolling rollers 3 are arranged and a torque is applied, the rollers bite between the races to form a confined oil film on the contact surface, and increase or decrease the amount of torque transmitted by the shear and viscosity resistance of the oil film. In the roller clutch, the intermediate member 16 is provided on the side of the inner ring and the outer ring so that the inner ring and the outer ring can be rotated relative to each other in the axial direction, and between the inner ring 1 or the outer ring 2 and the intermediate member 16. The cam member 9 having a curved surface that is converted into thrust is interposed between the intermediate member 16 and the slidable contact surface between the cam member 9 and the inner ring 1 or the outer ring 2 as a working point. 9 and the intermediate member 16, relative to the cam member 9, and the intermediate portion 16. A roller provided with the concave-convex cam that creates a half-clutch state in which torque is left in the roller clutch by applying a couple to the roller clutch with a force that changes the set width of the roller 16, causing unbalance in the tightening force of the roller clutch. A transmission that changes speed by a relative displacement operation of the concave-convex cam of the roller clutch according to claim 1.

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