JP2005009680A - Balancer device for engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the infiltration of oil from an oil discharge hole of a balancer housing without using a special cover member. <P>SOLUTION: The balancer housing 17 of this balancer device 16 disposed to face an oil pan 15 below a crankshaft 20 of an engine E is provided with the oil discharge ports 45c, 46 discharging oil accumulated inside, in association with the rotation of balancer weights 18c, 19c. The oil discharge ports 45c, 46 are covered with baffle plates 47, 48 suppressing the turbulence of an oil surface of oil stored in the oil pan 15. The infiltration of oil into the balancer housing 17 from the oil discharge ports 45c, 46 can thereby be suppressed without providing the special cover for covering the oil discharge ports 45c, 46. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an engine balancer device in which a balancer housing facing an oil pan is disposed below a crankshaft.

Such engine balancer devices are known from the following Patent Documents 1 and 2, for example, Patent Document 1 discloses that the oil accumulated in the balancer housing is scraped up by a rotating balancer weight and is placed on the side of the balancer housing. What is discharged to the outside through the formed gap is described. Further, Patent Document 2 describes that the upper part of the discharge port provided for discharging blow-by gas on the upper surface of the balancer housing is covered with a cover member to prevent the discharge port from being blocked with oil. Yes.
JP 2001-140985 A Japanese Utility Model Publication No. 1-61415

  By the way, since what was described in patent document 1 is not provided with the cover member which covers the clearance gap of a balancer housing, there exists a possibility that the oil which the crankshaft jumped up in the crankcase may infiltrate into the balancer housing from the said clearance gap. . In order to prevent this, it is conceivable to cover the gap of the balancer housing with the cover member described in Patent Document 2, but this requires a special cover member, which increases the number of parts and assembly man-hours. There is a problem.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to suppress oil from entering from an oil discharge hole of a balancer housing without providing a special cover member.

  In order to achieve the above object, according to the first aspect of the present invention, in a balancer device for an engine in which a balancer housing facing an oil pan is disposed below a crankshaft, the oil level of oil stored in the oil pan is reduced. A balancer device for an engine is proposed in which at least a part of a baffle plate for suppressing rampage is extended to a position covering an opening formed in a balancer housing. According to this configuration, at least a part of the baffle plate that suppresses the oil level fluctuation of the oil stored in the oil pan is extended to cover the opening formed in the balancer housing, so that the crankshaft is lifted up. The oil can be prevented from entering the inside of the balancer housing from the opening using the existing baffle plate. Thereby, it is not necessary to provide a special cover member that covers the opening, and it is possible to contribute to the reduction of the number of parts and the number of assembling steps.

  According to the invention described in claim 2, in addition to the configuration of claim 1, the baffle plate has a plurality of cover portions respectively covering a plurality of openings, and the plurality of cover portions are interposed between the plurality of cover portions. An engine balancer device characterized by forming a notch or a hole is proposed. According to this configuration, since the notches or holes are formed between the plurality of cover portions of the baffle plate so as to cover the plurality of openings, respectively, an increase in the weight of the baffle plate can be minimized.

  According to the invention described in claim 3, in addition to the structure of claim 2, the notch or hole is provided at a position facing a balancer weight having a diameter larger than that of the journal of the balancer shaft. A featured engine balancer device is proposed. According to this configuration, since the notch portion or hole portion of the baffle plate is provided at a position facing the balancer weight of the balancer shaft, the increase in the vertical dimension of the engine due to the provision of the baffle plate can be minimized. it can.

  According to the invention described in claim 4, in addition to the configuration of claim 2 or claim 3, the position at which the baffle plate is fastened to the support member is set to the cover part rather than the notch part or the hole part. An engine balancer device characterized by the close position is proposed. According to this configuration, since the baffle plate is fastened to the support member at a position closer to the cover part than the notch part or hole part, it is possible to increase the rigidity of the cover part and suppress the occurrence of vibration.

  The lower block 14 of the embodiment corresponds to the support member of the present invention, and the drive balancer shaft 18 and the driven balancer shaft 19 of the embodiment correspond to the balancer shaft of the present invention, and the first and second journals 18a of the embodiment. , 19a; 18d, 19d correspond to the journal of the present invention, the second balancer weights 18e, 19e of the embodiment correspond to the balancer weight of the present invention, and the oil discharge ports 45a-45-45d, 46 of the embodiment Corresponding to the opening of the invention, the first to third baffle plates 47 to 49 of the embodiment correspond to the baffle plate of the present invention.

  As described above, according to the first aspect of the present invention, at least a part of the baffle plate that suppresses the oil level fluctuation of the oil stored in the oil pan is extended to form the opening formed in the balancer housing. Since it covered, it can suppress using the existing baffle plate that the oil splashed up by the crankshaft permeates into the inside of the balancer housing from the opening. Thereby, it is not necessary to provide a special cover member that covers the opening, and it is possible to contribute to the reduction of the number of parts and the number of assembling steps.

  According to the second aspect of the present invention, the notch portion or the hole portion is formed between the plurality of cover portions of the baffle plate so as to cover the plurality of openings, respectively, so that an increase in the weight of the baffle plate is minimized. be able to.

  According to the invention described in claim 3, since the notch portion or hole portion of the baffle plate is provided at a position facing the balancer weight of the balancer shaft, the size of the engine in the vertical direction increases due to the provision of the baffle plate. Can be minimized.

  According to the invention described in claim 4, since the baffle plate is fastened to the support member at a position closer to the cover portion than the notch portion or the hole portion, the rigidity of the cover portion is increased and the occurrence of vibration is suppressed. Can do.

  Embodiments of the present invention will be specifically described below based on the embodiments of the present invention illustrated in the accompanying drawings.

  1 to 12 show a first embodiment of the present invention. FIG. 1 is a front view of an engine, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. FIG. 4 is a sectional view taken along line 4-4 in FIG. 2, FIG. 5 is a sectional view taken along line 5-5 in FIG. 3, FIG. 6 is a sectional view taken along line 6-6 in FIG. 7 is a sectional view taken along line 7-7, FIG. 8 is a sectional view taken along line 8-8 in FIG. 6, FIG. 9 is a sectional view taken along line 9-9 in FIG. 11 is a sectional view taken along the line 11-11 in FIG. 6, and FIG. 12 is a sectional view taken along the line 12-12 in FIG.

  As shown in FIG. 1, the outline of the in-line four-cylinder engine E for a vehicle is configured by stacking a head cover 11, a cylinder head 12, a cylinder block 13, a lower block 14, and an oil pan 15 from above to below. The cylinder axis L is inclined to the exhaust side (left side in the figure) with respect to the vertical direction. The secondary balancer device 16 fixed to the lower surface of the lower block 14 and accommodated in the oil pan 15 includes a drive-side balancer shaft 18 and a driven balancer shaft 19 supported by a balancer housing 17. A sprocket 21 provided at the shaft end of the crankshaft 20 supported between the lower blocks 14 and a sprocket 22 provided at the shaft end of the drive-side balancer shaft 18 are connected by an endless chain 23.

  As shown in FIGS. 2 to 5, the four pistons 25 slidably fitted to the four cylinder bores 24 provided on the cylinder block 13 are respectively connected to the four pins 20 a of the crankshaft 20. It is connected via connecting rods 26. Five bearing caps 27 fitted into the lower block 14 are fastened to the lower surface of the cylinder block 13 with two bolts 28, 28, respectively, and the cylinder block 13 and the five bearing caps 27 are connected to each other. Between the five journals 20b of the crankshaft 20 are rotatably supported.

  The balancer housing 17 of the secondary balancer device 16 connects the upper housing 29 and the lower housing 30 with eleven bolts 31... 32, 32; 33, 33; 34a, 34a, 34b, 34b. A pump housing 35 is coupled to one end of the housing 30 with a plurality of bolts 36. An upper wall portion 30 b that extends to the upper surface side of the balancer housing 17 is formed at the end portion of the lower housing 30 on the pump housing 35 side, and the upper wall portion 30 b is sandwiched between the upper housing 29 and the pump housing 35. At this time, a slit-shaped opening α (FIGS. 6, 8, and 9) is formed between the upper housing 29 and the upper wall portion 30 b of the lower housing 30.

  The three bolts 31 arranged so as to sandwich the drive balancer shaft 18 and the driven balancer shaft 19 are inserted from the upper housing 29 side and fastened to the lower housing 30. The two bolts 32, 32 arranged outside the drive balancer shaft 18 and the two bolts 33, 33 arranged outside the driven balancer shaft 19 are inserted from the upper housing 29 side and are inserted into the lower housing 30. To be concluded. Two bolts 34 a and 34 a inserted into the pump housing 35 on one end side of the balancer housing 17 pass through the bearing cap 27 and are fastened to the lower surface of the cylinder block 13, and on the other end side of the balancer housing 17 Two bolts 34 b and 34 b inserted from the housing 30 side pass through the upper housing 29 and the bearing cap 27 and are fastened to the lower surface of the cylinder block 13.

  The upper housing 29 is supported on the bearing caps 27 and 27 by four mounting seats 29a through which the four bolts 34a, 34a, 34b and 34b pass, and accordingly, the upper surface of the upper housing 29 and the bearing caps 27 and 27 are supported. A gap β (see FIG. 4) is formed between the lower surface and the lower surface.

  Next, the structure of the secondary balancer device 16 will be further described based on FIGS.

  As is apparent from FIG. 8, the drive balancer shaft 18 of the secondary balancer device 16 has the sprocket 22, the first journal 18a, the drive gear 18b, the first balancer weight 18c, from one end side to the other end side. A second journal 18 d and a second balancer weight 18 e are provided, and the first and second journals 18 a and 18 d are supported so as to be sandwiched between the upper housing 29 and the lower housing 30. As is apparent from FIG. 9, the driven balancer shaft 19 of the secondary balancer device 16 has a first journal 19a, a driven gear 19b, a first balancer weight 19c, and a second journal 19d from one end side to the other end side. The second balancer weight 19e is provided, and the first and second journals 19a and 19d are supported so as to be sandwiched between the upper housing 29 and the lower housing 30.

  An oil pump 41 (see FIG. 9) is provided at one end of the driven balancer shaft 19 that protrudes into the pump housing 35. The oil pump 41 includes a known trochoid pump, and includes an inner rotor 42 fixed to the driven balancer shaft 19 and an outer rotor 43 that is rotatably supported by the pump housing 35 and meshes with the inner rotor 42. A strainer 44 positioned below the oil level O of the oil stored in the oil pan 15 is provided on the lower surface of the lower housing 30, and the strainer 44 and the suction port 41 a of the oil pump 41 are integrated with the lower surface of the lower housing 30. They are connected by the formed oil passage 30a (see FIG. 12). The strainer 44 includes a strainer element 44a that filters foreign matters in the oil, and a strainer cover 44b that covers the strainer element 44a. The discharge port 41b of the oil pump 41 is connected to the main gallery 13a (see FIGS. 3 and 4) of the cylinder block 13 through an oil passage (not shown).

  The upper housing 29 has a pair of openings 29b and 29b facing the drive gear 18b and the driven gear 19b, a pair of openings 29c and 29c facing the first balancer weights 18c and 19c, and a pair facing the second balancer weights 18e and 19e. The openings 29d and 29d are formed. By providing these openings 29b, 29b; 29c, 29c; 29d, 29d, the locus T (see FIG. 3) of the lower end of the connecting rod 26 is prevented from interfering with the upper surface of the upper housing 29. The engine E can be downsized. In addition, openings 17 a and 17 b (see FIG. 10) facing the shaft ends of the drive balancer shaft 18 and the driven balancer shaft 19 extend over the upper housing 29 and the lower housing 30 on the end surface of the balancer housing 17 opposite to the pump housing 35. Formed. The openings 17a and 17b are for machining the support portions of the first and second journals 18a and 19a; 18d and 19d of the drive balancer shaft 18 and the driven balancer shaft 19 inside the balancer housing 17, and the openings The inner diameters of 17a and 17b are slightly larger than the outer diameters of the first and second journals 18a and 19a; 18d and 19d.

  At the end of the upper housing 29 on the drive balancer shaft 18 side, four oil discharge holes 45a to 45d opened on the upper surface thereof are formed. Each of the oil discharge holes 45 a to 45 d is formed in a long hole shape extending in the axial direction of the crankshaft 20. One (or a plurality) of slit-like oil discharge holes 46 extending along the mating surfaces of the upper housing 29 and the lower housing 30 are formed at the end of the balancer housing 17 on the driven balancer shaft 19 side. The oil discharge holes 45a to 45d open in the direction of the cylinder axis L, and the oil discharge port 46 opens in a direction perpendicular to the cylinder axis L. Due to the inclination of the cylinder axis L, the balancer housing 17 is inclined such that the drive balancer shaft 18 side is lowered and the driven balancer shaft 19 side is raised. However, the oil discharge ports 45a to 45d and the driven balancer shaft on the drive balancer shaft 18 side are inclined. The oil discharge port 46 on the 19th side is disposed at a position higher than the oil level O (see FIG. 3) of the oil stored in the oil pan 15.

  A substantially rectangular first baffle plate 47 is fastened to the upper surface of the upper housing 29 on the side of the drive balancer shaft 18 by the two bolts 32, 32 connecting the upper housing 29 and the lower housing 30. A substantially rectangular second baffle plate 48 is fastened together with the two bolts 33, 33 connecting the upper housing 29 and the lower housing 30 to the upper surface of the end portion of the housing 29 on the driven balancer shaft 19 side. The number of parts and the fastening space can be reduced. Further, a U-shaped third baffle plate 49 is fixed to the lower surface of the lower block 14 with four bolts 50.

  Thus, the rotation of the crankshaft 20 is transmitted to the drive balancer shaft 18 through the sprocket 21, the endless chain 23 and the sprocket 22 by the operation of the engine E, and the rotation of the drive balancer shaft 18 is transmitted through the drive gear 18b and the driven gear 19b. To the driven balancer shaft 19. At this time, the number of teeth of the sprocket 21 of the crankshaft 20 is set to twice the number of teeth of the sprocket 22 of the drive balancer shaft 18, and the number of teeth of the drive gear 18b is set equal to the number of teeth of the driven gear 19b. Therefore, the drive balancer shaft 18 and the driven balancer shaft 19 rotate in opposite directions at a rotational speed twice that of the crankshaft 20 (see arrows A and B in FIGS. 11 and 12), and the drive balancer shaft 18 The secondary vibration of the engine E is reduced by the first and second balancer weights 18c, 19c; 18e, 19e provided on the driven balancer shaft 19.

  Since the crankshaft 20 splashes up the oil in the crankcase during the operation of the engine E, the oil tends to enter the balancer housing 17 through the openings 29b, 29b; 29c, 29c; 29d, 29d; 17a, 17b. To do. When oil enters the balancer housing 17, the drive gear 18b, the driven gear 19b, the first and second balancer weights 18c, 19c; 18e, 19e, and the like are agitated to increase the agitation resistance. Accordingly, the drive balancer shaft 18 rotating in the directions of arrows A and B in FIG. 11 and the drive gear 18b of the driven balancer shaft 19, the driven gear 19b, the first and second balancer weights 18c, 19c; 18e, 19e, etc. The oil is discharged from the oil discharge holes 45a to 45d and 46 of the balancer housing 17 to the outside and returned to the oil pan 15 to prevent the stirring resistance from increasing.

  At this time, as shown in FIGS. 10 to 12, the outer end edges of the first and second baffle plates 47 and 48 and the outer end edges of the cover portions 49a and 49b of the third baffle plate 49 are bent downward. The oil discharged from the oil discharge holes 45a to 45d and 46 can be changed in the downward direction and smoothly returned to the oil pan 15.

  Due to the first baffle plate 47 and the second baffle plate 48 fixed to the balancer housing 17 and the third baffle plate 49 fixed to the lower block 14, the oil level O of the oil stored in the oil pan 15 is ramped. Is prevented. When the splash of oil splashed with the rotation of the crankshaft 20 scatters inside the crankcase, at least a part of the first to third baffle plates 47 to 49 is an oil discharge hole of the balancer housing 17. Since the oil extends to a position covering 45a to 45d and 46, the oil splash is blocked by the first to third baffle plates 47 to 49 and enters the balancer housing 17 from the oil discharge holes 45a to 45d and 46. Can be suppressed. Thus, since the oil discharge holes 45a to 45d and 46 are covered using the existing first to third baffle plates 47, 48 and 49, a special cover for covering these oil discharge holes 45a to 45d and 46 is provided. Members are not required, and the number of parts and assembly man-hours can be reduced.

  In particular, the U-shaped third baffle plate 49 includes a plurality of cover portions 49a and 49b that cover the plurality of oil discharge ports 45d and 46, and a notch 49c is provided between the cover portions 49a and 49b. Accordingly, the weight increase of the third baffle plate 49 can be minimized by the cutout portion 49c while covering part of the oil discharge ports 45d and 46 with the cover portions 49a and 49b. In addition, two of the four bolts 50... For fixing the third baffle plate 49 to the lower block 14 are disposed closer to the cover portions 49a and 49b than the notch portion 49c. Therefore, the cover portions 49a and 49b. The rigidity can be increased to suppress vibration. The notch 49c is provided at a position facing the second balancer weights 18e, 19e having a diameter larger than that of the second journals 18d, 19d of the drive balancer shaft 18 and the driven balancer shaft 19, so that the vertical direction of the engine E is increased. The increase in the dimension of can be minimized.

  The first baffle plate 47 as a cover member covers the oil discharge ports 45a to 45c as a plurality of openings, and the third baffle plate 49 as a cover member covers the oil discharge ports 45d and 46 as a plurality of openings. That is, since the plurality of openings are respectively covered with a single cover member, the number of cover members can be reduced.

  A first baffle that covers oil discharge ports 45c and 45d provided respectively on the sides of the first balancer weight 18c and the second balancer weight 18e (in a direction orthogonal to the drive balancer shaft 18) provided across the second journal 18d. Since the plate 47 and the third baffle plate 49 are provided independently as separate bodies, the connection configuration of the first baffle plate 47 and the third baffle plate 49 becomes complicated around the second journal 18d. In addition, the enlargement of the first and third baffle plates 47 and 49 as the cover member can be suppressed.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  In the second embodiment, the first baffle plate 47 and the second baffle plate 48 of the first embodiment are integrally connected by a connecting portion 51, and the number of parts is reduced as a single baffle plate 52 having a U-shape. The shapes and functions of the first baffle plate 47 and the second baffle plate 48 are the same as those in the first embodiment.

  In the first embodiment shown in FIG. 6, the edge of the U-shaped notch 49 c of the third baffle plate 49 has a gap γ (see FIGS. 6 and 7) between the edge of the balancer housing 17. However, if the edge of the U-shaped notch 49c of the third baffle plate 49 overlaps the edge of the balancer housing 17 by a distance δ as in the second embodiment, the third baffle The oil from above the plate 49 can be prevented from entering the openings 17 a and 17 b at the end of the balancer housing 17.

  Next, a third embodiment of the present invention will be described with reference to FIG.

  In the first embodiment shown in FIG. 6, a U-shaped cutout portion 49c is formed between the pair of cover portions 49a, 49b of the third baffle plate 49. In the third embodiment, the second balancer weight 18e is formed. , 19e, a pair of holes 49d, 49d facing the pair of openings 29d, 29d are formed between the cover portions 49a, 49b. According to this embodiment, the holes 49d and 49d exhibit the same function as the notch 49c of the first embodiment, thereby reducing the weight of the third baffle plate 49 and reducing the vertical dimension of the engine E. The rigidity of the cover portions 49a and 49b can be increased by the T-shaped connecting walls 49e and 49f surrounding the hole portions 49d and 49d, and the occurrence of vibration can be more effectively suppressed.

  As mentioned above, although the Example of this invention was explained in full detail, this invention can perform a various design change in the range which does not deviate from the summary.

  For example, in the embodiment, the first and second baffle plates 47 and 48 are fixed to the balancer housing 17, and the third baffle plate 49 is fixed to the lower block 14, but their mounting positions can be changed as appropriate. .

  Moreover, the opening part of the balancer housing 17 is not limited to the oil discharge holes 45a to 45d and 46 of the embodiment, and may be an arbitrary opening part such as a breather hole.

Front view of the engine 2-2 sectional view of FIG. 3-3 sectional view of FIG. Sectional view along line 4-4 in FIG. Sectional view along line 5-5 in FIG. 6-6 arrow view of FIG. FIG. 7-7 arrow view of FIG. Sectional view taken along line 8-8 in FIG. Sectional view taken along line 9-9 in FIG. Sectional view taken along line 10-10 in FIG. 11-11 sectional view of FIG. 12-12 sectional view of FIG. The figure corresponding to the said FIG. 6 based on 2nd Example of this invention. The figure corresponding to the said FIG. 6 based on 3rd Example of this invention.

Explanation of symbols

14 Lower block (support member)
15 Oil pan 17 Balancer housing 18 Drive balancer shaft (balancer shaft)
18a First journal (journal)
18d Second journal (journal)
18e Second balancer weight (balancer weight)
19 Driven balancer shaft (balancer shaft)
19a First journal (journal)
19d Second journal (journal)
19e Second balancer weight (balancer weight)
20 Crankshaft 45a Oil outlet (opening)
45b Oil outlet (opening)
45c Oil outlet (opening)
45d Oil outlet (opening)
46 Oil outlet (opening)
47 1st baffle plate (baffle plate)
48 Second baffle plate (baffle plate)
49 3rd baffle plate (baffle plate)
49a Cover part 49b Cover part 49c Notch part 49d Hole part O Oil surface

Claims (4)

In an engine balancer device in which a balancer housing (17) facing an oil pan (15) is disposed below a crankshaft (20),
At least a part of a baffle plate (47, 48, 49) for suppressing the oil level (O) of the oil stored in the oil pan (15) from being formed in an opening (45a to 45d, 46) A balancer device for an engine, wherein the balancer device is extended to a position that covers 46).   The baffle plate (49) has a plurality of cover portions (49a, 49b) that respectively cover the plurality of openings (45a to 45d, 46), and a notch portion is provided between the plurality of cover portions (49a, 49b). The balancer device for an engine according to claim 1, characterized in that (49c) or a hole (49d) is formed.   The notch (49c) or hole (49d) is provided at a position facing the balancer weight (18e, 19e) having a larger diameter than the journal (18a, 19a; 18d, 19d) of the balancer shaft (18, 19). The balancer device for an engine according to claim 2, wherein The position at which the baffle plate (49) is fastened to the support member (14) is closer to the cover (49a, 49b) than the notch (49c) or the hole (49d). The balancer device for an engine according to claim 2 or claim 3.

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