Power transmission device

Abstract

To provide a power transmission device capable of supplying oil to an object to be lubricated. [Solution] The power transmission device according to the present invention comprises a case and a shaft. The shaft extends in a first direction. A first oil line is provided inside the shaft. The case is provided with a recess, a first hole, a second hole, a second oil line, and a rib. The end of the shaft in the first direction is inserted into the recess. The first hole extends in the vertical direction and is connected to the outside of the case and to the recess. The second oil line is a hole that extends in the vertical direction, is aligned in a straight line with the first hole, and is configured to be connectable to the first oil line by being connected to the recess. The second hole connects the space inside the case to the first hole. The rib is a projection provided on the inner circumferential surface of the case, is located above the recess and the second hole, and overlaps with the second hole when viewed from below.

Description

Technical Field

[0001] The present invention relates to a power transmission device.

Background Art

[0002] As an invention related to a conventional power transmission device, for example, a lubrication structure of a transmission described in Patent Document 1 is known. This lubrication structure has a case rib provided on the inner surface of the case. The case rib is provided at a position above the portion of the gear immersed in the oil accumulated in the case, above the lubrication target, and in the vicinity of the lower side of the shaft disposed above the gears in the transmission. This lubrication structure supplies the oil scraped up by the rotation of the gears in the transmission to the lubrication target in the transmission.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As described above, there is a need for a power transmission device that can supply oil to a lubrication target.

[0005] Therefore, an object of the present invention is to provide a power transmission device that can supply oil to a lubrication target.

Means for Solving the Problems

[0006] The first aspect is that the power transmission device includes a case and a shaft, the shaft extends in a first direction, a first oil line is provided inside the shaft, The case is provided with a recess, a first hole, a second hole, a second oil line, and a rib. The first end of the shaft is inserted into the recess, The first hole extends in the vertical direction and is connected to the outside of the case and the recess. The second oil line is a hole extending in the vertical direction, aligned in a straight line with the first hole, and connected to the recess, thereby being configured to be connectable to the first oil line. The second hole connects the internal space of the case to the first hole. The rib is a projection provided on the inner circumferential surface of the case, located above the recess and the second hole, and overlapping with the second hole when viewed from below. It is a power transmission device.

[0007] The second aspect is, The power transmission device further includes an object to be lubricated, The object to be lubricated is housed in the case, The inner circumferential surface of the aforementioned case is provided with a boss and a guide portion. The boss is a projection provided on the inner circumferential surface of the case, and, when viewed in the first direction, surrounds the recess. The guide portion includes a portion located below the rib and guides the oil that has flowed along the rib or the boss to the object to be lubricated. This is the power transmission device described on the first side. [Effects of the Invention]

[0008] According to the present invention, oil can be supplied to the object to be lubricated. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is an exploded perspective view of the power transmission device 10. [Figure 2] Figure 2 is a cross-sectional view of the power transmission device 10. [Figure 3] Figure 3 is an exploded perspective view of the power transmission device 10. [Figure 4] Figure 4 is an exploded perspective view of the power transmission device 10. [Modes for carrying out the invention]

[0010] (Embodiment) [Structure of the power transmission device 10] The structure of a power transmission device 10 according to one embodiment of the present invention will be described below with reference to the drawings. Figures 1, 3, and 4 are exploded perspective views of the power transmission device 10. Figure 2 is a cross-sectional view of the power transmission device 10. Hereinafter, the direction in which the shaft 18 extends is defined as the left-right direction (first direction and second direction). Therefore, the second direction is the opposite direction to the first direction. Also, the up-down direction in the drawing of Figure 1 is defined as the up-down direction. In this embodiment, the up-down direction coincides with the vertical direction. The front-back direction is perpendicular to the up-down direction and the left-right direction.

[0011] The power transmission device 10 is a device that transmits power generated by the power source of an automobile. The power transmission device 10 is, for example, an automatic transmission or a differential transmission in an automobile. In this embodiment, the power transmission device 10 is an automatic transmission. As shown in Figures 1 to 3, the power transmission device 10 comprises a case 12, a sleeve 14 (see Figure 3), a plate 16 (see Figure 3), a bearing 17 (see Figure 2), a shaft 18, a differential bearing (a lubricating object, not shown), and a bolt 22.

[0012] First, let's describe case 12. Case 12 is the case for an automatic transmission. Therefore, the case is a container that houses multiple shafts and gears. Figures 1 to 4 are enlarged views of the vicinity of the end of the shaft 18 inside case 12. As shown in Figure 1, case 12 has a main surface S0 (inner circumferential surface) facing left. Case 12 is also provided with recesses G0, G4, and G5, a first hole h1 (see Figure 2), a second hole h2, a second oil line OL2 (see Figure 2), a boss 12a, a rib 12b, a guide portion 12c, and a rib 12d.

[0013] The recess G0 is formed by the part of the recess G0 being recessed to the right with respect to the part around the recess G0 on the main surface S0. The recess G0 includes a first recess G1, a second recess G2, and a third recess G3.

[0014] Each of the first recess G1, the second recess G2, and the third recess G3 forms a space having a cylindrical shape. The first recess G1, the second recess G2, and the third recess G3 are arranged in this order from right to left. The central axis of the first recess G1, the central axis of the second recess G2, and the central axis of the third recess G3 coincide. Also, the diameter of the first recess G1 is smaller than the diameter of the second recess G2. The diameter of the second recess G2 is smaller than the diameter of the third recess G3.

[0015] The boss 12a is a protrusion provided on the main surface S0 (inner peripheral surface) of the case 12. The boss 12a is formed by the part of the boss 12a protruding leftward (second direction) with respect to the part around the boss 12a on the main surface S0. The boss 12a has an annular shape when viewed from the right direction. The boss 12a surrounds the recess G0 when viewed from the right direction (first direction).

[0016] As shown in FIG. 2, the first hole h1 is connected to the outside of the case 12 and the recess G0. More specifically, the first hole h1 extends in the vertical direction. The upper end of the first hole h1 is located on the upper surface of the case 12. The lower end of the second hole h2 is located at the upper part of the side surface of the third recess G3.

[0017] The second oil line OL2 is connected to the recess G0. More specifically, the second oil line OL2 extends in the vertical direction. The second oil line OL2 is located below the first hole h1. The second oil line OL2 is aligned with the first hole h1. The upper end of the second oil line OL2 is located at the lower part of the side surface of the third recess G3. The lower end (not shown) of the second oil line OL2 is located on the main surface S0 of the case 12.

[0018] The second hole h2 connects the internal space of case 12 to the first hole h1. More specifically, the second hole h2 extends in the left-right direction. The right end of the second hole h2 is located on the side of the first hole h1. The left end of the second hole h2 is exposed to the internal space of case 12. As a result, the second hole h2 is located above the recess G0. That is, when viewed from below, the second hole h2 overlaps with the recess G0.

[0019] The rib 12b is a projection provided on the main surface S0 (inner circumferential surface) of the case 12. More specifically, the rib 12b is formed by a portion of the rib 12b projecting to the left relative to the surrounding portion of the main surface S0. The rib 12b has a plate shape with an upper main surface and a lower main surface. When viewed from the right, the rib 12b is curved to project upward. The center of the rib 12b in the front-rear direction is located above the front end and rear end of the rib 12b.

[0020] Rib 12b is located above recess G0 and second hole h2. When viewed from below, rib 12b overlaps with recess G0 and second hole h2. The front end of rib 12b is located in front of the front end of second hole h2. The rear end of rib 12b is located behind the rear end of second hole h2.

[0021] The recess G5 is formed on the main surface S0 by the recess G5 being recessed to the right relative to the surrounding portion of the recess G5. The recess G5 forms a cylindrical space. The recess G5 is located behind the first recess G1. The recess G5 supports a parking pole shaft (not shown).

[0022] Rib 12d is a projection provided on the main surface S0 of case 12. However, the height (length in the left-right direction) of rib 12d is shorter than the height (length in the left-right direction) of boss 12a. When viewed to the right, rib 12d extends in the front-rear direction. The front end of rib 12d is connected to boss 12a. The rear end of rib 12d is connected to recess G5. As a result, rib 12d is located behind and below rib 12b.

[0023] The recess G4 is formed on the main surface S0 by the recess G4 being recessed to the right relative to the surrounding portion of the recess G4. The recess G4 forms a cylindrical space. The recess G4 is located behind and below the first recess G1. A groove X is provided in the recess G4. The groove X is connected to the upper part of the recess G4.

[0024] The guide portion 12c is a slope facing to the left rear. When viewed to the right, the guide portion 12c extends diagonally downward to the right. The guide portion 12c includes a portion located below the rib 12b. In this embodiment, the guide portion 12c is located below the rib 12b. The upper end of the guide portion 12c is located behind and below the boss 12a. Also, the upper end of the guide portion 12c is located below the rear end of the rib 12b. The lower end of the guide portion 12c is connected to the groove X of the recess G4. Furthermore, the width of the guide portion 12c in the front-rear direction decreases as it goes downward.

[0025] Case 12, as described above, is made of, for example, cast iron. Specifically, case 12 is formed by casting. Next, the case 12 is cut by drilling to form the first recess G1, the second recess G2, and the third recess G3. Finally, the case 12 is cut by drilling to form the first hole h1 and the second hole h2. In this case, after forming the first hole h1 with a drill, the drill is lowered without removing it from the first hole h1 to form the second hole h2 with a drill.

[0026] As shown in Figure 3, the sleeve 14 has a cylindrical shape with a central axis extending in the left-right direction. However, as shown in Figure 2, the sleeve 14 is provided with a hole H. The hole H connects the inner and outer surfaces of the sleeve 14. The sleeve 14 is attached to the first recess G1. When the sleeve 14 is attached to the first recess G1, the hole H connects to the second oil line OL2. The sleeve 14 described above is made of carbon steel.

[0027] Plate 16 is a plate-like member with an annular shape when viewed from the right. Plate 16 is attached to the second recess G2. Plate 16 is fixed to the case 12 and also fixes the sleeve 14. Plate 16 as described above is made of carbon steel.

[0028] The bearing 17 is a ball bearing. The bearing 17 is supported by the case 12. In this embodiment, as shown in Figure 2, the bearing 17 is mounted in the third recess G3. As a result, the bearing 17 is located to the left of the plate 16. The bearing 17 is also in contact with the plate 16. As a result, the bearing 17 restricts the plate 16 from moving in the left-right direction.

[0029] The shaft 18 extends to the right (first direction), as shown in Figure 1. The shaft 18 includes a first part 18a, a second part 18b, and a third part 18c. The first part 18a, the second part 18b, and the third part 18c have a cylindrical shape. The diameter of the first part 18a is smaller than the diameter of the second part 18b. The diameter of the second part 18b is smaller than the diameter of the third part 18c. The first part 18a, the second part 18b, and the third part 18c are arranged in this order from right to left.

[0030] As shown in Figure 2, a first oil line OL1 is provided inside the shaft 18. The first oil line OL1 extends in the left-right direction inside the shaft 18. The left end of the first oil line OL1 is bent at a right angle to the left-right direction and is located on the side surface of the first portion 18a.

[0031] The right end (first direction end) of such a shaft 18 is inserted into the first recess G1, the second recess G2, and the third recess G3 (recess G0). More specifically, the first portion 18a is inserted into the sleeve 14. The second portion 18b is inserted into the bearing 17. Thus, the bearing 17 supports the shaft 18.

[0032] When the right end of the shaft 18 is inserted into the recess G0, the left end of the first oil line OL1 can connect to the upper end of the second oil line OL2 through the hole H in the sleeve 14. More specifically, when the shaft 18 rotates, the left end of the first oil line OL1 connects to the hole H at the moment when the left end of the first oil line OL1 faces downwards. In this way, the second oil line OL2 is configured to be connectable to the first oil line OL1 by being connected to the recess G0.

[0033] The differential bearing is mounted in recess G4. This houses the differential bearing (the lubricated object) within case 12. The differential bearing is both lubricated and cooled by the oil.

[0034] The bolt 22 is attached to the case 12 so as to block the upper end of the first hole h1.

[0035] Next, the flow of oil in the power transmission device 10 will be described. The oil is contained within the case 12. The oil circulates within the case 12 due to the rotation of the gears and the shaft.

[0036] Here, most of the oil flowing to the right through the first oil line OL1 shown in Figure 2 flows into the second oil line OL2 through hole H. However, a portion of the oil flowing to the right through the first oil line OL1 passes through the gap between the sleeve 14 and the shaft 18 and the gap between the sleeve 14 and the case 12 and flows into the first hole h1.

[0037] If the amount of oil in the first hole h1 increases, there is a possibility that oil may leak from the gap between the first hole h1 and the bolt 22. Therefore, the second hole h2 connects the first hole h1 to the internal space of the case 12. This allows the oil in the first hole h1 to flow into the inside of the case 12.

[0038] The oil that flows out from the first hole h1 falls down as shown by the arrow in Figure 1. As a result, the oil reaches the boss 12a. The oil that reaches the boss 12a flows along the boss 12a and reaches the guide portion 12c. The oil that reaches the guide portion 12c flows along the guide portion 12c and reaches the groove X. The oil that reaches the groove X flows into the recess G4. In this way, the guide portion 12c guides the oil that has flowed along the boss 12a to the differential bearing, which is the object to be lubricated. As a result, the oil cools and lubricates the differential bearing.

[0039] Furthermore, due to the rotation of the gears and the shaft, oil is scattered inside the case 12. As shown in Figure 4, the scattered oil reaches the upper main surface of the rib 12b. The oil that reaches the upper main surface of the rib 12b flows along the upper main surface of the rib 12b and falls downwards and rearwards. The oil then reaches the rib 12d. Since the height of the rib 12d is low, the oil goes over the rib 12d and reaches the guide portion 12c. The oil that reaches the guide portion 12c flows along the guide portion 12c and reaches the groove X. The oil that reaches the groove X flows into the recess G4. In this way, the guide portion 12c guides the oil that has flowed along the rib 12b to the differential bearing, which is the object to be lubricated. As a result, the oil cools and lubricates the differential bearing.

[0040] [effect] The power transmission device 10 can supply oil to the differential bearing, which is the object to be lubricated. More specifically, the rib 12b is located above the recess G0 and the second hole h2. When viewed from below, the rib 12b overlaps with the recess G0 and the second hole h2. As a result, the oil that flows out from the first hole h1 flows downward and rearward along the lower main surface of the rib 12b, as shown by the arrow in Figure 1. Therefore, the oil can easily reach the differential bearing, which is located below the rib 12b. In this way, the rib 12b plays a role in guiding the oil to the differential bearing, which is the object to be lubricated. As a result, the power transmission device 10 can supply oil to the differential bearing, which is the object to be lubricated.

[0041] Furthermore, the power transmission device 10 can supply oil to the differential bearing, which is the object to be lubricated. More specifically, oil is scattered within the case 12. As shown in Figure 4, the scattered oil reaches the upper main surface of the rib 12b. The rib 12b is located above the recess G0 and the second hole h2. When viewed from below, the rib 12b overlaps with the recess G0 and the second hole h2. Therefore, the oil that reaches the upper main surface of the rib 12b flows along the upper main surface of the rib 12b and falls downwards and rearwards. The oil easily reaches the differential bearing, which is located below the rib 12b. In this way, the rib 12b plays a role in guiding the oil to the differential bearing, which is the object to be lubricated. As a result, the power transmission device 10 can supply oil to the differential bearing, which is the object to be lubricated.

[0042] Furthermore, the power transmission device 10 can reduce the probability of oil flowing into the first hole h1 through the second hole h2. More specifically, the oil scattered within the case 12 flows along the upper main surface of the rib 12b and falls in the forward-downward or rear-downward direction of the rib 12b. When viewed from below, the rib 12b overlaps with the second hole h2. Therefore, the oil scattered within the case 12 is unlikely to reach the second hole h2. As a result, the power transmission device 10 can reduce the probability of oil flowing into the first hole h1 through the second hole h2.

[0043] Furthermore, in the power transmission device 10, the guide section 12c directs the oil that has flowed along the rib 12b or boss 12a to the differential bearing, which is the object to be lubricated. This allows oil to be supplied to the differential bearing, which is the object to be lubricated.

[0044] Furthermore, the width of the guide section 12c in the front-to-back direction decreases as it goes downwards. As a result, the oil flowing through the guide section 12c collects in the groove X.

[0045] (Other embodiments) The vehicle bearing structure according to the present invention is not limited to the power transmission device 10, but can be modified within the scope of its gist.

[0046] Note that the objects to be lubricated are not limited to differential bearings. Any object that is prone to wear and any object that generates heat due to friction or other factors can be lubricated.

[0047] Note that the guide section 12c may be a rib instead of a slope.

[0048] The first hole h1 and the second oil line OL2 may be inclined with respect to the vertical. [Explanation of Symbols]

[0049] 10: Power transmission device 12: Case 12a: Boss 12b, 12d: Ribs 12c: Guide section 14: Sleeves 16: Plate 17: Bearings 18: Shaft 18a: Part 1 18b:Second part 18c: 3rd part 22: Bolt G0, G4, G5: recessed G1: First recess G2: Second recess G3: Third recess H: Hole OL1: First oil line OL2: Second oil line S0: Main surface X: Groove h1: 1st hole h2: 2nd hole

Claims

1. The power transmission device comprises a case and a shaft. The aforementioned shaft extends in the first direction, A first oil line is provided inside the shaft. The case is provided with a recess, a first hole, a second hole, a second oil line, and a rib. The first end of the shaft is inserted into the recess, The first hole extends in the vertical direction and is connected to the outside of the case and the recess. The second oil line is a hole extending in the vertical direction, aligned in a straight line with the first hole, and connected to the recess, thereby being configured to be connectable to the first oil line. The second hole connects the internal space of the case to the first hole. The rib is a projection provided on the inner circumferential surface of the case, located above the recess and the second hole, and overlapping with the second hole when viewed from below. Power transmission device.

2. The power transmission device further includes an object to be lubricated, The object to be lubricated is housed in the case, The inner circumferential surface of the aforementioned case is provided with a boss and a guide portion. The boss is a projection provided on the inner circumferential surface of the case, and, when viewed in the first direction, surrounds the recess. The guide portion includes a portion located below the rib and guides the oil that has flowed along the rib or the boss to the object to be lubricated. The power transmission device according to claim 1.

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