JP2011027083A - Cam shaft device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cam shaft device capable of leading oil to an oil passage at a cam shaft side while suppressing the reduction of the oil pressure of the oil fed from a hydraulic feeding source. <P>SOLUTION: The oil is fed to an assembling part 31 assembled to the cam shaft 20 through a cam journal 10 for rotatably supporting the cam shaft 20. A rolling bearing 40 for the cam shaft 20 is arranged on the cam journal 10. On an outer ring body 42 of the rolling bearing 40, an oil hole 45 communicating with the hydraulic feeding source is formed. Between an outer peripheral surface of an inner ring body 50 of the rolling bearing 40 and an inner peripheral surface of the outer ring body 42, communication passages 65 for making the oil hole 45 communicate with the oil passage 25 at the cam shaft 20 side are dividedly formed of annular seal members 60, 61 arranged with a predetermined space in an axial direction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a camshaft device that supplies oil to an assembly part (for example, a variable valve timing mechanism) that is assembled to a camshaft through a cam journal that rotatably supports the camshaft.

This type of camshaft device is disclosed in Patent Document 1, for example.
In this case, a cam shaft is rotatably supported by a slide bearing on a cam journal (first journal) formed between a cylinder head and a cap member.
Further, in order to supply oil for controlling the variable valve timing mechanism at the end of the camshaft through the cam journal, a communication hole that connects the oil hole of the cap member and the oil passage of the camshaft is formed in the slide bearing. .
Further, the sliding bearing has a larger torque loss due to the frictional resistance than the rolling bearing. For this reason, it is known that a camshaft is rotatably supported on a cam journal using a rolling bearing (see, for example, Patent Document 2).

JP 2007-327362 A JP 2006-250268 A

By the way, when the cam journal (No. 1 journal) configured between the cylinder head and the cap member is rotatably supported by a rolling bearing having a low frictional resistance instead of a sliding bearing, it passes through the inside of the rolling bearing. It becomes the structure which supplies oil.
In this case, when the oil supplied from the hydraulic supply source flows into the oil passage on the camshaft side through the inside of the rolling bearing, it is assumed that the hydraulic pressure is reduced inside the rolling bearing and adversely affects the variable valve timing mechanism. .
Moreover, it is assumed that the oil which flowed into the inside of a rolling bearing becomes rolling resistance of the rolling element of a rolling bearing.

  In view of the above problems, an object of the present invention is to provide a camshaft device capable of guiding oil to an oil passage on the camshaft side while suppressing a decrease in oil pressure of oil supplied from a hydraulic supply source.

In order to solve the above problems, a camshaft device according to a first aspect of the present invention is a camshaft device that supplies oil to an assembly part that is assembled to the camshaft through a cam journal that rotatably supports the camshaft. There,
The cam journal is provided with a rolling bearing for the camshaft,
An oil hole leading to a hydraulic pressure supply source is formed in the outer ring body of the rolling bearing,
Between the outer peripheral surface of the inner ring body of the rolling bearing and the inner peripheral surface of the outer ring body, there is an annular communication path that connects the oil hole to the oil path on the camshaft side with a predetermined interval in the axial direction. It is characterized by being partitioned by a seal member.

According to the above configuration, the oil supplied from the hydraulic pressure supply source flows into the communication path in the rolling bearing through the oil hole of the outer ring body, and then flows into the oil path on the camshaft side.
The communication path in the rolling bearing is defined by an annular seal member that is spaced apart in the axial direction between the outer peripheral surface of the inner ring body of the rolling bearing and the inner peripheral surface of the outer ring body.
For this reason, the oil that has flowed into the communication passage in the rolling bearing flows into the oil passage on the camshaft side in a state of being sealed by both seal members. In other words, the oil that has flowed into the communication path in the rolling bearing can be prevented from leaking to the raceway surface side of the rolling bearing by the both seal members.
As a result, it is possible to satisfactorily guide the oil that has flowed into the communication passage in the rolling bearing to the oil passage on the camshaft side while suppressing a decrease in oil pressure, and to supply the oil to the camshaft assembly parts without a shortage. .

A camshaft device according to claim 2 is the camshaft device according to claim 1,
Assembly parts are variable valve timing mechanism,
The cam journal is the first journal arranged in the vicinity of the variable valve timing mechanism,
Rolling bearings have double row rolling elements,
The communication path is defined by two annular seal members spaced apart in the axial direction between the double row rolling elements.

According to the above configuration, since the cam journal is the first journal arranged in the vicinity of the variable valve timing mechanism, the oil passage on the camshaft side can be shortened.
The communication passage in the rolling bearing is defined by an annular seal member that is spaced apart in the axial direction between the double row rolling elements.
For this reason, both the sealing members can prevent the oil that has flowed into the communication path in the rolling bearing from leaking to the double row rolling element side.
As a result, the oil flowing into the communication passage in the rolling bearing can be guided well to the oil passage on the camshaft side while suppressing the decrease in oil pressure, and the oil is supplied to the variable valve timing mechanism at the end of the camshaft without a shortage. In addition, it is possible to prevent a problem that the rolling resistance of the double row rolling elements is increased by the oil leaking to the double row rolling elements.

A camshaft device according to claim 3 is the camshaft device according to claim 2,
On the inner peripheral surface located between the outer ring raceway surfaces of the double row of the outer ring body, both annular grooves that are spaced apart in the axial direction are formed, respectively.
Both annular seal members are characterized in that their respective outer diameter portions are fitted into the annular grooves.

  According to the above configuration, the outer diameter portions of the two annular seal members are fitted and disposed in the two annular grooves on the inner peripheral surface of the outer ring body, so that the two annular seal members in the axial direction are arranged. Unexpected misalignment can be prevented. For this reason, a communicating path can be maintained in a division state by both annular seal members.

It is a longitudinal cross-sectional view which shows the camshaft apparatus which concerns on Example 1 of this invention. It is the longitudinal cross-sectional view which expands and similarly shows the 1st journal of a camshaft apparatus. FIG. 3 is an end view of the camshaft along the line III-III in FIG. 1. It is a longitudinal cross-sectional view which shows the camshaft apparatus which concerns on Example 2 of this invention. It is the longitudinal cross-sectional view which expands and similarly shows the 1st journal of a camshaft apparatus. FIG. 5 is an end view of the camshaft along the line VI-VI in FIG. 4. It is a longitudinal cross-sectional view which expands and shows the 1st journal of the camshaft apparatus which concerns on Example 3 of this invention. It is a longitudinal cross-sectional view which expands and shows the 1st journal of the camshaft apparatus which concerns on Example 4 of this invention. It is a longitudinal cross-sectional view which expands and shows the 1st journal of the camshaft apparatus which concerns on Example 5 of this invention.

  The best mode for carrying out the present invention will be described in accordance with an embodiment.

A first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the camshaft device according to the first embodiment of the present invention is rotatable to a cam journal (the first journal 10 and other journals) configured between the cylinder head 1 and the cap member 5. A camshaft 20 to be supported, a plurality of cams 21 arranged at predetermined intervals on the axis of the camshaft 20, a rolling bearing (ball bearing in FIG. 1) 40 corresponding to the first journal 10, and others And a rolling bearing (not shown) corresponding to the journal.
In the cylinder head 1, arc concave portions 2 are formed in portions corresponding to the first journal 10 and other journals, and a cap member 5 having an arc concave portion 6 corresponding to the arc concave portions 2 is attached to the cylinder head 1 with bolts. Tightened by etc.
The cap member 5 corresponding to the first journal 10 is formed with an oil hole 7 communicating with a hydraulic supply source (hydraulic pump).

The rolling bearing 40 corresponding to the first journal 10 includes an outer ring body 42, an inner ring body 50, double row balls 55 and 57 as rolling elements, and cages 56 and 58.
The inner ring body 50 is formed in a cylindrical shape that is press-fitted and fixed to the outer peripheral surface of the camshaft 20, and both inner ring raceway surfaces 51, 52 facing the double-row balls 55, 57 are axially arranged on the outer peripheral surface. Are formed at a predetermined distance.
Further, both outer ring raceway surfaces 43 and 44 corresponding to both inner ring raceway surfaces 51 and 52 are formed on the inner circumference surface of the outer ring body 42 that is assembled to the outer circumference surface of the inner ring body 50 with an annular space therebetween.
Further, between the inner ring raceway surfaces 51 and 52 and the outer ring raceway surfaces 43 and 44, double rows of balls 55 and 57 are assembled so as to be able to roll while being held by the cages 56 and 58. .

As shown in FIG. 2, an oil hole 45 is formed in a radial direction in a portion located at an intermediate portion between both outer ring raceway surfaces 43 and 44 of the outer ring body 42. The oil hole 45 has an outer end that opens to the outer peripheral surface of the outer ring body 42 and communicates with the oil hole 7 of the cap member 5, and an inner end that opens to the inner peripheral surface of the outer ring body 42.
Between the outer peripheral surface of the inner ring body 50 and the inner peripheral surface of the outer ring body 42, an oil hole 45 of the outer ring body 42 is provided in an oil passage 25 on the camshaft 20 side in a portion located between the double rows of balls 55 and 57. A communication path 65 that communicates with each other is defined by annular seal members 60 and 61 that are spaced apart from each other in the axial direction.

In the first embodiment, on the inner peripheral surface located between both outer ring raceway surfaces 43, 44 of the outer ring body 42, both annular grooves 46, 47 that are spaced apart from each other in the axial direction are formed. , 47 are fitted with outer diameter portions of annular seal members 60, 61 that can be elastically expanded and contracted.
That is, the seal members 60 and 61 are formed of a metal ring, a resin ring, a rubber ring, or the like, and the outer diameter of these seal members 60 and 61 is smaller than the diameter of the bottom surface of the annular grooves 46 and 47. The inner diameter dimensions of the seal members 60 and 61 are set to be equal to the outer diameter dimension of the inner ring body 50.
In the state in which the outer diameter portions of the seal members 60 and 61 are fitted and assembled in both the annular grooves 46 and 47, the inner peripheral surface of the seal members 60 and 61 is in contact with the outer peripheral surface of the inner ring body 50, or is minute. It is designed to be close to each other with a gap.

  In the first embodiment, as shown in FIGS. 2 and 3, the oil passage 25 on the camshaft 20 side is provided with a groove 28 recessed in the axial direction of the outer peripheral surface of the camshaft 20 and the inner periphery of the inner ring body 50. A horizontal hole 27 formed in cooperation with the surface, a vertical hole 26 penetrating in the radial direction of the inner ring body 50, an outer end opening in the communication path 65, and an inner end opening in the horizontal hole 27. It is configured with.

  As shown in FIGS. 1 and 2, a knock pin 22 is driven into one end surface of the camshaft 20, and the timing gear 33 and the variable valve timing are positioned at the one end portion of the camshaft 20 by the knock pin 22. A mechanism (corresponding to the assembly part of the present invention) 31 is assembled. The variable valve timing mechanism 31 is connected to the end of the lateral hole 27 of the oil passage 25 on the camshaft 20 side.

  In the camshaft device according to the first embodiment configured as described above, the oil supplied from the hydraulic pressure supply source is the oil hole 7 of the cap member 5 of the first journal 10 and the oil hole 45 of the outer ring 42 of the rolling bearing 40. And then flows into the communication passage 65 in the rolling bearing 40 and then flows into the oil passage 25 on the camshaft 20 side. The timing gear 33 and the camshaft 20 are relatively rotationally controlled (advance control or retard control) by the oil supplied from the oil passage 25 to the variable valve timing mechanism 31.

As shown in FIG. 2, the communication passage 65 in the rolling bearing 40 is defined by annular seal members 60 and 61 that are spaced apart from each other by a predetermined interval in the axial direction between the double rows of balls 55 and 57. Therefore, the oil that has flowed into the communication passage 65 in the rolling bearing 40 can be prevented from leaking out toward the double-row balls 55 and 57 by the two seal members 60 and 61.
As a result, the oil flowing into the communication passage 65 in the rolling bearing 40 can be satisfactorily guided to the oil passage 25 on the camshaft 20 side while suppressing a decrease in hydraulic pressure, and is supplied to the variable valve timing mechanism 31 at the end of the camshaft 20. Oil can be supplied without deficiency, and a problem that the rolling resistance of the double-row balls 55 and 57 is increased by the oil leaking to the double-row balls 55 and 57 can be prevented.
Even if the oil that has flowed into the communication path 65 leaks toward the double rows of balls 55 and 57, this oil can be kept to a small amount, and a small amount of oil can serve as the lubricating oil for the double rows of balls 55 and 57. Works.

In the first embodiment, the oil is supplied to the variable valve timing mechanism 31 through the rolling bearing 40 of the first journal 10 disposed in the vicinity of the variable valve timing mechanism 31. The path 25 can be shortened.
Further, in the first embodiment, as shown in FIGS. 2 and 3, the oil passage 25 on the camshaft 20 side is provided with a groove 28 recessed in the axial direction of the outer peripheral surface of the camshaft 20 and an inner ring body 50. A horizontal hole 27 formed in cooperation with the peripheral surface, and a vertical hole 26 penetrating in the radial direction of the inner ring body 50, having an outer end opening in the communication path 65 and an inner end opening in the horizontal hole 27. And is configured.
For this reason, even when the outer diameter of the shaft portion of the camshaft 20 with respect to the first journal 10 is formed small, the oil passage 25 can be easily formed, and the outer diameter of the outer ring body 42 of the rolling bearing 40 can be increased by this amount. It is possible to reduce the size by reducing the size.
Further, the lateral hole 27 of the oil passage 25 can be formed by a groove process that is easier to process than the hole process.

  Further, in the first embodiment, the outer diameter portions of the annular seal members 60 and 61 are fitted and disposed in the annular grooves 46 and 47 on the inner peripheral surface of the outer ring body 42. Unexpected misalignment in the axial direction of both annular seal members 60 and 61 can be prevented. For this reason, the communication path 65 can be kept in the partitioned state by the annular seal members 60 and 61.

Next, a camshaft device according to Embodiment 2 of the present invention will be described with reference to FIGS.
As shown in FIGS. 4 to 6, in the second embodiment, the camshaft 120 is fitted to a shaft main body 120a having a plurality of cams 121 arranged on the axis at predetermined intervals, and the shaft main body 120a. And an end shaft portion 120b fixed integrally with each other.
And the rolling bearing 140 corresponding to the 1st journal 110 is arrange | positioned at the outer peripheral surface of the end shaft part 120b.
The rolling bearing 140 includes an outer ring body 142, an end shaft portion 120 b that functions as an inner ring body, double-row balls 155 and 157 as rolling elements, and cages 156 and 158.
That is, the inner ring raceways 151 and 152 facing the double rows of balls 155 and 157 are formed on the outer peripheral surface of the end shaft portion 120b as the inner ring body at a predetermined distance in the axial direction.
Further, both outer ring raceway surfaces 143 and 144 corresponding to the both inner ring raceway surfaces 151 and 152 are formed on the inner peripheral surface of the outer ring body 142.
Between the inner raceway surfaces 151 and 152 and the outer raceway surfaces 143 and 144, double rows of balls 155 and 157 are assembled so as to be able to roll while being held by the cages 156 and 158. .

Further, as shown in FIG. 5, oil holes 145 are formed in the radial direction in the portion located at the intermediate portion between both outer ring raceway surfaces 143 and 144 of the outer ring body 142 in substantially the same manner as in the first embodiment. . The oil hole 145 has an outer end that opens to the outer peripheral surface of the outer ring body 142 and communicates with the oil hole 7 of the cap member 5, and an inner end that opens to the inner peripheral surface of the outer ring body 142.
An oil hole 145 of the outer ring body 142 is camped in a portion located between the double row balls 155 and 157 between the outer peripheral surface of the end shaft portion 120b as the inner ring body and the inner peripheral surface of the outer ring body 142. A communication passage 165 that communicates with the oil passage 125 on the shaft 120 side is defined by annular seal members 160 and 161 that are spaced apart from each other in the same axial direction as in the first embodiment.

Further, in the second embodiment, the oil passage 125 on the camshaft 120 side includes a horizontal hole 127 that is drilled in the axial direction from one end of the end shaft portion 120b, and a deep hole in the horizontal hole 127 from the outer peripheral surface of the end shaft portion 120b. A vertical hole 126 formed in communication with the side end portion is provided, and the vertical hole 126 communicates with the communication path 165.
Since the other configuration of the second embodiment is configured in the same manner as the first embodiment, the same components are denoted by the same reference numerals and the description thereof is omitted.

In the camshaft device according to the second embodiment configured as described above, similarly to the first embodiment, the communication path 165 in the rolling bearing 140 is axially disposed between the double-row balls 155 and 157. Since both of the seal members 160 and 161 are separated by a predetermined interval, the two seal members prevent oil flowing into the communication passage 165 in the rolling bearing 140 from leaking toward the double-row balls 155 and 157. 160 and 161 can prevent this.
As a result, the oil flowing into the communication passage 165 in the rolling bearing 140 can be favorably guided to the oil passage 125 on the camshaft 120 side while suppressing a decrease in hydraulic pressure, and the variable assembled to the end shaft portion 120b of the camshaft 120. Oil can be supplied to the valve timing mechanism 31 without a shortage, and a problem that the rolling resistance of the double row balls 155 and 157 is increased by the oil leaking to the double row balls 155 and 157 is also prevented. be able to.
Even if the oil that has flowed into the communication path 165 leaks toward the double-row balls 155 and 157, the oil can be kept to a small amount, and a small amount of oil can serve as the lubricating oil for the double-row balls 155 and 157. Works.

  In particular, in the second embodiment, since the end shaft portion 120b of the camshaft 120 functions as an inner ring body of the rolling bearing 140, it is possible to reduce the number of parts and the number of assembling steps.

Next, a camshaft device according to Embodiment 3 of the present invention will be described with reference to FIG.
As shown in FIG. 7, in the third embodiment, an advance oil path and a retard oil path are independently configured in the rolling bearing 240 corresponding to the first journal.
In other words, an advance oil hole 245a and a retard oil hole 245b are respectively formed in the radial direction at a portion of the outer ring body 242 of the rolling bearing 240 located in the middle of both outer ring raceway surfaces 243 and 244. ing. The outer ends of these oil holes 245a and 245b open to the outer peripheral surface of the outer ring body 242, and communicate with the advance oil hole and the retard oil hole (not shown) of the cap member, respectively. The end opens on the inner peripheral surface of the outer ring body 242.
Oil holes 245a and 245b of the outer ring body 242 are provided on the camshaft in a portion located between the double row balls 255 and 257 as rolling elements between the outer circumferential surface of the inner ring body 250 and the inner circumferential surface of the outer ring body 242. An advance communication passage 265a and a retard communication passage 265b that communicate with the advance oil passage 225a and the retard oil passage 225b on the 220 side are respectively annularly spaced apart by a predetermined distance in the axial direction. The seal members 260a, 260b, 261a, and 261b are partitioned.
Since other configurations of the third embodiment are configured in the same manner as the first embodiment, description thereof is omitted.

  In the camshaft device according to the third embodiment configured as described above, the oil supplied from the hydraulic supply source via the control valve is the oil hole for the advance angle of the cap member of the first journal and the rolling bearing 240. After passing through the oil hole 245b for lagging or 245a and flowing into the communication passage 265a for advancement or the communication passage 265b for retarding in the rolling bearing 240, the oil passage 225a for advancement on the camshaft 220 side. Or it flows to the oil passage 225b for retarding angle. The timing gear and the camshaft 220 are controlled to rotate relative to each other by the oil supplied from the advance oil passage 225a or the retard oil passage 225b to the advance chamber or retard chamber of the variable valve timing mechanism. (Advance control or retard control).

The advance communication passage 265a and the retard communication passage 265b in the rolling bearing 240 are annular seal members 260a, 261a, 260b that are spaced apart in the axial direction between the double rows of balls 255, 257, respectively. Since each of the seals 261b is partitioned, the oil flowing into the advance communication passage 265a or the retard communication passage 265b in the rolling bearing 240 leaks toward the double rows of balls 255, 257. This can be prevented by the members 260a, 261a, 260b, and 261b.
As a result, the oil that has flowed into the advance communication passage 265a or the retard communication passage 265b in the rolling bearing 240 while suppressing a decrease in hydraulic pressure is used as the advance oil passage 225a or retard on the camshaft 220 side. The oil passage 225b can be satisfactorily guided, and oil can be supplied to the advance chamber or the retard chamber of the variable valve timing mechanism 231 assembled to the camshaft 220 without a shortage, and the double row balls 255, 257 can be supplied. In addition, it is possible to prevent a problem that the rolling resistance of the double-row balls 255 and 257 is increased by the oil leaking out.
Even if the oil that has flowed into the advance communication passage 265a or the retard communication passage 265b leaks toward the double rows of balls 255, 257, this oil can be suppressed to a small amount. Acts as a lubricating oil for the double row balls 255, 257.

Next, a camshaft device according to Embodiment 4 of the present invention will be described with reference to FIG.
As shown in the figure, in Example 4, a double row rolling bearing 340 corresponding to the first journal is constituted by a double row roller bearing.
That is, in the fourth embodiment, the double row rolling bearing 340 includes an outer ring body 342, an inner ring body 350, double row rollers 355 and 357 as rolling elements, and cages 356 and 358.
Since other configurations of the fourth embodiment are configured in the same manner as the third embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.
Therefore, this fourth embodiment also has the same effects as the third embodiment.

Next, a camshaft device according to Embodiment 5 of the present invention will be described with reference to FIG.
As shown in FIG. 9, in the fifth embodiment, a double row rolling bearing 440 corresponding to the first journal is constituted by a combination of a ball bearing and a bearing that form a double row.
That is, in the fifth embodiment, the double row rolling bearing 440 includes an outer ring body 442, an inner ring body 450, a double row ball 455 as a rolling element, rollers 457, and cages 456 and 458. ing.
Since other configurations of the fifth embodiment are configured in the same manner as the third embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.
Therefore, the fifth embodiment has the same operational effects as the third embodiment.

In addition, this invention is not limited to the said Examples 1-5, In the range which does not deviate from the summary of this invention, it can implement with a various form.
For example, in the first to fifth embodiments, the case where the cam journal is the first journal 10 is illustrated, but the present invention can be implemented when a hydraulic path is provided for cam journals other than the first journal 10.
Moreover, in the said Examples 1-5, although the case where the assembly | attachment components assembled | attached to the one end part of the camshaft 20 (120,220) was the variable valve timing mechanism 31, hydraulic pressures other than the variable valve timing mechanism 31 were illustrated. The present invention can also be carried out when oil is supplied to the device, and also when oil is supplied to the rolling bearings of other cam journals.

1 Cylinder head 5 Cap member 10 No. 1 journal (cam journal)
20, 120, 220 Camshaft 25 Oil passage 31 Variable valve timing mechanism (assembled parts)
40 Rolling bearing 42 Outer ring body 45 Oil hole 46, 47 Annular groove 50 Inner ring body 60, 61, 160, 161, 260a, 261a, 260b, 261b Seal member 65, 165 265a, 265b Communication path

Claims (3)

A camshaft device that supplies oil to an assembly part that is assembled to the camshaft through a cam journal that rotatably supports the camshaft,
The cam journal is provided with a rolling bearing for the camshaft,
An oil hole leading to a hydraulic pressure supply source is formed in the outer ring body of the rolling bearing,
Between the outer peripheral surface of the inner ring body of the rolling bearing and the inner peripheral surface of the outer ring body, a communication path that connects the oil hole to the oil path on the camshaft side is disposed at a predetermined interval in the axial direction. A camshaft device characterized in that the camshaft is defined by both annular seal members. The camshaft device according to claim 1,
Assembly parts are variable valve timing mechanism,
The cam journal is the first journal arranged in the vicinity of the variable valve timing mechanism,
Rolling bearings have double row rolling elements,
The camshaft device is characterized in that the communication path is defined by both annular seal members spaced apart in the axial direction between the double row rolling elements. The camshaft device according to claim 2,
On the inner peripheral surface located between the outer ring raceway surfaces of the double row of the outer ring body, both annular grooves that are spaced apart in the axial direction are formed, respectively.
The cam shaft device is characterized in that both annular seal members are arranged with their respective outer diameter portions fitted into the annular grooves.

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