engine

Abstract

To provide an engine including an oil passage for supplying lubrication oil and including an engine case having excellent manufacturability and assemblability.SOLUTION: In an engine gear case 10, an idle gear 40 has a gear shaft 41 that is a stationary member, a gear 42 and a gear bushing 43 that are pivotally supported by the gear shaft 41 and rotate around the gear shaft 41. The gear shaft 41 is provided with an in-shaft oil passage 413 that communicates with an engine-side oil passage provided in an engine and receives lubrication oil from the engine-side oil passage. The idle gear 40 is formed with an oil reservoir as a space surrounded by the gear shaft 41, the gear 42 and the gear bush 43, which receives lubrication oil from the in-shaft oil passage 413. Depending on the position of the gear 42 with respect to the gear shaft 41, a first notch 414 and a second notch 421 are overlapped to form an oil supply opening for scattering the lubrication oil from the oil reservoir.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to an engine equipped with an engine gear case that extracts driving force from a crankshaft of the engine. [Background technology]

[0002] In structures that mount an engine (such as vehicles and engine-mounted generators), a gear case (engine gear case) is attached to the engine, and the driving force is sometimes taken from the engine crankshaft through this engine gear case. The driving force taken from the engine gear case is used to drive an external device such as a hydraulic pump.

[0003] The input shaft of the external device is generally connected to the output gear of the engine gear case by a spline, and this spline needs to be lubricated with oil. The lubricating oil to be lubricated to the spline is sometimes supplied through an oil passage provided in an idle gear meshed with the output gear.

[0004] Patent Document 1 discloses a configuration in which oil can be added through an oil passage provided in a gear. In Patent Document 1, a through hole serving as an oil passage is provided in a gear and a gear shaft (supporting the gear), and when the through hole of the gear and the through hole of the gear shaft are aligned, the oil passages communicate with each other, and lubricating oil passing through the oil passage splashes, allowing oil to be added. In the oil passage of Patent Document 1, at least the through hole on the gear side is formed as a fine hole in order to appropriately adjust the amount of lubricating oil added (suppressing excessive oil addition). In conventional engine gear cases, oil is added to the splines by a configuration similar to that of Patent Document 1 (a configuration in which a through hole serving as an oil passage is provided in an idle gear and an idle gear shaft). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-191432 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the conventional configuration, when forming small holes in the gear to serve as oil passages, there is a concern that tools may break, which makes manufacturability poor. In addition, a gear bush that is press-fitted into the gear is usually provided between the gear and the gear shaft. In this case, a through hole that serves as an oil passage is also formed in the gear bush, but it is necessary to position the through hole of the gear and the through hole of the gear bush before press-fitting, which also causes a problem of poor assembly.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an engine having an engine gear case that is equipped with an oil passage for supplying lubricating oil and has excellent manufacturability and assembly properties. [Means for solving the problem]

[0008] In order to solve the above problems, the engine of the present invention is an engine equipped with an engine gear case that extracts driving force from a crankshaft, the engine gear case comprising: a lubrication section to which lubricating oil is injected; and an oil-passage gear having an internal gear oil passage for splashing the lubricating oil injected into the lubrication section, the oil-passage gear having a fixed shaft member and a rotating gear member journaled by the fixed shaft member and rotating around the fixed shaft member, the fixed shaft member being provided with an internal shaft oil passage that communicates with an engine-side oil passage provided in the engine, an oil reservoir portion that receives a supply of lubricating oil from the internal shaft oil passage is formed as a space surrounded by the fixed shaft member and the rotating gear member, and an oil injection opening for splashing lubricating oil from the oil reservoir portion is formed depending on the position of the rotating gear member relative to the fixed shaft member.

[0009] According to the above configuration, the oil reservoir is formed as a space surrounded by the fixed shaft member and the rotating gear member in the oil passage gear, and the lubricating oil can be scattered from the oil reservoir. Therefore, in the oil passage gear, it is not necessary to form an oil passage by a small hole inside the rotating gear member, and it is easy to process each component of the oil passage gear, and it is possible to improve manufacturability.

[0010] The engine may be configured so that an inner circumferential surface of the rotary gear member has a communication groove portion that communicates between the fixed shaft member and the oil reservoir portion.

[0011] According to the above configuration, the provision of the communicating groove portion makes it possible to shorten the oil passage within the shaft, thereby improving the workability of the fixed shaft member.

[0012] In addition, in the above engine, the communicating groove portion can be configured to include a first groove provided in a circular ring shape opposite the oil passage outlet of the shaft oil passage, and a second groove communicating with the first groove and provided toward the oil reservoir portion.

[0013] According to the above configuration, the lubricating oil can be smoothly supplied from the oil passage in the shaft toward the oil reservoir.

[0014] The engine may be configured such that a first groove-shaped notch portion is formed in the fixed shaft member and a second groove-shaped notch portion is formed in the rotating gear member, and the oil opening is created when the first notch portion and the second notch portion overlap due to rotation of the rotating gear member.

[0015] According to the above configuration, the groove-shaped first cutout portion and second cutout portion can be easily machined into the fixed shaft member and the rotating gear member, thereby improving manufacturability.

[0016] Also, in the engine, the first cutout portion and the second cutout portion may have an inclined portion inclined with respect to the axial direction and the radial direction of the oil passage gear.

[0017] According to the above configuration, it is easy to design the lubricating portion so that the lubricating oil is supplied through a desired route. Effect of the Invention

[0018] The engine of the present invention forms an oil reservoir as a space surrounded by a fixed shaft member and a rotating gear member in an oil-passage gear in an engine gear case, and by scattering lubricating oil from this oil reservoir, it becomes easier to process each component of the oil-passage gear, thereby improving manufacturability. [Brief description of the drawings]

[0019] [Figure 1] FIG. 2 is a front view of an engine gear case, showing one embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] This is a front view of the engine gear case, with the FW housing removed so that the internal gear arrangement can be seen. [Figure 4] FIG. [Diagram 5] 1 shows only the gear shaft of the idle gear, where (a) is a perspective view, (b) is a rear view, and (c) is a cross-sectional view taken along line AA of (b). [Figure 6] 1A shows the gear and gear bush of an idle gear, where (a) is a perspective view, (b) is a front view, (c) is a BB cross-sectional view of (b), and (d) is a CC cross-sectional view of (b). [Figure 7] 4 is an enlarged cross-sectional view of an idle gear, where (a) shows the state in which the second notch portion and the first notch portion overlap, and (b) and (c) show the state in which the second notch portion and the first notch portion do not overlap. [Figure 8] FIG. 11 is a cross-sectional view showing an oil supply path along which lubricating oil flows along the back surface of the FW housing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 is a front view of an engine gear case 10 provided in an engine according to this embodiment. Fig. 2 is a rear view of the engine gear case 10. The engine gear case 10 is attached to an engine body (not shown) and extracts driving force from a crankshaft of the engine body. Here, the side facing the engine body is the rear side of the engine gear case 10, and the side opposite to the side facing the engine body is the front side of the engine gear case 10. The configuration of the engine body is publicly known, so a detailed description will be omitted here.

[0021] As shown in Fig. 1, the front side of the engine gear case 10 is covered with a FW (flywheel) housing 11. A crankshaft 50 of the engine body is connected to the rear side of the engine gear case 10, and a spline hole 30a is provided for connecting an input shaft (not shown) of an external device (e.g., a hydraulic pump) that receives output from the engine gear case 10. That is, the input shaft of the external device is a spline shaft, and the external device can receive output from the engine gear case 10 by spline-connecting the spline shaft to the spline hole 30a. Strictly speaking, the crankshaft 50 is a member on the engine body side and is not a component of the engine gear case 10, but Fig. 1 illustrates the crankshaft 50 so that the connection relationship between the engine gear case 10 and the engine body can be understood.

[0022] 3 is a front view of the engine gear case 10 with the FW housing 11 removed so that the internal gear arrangement can be seen. As shown in FIG. 3, at least an input gear 20, an output gear 30, and an idle gear 40 are provided in the engine gear case 10. The input gear 20 is connected to the crankshaft 50 and is a gear to which the rotation of the crankshaft 50 is input. The output gear 30 is a gear for outputting a driving force from the engine gear case 10 to an external device, and is provided with the above-mentioned spline hole 30a. The idle gear 40 is a gear disposed between the input gear 20 and the output gear 30 and transmits a driving force from the input gear 20 to the output gear 30.

[0023] In the engine gear case 10, the splined shaft of the external device and the splined hole 30a of the output gear 30 are splined together, so lubricating oil needs to be supplied to the splined hole 30a. The engine gear case 10 has an oil passage (intra-gear oil passage) formed in the idle gear 40, and oil can be supplied to the splined hole 30a through this intra-gear oil passage. The main feature of the present invention is the configuration of the intra-gear oil passage formed in the idle gear 40, and this feature will be described in detail below. In this embodiment, the splined hole 30a corresponds to the lubricating portion described in the claims, and the idle gear 40 corresponds to the gear with an oil passage.

[0024] FIG. 4 is a cross-sectional view of the idle gear 40. As shown in FIG. 4, the idle gear 40 is composed of three members, a gear shaft 41, a gear 42, and a gear bush 43. The gear shaft 41 is fixed to the engine body by a bolt or the like when the engine gear case 10 is attached to the engine, and is a fixed member that does not rotate by itself. The gear 42 is an annular gear member that rotates around the gear shaft 41. The gear bush 43 is disposed between the gear shaft 41 and the gear 42, is press-fitted into the gear 42, and rotates integrally with the gear 42. In this embodiment, the gear shaft 41 corresponds to a fixed shaft member described in the claims, and the gear 42 and the gear bush 43 correspond to rotating gear members.

[0025] Fig. 5 shows only the gear shaft 41, where (a) is a perspective view, (b) is a rear view, and (c) is a cross-sectional view taken along line AA of (b). As shown in Fig. 5, the gear shaft 41 has a shaft portion 411 that supports the gear 42 (and the gear bush 43), and a flange portion 412 formed on the front side of the shaft portion 411. The flange portion 412 contacts the gear main surface on the front side of the gear 42. The gear 42 rotates while the gear main surface on the front side slides against the flange portion 412 (see Fig. 4).

[0026] An in-shaft oil passage 413 is formed in the shaft portion 411 as a through hole passing from the back surface (end surface) to the side surface (outer circumferential surface) of the shaft portion 411. The in-shaft oil passage 413 is an oil passage that communicates with a circulation oil passage (engine side oil passage) in the cylinder block of the engine body when the engine gear case 10 is attached to the engine, and receives a supply of lubricating oil from the engine side oil passage. For this reason, a communication port 12 (see FIG. 2) is provided on the back surface of the engine gear case 10 for communicating the in-shaft oil passage 413 with the engine side oil passage.

[0027] The flange portion 412 is provided with one groove-shaped first cutout portion 414. The first cutout portion 414 is formed in the main surface on the back side of the flange portion 412, and opens the outer circumferential surface of the flange portion 412 (the first cutout portion 414 is formed so as to cut out a part of the outer circumferential surface of the flange portion 412). Also, the inner circumferential end portion of the first cutout portion 414 is positioned so as not to reach the inner circumferential surface of the gear 42 in the radial direction of the idle gear 40 (see FIG. 7(b)).

[0028] 6 shows the gear 42 and the gear bush 43, where (a) is a perspective view, (b) is a front view, (c) is a BB cross-sectional view of (b), and (d) is a CC cross-sectional view of (b). As shown in FIG. 6, the gear 42, which is an annular gear, has the gear bush 43 pressed into its inside, and rotates while the outer circumferential surface of the shaft portion 411 of the gear shaft 41 and the inner circumferential surface of the gear bush 43 rub against each other. In addition, the front end surface of the gear bush 43 is located lower than the front main gear surface of the gear 42. In other words, the front end surface of the gear bush 43 is arranged not to contact the main surface of the flange portion 412 on the back side.

[0029] The gear 42 is provided with at least one (two in this example) groove-shaped second cutout portion 421. The second cutout portion 421 is formed so as to open the inner circumferential surface on the front side of the gear 42 (so as to cut out a part of the inner side surface of the gear 42). In addition, the outer circumferential end portion of the second cutout portion 421 is positioned so as not to reach the outer circumferential surface of the flange portion 412 of the gear shaft 41 in the radial direction of the idle gear 40 (see FIG. 7(c)).

[0030] A first groove 431 and a second groove 432 are formed on the inner peripheral surface of the gear bush 43. The first groove 431 is a groove portion formed in an annular shape along the circumferential direction on the inner peripheral surface of the gear bush 43. The first groove 431 is formed at a position facing an opening (oil passage outlet of the shaft oil passage 413) on the shaft side surface side of the shaft portion 411 in the axial direction of the idle gear 40. The second groove 432 is a linear groove portion extending from a part of the first groove 431 toward the front side along the axial direction. However, the second groove 432 does not need to be completely parallel to the axial direction of the idle gear 40, and may have an inclination with respect to the axial direction as shown in FIG. 6(d).

[0031] It is preferable that the outlet side end (front side end) of the second groove 432 is positioned with respect to the second cutout portion 421 of the gear 42. In the example of Fig. 6, the gear 42 and the gear bush 43 have two pairs of the second cutout portion 421 and the second groove 432, but there may be one pair or three or more pairs. When there are a plurality of pairs of the second cutout portion 421 and the second groove 432, it is preferable that they are arranged at equal angular intervals along the circumferential direction of the idle gear 40.

[0032] The in-gear oil passage formed in the idle gear 40 includes the in-shaft oil passage 413 and the first cutout portion 414 in the gear 42, the first groove 431 and the second groove 432 in the gear bushing 43, and the second cutout portion 421 in the gear 42. More specifically, the in-gear oil passage is formed in the order of the in-shaft oil passage 413, the first groove 431, the second groove 432, the second cutout portion 421, and the first cutout portion 414.

[0033] This gear oil passage is not always connected to supply oil, but is connected temporarily to supply oil intermittently during the rotation of the gear 42 and the gear bush 43. The oil supply action in the gear oil passage will be described below with reference to FIG.

[0034] First, in the gear oil passage, the first groove 431, the second groove 432, and the second cutout portion 421 are always in communication with the shaft oil passage 413, and this portion is always filled with lubricating oil. Furthermore, on the front side of the idle gear 40, the end face of the gear bush 43 is positioned lower than the gear main surface of the gear 42, so that an annular space is surrounded by the upper end face of the gear bush 43, the inner peripheral surface of the gear 42, and the gear shaft 41 (the outer peripheral surface of the shaft portion 411 and the rear side main surface of the flange portion 412), and this space serves as an oil reservoir portion 44 (see FIG. 7(a)) that temporarily stores the lubricating oil. That is, in the idle gear 40, the oil reservoir portion 44 is formed as a space surrounded by the gear shaft 41, the gear 42, and the gear bush 43.

[0035] The first groove 431 and the second groove 432 are formed as a communicating groove portion that communicates between the in-shaft oil passage 413 and the oil reservoir 44. In the idle gear 40, the formation of the communicating groove portion eliminates the need to directly connect the in-shaft oil passage 413 and the oil reservoir 44, and the in-shaft oil passage 413 in the gear shaft 41 can be shortened. As a result, the communicating groove portion also has the effect of improving the workability of the gear shaft 41.

[0036] 7(a) is an enlarged cross-sectional view of the idle gear 40 in a state where the second cutout portion 421 and the first cutout portion 414 overlap. At this time, an opening (oil injection opening) is created at the overlapping portion of the second cutout portion 421 and the first cutout portion 414, and the lubricating oil can be splashed from the oil reservoir portion 44.

[0037] When the second groove 432 is provided with an inclination with respect to the axial direction of the idle gear 40, the inlet side of the oil passage (the side connected to the first groove 431) is inclined to be located upstream in the rotation direction of the gear 42 (the direction of the arrow R shown in FIG. 6(a)) and the outlet side of the oil passage (the side connected to the second notch portion 421) is inclined to be located downstream in the rotation direction. In this case, the rotational force of the gear 42 and the gear bush 43 can apply hydraulic pressure to the lubricating oil in the second groove 432 in the scattering direction.

[0038] 7(b) and (c) are enlarged cross-sectional views of the idle gear 40 in a state in which the second cutout portion 421 does not overlap with the first cutout portion 414. At this time, no opening is formed between the second cutout portion 421 and the first cutout portion 414, and lubricating oil cannot be scattered from the oil reservoir portion 44.

[0039] In this way, the gear internal oil passage in the idle gear 40 can scatter the lubricating oil from the oil reservoir 44 only when the second notch 421 and the first notch 414 overlap during rotation of the gear 42 and the gear bush 43. In addition, when the lubricating oil is scattered, the opening area generated at the overlapping portion of the second notch 421 and the first notch 414 can be easily adjusted by the shapes of the second notch 421 and the first notch 414. In other words, the opening at the overlapping portion of the second notch 421 and the first notch 414 can easily be made narrow in area, and the amount of lubricating oil poured can be appropriately adjusted (excessive pouring of oil can be suppressed).

[0040] In the above-mentioned gear oil passage, the oil reservoir 44 is formed as a space surrounded by each member (gear shaft 41, gear 42, and gear bush 43) in the idle gear 40. Furthermore, the oil passage for supplying the lubricating oil from the shaft oil passage 413 to the oil reservoir 44 is formed by a groove formed on the surface of each member in the idle gear 40. Therefore, in the idle gear 40, an oil passage by a fine hole is not formed, and the processing of each member of the idle gear 40 is easy, so the manufacturability of the idle gear 40 is not deteriorated. Note that the shaft oil passage 413 is formed as a through hole rather than a groove in the gear shaft 41, but the shaft oil passage 413 does not have a function of adjusting the amount of lubricating oil scattering, and the shaft oil passage 413 does not need to be a fine hole. Therefore, the shaft oil passage 413 does not deteriorate the manufacturability of the gear shaft 41.

[0041] In the idle gear 40, when the gear bush 43 is press-fitted into the gear 42, it is preferable that the second groove 432 is positioned relative to the second cutout portion 421, and since the second groove 432 and the second cutout portion 421 are formed on the surface of the member, the positioning is easy. In other words, the press-fitting of the gear bush 43 into the gear 42 does not deteriorate the assembly of the idle gear 40. Note that even if the second groove 432 is not accurately positioned relative to the second cutout portion 421, as long as the second groove 432 communicates with the oil reservoir portion 44, the above-mentioned oiling operation can be performed in the idle gear 40.

[0042] The lubricating oil scattered from the idle gear 40 may be directly supplied to the spline hole 30a of the output gear 30 (the lubricating oil is scattered toward the spline connection portion), or may be indirectly supplied. In reality, it is difficult in terms of design to directly scatter the lubricating oil from the idle gear 40 to the spline hole 30a, and therefore, in this embodiment, a configuration in which the lubricating oil is indirectly supplied by utilizing the FW housing 11 is exemplified.

[0043] As described above, the oil passage in the gear of the idle gear 40 communicates with the second notch portion 421 when the first notch portion 414 overlaps with the second notch portion 421 (generating an oil supply opening), and the lubricating oil is scattered. The direction of the lubricating oil scattering at this time depends on the position of the first notch portion 414 formed in the gear shaft 41, which is the fixed member. In this embodiment, the direction of the lubricating oil scattering from the oil supply opening is the direction of the arrow D1 in FIG. 3. However, the arrow D1 direction is a direction toward the outer periphery as a circumferential component of the idle gear 40 as shown in the figure, but is a direction toward the FW housing 11 side (front side) as an axial component of the idle gear 40. That is, the direction of the lubricating oil scattering has an inclination with respect to both the axial direction and the radial direction of the idle gear 40. To achieve this scattering, the first notch portion 414 and the second notch portion 421 have inclined portions that are inclined with respect to the axial and radial directions of the idle gear 40. Specifically, as shown in Fig. 7(a), the first notch portion 414 is an inclined portion throughout, and the second notch portion 421 has an inclined portion at the end portion on the outer circumferential side in the radial direction. This allows the lubricating oil that has passed through the oil supply opening to be scattered at an angle along the inclined portions of the first notch portion 414 and the second notch portion 421.

[0044] In this way, the lubricating oil scattered in a predetermined direction from the idle gear 40 first adheres to the back surface of the FW housing 11 and reaches the spline hole 30a, which is the target of lubrication, by flowing along the back surface of the FW housing 11. At this time, the path of the lubricating oil flowing along the back surface of the FW housing 11 is the direction of arrow D2 in FIG.

[0045] 8 is a cross-sectional view showing an oil supply path along which the lubricating oil flows along the back surface of the FW housing 11. It is preferable that an oil supply path (a path formed by projections and recesses) is formed on the back surface of the FW housing 11 so that the lubricating oil can reliably reach the spline connection points.

[0046] The embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present invention is not interpreted solely by the above-described embodiments, but is defined by the claims. Also, all modifications within the scope and meaning equivalent to the claims are included. [Explanation of symbols]

[0047] 10 Engine gear case 11 FW Housing 12 Communication port 20 Input gear 30 Output gear 30a Spline hole (lubrication part) 40 Idle gear (gear with oil passage) 41 Gear shaft (fixed shaft member) 411 Shaft section 412 Flange part 413 Shaft oil passage 414 1st notch 42 Gears (rotating gear components) 421 2nd notch 43 Gear bush (rotating gear component) 431 First groove (connecting groove) 432 Second groove (connecting groove) 44 Oil Reservoir 50 Crankshaft

Claims

1. An engine equipped with an engine gear case that extracts driving force from a crankshaft, The engine gear case includes: a lubrication section where lubricating oil is injected; and a gear having an oil passage therein for scattering the lubricating oil injected into the lubricating portion, the oil passage gear includes a fixed shaft member and a rotating gear member journalled by the fixed shaft member and rotating around the fixed shaft member; the fixed shaft member is provided with an in-shaft oil passage communicating with an engine-side oil passage provided in the engine, an oil injection opening is formed which communicates with the oil passage within the gear and splashes lubricating oil when the first notch portion and the second notch portion overlap due to rotation of the rotating gear member.

2. 2. The engine of claim 1, an oil reservoir portion that receives a supply of lubricating oil from the shaft internal oil passage is formed as a space surrounded by the fixed shaft member and the rotary gear member, an oil reservoir portion and a communication groove portion, the communication groove portion being provided on an inner peripheral surface of the rotating gear member, the communication groove portion providing communication between the fixed shaft member and the oil reservoir portion;

3. 3. The engine of claim 2, The engine is characterized in that the communicating groove portion includes a first groove provided in an annular shape facing an oil passage outlet of the shaft oil passage, and a second groove communicating with the first groove and provided toward the oil reservoir portion.

4. An engine according to any one of claims 1 to 3, The engine, wherein the first cutout portion and the second cutout portion have inclined portions inclined with respect to the axial direction and radial direction of the oil passage gear.

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