DE102013222512B4 - Timing circuit cover structure for an internal combustion engine - Google Patents

Abstract

A timing harness covering structure for an internal combustion engine, wherein the timing harness covering structure is adapted to be fixed to a side of an engine body (1) of an internal combustion engine (E) and to cover a timing transmission mechanism (T) of the internal combustion engine (E), the timing harness covering structure comprising: a peripheral portion (30) having a plurality of fixing portions (31) for being fixed to the engine body (1); and a plate-shaped front side portion (32), which is connected to the peripheral portion (30) and which is adapted to cover the timing transmission mechanism (T), wherein an insertion hole (34) for inserting a rotating shaft (6) in the front side portion (32) is formed, a periphery of the insertion hole (34) is formed thicker than the front side portion (32), and a reinforcing rib group (R) is integrally provided with one of an inner surface and an outer surface of the front side portion (32) to the insertion hole (34 ), characterized in that the reinforcing rib group (R) comprises a plurality of linear tangential ribs (40) provided like tangential lines in tangential directions of the insertion hole (34) at intervals in a peripheral direction of the insertion hole (34); and the linear tangential ribs (40) have a projection portion in d overlapping the periphery of the insertion hole (34) and forming part of the projection portion, the plurality of linear tangential ribs (40) comprising a plurality of tangential rib pairs (A, B), in each of which tangential ribs symmetrical to each other with respect to Center (CE) of the insertion hole (34) are provided and intersect each other.

Description

Technical part

The present invention relates to a timing line cover structure provided on one side of an engine body of an internal combustion engine and covering a timing transmission mechanism of the internal combustion engine, particularly a timing train cover structure having improved rigidity in a periphery of an insertion hole for inserting a rotational shaft.

State of the art

In a conventional four-stroke internal combustion engine, a crankshaft and a valve camshaft for driving a valve mechanism are operatively connected by a timing transmission mechanism. A rotation of the crankshaft is transmitted to the valve camshaft at a speed reduction ratio of 1/2. The timing transmission mechanism is covered with a timing train cover provided on one side of an engine body of the internal combustion engine.

Here, since rotary shafts such as a crankshaft or the like are inserted through the timing belt cover, the timing belt cover has a problem that the rotational vibration of the rotary shafts is transmitted to a cover surface of the timing belt cover as a diaphragm vibration and causes noise radiation, causing a vibration noise.

In this connection, technical means were already known, by which the diaphragm vibration is damped and the vibration noise is reduced. For example, in the technical means of Patent Document 1 (Japanese Utility Model, Registration No. JP 2 526 040 Y2 A diaphragm vibration is suppressed by providing multiple ribs radially extending on an inner surface of a transmission case, the transmission case covering a timing string, from a bolt fixed to a cylinder block of an engine body for vibration damping to portions of the body suitable for fitting mounting bolts Transmission housing, so that the vibration caused by the operation of an internal combustion engine noise is reduced.

However, the technical means of Patent Document 1 have a problem that an effect of reducing diaphragm vibration is insufficient because regions of regions divided by the radially extending ribs are large. To solve this problem, it is conceivable that the number of radially extending ribs is increased or the thickness of the radially extending ribs is increased. However, in such a case, other problems arise, such as increasing the weight of the timing harness cover itself and increasing the cost by so much.

A Taktstrangabdeckungsstruktur according to the preamble of claim 1 is known from JP 2002-339759 A known.

WO 2010/053460 A1 discloses a high-pressure pump bearing member of an internal combustion engine, comprising a wall having an insertion hole for inserting a rotating shaft in a front side portion, and a reinforcing rib group integrally provided with one of an inner surface and an outer surface of the front side portion, the reinforcing rib group having a plurality of linear tangential Includes ribs provided like tangential lines in tangential directions of the insertion hole at intervals in a peripheral direction of the insertion hole, and the linear tangential ribs overlap a projection portion in the periphery of the insertion hole and form part of the projection portion.

Brief description of the invention

Problem to be solved by the invention

The object of the present invention is to provide a new timing harness cover structure which can greatly reduce diaphragm vibration generated in a periphery of an insertion hole for a timing shaft cover rotation shaft.

Means of solving the problems

In order to achieve the object, according to the invention described in claim 1, there is provided a timing line cover structure for an internal combustion engine, wherein the timing line cover structure is adapted to be fixed to one side of an engine body of an internal combustion engine and to cover a timing transmission mechanism of the internal combustion engine, the timing line cover structure comprising: a peripheral portion having a plurality of attachment portions to be attached to the engine body; and a plate-shaped front side portion which is connected to the peripheral portion and which is adapted to cover the timing transmission mechanism, wherein an insertion hole for inserting a rotation shaft is formed in the front side portion, a periphery of the insertion hole is made thicker than the front side portion, a reinforcing rib group is integrally provided with one of an inner surface and an outer surface of the front side portion to surround the insertion hole, the reinforcing rib group includes a plurality of linear tangential ribs which are like tangential lines in FIG tangential directions of the insertion hole are provided at intervals in a peripheral direction of the insertion hole, and the linear tangential ribs overlap a protrusion portion in the periphery of the insertion hole and form part of the protrusion portion, the plurality of linear tangential ribs comprising a plurality of tangential pair of ribs in each of these tangential ribs are provided symmetrically with each other with respect to a center of the insertion hole and intersect each other.

According to claim 2 it can be provided that the tangential rib pairs are provided over an entire periphery of the insertion hole at each uniformly predetermined angle.

According to claim 3 it can be provided that at least some of the plurality of linear tangential ribs are connected to the corresponding fastening portions.

According to claim 4, it may be provided that the front side portion is provided with an annular rib which surrounds the periphery of the insertion hole and crosses the plurality of linear tangential ribs.

According to claim 5 it can be provided that the annular rib crosses tangential ribs which intersect each other, from the plurality of linear tangential ribs, at crossing points of the tangential ribs.

According to claim 6, it may be provided that the plurality of linear tangential ribs and the annular rib are provided on the inner surface of the front side portion, a plurality of extending portions having free ends to be in contact with the engine body at the inner surface is provided, and at least one of the extending portions is provided on the annular rib.

Effects of the invention

According to the invention of any one of the claims, the periphery of the insertion hole of the timing harness cover, which has high rigidity and through which the rotational shaft is inserted, is finely divided by the reinforcing rib group, so that the front side portion having low rigidity around the insertion hole in one strong extent. In addition, the reinforcing rib group has line contact with the insertion hole, which has high rigidity. Thus, without an excessive increase in the number of ribs, the periphery of the insertion hole can be strengthened to effectively reduce the membrane vibrations generated in the periphery of the insertion hole and also to suppress an increase in weight by the reinforcing rib group.

In addition, according to the inventions of claims 1 and 2, the multiple linear tangential ribs are provided symmetrically with respect to the center of the insertion hole and intersect each other. Thus, a rigidity of the periphery of the insertion hole is uniformly increased, so that the diaphragm vibration generated in the periphery of the insertion hole can be more effectively reduced.

In addition, according to the invention of claim 3, one end of the linear tangential rib is connected to the insertion hole having high rigidity, and its other end is connected to the attachment portion which has high rigidity. Thus, the rigidity of the rib is greatly increased, and moreover, rigidity of another rib crossing with the rib may be increased.

In addition, according to the invention of claims 4 and 5, the annular rib divides the linear tangential ribs in a longitudinal direction thereof so that the front side portion is more finely divided. Moreover, the linear tangential ribs may be connected to each other in a peripheral direction by the annular rib. Thus, the rigidity of the periphery of the insertion hole is further increased, and the diaphragm vibration generated in the periphery of the insertion hole can be more effectively reduced.

Moreover, according to the invention of claim 6, the extending portions having free ends to be in contact with the engine body are provided on the inner surface of the front side portion of the timing harness cover, and the extending portions are provided on the annular rib. Thus, a rigidity of the front side portion is increased, and a rigidity of the annular rib is also increased. For this reason, an effect of reducing the diaphragm vibration generated in the periphery of the insertion hole can be further enhanced.

Brief description of the figures

1 FIG. 12 is an end view, viewed in the direction of a crankshaft, of an engine body of an internal combustion engine equipped with a timing harness cover structure of the present invention.

2 is a partial sectional side view of the engine body taken along the line 2-2 1 ,

3 is a partially enlarged view taken along the line 3-3 2 the timing harness cover viewed from an interior area thereof.

4 is an enlarged sectional view taken along line 4-4 of 3 ,

5 Fig. 10 is a schematic diagram of a reinforcing rib group.

Method for carrying out the invention

Hereinafter, an embodiment of the present invention will be specifically described with reference to the accompanying drawings.

This embodiment shows a case where a timing harness covering structure of the present invention is applied to an OHV-type four-cycle, multi-cylinder internal combustion engine E of an automobile.

In the following description, an up-down direction, a left-right direction, and an inside-outside direction are those directions that are related to an engine body 1 in 1 are defined.

As in 1 and 2 shown, forms the engine body 1 a main portion of the internal combustion engine E, comprising: a cylinder block 2 which has a plurality of cylinders provided in a row and in each of which a piston 13 slidably inserted; and a cylinder head 3 which is on a top surface of the cylinder block 2 is fixed and in which a valve mechanism V is provided. A head cover 4 is on an upper surface of the cylinder head 3 fixed. An oil pan 5 is connected to a lower surface of a portion of a crankcase, which is located in a lower portion of the cylinder block 2 located. A crankshaft 6 is rotatably supported by the portion of the crankcase and a bearing cap 16 is fixed to a lower surface of the portion of the crankcase. In addition, there is a pair of valve camshafts 7 for driving a valve mechanism V rotatably in the cylinder head 3 supported and the valve mechanism V is with the head cover 4 covered.

The crankshaft 6 and the valve camshafts 7 are operatively connected together by a timing transmission mechanism T. The timing transmission mechanism T includes a drive sprocket 8th , which is at an outer end of the crankshaft 6 moored, a double Umlenkkettenrad 11 which passes through the cylinder block 2 is rotatably supported, a driven sprocket 9 , which at an outer end of a valve camshaft 7 moored on an inlet side, an endless chain 12 around the drive sprocket 8th and a sprocket of the double sprocket wheel 11 is winding and an endless chain 10 which around the other sprocket of the double Umlenkkettenrads 11 and the driven sprocket 9 is winding. A rotation of the crankshaft 6 gets to the valve camshafts 7 transmitted by the timing transmission mechanism T at a speed reduction ratio of 1/2.

It should also be noted that the camshaft 7 on the inlet side and the camshaft 7 ' on the exhaust side are connected to each other by a gear and that the double Umlenkkettenrad 11 is provided to drive a fuel pump (not shown).

The timing transmission mechanism T is out of a side surface (a surface perpendicular to the crankshaft 6 ) of the engine body 1 provided and is covered with a Taktststrangabdeckung C, which is fixed to the one side surface.

The timing harness cover C is made of metal and is on one side on surfaces of the cylinder block 2 and the cylinder head 3 moored while bridging an intermediate mating surface.

The timing harness cover C includes a peripheral portion 30 , which with multiple mounting portions 31 is provided to the engine body 1 to be moored, and a plate-shaped front side portion 32 , which with the peripheral portion 30 which is substantially parallel to the one side surface of the engine body 1 is aligned and which covers the timing transmission mechanism T. The peripheral part 30 is a portion extending from the front panel portion 32 towards the engine body 1 too crooked. In the multiple attachment sections 31 are protrusion holes for inserting connecting bolts 15 educated. The multiple mounting sections 31 are on the one side of the motor body 1 through the connecting bolts 15 attached, which are inserted in the projection holes.

In a lower portion of the front panel section 32 the timing harness cover C is a round insertion hole 34 for inserting an end portion of the crankshaft 6 educated. The insertion hole 34 is a protrusion hole, and an outer peripheral portion of the protrusion hole is formed to have a predetermined width in a radial direction over an entire periphery of the insertion hole 34 and that it has a greater thickness than the front side portion 32 the Taktststrangabdeckung C has. An oil seal 35 is between an inner peripheral surface of the insertion hole 34 and an outer peripheral surface of the crankshaft 6 provided to seal a space therebetween in an oil-tight manner.

As in 3 has a periphery of the insertion hole 34 an increased rigidity, as these by a reinforcing rib group R, which integral with an inner surface of the front side portion 32 is formed in a protruding manner is reinforced.

A drive power, which is generated when the chains 12 and 10 of the timing transmission mechanism T are caused by air transmission or the like, a diaphragm surface vibration of the timing harness cover C, and the timing harness cover C itself generates noise. However, a natural frequency of the timing string cover C is increased as compared with a usual range by the reinforcing rib group R according to the present invention, so that resonance of the timing string cover C can be prevented.

A membrane vibration occurring in the periphery of the insertion hole 34 by a torsional vibration of the crankshaft 6 or the like is generated is reduced.

Hereinafter, a specific structure of the reinforcing rib group R will be described.

As in 3 and 5 As shown, the reinforcing rib group R includes multiple pairs of linear tangential ribs 40 which are in the periphery of the insertion hole 34 , ie the projection hole, are present and in tangential directions of the insertion hole 34 at intervals in the peripheral direction of the insertion hole 34 extend, with the linear tangential ribs 40 to cross each other in each of the pairs. In addition to the linear tangential ribs 40 is the front part area 32 with an annular rib 50 which has an outer periphery of the insertion hole 34 surrounds, with a gap between them.

In 3 and 5 are the multiple pairs of linear tangential ribs 40 configured from 12 pairs of first to twelfth tangential rib pairs A and 12 pairs of first to twelfth tangential rib pairs B, each formed as follows. The 12 pairs of first to twelfth tangential rib pairs A are along the outer peripheral surface of the insertion hole 34 formed at substantially equal intervals. Each of the pairs includes two tangential ribs Aa, Ab extending in the tangential directions of the insertion hole 34 extend and have an included angle of substantially 90 °. A crossing point of each of these tangential rib pairs A is outside the insertion hole 34 ,

In addition, the 12 pairs of first to twelfth tangential rib pairs B are along the outer peripheral surface of the insertion hole 34 formed at substantially equal intervals. Each of the pairs includes two tangential ribs Ba, Bb, which are in the tangential directions of the insertion hole 34 extend and which have an included angle of substantially 30 °. Each intersection point of the first to twelfth tangential pair of ribs A and the corresponding intersection of the first to twelfth tangential pair of ribs B are both on a line extending radially through a center CE of the insertion hole 34 extends. The crossing points of the first to twelfth tangential rib pairs B are outside the crossing points of the first to twelfth tangential rib pairs A. In addition, the crossing points of the first to twelfth tangential rib pairs B are to the front side portion 32 except that some of the first through twelfth tangential rib pairs B are connected to the front panel portion 32 are connected before the crossing points.

In addition, both the first to twelfth tangential rib pairs A and the first to twelfth tangential rib pairs B are symmetrical with respect to the center CE of the insertion hole 34 provided and intersect each other. In addition, the first to twelfth tangential rib pairs A and the first to twelfth tangential rib pairs B also cross the annular rib 50 ,

In addition, as in 3 shown, three projections, d. h, extending portions 51 . 52 . 53 integral with the inner surface of the front panel portion 32 provided to project inward. From these intersect the extending parts 51 . 52 with the annular rib 50 while the extending portion 53 to one side of the annular rib 50 is moved. As in 4 are shown when the Taktststabdeckungabdeckung C on the engine body 1 moored, free ends of these extending portions 51 . 52 . 53 in contact with the one side surface of the engine body 1 to the strength of attachment of the plate-shaped front side portion 32 the timing harness cover C on the engine body 1 and also to suppress diaphragm vibration of the timing belt cover C.

In addition, around the plate-shaped front side portion 32 to reinforce, on the inner surface of the front side portion 32 multiple reinforcement seats 54 in a scattered manner inward in the periphery of the insertion hole 34 and outside the annular rib 50 educated.

The reinforcing seats 54 are extrusion seats which are used when the timing strand cover C is extruded from a mold to be molded. When the timing harness cover C is released from the mold, the seats are pushed from the mold side by pins to push out the timing harness cover C, which is a product. Due to their large thickness, the seats have a high rigidity and a reinforcing effect.

The reinforcing seats 54 are in the periphery of the insertion hole 34 arranged at equal intervals in the peripheral direction.

The timing harness cover C, which is configured as described above, is integrally formed on the one side surface of the engine body as described below 1 appropriate. Specifically, the inner surface of the timing string cover C comes into contact with the one side surface of the engine body 1 brought the cylinder block 2 and the cylinder head 3 includes. The connecting bolts 15 are respectively in the projection holes of the multiple fastening portions 31 , which in the peripheral portion 30 the clock strand cover C are provided inserted and the attachment portions 31 be on the engine body 1 fixed.

When the timing transmission mechanism T by the rotation of the crankshaft 6 is operated in the operation of the engine E, a vibration due to the rotation and the operation on the oil seal 35 and the insertion hole 34 transferred to the Taktststrangabdeckung C.

Here's the insertion hole 34 itself, which is the projection hole, has high rigidity and, in contrast, the front side portion 32 around the projection hole has a low rigidity, a vibration is generated. In this regard, the periphery of the insertion hole 34 which has high rigidity, which are the projection holes through which the reinforcing rib group R is finely divided. In addition, the linear tangential ribs 40 is connected to the projection hole having high rigidity so as to be capable of membrane vibration occurring in the periphery of the insertion hole 34 is generated, thereby making it possible to effectively suppress the generation of noise due to the vibration while suppressing an increase in weight.

In addition, the multiple tangential rib pairs A, B are the linear tangential ribs 40 symmetrically with respect to the center CE of the insertion hole 34 intended. Moreover, the multiple tangential rib pairs A, B which cross each other are over the entire periphery of the insertion hole 34 at every predetermined angle, thereby being capable of the periphery of the insertion hole 34 uniformly reinforcing over the entire periphery, thereby enabling the effect of reducing membrane vibration occurring in the periphery of the insertion hole 34 is generated to further amplify, while the weight increase is suppressed.

In the foregoing, the embodiment of the present invention is described. However, the present invention is not limited to the embodiment, and various other embodiments are possible within the scope of the present invention.

For example, the case where the reinforcing rib group is formed on the inner surface of the front side portion of the timing belt cover is described in the above-described embodiment. However, the reinforcing rib group may be formed on an outer surface of the front side portion of the timing harness cover. In addition, the case where the reinforcing rib group according to the present invention is formed in the periphery of the insertion hole for inserting the crankshaft in the timing belt cover is described in the embodiment. However, the reinforcing rib group according to the present invention may be formed in a periphery of an insertion hole for inserting the valve camshaft or other rotating shaft in the timing belt cover.

LIST OF REFERENCE NUMBERS

1

motor body

6

Rotary shaft (crankshaft)

3

cylinder head

30

peripheral portion

31

Mounting portion

32

Front portion

34

insertion hole

50

annular rib

51

extending portion

52

extending portion

53

extending portion

A

tangential rib pair

B

tangential rib pair

C

Clocking strand cover

CE

Center of insertion hole 34

T

Timing transmission mechanism

An object is to reduce a diaphragm surface vibration generated in a periphery of an insertion hole for inserting a rotary shaft formed in a front side portion of a timing harness cover structure which is adapted to cover a timing transmission mechanism of an internal combustion engine and moored to a side of an engine body of the internal combustion engine be.

As a means for solving, a reinforcing rib group R is in a periphery of the insertion hole 34 which is in a front part of the area 32 a Taktstrangabdeckungsstruktur C is formed, for inserting a rotary shaft 6 provided, wherein the reinforcing rib group R multiple linear tangential ribs 40 which extends in tangential directions of the insertion hole 34 extend and intersect each other.

Claims (6)

A timing belt cover structure for an internal combustion engine, wherein the timing train cover structure is adapted to be mounted on one side of an engine body ( 1 ) of an internal combustion engine (E) and to cover a timing transmission mechanism (T) of the internal combustion engine (E), the timing train coverage structure comprising: a peripheral portion (16); 30 ), which has a plurality of fastening portions ( 31 ) to the engine body ( 1 ) to be attached; and a plate-shaped front side portion ( 32 ), which with the peripheral portion ( 30 ) and which is adapted to cover the timing transmission mechanism (T), an insertion hole ( 34 ) for inserting a rotary shaft ( 6 ) in the front side portion ( 32 ) is formed, a periphery of the insertion hole ( 34 ) is thicker than the front side portion ( 32 ), and a reinforcing rib group (R) integral with one of an inner surface and an outer surface of the front side portion (Fig. 32 ) is provided to the insertion hole ( 34 ), characterized in that the reinforcing rib group (R) has a plurality of linear tangential ribs ( 40 ), which like tangential lines in tangential directions of the insertion hole (FIG. 34 ) at intervals in a peripheral direction of the insertion hole (FIG. 34 ) are provided, and the linear tangential ribs ( 40 ) a projection portion in the periphery of the insertion hole ( 34 ) overlap and form part of the projection portion, the plurality of linear tangential ribs (FIG. 40 ) comprises a plurality of tangential rib pairs (A, B), in each of which tangential ribs symmetrical to each other with respect to a center (CE) of the insertion hole (FIG. 34 ) are provided and intersect each other. A timing belt cover structure for an internal combustion engine according to claim 1, wherein said tangential rib pairs (A, B) are distributed over an entire periphery of said insertion hole (16). 34 ) are provided at each uniformly predetermined angle. A timing belt cover structure for an internal combustion engine according to claim 1 or 2, wherein at least some of said plurality of linear tangential ribs ( 40 ) with the corresponding fastening portions ( 31 ) are connected. A timing belt cover structure for an internal combustion engine according to claim 1, 2 or 3, wherein the front side portion 32 ) with an annular rib ( 50 ) which surrounds the periphery of the insertion hole ( 34 ) surrounds and the majority of the linear tangential ribs ( 40 ) crosses. A timing belt cover structure for an internal combustion engine according to claim 4, wherein said annular rib (16) 50 ) tangential ribs which intersect each other, from the plurality of linear tangential ribs ( 40 ), at crossing points of the tangential ribs. A timing belt cover structure for an internal combustion engine according to claim 4 or 5, wherein said plurality of linear tangential ribs ( 40 ) and the annular rib ( 50 ) on the inner surface of the front side portion ( 32 ), a plurality of extending subregions ( 51 . 52 . 53 ), which have free ends to Contact with the engine body ( 1 ) is provided on the inner surface, and at least one of the extending portions ( 51 . 52 . 53 ) on the annular rib ( 50 ) is provided.

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