JP2021067176A - Valve timing control device of internal combustion engine - Google Patents

Abstract

To provide a valve timing control device of an internal combustion engine which enables improvement of efficiencies of manufacturing operation and assembly operation by reduction of the number of components.SOLUTION: The valve timing control device of an internal combustion engine includes: a cylindrical housing body 7; a vane rotor 9 which is disposed in the housing body 7 so as to enable relative rotation; a cover member having a plate body 110, which closes an opening of one end of the housing body, and female screw formation parts 112 which are integrally formed with the plate body and protrude along a rotation axis direction of the housing body and in each of which a female screw 112a is provided at an inner periphery; and bolts 5 which are inserted into bolt insertion holes 7a to 7e formed at the housing body in a penetrating manner from the rotation axis direction and which are respectively engage with the female screws.SELECTED DRAWING: Figure 3

Description

The present invention relates to a valve timing control device for an internal combustion engine.

For example, the conventional valve timing control device described in Patent Document 1 below includes a cylindrical housing body having a plurality of shoes integrally on the inner circumference, a front plate that closes one end opening of the housing body, and the above. It is provided with a rear plate that closes the other end opening of the housing body.

The rear plate has a plurality of holding holes formed through the rear plate at positions corresponding to the plurality of bolt insertion holes formed through the housing body. In each of the holding holes, bushes having female threads formed on the inner peripheral surface are press-fitted and held. The front plate and the rear plate are fastened together with a plurality of bolts inserted into the bolt insertion holes formed in the shoes to the housing body screwed into the female threads of the bushes. There is.

US Publication 2016/0032789 AI

However, in the conventional valve timing control device, a plurality of threaded bushes are provided separately from the rear plate. For this reason, the number of parts has increased, leading to a decrease in manufacturing work efficiency and an increase in assembly man-hours, as well as an increase in cost.

One object of the present invention is to provide a valve timing control device for an internal combustion engine that can improve the efficiency of manufacturing work and assembly work by reducing the number of parts.

In a preferred embodiment of the present invention, a vane rotor rotatably arranged inside a tubular housing body, a plate-shaped portion that closes one end opening of the housing body, and a plate-shaped portion that is integrally provided with the plate-shaped portion. A cover member having a boss portion that protrudes along the rotation axis direction of the housing body and has a female screw on the inner circumference.
It is characterized in that it is provided with a plurality of bolts that are inserted into a plurality of through holes formed through the housing body from the direction of the rotation axis and fastened to the female screw.

According to a preferred embodiment of the present invention, the number of parts can be reduced to improve the efficiency of manufacturing work and assembly work.

It is the schematic which shows the hydraulic circuit of 1st Embodiment of the valve timing control device which concerns on this invention. FIG. 1 is a cross-sectional view taken along the line AA of FIG. It is the B part enlarged view of FIG. It is a front view which shows the rear plate provided in this embodiment. It is a perspective view of the rear plate. It is a front view which looked at the valve timing control device of this embodiment from the rear plate side. It is a vertical sectional view of the valve timing control device in the 2nd Embodiment of this invention. It is a front view which looked at the valve timing control device of this embodiment from the rear plate side.

Hereinafter, an embodiment in which the valve timing control device of the internal combustion engine according to the present invention is applied to the intake valve side will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a schematic view showing a hydraulic circuit of the first embodiment of the valve timing control device according to the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 3 is an enlarged view of part B of FIG.

As shown in FIGS. 1 and 2, the valve timing control device includes a timing sprocket (hereinafter referred to as a sprocket) 1 which is a drive rotating body (drive element) that is rotationally driven by a crankshaft of an engine via a timing chain. , The cam shaft 2 on the intake side, which is arranged along the front-rear direction of the engine and is provided so as to be rotatable relative to the sprocket 1, is arranged between the sprocket 1 and the cam shaft 2, and both 1, 2 A phase changing mechanism 3 for converting the relative rotation phase of the above and a hydraulic circuit 4 for operating the phase changing mechanism 3 are provided.

The sprocket 1 is a part of the phase changing mechanism 3, and is a housing body 7 described later, which is formed in a cylindrical shape by a sintered metal formed by compressing and heating iron-based metal powder, and the housing body 7 of the housing body 7. It has a gear 1a that is integrally provided on the outer peripheral surface and is wound around a timing chain. The gear 1a is arranged slightly to the left of the center position (closer to the front plate, which will be described later) in FIG. 2 in the rotation axis direction of the outer peripheral surface of the housing body 7.

The camshaft 2 is rotatably supported by a cylinder head (not shown) via a cam bearing, and a plurality of oval cams that open and close the intake valve are integrally fixed to a predetermined position in the axial direction on the outer periphery. Further, as shown in FIG. 2, the camshaft 2 has a bolt insertion hole 2b formed in the direction of the internal axis of one end portion 2a, and a female screw hole 2c is formed on the tip end side of the bolt insertion hole 2b. ..

As shown in FIGS. 1 and 2, the phase changing mechanism 3 is housed in a housing 6 having an operating chamber inside and in the housing 6 so as to be relatively rotatable, and a cam bolt 8 is mounted on one end 2a of the camshaft 2. The vane rotor 9, which is an output element fixed from the direction of the rotation axis via the vane rotor 9, and the retard hydraulic chamber 15 and the advance hydraulic chamber 16 in which the operating chambers of the housing 6 are divided into a plurality (five in this embodiment) by the vane rotor 9. And have.

The housing 6 has a cylindrical housing body 7 shared with the sprocket 1, a front plate 10 formed by press molding and closing the front end opening of the housing body 7, and a cover that closes the rear end (one end) opening. It includes a rear plate 11 which is a member.

A plurality of (five in this embodiment) first to fifth shoes 12a to 12e are integrally provided on the inner peripheral surface of the housing main body 7 at substantially equal intervals in the circumferential direction. Inside each of the shoes 12a to 12e, five bolt insertion holes 7a to 7e are formed through the housing 6 in the direction of the rotation axis.

The five shoes 12a to 12e have different widths and lengths in the circumferential direction. That is, of the five shoes 12a to 12e, the width and length of the first shoe 12a and the second shoe 12b adjacent to the first shoe 12a in the circumferential direction (on the right side in the circumferential direction in FIG. 2) are compared. It is formed to be large and has high rigidity. On the other hand, the other shoes, the two third to fifth shoes 12c to 12e, are formed to be smaller in width and length than the first and second shoes 12a and 12b.

As described above, since the first vane 14a, which will be described later, comes into contact with the first and second shoes 12a and 12b from the circumferential direction, the width and length of the first and second shoes 12a and 12b are increased to increase the rigidity. On the other hand, since the first vane 14a does not abut on the three third to fifth shoes 12c to 12e, the thickness is reduced to reduce the weight.

Further, the housing main body 7 is provided with recessed grooves 114, which are recesses, at the hole edges of the bolt insertion holes 7a to 7e on the rear plate 11 side. Each of the concave grooves 114 is formed in a cylindrical shape from the hole edge of each bolt insertion hole 7a to 7e to the inner peripheral surface. Further, each concave groove 114 is formed so that its depth D1 is slightly deeper than the axial length of the female screw component 112, which will be described later, and the inner diameter is slightly larger than the outer diameter of the female thread component 112. Has been done. The inner diameters of the five recessed grooves 114 are formed to be larger than the inner diameters of the bolt insertion holes 7a to 7e, and the entire structure is set to be substantially uniform.

The cam bolt 8 is formed on the head portion 8a on the front plate 10 side, the shaft portion 8b extending from the head portion 8a to the camshaft 2 side, and the tip end side of the shaft portion 8b, and is formed into a female screw hole of the camshaft 2. It is composed of a male screw portion 8c screwed to 2c and a male screw portion 8c.

The front plate 10 is formed, for example, by press-molding an iron-based metal plate into a disk shape, and a large-diameter insertion hole 10a into which a bolt 8 is inserted is formed through the front plate 10. Further, the front plate 10 is formed with five bolt insertion holes 10b penetrating the outer peripheral portion at substantially equal intervals in the circumferential direction. The formation positions of the bolt insertion holes 10b correspond to the bolt insertion holes 7a to 7e of the shoes 12a to 12e.

FIG. 4 is a front view showing the rear plate used in the present embodiment, FIG. 5 is a perspective view of the rear plate, and FIG. 6 is a front view of the valve timing control device of the present embodiment as viewed from the rear plate side.

As shown in FIGS. 2, 4 to 6, the rear plate 11 is formed by press-molding a steel (carbon steel) material plate into a disk shape. The rear plate 11 has a plate main body 110 which is a disk-shaped plate-shaped portion, and an annular rib 111 which is an annular rib integrally provided on the outer peripheral edge of the plate main body 110.

The plate body 110 is formed through a shaft insertion hole 110a into which one end portion 2a of the camshaft 2 is inserted in the center. Further, the plate main body 110 is integrally provided with a plurality of (five in this embodiment) female screw constituent portions 112, which are boss portions, at positions on the outer peripheral side in the circumferential direction.

The inner diameter of the shaft insertion hole 110a is slightly larger than the outer diameter of one end 2a of the camshaft 2, and the inner peripheral surface is in non-contact with the outer peripheral surface of the one end 2a.

Each female screw component 112 is formed in a cylindrical shape extending inside the plate body 110 (in the direction of the front plate 10), and is formed by, for example, drawing, which is plastic working when the plate body 110 is pressed. It is also possible to form each female screw component 112 by bending it into a tubular shape by burring.

Further, the female thread 112a is formed on each inner peripheral surface of each female thread component 112 by plastic working. That is, it is not formed by ordinary cutting tapping or the like, but is formed by, for example, roll tapping, which is plastic working without chips.

Further, each female screw component 112 is formed so that its axial length L is shorter than the depth D1 of each concave groove 114 described above. The five female screw components 112 have four outer diameters D formed to be smaller than the inner diameter of each groove 114, and are relatively loosely fitted to the corresponding four recesses 114. On the other hand, one female screw component 112'is formed so that the outer diameter D'is slightly smaller than the inner diameter of the corresponding concave groove 114, and is fitted to the one concave groove 114 with a clearance. The rear plate 11 is positioned with respect to the housing body 7 by fitting the one female screw component 112'to the concave groove 114. That is, the clearance between the outer diameter D'of the female screw component 112'and the concave groove 114 is formed to be smaller than the clearance between the outer diameter of the four female thread components 112'and the concave groove 114 of the target.

It is also possible to form the outer diameters D'of the two female screw constituents 112'and 112'out of the five female screw constituents 112 slightly larger so as to be in close contact with the corresponding two concave grooves 114. Is.

Further, as shown in FIG. 3, each female screw component 112 has a curved rounded portion 112b formed on the outer periphery of the inner root portion with the plate main body 110. The rounded portion 112b is formed at the same time when each female screw component 112 is formed by drawing or burring, and is in a non-contact state with the hole edge of each concave groove 114. Each rounded portion 112b can also be formed by using a tool after press molding of the rear plate 11.

Further, the plate main body 110 is integrally provided with a lock hole component 113 forming a lock hole 25 of a lock mechanism described later on a part of the outer peripheral side. The lock hole component 113 is formed in a bottomed cylindrical convex shape from the inner surface side (vane rotor 9 side) of the plate body 110 to the outer surface side by drawing or the like during pressing of the rear plate 11, and the inside is a lock described later. It is a hole 25. Further, the lock hole component 113 is partially subjected to heat treatment by quenching at the time of molding or after the molding of the rear plate 11 is completed to increase the hardness.

As shown in FIGS. 2 to 5, the annular rib 111 is formed in a cylindrical shape bent at a substantially right angle from the outer peripheral edge of the plate body 110 toward the front plate 10. Further, the annular rib 111 is arranged so that its axial length is set to be substantially the same as the axial length of each female screw component 112 and covers the outer peripheral surface of the housing body 7 on the other end opening side. Has been done.

Further, the annular clearance width C1 formed between the inner peripheral surface of the annular rib 111 and the outer peripheral surface of the housing body 7 is between the outer peripheral surface of each female screw component 112 and the inner peripheral surface of the concave groove 114. The clearance width is set to be larger than the clearance width C2 of (see FIG. 3). Therefore, the annular rib 111 does not affect the positioning action of the rear plate 11 by one female screw component 112'when the rear plate 11 is assembled to the housing body.

Then, the housing body 7, the front plate 10 and the rear plate 11 are jointly fixed (co-tightened and fixed) together by five bolts 5.

As shown in FIGS. 2 and 3, each bolt 5 has a head portion 5a having a groove for engaging a tool on the tip surface, a shaft portion 5b extending from the rear end of the head portion 5a, and the shaft portion 5b. It is composed of a male screw 5c formed on the outer periphery of the tip portion of the above.

Each bolt 5 has the shaft diameter of each shaft portion 5b set to be substantially the same, and the length of each shaft portion 5b is up to the front plate 10, the housing body 7, and the female screw component 112 of the rear plate 11. It is set to the length.

Each bolt 5 is inserted into each bolt insertion hole 10b with the front plate 10 and each bolt insertion hole 7a to 7e of each shoe 12a to 12e. Further, each male screw 5c is screwed and fastened to each female screw 1c of each female screw component 112 of the rear plate 11. As a result, each bolt 5 is adapted to fasten and fix the above-mentioned front plate 10, the housing body 7, and the rear plate 11 together from the direction of the rotation axis.

The vane rotor 9 is formed integrally by, for example, compressing and sintering metal powder, and is directly fixed to one end 2a of the camshaft 2 by a cam bolt 8 and a rotor 13 in a circumferential direction on the outer peripheral surface of the rotor 13. It is composed of a plurality of first to fifth vanes 14a to 14e (five in this embodiment) radially provided at approximately 70 ° equidistant positions.

As shown in FIGS. 1 and 2, the rotor 13 is formed in a substantially cylindrical shape long in the rotation axis direction, and an insertion hole 13a into which the shaft portion 8b of the cam bolt 8 is inserted is formed through the rotor 13 along the axial direction. Has been done. Further, the rotor 13 is formed with a columnar fitting groove 13b into which one end portion 2a of the camshaft 2 is fitted inside the rear end portion on the camshaft 2 side.

As shown in FIG. 1, the first to fifth vanes 14a to 14e are integrally provided on the outer periphery of the rotor 13, and each of the first to fifth vanes 14a to 14e is arranged between the shoes 12a to 12e. Each of the five retard hydraulic chambers 15 and the advance hydraulic chamber 16 is partitioned by vanes 14a to 14e and shoes 12a to 12e.

Further, in each of the vanes 14a to 14e, one first vane 14a is formed widely in the circumferential direction, but the other four second to fifth vanes 14b to 14e are formed in a thin wall and substantially the same circumferential width. Has been done.

Further, in the seal groove formed on the outer surface of each of the tip portions of the vanes 14a to 14e, a seal member 17a that seals while sliding on the inner peripheral surface of the housing body 7 is fitted and fixed. On the other hand, a sealing member 17b that seals while sliding on the outer peripheral surface of the rotor 13 is fitted and fixed in the sealing groove formed on the inner peripheral surface of the tip of each of the shoes 12a to 12e.

When the vane rotor 9 rotates relative to the housing 6 in the counterclockwise direction of FIG. 1, one side surface 14f of the first vane 14a abuts on the opposite side surface of the first shoe 12a, and the rotation position on the maximum retard side is set. It is becoming regulated. Further, when the vane rotor 9 rotates relative to the housing 6 in the clockwise direction of FIG. 1, the other side surface 14g of the first vane 14a comes into contact with the facing side surface of the other second shoe 12b facing the housing 6, and the maximum advance angle side. The rotation position is regulated.

The first vane 14a and the two first shoes 12a and 12b function as mechanical stoppers for regulating the most retarded angle position and the most advanced angle position of the vane rotor 9.

At this time, the other four second to fifth vanes 14b to 14e are separated from each other without abutting on the facing side surfaces of the shoes 12a to 12e whose side surfaces face each other from the circumferential direction. Therefore, the contact accuracy between the first vane 14a and the two first shoes 12a and 12b is improved, and the speed of supplying the oil pressure to the hydraulic chambers 15 and 16 by the hydraulic circuit 4 is increased, so that the vane rotor 9 is forward and reverse. Rotational responsiveness is increased.

As shown in FIG. 1, the retard hydraulic chambers 15 and the advance hydraulic chambers 16 are connected to the hydraulic circuit 4 via the first and second communication holes 15a and 16a formed substantially radially inside the rotor 13. It communicates with each.

The hydraulic circuit 4 selectively supplies or discharges the hydraulic pressure to the retard and advance hydraulic chambers 15 and 16 and hydraulically supplies the retard hydraulic chambers 15 through the first communication hole 15a. The retarded oil passage 18 for supplying and discharging the oil, the advancing oil passage 19 for supplying and discharging the oil pressure to each of the advancing hydraulic chambers 16 through the second communication hole 16a, and the hydraulic oil in the oil passages 18 and 19. It is provided with an oil pump 20 which is a fluid pressure supply source for selectively supplying the flood control, and an electromagnetic switching valve 21 for switching the flow paths of the retard angle oil passage 18 and the advance angle oil passage 19 according to the operating state of the engine. ..

The oil pump 20 is a general one such as a trochoid pump that is rotationally driven by a crankshaft of an engine.

One end of each of the retard oil passage 18 and the advance oil passage 19 is connected to the passage hole of the electromagnetic switching valve 21. On the other hand, the other ends of the passages 18 and 19 are connected to the retard oil passage 18a and the advance oil passage 19a formed in the internal axial direction of the camshaft 2, respectively. The retarded oil passage portion 18a communicates with each retarded hydraulic chamber 15 via an unexpected radial hole formed in one end 2a of the camshaft and a first communication hole 15a. On the other hand, the advance angle oil passage portion 19a communicates with each advance angle hydraulic chamber 16 via an unexpected radial hole formed in one end portion 2a of the camshaft and a second communication hole 16a.

The electromagnetic switching valve 21 is a proportional valve with 4 ports and 3 positions, and is a spool valve body (not shown) provided in the valve body 21a so as to be slidable in the axial direction by a pulse current output from the control unit 24. To move back and forth. As a result, the discharge passage 20a of the oil pump 20 and one of the oil passages 18 and 19 are communicated with each other, and at the same time, the other oil passages 18 and 19 and the drain passage 22 are communicated with each other.

The suction passage 20b and the drain passage 22 of the oil pump 20 communicate with each other in the oil pan 23. Further, a filtration filter (not shown) is provided on the downstream side of the discharge passage 20a of the oil pump 20, and the main oil gallery M / G supplies lubricating oil to the sliding parts of the internal combustion engine on the downstream side. It communicates with. Further, the oil pump 20 is provided with a relief valve (not shown) for discharging excess hydraulic oil discharged from the discharge passage 20a to the oil pan 23 to control the discharge flow rate to an appropriate level.

In the control unit 24, an internal computer detects the current rotation phase of a crank angle sensor (engine rotation speed detection), an air flow meter, an engine water temperature sensor, an engine temperature sensor, a throttle valve opening sensor, and a camshaft 2, which are not shown in the figure. Information signals from various sensors such as the cam angle sensor are input to detect the current engine operating state. Further, the control unit 24 outputs a control pulse current to the coil of the electromagnetic switching valve 21 to control the moving position of each spool valve body to switch and control each passage.

Further, a lock mechanism for locking the vane rotor 9 to the rotation position (position in FIG. 2) on the most retarded angle side with respect to the housing 6 is provided.

As shown in FIGS. 1 and 2, the lock mechanism is provided in the lock hole 25 formed inside the lock hole component 113 provided in the rear plate 11 and in the internal axial direction of the first vane 14a. The accommodating hole 26, the lock pin 27 which is slidably provided in the accommodating hole 26 and is a lock member whose tip portion is inserted into or out of the lock hole 25, and the lock pin 27 is inserted into the lock hole 25. It is mainly composed of a pair of release passages 29a and 29b to be released.

The inner diameter of the lock hole 25 is formed to be slightly larger than the outer diameter of the tip portion 27b of the lock pin 27, and these clearances are set with high accuracy.

The accommodating hole 26 is formed through the inside of the first vane 14a along the rotor 13 axial direction, and the inner diameter is substantially uniform in the axial direction.

The lock pin 27 is composed of a pin body 27a slidably arranged in the accommodating hole 26 and a small-diameter tip 27b integrally provided on the tip side of the pin body 27a via an annular step portion. ing.

The outer peripheral surface of the pin body 27a is formed into a simple straight cylindrical surface so as to slide liquid-tightly in the accommodating hole 26. The tip portion 27b is formed in a columnar shape, and the outer diameter is set to be slightly smaller than the inner diameter of the lock hole 25.

Further, the lock pin 27 has a tip 27b in the lock hole 25 due to the spring force of a spring 28 mounted between the bottom surface of the concave groove formed in the internal axial direction from the rear end side and the inner surface of the front plate 10. It is urged in the direction of entry.

The step portion functions as a pressure receiving surface that receives the hydraulic pressure introduced from one of the release passages 29a. That is, the hydraulic pressure acting on the pressure receiving surface causes the lock pin 27 to retract from the lock hole 25 against the spring force of the spring 28 to release the lock.

As shown in FIG. 1, the release passages 29a and 29b are formed on both sides of the first vane 14a, and the lock hole 25 and the step portion (pressure receiving surface) from the retard angle hydraulic chamber 15 and the advance angle hydraulic chamber 16 are formed. It is designed to supply flood control to the vehicle. Therefore, the lock pin 27 receives the hydraulic pressure supplied to the retard hydraulic chamber 15 or the advance hydraulic chamber 16 from the corresponding release passages 29a and 29b. As a result, the lock pin 27 comes out of the lock hole 25 and is unlocked.

The vane rotor 9 has an air vent groove 9a that communicates with the outside through the rear end of the accommodating hole 26 and the insertion hole 10a of the front plate 10 on the front end surface on the front plate 10 side. The air vent groove 9a is for ensuring the smooth slidability of the lock pin 27 in the accommodating hole 26.
[Operation of the present embodiment]
Hereinafter, the operation of the valve timing control device in the present embodiment will be briefly described.

When the ignition switch is turned off, the operation of the oil pump 20 is stopped, so that the supply of oil to the retard hydraulic chambers 15 and the advance hydraulic chambers 16 is stopped. Then, the vane rotor 9 rotates relative to the housing 6 on the retard side due to a particularly negative alternating torque acting on the camshaft 2 until the engine is completely stopped. Therefore, in the vane rotor 9, the first vane 14a abuts on one side surface of the first shoe 12a and is restricted to the relative rotation position on the maximum retard side.

At this point, the lock pin 27 enters the lock hole 25 by the spring force of the spring 28 and locks the vane rotor 9 with respect to the housing 6 to regulate free relative rotation.

After that, when the ignition switch is turned on to restart the engine, the opening / closing timing of the intake valve during cranking is on the retard side at this point, so the start can be stabilized and the startability can be improved. ..

After that, when the engine shifts to the idling operation, the electromagnetic switching valve 21 communicates the discharge passage 20a and the retard oil passage 18 by the control current output from the control unit 24, and also connects the advance oil passage 19 and the drain passage 22. Communicate. Therefore, the oil pressure discharged from the oil pump 20 to the discharge passage 20a flows into each retard angle hydraulic chamber 15 through the retard angle oil passage 18 and the like. Further, this hydraulic pressure flows into the lock hole 25 through the release passage 29a and acts on the tip portion 27b of the lock pin 27. Therefore, the lock pin 27 retracts against the spring force of the spring 28, the tip portion 27b comes out of the lock hole 25, and the lock is released. As a result, the vane rotor 9 is ensured to rotate freely.

Further, the hydraulic oil of each advance hydraulic chamber 16 is discharged from the drain passage 22 to the oil pan 23 through the advance oil passage 19.

Therefore, the pressure inside each retard hydraulic chamber 15 becomes high, while the pressure inside each advance hydraulic chamber 16 becomes low. Therefore, the vane rotor 9 rotates relative to the retarded angle side, one side surface of the first vane 14a abuts on the opposite side surface of the first shoe 12a, and the vane rotor 9 is regulated and held at the rotational position on the most retarded angle side.

As a result, the amount of valve overlap between the intake valve and the exhaust valve is reduced, the blowback of the combustion gas is suppressed, a good combustion state can be obtained, fuel efficiency is improved, and engine rotation is stabilized.

When the engine operating state changes and, for example, the medium load region is reached, the electromagnetic switching valve 21 communicates with each retard angle oil passage 18 and the drain passage by the control signal from the control unit 24, and advances each step. The square oil passage 19 communicates with the discharge passage 20a. Therefore, each advance hydraulic chamber 16 has a high pressure, and each retard hydraulic chamber 15 has a low pressure. Therefore, the hydraulic oil in each advance angle hydraulic chamber 16 acts on the pressure receiving surface through the other release passage 29b, and the state in which the lock pin 27 is retracted from the lock hole 25 is maintained. As a result, the vane rotor 9 rotates relative to the advance angle side, the other side surface of the first vane 14a abuts on the opposite side surface of the second shoe 12b, and the vane rotor 9 is regulated and held at the rotation position on the most advance angle side.

As a result, the amount of valve overlap between the intake valve and the exhaust valve becomes large, the combustion temperature is lowered, and NOx in the exhaust gas is reduced. In addition, the unburned gas can be reburned to reduce HC.

Further, in the present embodiment, since each female screw component 112 is provided integrally with the rear plate 11, the number of parts can be reduced. That is, when the threaded bush is provided separately from the plate-shaped portion (rear plate) as in the above-mentioned conventional technique, the number of parts is inevitably increased, which leads to a decrease in manufacturing work and assembly work efficiency. I am.

However, since each female screw component 112 is provided integrally with the plate body 110 of the rear plate 11 as in the present embodiment, the number of parts can be reduced. As a result, the manufacturing work efficiency is improved, and since it is not necessary to assemble each female screw component 112 to the plate body 110 in the first place, the work efficiency can be improved. Moreover, since many parts management is not required, this management cost can be reduced.

Moreover, since each female screw component 112 is formed by drawing, which is also plastic working, at the time of press molding of the rear plate 11, the molding work efficiency can be improved. Further, since the same press molding is performed, there is no joint between each female screw component 112 and the plate body 110, so that the appearance quality is improved.

Further, since each female screw component 112 is formed by drawing, the metal flow, which is a fibrous metal structure inside the metal, is formed from the plate body 110 by plastic deformation during press molding of the rear plate 11. The direction changes smoothly over 112. Therefore, breakage of each female screw component 112 and the plate body 110 is suppressed.

Further, since each female screw 112a of each female screw component 112 is formed by the roll tap method which is plastic working, the metal flow is not cut. That is, when each female thread 112a is formed by a cutting process such as threading with a die, the strength of each female thread component 112 may decrease because the metal flow is cut. However, in the case of the present embodiment, since there is no cutting of the metal flow, it is possible to suppress a decrease in the strength of each female screw component 112.

Further, in the cutting process, the wall thickness of each female screw component 112 is reduced by the amount of chips, so the wall thickness of both the female thread component 112 and the plate body 110 must be increased in consideration of the amount. However, since chips are not generated in the case of plastic working, the wall thickness of each female screw component 112 and the plate body 110 can be reduced. As a result, the thickness of the rear plate 11 can be reduced.

Further, a rounded portion 112b is provided at the base of each female screw component 112. Therefore, when each bolt 5 is tightened, each rounded portion 112b is in a non-contact state with the hole edge of each concave groove 114. Therefore, the tightening torque of each bolt 5 can be distributed to the plate body 110 without being directly applied to the rounded portion 112b. As a result, sufficient tightening strength of each bolt 5 can be ensured.

Further, in the present embodiment, at least one female screw component 112'is inserted tightly into the concave groove 114. Therefore, the female screw component 112'can be used for positioning when the rear plate 11 is assembled to the housing body 7. As a result, a dowel pin or the like is not required separately, so that the number of parts can be reduced in this respect as well, and the efficiency of manufacturing work and assembly work can be improved.

Since the ring rib 111 is integrally provided on the outer periphery of the plate main body 110, the strength of the rear plate 11 is increased as a whole. Therefore, it is possible to receive a high tightening torque of each bolt 5 for each female screw 112a. Therefore, the side clearance between the plate body 110 and the vane rotor 9 can be uniformly maintained, so that the sealing performance can be improved. Further, by ensuring the high strength of the entire rear plate 11, the thickness of the rear plate 11 can be reduced as a result, and thus the weight reduction can be promoted.

Further, since the annular rib 111 projects toward the front plate 10 so as to cover the outer peripheral surface of the housing body 7 on the opening side at one end in the rotation axis direction, it is possible to suppress the lengthening of the entire device in the axial direction. ..

Further, since the lock hole component 113 is integrally provided with the plate main body 110, the efficiency of manufacturing work and assembly work can be improved as compared with the case where the lock hole component 113 is provided separately. Moreover, since the lock hole constituent portion 113 is hardened to have a high hardness, it is possible to sufficiently suppress the occurrence of wear even if the tip portion 27b of the lock pin 27 is repeatedly inserted.
[Second Embodiment]
7 and 8 show a second embodiment of the present invention. In this embodiment, each female screw component 112 is extended from the outer surface of the plate body 110 in the direction opposite to the front plate 10.

That is, the housing main body 7 eliminates each concave groove 114 having on the hole edge on the one-side opening side in the axial direction, and merely has each bolt insertion hole 13d.

The rear plate 11 (plate body 110) is provided with each female screw component 112 projecting outward in the axial direction from the outer surface of the plate body 110 at a position corresponding to each bolt insertion hole 13d. As in the first embodiment, each female screw component 112 is formed into a cylindrical shape by drawing during press molding of the rear plate 11. Further, each female screw 112a is formed by a roll tap method. The length of each female screw component 112 in the axial direction is substantially the same as that of the first embodiment, and the length is set so that the tightening torque of the male screw 5c of the bolt 5 fastened to the female screw 112a is sufficiently secured. Has been done.

Therefore, according to this embodiment, since each female screw component 112 is provided integrally with the rear plate 11, the number of parts can be reduced and the effect is the same as that of the first embodiment.

Further, since each female screw component 112 is projected outward from the outer surface of the plate main body 110, the axial length of the device is increased by that amount, but it is necessary to form a concave groove 114 in the housing main body 7. It disappears. Therefore, the manufacturing work becomes easy.

Since the other structure and processing method of the rear plate 11 are the same as those in the first embodiment, the same effect can be obtained.

The present invention is not limited to the configuration of each of the above-described embodiments, and for example, the drive rotating body may be a pulley instead of the sprocket 1.

Further, the lock hole of the lock mechanism is not provided so that the lock hole component 113 protrudes from the plate main body 110 as in each embodiment, but a separately hard metal annular lock hole is provided inside the plate main body 110. It is also possible to provide constituent members. In this case, for example, the length of the lock pin 27 in the axial direction is shortened.

It is also possible to form the rear plate 11 by forging, and in this case, each female screw component 112 is also formed by forging.

Further, the present invention can be widely applied to an electric valve timing control device using an electric motor or the like, in addition to a hydraulic valve timing control device using a vane rotor or the like.

As the valve timing control device for the internal combustion engine based on the embodiment described above, for example, the one described below can be considered.

A preferred embodiment of the present invention is a valve timing control device for an internal combustion engine, which comprises a tubular housing body and a tubular housing body.
A vane rotor arranged so as to be relatively rotatable inside the housing body,
It has a plate-shaped portion that closes one end opening of the housing body, and a boss portion that is integrally provided in the plate-shaped portion and projects along the rotation axis direction of the housing body and has an internal thread provided on the inner circumference. Cover member and
It is provided with a plurality of bolts that are inserted into a plurality of through holes formed through the housing body from the direction of rotation axis and fastened to the female screw.

More preferably, the boss portion is formed by plastic working a part of the plate-shaped portion.

More preferably, the female screw is formed by plastic working on the inner peripheral surface of the boss portion.

More preferably, the boss portion has a curved rounded portion formed on the outer periphery of the root portion on the plate-shaped portion side.

More preferably, the boss portion is formed by drawing as well as pressing the cover member.

More preferably, the boss portion is formed by the same forging molding at the time of forging molding of the cover member.

More preferably, the housing body has recesses on the edge of each of the through holes on the cover member side, and each boss portion of the cover member is inserted into each of the recesses.

More preferably, of the recesses and the bosses, at least the corresponding set of clearances between the recesses and the bosses is smaller than the clearance between the other recesses and the bosses.

More preferably, the recess is a part of the through hole, and the inner diameter is set to be larger than the inner diameter of the through hole.

More preferably, the plate-shaped portion has an annular rib on the outer circumference.

More preferably, the annular rib covers the outer periphery of the housing body on the opening side at one end in the rotation axis direction.

More preferably, the housing body has a recess in which the boss portion is inserted into the hole edge of the through hole on the cover member side, and the inner peripheral surface of the annular rib and the outer peripheral surface of the housing body. The clearance between them is set to be larger than the clearance between the inner peripheral surface of the recess and the outer peripheral surface of the boss portion.

More preferably, it has a lock member slidably accommodated inside the accommodating hole formed in the vane rotor, and a lock recess formed in the cover member into which the lock member can be inserted and removed. ing.

More preferably, the lock recess is formed in a convex shape from the plate-shaped portion to the side opposite to the vane rotor along the rotation axis direction of the housing body.

More preferably, the boss portion projects from the plate-shaped portion in the direction opposite to the housing body in the rotation axis direction of the housing body.

Another preferred embodiment is a valve timing control device for an internal combustion engine.
A drive element to which the rotational force from the crankshaft is transmitted, an output element that is rotatably arranged relative to the drive element and fixed to the camshaft,
A cover member having a plate-shaped portion fixed to the driving element, and a boss portion that is bent in a tubular shape in the direction of the rotation axis of the driving element and protrudes from the plate-shaped portion and has a female screw inside.
It is provided with a bolt that is inserted into a through hole formed through the drive element and fastened to the female screw of the boss portion.

1 ... Sprocket (driving rotating body, driving element), 2 ... Camshaft, 3 ... Phase change mechanism, 4 ... Hydraulic circuit, 5 ... Bolt, 5c ... Male screw, 6 ... Housing, 7 ... Housing body, 7a to 7e ... Bolt Insertion hole, 8 ... cam bolt, 9 ... vane rotor (driven rotating body, output element), 10 ... front plate, 11 ... rear plate (cover member), 15 ... retard hydraulic chamber, 16 ... advance hydraulic chamber, 13 ... rotor , 14a-14e ... 1st to 5th vanes, 18 ... retard oil passage, 19 ... advance oil passage, 20 ... oil pump, 21 ... electromagnetic switching valve, 22 ... drain passage, 25 ... lock hole (lock recess) , 27 ... Lock pin (lock member), 110 ... Plate body, 111 ... Ring rib, 112 ... Female screw component (boss part), 112a ... Female thread, 112b ... Earl part, 113 ... Lock hole component, 114 ... Concave Groove (recess).

Claims (16)

It is a valve timing control device for internal combustion engines.
Cylindrical housing body and
A vane rotor arranged so as to be relatively rotatable inside the housing body,
It has a plate-shaped portion that closes one end opening of the housing body, and a boss portion that is integrally provided in the plate-shaped portion and projects along the rotation axis direction of the housing body and has an internal thread provided on the inner circumference. Cover member and
A plurality of bolts that are inserted into a plurality of through holes formed through the housing body from the direction of rotation axis and fastened to the female screw, and a plurality of bolts.
A valve timing control device for an internal combustion engine, which is characterized by being equipped with. The valve timing control device for an internal combustion engine according to claim 1.
The valve timing control device for an internal combustion engine, wherein the boss portion is formed by plastic working a part of the plate-shaped portion. The valve timing control device for an internal combustion engine according to claim 2.
The female screw is a valve timing control device for an internal combustion engine, characterized in that the inner peripheral surface of the boss portion is formed by plastic working. The valve timing control device for an internal combustion engine according to claim 2.
The boss portion is a valve timing control device for an internal combustion engine, characterized in that a curved rounded portion is formed on the outer periphery of a root portion on the plate-shaped portion side. The valve timing control device for an internal combustion engine according to claim 2.
The valve timing control device for an internal combustion engine, wherein the boss portion is formed by drawing processing together with pressing processing of a cover member. The valve timing control device for an internal combustion engine according to claim 2.
The valve timing control device for an internal combustion engine, wherein the boss portion is formed by the same forging molding at the time of forging molding of the cover member. The valve timing control device for an internal combustion engine according to claim 1.
The valve timing of an internal combustion engine is characterized in that the housing body has recesses on the edge of each of the through holes on the cover member side, and each boss portion of the cover member is inserted into each recess. Control device. The valve timing control device for an internal combustion engine according to claim 7.
An internal combustion engine characterized in that the clearance between at least a corresponding set of the recesses and the boss portion among the recesses and the boss portions is smaller than the clearance between the other recesses and the boss portions. Valve timing controller. The valve timing control device for an internal combustion engine according to claim 7.
A valve timing control device for an internal combustion engine, wherein the recess is a part of the through hole and the inner diameter is set to be larger than the inner diameter of the through hole. The valve timing control device for an internal combustion engine according to claim 1.
The valve timing control device for an internal combustion engine, wherein the plate-shaped portion has an annular rib on the outer periphery thereof. The valve timing control device for an internal combustion engine according to claim 10.
The valve timing control device for an internal combustion engine, wherein the annular rib covers the outer periphery of the housing body on the opening side at one end in the rotation axis direction. The valve timing control device for an internal combustion engine according to claim 11.
The housing body has a recess in which the boss portion is inserted into the hole edge of the through hole on the cover member side.
An internal combustion engine characterized in that the clearance between the inner peripheral surface of the annular rib and the outer peripheral surface of the housing body is larger than the clearance between the inner peripheral surface of the recess and the outer peripheral surface of the boss portion. Valve timing control device. The valve timing control device for an internal combustion engine according to claim 1.
A lock member slidably accommodated inside the accommodating hole formed in the vane rotor, and
A lock recess formed in the cover member through which the lock member can be inserted and removed.
A valve timing control device for an internal combustion engine. The valve timing control device for an internal combustion engine according to claim 13.
A valve timing control device for an internal combustion engine, wherein the lock recess is formed in a convex shape from the plate-shaped portion to the side opposite to the vane rotor along the rotation axis direction of the housing body. The valve timing control device for an internal combustion engine according to claim 1.
A valve timing control device for an internal combustion engine, wherein the boss portion projects from the plate-shaped portion in a direction opposite to the housing body in the rotation axis direction of the housing body. It is a valve timing control device for internal combustion engines.
The drive element that transmits the rotational force from the crankshaft and
An output element that is rotatably arranged relative to the drive element and fixed to the camshaft,
A cover member having a plate-shaped portion fixed to the driving element, and a boss portion that is bent and protrudes from the plate-shaped portion in a tubular shape in the direction of the rotation axis of the driving element and has a female screw inside.
A bolt that is inserted into a through hole formed through the drive element and fastened to the female screw of the boss portion.
A valve timing control device for an internal combustion engine, which is characterized by being equipped with.

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