JP2007078033A - Power transmitting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmitting apparatus which can supply minimum essential lubricating oil mainly to the whole of a spline portion of the power transmitting shaft in the circumference. <P>SOLUTION: The apparatus includes a power transmitting shaft which has a spline portion on its outer peripheral surface and has an oil supplying path for supplying the lubricating oil to the spline portion, and a driven rotary member which engages with the spline portion and is driven by the spline portion, wherein the oil supplying path is formed in the power transmitting shaft and has an axial supply path elongating in the axial direction, annular oil grooves surrounding the spline portion, and oil holes connecting the annular oil groove and the axial supply path. Because the annular oil grooves formed in the spline portion supplies the lubricating oil into the circumference of the spline portion in this power transmitting apparatus, the whole of the spline portion can be lubricated, and the fretting wear due to the lack of lubricating oil hardly occurs. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power transmission device such as a gear transmission having a spline joint portion.

  The power transmission device is used, for example, to transmit rotational power of an automobile engine to drive wheels. A typical power transmission device is a synchromesh transmission mechanism. The speed change mechanism includes a power transmission shaft, a clutch hub splined to the power transmission shaft, a pair of gears positioned on both sides of the clutch hub and loosely fitted on the power transmission shaft, and slidable on each gear. And a pair of synchronizer rings held in the frame. The clutch hub is moved by the sleeve to one or the other gear in the axial direction, and the clutch hub is coupled to one or the other gear synchronized via the synchronizer ring. As a result, the rotational power of the power transmission shaft is transmitted to one or the other gear via the clutch hub, and a shift is performed.

  In order to perform a smooth speed change at the time of the speed change, it is desirable that the friction of the spline part and the sliding part of the synchronizer ring is small. In the conventional example, as shown in Patent Document 1, an oil supply passage extending in the axial direction is formed at the center of the power transmission shaft, and an oil hole branched in a radial direction from the oil supply passage is formed as a spline on the outer periphery of the power transmission shaft. The part is opened at a position corresponding to the clutch hub. An annular space is formed between the clutch hub and the pair of gears, and a path through which the annular space communicates with the oil hole is formed inside the clutch hub. Thus, a path for supplying the lubricating oil from the annular space to the sliding portion of the synchronizer ring is formed, and the lubricating oil is supplied from the oil supply path in the power transmission shaft to the sliding portion of the synchronizer ring. .

  In Patent Document 2, a hydraulic power take-out shaft is driven from a timing gear of a diesel engine via a hydraulic gear, and power is taken out from the hydraulic power take-out shaft to a main hydraulic pump and a power steering sub-hydraulic pump. The hydraulic power take-out shaft has a shape in which a space is formed in the axial direction like a pipe, and a spline portion that is splined to the main hydraulic pump and the sub hydraulic pump is formed on the inner peripheral surface of the shaft. The spline portions are formed at both ends in the axial direction, and the hydraulic power take-out shaft has a hollow portion at a central portion sandwiched between the spline portions at both ends. And in order to lubricate a spline part, the oil supply path of the radial direction opened to the hollow part inside from the exterior of a hydraulic power extraction shaft is formed. Lubricating oil supplied to the hollow portion from the outside of the hydraulic power take-out shaft accumulates in the hollow portion and flows to the spline portions at both ends of the hollow portion to be lubricated.

Patent Document 2 is different from the present invention in that the spline part is outside and inside the power shaft, but is common with the present invention in that an oil supply path is formed in the power shaft to lubricate the spline part. It was given as a prior art.
JP-A-5-10346 JP 2001-263024 A

  In the gear transmission of Patent Document 1, an oil supply path that opens to the spline portion is formed inside the power transmission shaft, and an annular space is formed between the clutch hub and the pair of gears. An oil supply path for supplying lubricating oil to the annular space is formed at a position facing and communicating with the opening of the spline portion of the power transmission shaft inside the clutch hub. Therefore, the lubricating oil supplied from the power transmission shaft flows into the annular space from the oil supply passage in the clutch hub that is partially communicated, and the remaining flows through the gap between the spline protrusion and the spline groove near the opening. Therefore, the sliding part of the synchronizer ring is mainly lubricated, and the spline part tends to be short of lubricating oil. In particular, when the power transmission shaft and the clutch hub rotate at a high speed, the lubricating oil that receives the outward centrifugal force of the spline part easily flows into the oil supply path inside the clutch hub that opens in the centrifugal force direction. The rest is supplied to the spline protrusion and spline groove of the clutch hub near the opening, and the splashed lubricating oil is the spline groove and spline protrusion of the power transmission shaft facing the spline protrusion and spline groove of the clutch hub. Flowing into. The lubricating oil is obstructed by the spline protrusions and spline grooves that are spline-coupled to each other, and does not flow in the circumferential direction but flows in the axial direction. As a result, the lubricating oil flows out from the spline portion to the side surfaces of the clutch hub and the synchronizer ring, and the spline portion tends to be short of lubricating oil.

  On the other hand, in the lubricating device for the hydraulic power take-off shaft of the engine disclosed in Patent Document 2, the opening on the outside of the oil supply path formed on the hydraulic power take-out shaft is in contact with the lubricating oil surface, and the opening on the inside of the hydraulic power take-out shaft. The part opens to the hollow part of the hydraulic power take-out shaft. Since the lubricating oil accumulates in the hollow portion and then flows into the spline portion, a certain amount of oil is required to lubricate the spline portion. That is, when the amount of lubricating oil is small, the oil level of the lubricating oil accumulated outside the hydraulic power take-out shaft is lowered, and the lubricating oil supplied to the hollow portion inside the hydraulic power take-out shaft is reduced. As a result, if the amount of lubricating oil flowing from the hollow portion decreases, the spline portion tends to be short of lubricating oil.

  The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a power transmission device that can reliably lubricate the entire circumferential direction of the spline portion of the power transmission shaft only by supplying the minimum amount of lubricating oil. And

Means for Solving the Problems and Effects of the Invention

  A power transmission device according to the present invention includes a power transmission shaft having a spline portion on an outer peripheral surface and having an oil supply path for supplying lubricating oil to the spline portion, and a driven rotating member connected to the spline portion to transmit power. The oil supply path has an axial supply path formed in the power transmission shaft and extending in the axial direction, a ring-shaped oil groove that goes around the spline portion, the ring-shaped oil groove, and the shaft It has the oil hole which connects a direction supply path, It is characterized by the above-mentioned.

  In the power transmission device of the present invention, the lubricating oil is supplied from an axial supply passage formed in the power transmission shaft and extending in the axial direction to a circumferential oil hole opened in a spline portion outside the power transmission shaft. Is done. And it is supplied to the ring-shaped oil groove of a spline part from an oil hole, and each flows in an axial direction by each spline groove from this ring-shaped oil groove. Thus, the lubricating oil can be supplied to the entire spline portion, and fretting wear hardly occurs. For example, even when the amount of lubricating oil is small, the lubricating oil can flow in the circumferential direction through the ring-shaped oil groove from the oil hole in the spline part, so it branches at each spline protrusion and spline groove and flows in the axial direction. It is possible to lubricate the entire part.

  Further, when the power transmission shaft and the clutch hub rotate at high speed, the lubricating oil is first supplied from the oil hole to the spline portion of the driven rotating member. However, since there is not enough space for the lubricating oil to remain in the spline portion of the driven rotating member, a part of the lubricating oil flows in the axial direction through the spline protrusion and the spline groove of the driven rotating member. The remaining lubricating oil rebounds in the ring-like oil groove of the spline portion of the power transmission shaft and flows in the circumferential direction, and flows in the axial direction into each spline protrusion and spline groove, so that the lubricating oil is not easily insufficient.

  The ring-shaped oil groove is preferably formed in the central portion in the axial direction of the spline portion of the power transmission shaft. As a result, the lubricating oil can be supplied from the ring-shaped oil groove at equal distances on both sides in the axial direction, and the lubricating oil can be supplied more reliably to the spline portion.

  The depth of the ring-like oil groove is preferably formed deeper than the depth of the spline portion groove. The spline ridge of the driven rotating member is joined to the spline groove on the power transmission shaft side, but by forming the ring-shaped oil groove deeper than the spline groove, the flow of lubricating oil in the circumferential direction is covered. It becomes difficult to be blocked by the spline protrusions of the drive rotating member.

  Further, when an oil hole is machined in the spline portion of the power transmission shaft with a machining drill, the tip of the drill is difficult to escape from the oil hole forming portion by being guided by the ring-shaped oil groove, and the workability of the oil hole is improved.

  When the driven rotating member is a clutch hub, the lubricating oil is supplied to the entire spline portion of the power transmission shaft and the spline portion of the clutch hub. Similarly, when the driven rotating member is a gear, lubricating oil is supplied to the spline portion of the power transmission shaft and the entire spline portion of the gear.

  Hereinafter, a power transmission device (transmission device) according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  The power transmission apparatus of an Example is shown in FIGS. 1-3. FIG. 1 is a detailed cross-sectional view of a synchronous portion of a power transmission shaft. FIG. 2 is an explanatory plan view of the spline portion of the power transmission shaft. FIG. 3 is an enlarged view of a main part of FIG.

  In FIG. 1, a power transmission device 1 includes a power transmission shaft 2, a clutch hub 3, a pair of gears (a small gear 41 and a large gear 42), and a pair of synchronizer rings. The power transmission shaft 2 includes a spline portion 21 and a ring-shaped oil groove 22 at the center portion of the outer peripheral surface, and includes an oil supply path that supplies lubricating oil to the ring-shaped oil groove 22 inside. As shown in FIG. 2, the spline portion 21 includes a plurality of convex spline protrusions 211 and a plurality of concave spline grooves 212 formed in the circumferential direction. A ring-shaped oil groove 22 that makes a round in the circumferential direction at the center in the axial direction of the spline portion 21 is formed by cutting out the spline protrusion 211 and the spline groove 212. Returning to FIG. 1, the oil supply path extends in the radial direction connecting the axial supply path 23 and the ring-shaped oil groove 22, and is formed by extending in the axial direction at the center of the power transmission shaft 2. An oil hole 24 is formed.

  The clutch hub 3 has a spline portion including a plurality of spline protrusions and a plurality of spline grooves formed on the inner peripheral surface, and a sleeve 31 formed on the outer peripheral surface. The spline portion is splined to the spline portion 24 of the power transmission shaft 2, and can slide in the axial direction with respect to the power transmission shaft 2 by an external force applied from the sleeve 31.

  The small gear 41 and the large gear 42 have different radii, and are loosely fitted to the power transmission shaft 2 via bearings 5 on the left and right in the axial direction in FIG. The bearing 5 is formed in a radial direction communicating with the ring-shaped oil groove 26 from a ring-shaped oil groove 26 opened in the outer peripheral portion of the power transmission shaft 2 at a position facing the bearing 5 (bearing facing portion 25). Lubricating oil is supplied through the hole 27. The small gear 41 and the large gear 42 have clutch gears 43 provided integrally with the respective gears on the side facing the clutch hub 3.

  The synchronizer ring includes an inner ring 61, a middle ring 62, and an outer ring 63. The synchronizer ring is assembled on a tapered cone portion 44 provided integrally with the small gear 41 and the large gear 42. The inner ring 61 is located on the tapered cone portion 44, the middle ring 62 is located on the inner ring 61, and the outer ring 63 is located on the middle ring 62.

  When the sleeve 31 is moved in the axial direction by operating a shift fork (not shown), the outer ring 63 is pressed to the middle ring 62, the middle ring 62 is pressed to the inner ring 61, and the inner ring 61 is pressed to the small gear 41 or the large gear 42, respectively. Let As a result, synchronization between the clutch hub 3 and the small gear 41 or the large gear 42 is started via these three synchronizer rings. As the sleeve 31 further moves in the axial direction, the three synchronizer rings are pressed more strongly by the small gear 41 or the large gear 42 to complete the synchronization. At the same time, the sleeve 31 meshes with the outer ring 63 and meshes with the clutch gear 43. Thus, the small gear 41 or the large gear 42 is coupled to the power transmission shaft 2 via the clutch hub 3, and the rotation of the power transmission shaft 2 is transmitted to the small gear 41 or the large gear 42.

  During the speed change, the lubricating oil is supplied from the axial supply path 23 of the power transmission shaft 2 to the oil hole 24 to the spline portion 21 where the clutch hub 3 is splined and the sliding portion where the gear and the synchronizer ring are connected. . Since the ring-shaped oil groove 22 is cut slightly deeper than the spline groove 212, the lubricating oil flowing out from the oil hole 24 is supplied along the ring-shaped oil groove 22 in the circumferential direction. The lubricating oil branches from the ring-shaped oil groove 22 at each spline groove 212 and is supplied in the axial direction, so that the entire width direction of the spline portion 21 is lubricated. Thus, the lubricating oil that has lubricated the entire spline portion 21 in the circumferential direction and the axial direction oozes out from both ends of the spline portion in the axial direction, and flows between the clutch hub 3 and the gears and synchronizer rings to lubricate the sliding portions. To do. By forming the ring-shaped oil groove 22 in the spline portion 21, it is possible to lubricate the entire spline portion 21 with the minimum necessary lubricating oil.

  Even if the power transmission shaft 2 and the clutch hub 3 rotate at high speed, the lubricating oil flows in the circumferential direction between the ring-shaped oil groove 22 and the spline portion 21 of the clutch hub 3, and lubricates each spline protrusion and spline groove. As a result, the spline is less likely to run out of lubricating oil and fretting wear is unlikely to occur.

(Best Mode for Carrying Out the Invention)
The power transmission device of the present invention transmits power from one power transmission shaft (drive unit) to the other power transmission shaft (driven unit).

  The power transmission shaft of the drive part has a spline part on its outer peripheral surface, and this spline part may be formed in the whole axial direction or only in part, but at least the driven rotating member is splined Formed in a portion to be formed and has a predetermined length. In the spline portion, a plurality of spline protrusions and a plurality of spline grooves are alternately formed in the circumferential direction.

  The power transmission shaft has an axial supply path, an oil hole, and a ring-shaped oil groove for supplying lubricating oil to the spline portion and / or the bearing facing portion. An axial supply path extending in the axial direction is formed inside the power transmission shaft. The axial supply path may be formed in the entire axial direction, or may be formed from one end to a portion communicating with the oil hole. The oil hole extends in the radial direction from the axial supply path, and is formed so as to open to the spline portion and / or the bearing facing portion of the outer peripheral portion of the power transmission shaft. At least one oil hole is formed at each spline portion and / or bearing facing portion, and two or more oil holes may be formed radially from the axial supply path as necessary. The ring-shaped oil groove is formed in a direction transverse to the spline portion and / or the bearing facing portion of the power transmission shaft, that is, in the circumferential direction, and is formed at a position where the oil hole opens in the axial direction. At least one ring-shaped oil groove is formed in the spline portion and / or the bearing facing portion. When there are a plurality of spline portions and / or bearing facing portions, at least one ring groove is formed.

  The driven rotating member is a member for transmitting the power shifted from one power transmission shaft to the other power transmission shaft. For example, in a transmission of an automobile, a clutch hub that is splined to the power transmission shaft and / or Gears are possible. The inner peripheral surface has a spline portion that is splined to the spline portion of the power transmission shaft.

  When the driven rotating member is a gear, the gear is splined to the power transmission shaft. This gear meshes with a gear attached at the time of other power transmission. The power of one power transmission shaft is shifted by a gear through a pair of gears and transmitted to the other power transmission shaft.

  The synchronizer ring is used when a rotation of a power transmission shaft is transmitted to a gear in a synchromesh transmission mechanism which is a kind of transmission. The synchronizer ring may be one or two or more, and has a function of synchronizing with a clutch hub splined to the power transmission shaft.

It is sectional drawing of the synchronous part of a power transmission shaft. It is plane explanatory drawing of the spline part of a power transmission shaft. It is a principal part enlarged view of FIG.

Explanation of symbols

1: Power transmission device 2: Power transmission shaft 21: Spline portion 211: Spline protrusion 212: Spline groove 22, 26: Ring-shaped oil groove 23: Axial supply path 24, 27: Oil hole 25: Bearing facing portion 3: Clutch hub 31: Sleeve 41: Small gear 42: Large gear 43: Clutch gear 5: Bearing 61: Inner ring 62: Middle ring 63: Outer ring

Claims (5)

A power transmission device having a power transmission shaft having a spline portion on an outer peripheral surface and having an oil supply passage for supplying lubricating oil to the spline portion, and a driven rotating member connected to the spline portion to transmit power. ,
The oil supply path is formed in the power transmission shaft and extends in the axial direction, a ring-shaped oil groove that goes around the spline portion, and an oil hole that connects the ring-shaped oil groove and the axial supply path. A power transmission device comprising:   The power transmission device according to claim 1, wherein the ring-shaped oil groove is located in a central portion in the axial direction of the spline portion of the power transmission shaft.   The power transmission device according to claim 1 or 2, wherein a depth of the ring-shaped oil groove is deeper than a depth of the groove of the spline portion.   The power transmission device according to claim 1, wherein the driven rotating member is a clutch hub. The power transmission device according to claim 1, wherein the driven rotating member is a gear.

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