JP2008057737A - Roller bearing, camshaft support structure and internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roller bearing having a simple structure capable of preventing an outer ring from rotating within a housing. <P>SOLUTION: A needle roller bearing 21 as the roller bearing includes the outer ring 22 having outer ring members 22a, 22b split by a split line extending axially in the bearing and also includes needle rollers 23 as rollers arranged along a raceway surface of the outer ring 22. The outer ring member 22a keeps an engagement claw 22c that engages with the housing located only at one end in the circumference. The annular outer ring 22 is formed by continuously connecting the two outer ring members 22a, 22b in the circumferential direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a roller bearing that supports a camshaft, a crankshaft, a rocker shaft, and the like for an automobile engine, a camshaft support structure that employs a roller bearing, and an internal combustion engine.

  A conventional bearing that supports a camshaft of an automobile engine is described in, for example, Japanese Patent Application Laid-Open No. 2005-90696 (Patent Document 1). Referring to FIG. 17, the camshaft 101 described in the publication has a cam lobe 101a, a cylindrical journal portion 101b supported by a roller bearing 102, and an end large-diameter portion 101c. .

  Here, the outer diameter of the journal portion 101b is smaller than the maximum outer diameter of the cam lobe 101a and the outer diameter of the large end portion 101c. For this reason, the roller bearing 102 disposed in the journal portion 101 b and rotatably supporting the camshaft 101 cannot be inserted from the axial direction of the camshaft 101.

  Accordingly, the roller bearing 102 is substantially divided into a plurality of rollers 103, a substantially semi-cylindrical holding body 104, 105 divided in the circumferential direction, and a circumferential direction divided between the cylinder head 108 and the cap 109. Semi-cylindrical lace plates 106 and 107 are provided. Referring to FIG. 18, the lace plate 107 has two protrusions 107a projecting radially outward at both ends in the circumferential direction, and the cap 109 has a recess 109a corresponding to the protrusion 107a.

Further, it is described that by engaging the protrusion 107a and the recess 109a, relative movement in the circumferential direction and the axial direction between the race plate 107 and the cap 109 can be prohibited when the roller bearing 102 rotates. Has been. The configuration between the race plate 106 and the cylinder head 108 is similar.
Japanese Patent Laid-Open No. 2005-90696

  In the roller bearing 102 described in the above publication, the protrusion 107a is formed by pushing the outer diameter surface by applying a radially outward force to the inner diameter surface of the race plate 107. As a result, a recess is formed on the inner diameter surface of the race plate 107 that becomes the raceway surface of the roller 103. This causes vibrations to occur when the roller 103 passes over the indentation, and causes the roller 103 to rotate smoothly, such as the surface of the roller 103 peeling off early.

  This problem can occur not only in the roller bearing that supports the camshaft but also in the bearing that supports the crankshaft and the rocker shaft.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a roller bearing that supports a camshaft or the like of an automobile engine and that can prevent the outer ring from rotating in the housing using a simple structure.

  Furthermore, it is an object of the present invention to provide a camshaft support structure and an internal combustion engine that are excellent in durability and reliability by adopting such a roller bearing as a bearing for supporting a camshaft.

  A roller bearing according to the present invention includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in a circumferential direction, and a plurality of rollers disposed along an inner diameter surface of the outer ring. And an outer ring member has an engagement piece which engages with a housing only in one side edge part among the both-sides edge parts of the circumference direction.

  By dividing the outer ring into a plurality of outer ring members as in the above configuration, the bearing can be applied to a place where the bearing cannot be inserted from the axial direction, such as a camshaft. Further, by providing the engagement piece that engages with the housing, it is possible to prevent the outer ring from rotating within the housing when the bearing rotates.

  Further, in order to prevent the rotation of each outer ring member, it is only necessary to provide an engagement piece that engages with the housing only at one end portion in the circumferential direction. In this way, by reducing the positions where the engagement pieces are provided, the recess of the raceway surface is reduced and the rotation of the rollers is stabilized, and the manufacturing cost can be reduced and the product cost can be reduced.

  Preferably, the engagement piece is an engagement claw in which one end portion in the circumferential direction of the outer ring member is bent radially outward. By thus bending the circumferential end of the outer ring member radially outward to form the engaging claw, the inner diameter surface of the outer ring member serving as the raceway surface of the roller can be kept smooth. As a result, a roller bearing in which the rollers can rotate smoothly can be obtained.

  The camshaft support structure according to the present invention includes a camshaft, a housing that houses the camshaft, and a roller bearing that rotatably supports the camshaft with respect to the housing. When paying attention to the roller bearing, it includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in the circumferential direction, and a plurality of rollers disposed along the inner diameter surface of the outer ring. And an outer ring member has an engagement piece which engages with a housing only in one side edge part among the both-sides edge parts of the circumference direction.

  An internal combustion engine according to the present invention includes a housing, a cylinder provided in the housing, a valve for opening and closing an intake passage and an exhaust passage communicating with the cylinder, a camshaft for controlling timing of opening and closing the valve, and a camshaft. And a roller bearing that is rotatably supported. When paying attention to the roller bearing, it includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in the circumferential direction, and a plurality of rollers disposed along the inner diameter surface of the outer ring. And an outer ring member has an engagement piece which engages with a housing only in one side edge part among the both-sides edge parts of the circumference direction.

  Adopting a roller bearing that prevents the outer ring from rotating in the housing and smoothly rotates the roller as a bearing that rotatably supports the camshaft, as described above, provides excellent durability and reliability. High camshaft support structure and internal combustion engine can be obtained.

  According to this invention, it is possible to obtain a roller bearing in which the outer ring is prevented from rotating in the housing and the rollers can rotate smoothly. In addition, by adopting such a roller bearing as a bearing for supporting the camshaft, it is possible to obtain a camshaft support structure and an internal combustion engine that have excellent durability and high reliability.

  An internal combustion engine 11 according to an embodiment of the present invention will be described with reference to FIGS. 9 is a cross-sectional view showing one of the cylinders of the internal combustion engine 11 according to one embodiment of the present invention, and FIG. 10 is a view showing a camshaft 19 used in the internal combustion engine 11.

  First, referring to FIG. 9, the internal combustion engine 11 performs a cylinder block 12 and a cylinder head 13 as a housing, a motion conversion mechanism that converts reciprocating motion into rotational motion, and intake of air-fuel mixture and exhaust of combustion gas. A reciprocating engine including an air supply / exhaust mechanism and a spark plug 20 as an ignition device.

  The motion conversion mechanism is housed in the cylinder block 12 and is transmitted through a piston 14 that reciprocates inside a cylinder 12a provided in the cylinder block 12, and a flywheel (not shown) or a clutch (not shown). A crankshaft 15 connected to (not shown), a connecting rod 16 having one end connected to the piston 14 and the other end connected to the crankshaft 15 to convert the reciprocating motion of the piston 14 into the rotational motion of the crankshaft 15; Is provided.

  The air supply / exhaust mechanism is formed in the cylinder head 13 and communicates with the cylinder 12a, the intake passage 13a and the exhaust passage 13b, the intake valve 17 as a valve disposed between the cylinder 12a and the intake passage 13a, the cylinder 12a and the exhaust passage. An exhaust valve 18 as a valve disposed between the passages 13b, and an intake valve 17 and a camshaft 19 for controlling the opening / closing timing of the exhaust valve 18 are provided.

  The intake valve 17 includes a valve stem 17a, a valve head 17b provided at one end of the valve stem 17a, and a valve spring 17c that urges the intake valve 17 in a direction to close the intake passage 13a. A camshaft 19 is connected to the other end portion of the stem 17a. The exhaust valve 18 has the same configuration as the intake valve 17 and will not be described.

  Referring to FIG. 10, cam shaft 19 used in internal combustion engine 11 includes a shaft portion 19a and a plurality of cams 19b. The shaft portion 19a is rotatably supported by a needle roller bearing 21 according to an embodiment of the present invention described later. The camshaft 19 is connected to the crankshaft 15 by a timing belt (not shown), and rotates as the crankshaft 15 rotates.

  Since the cam 19b is connected to the intake valve 17 or the exhaust valve 18, respectively, the same number as the valves 17 and 18 is provided. Further, as shown in FIG. 9, the cam 19 b includes a long diameter portion 19 c having a relatively large diameter and a short diameter portion 19 d having a relatively small diameter. The position of the long diameter portion 19c is shifted in the circumferential direction. This makes it possible to open and close the valves 17 and 18 connected to the plurality of cams 19b at different timings.

  The internal combustion engine 11 is a DOHC (Double Over Head Camshaft) engine in which the camshaft 19 is disposed on the upper side of the cylinder head 13 and provided on the intake valve 17 side and the exhaust valve 18 side, respectively.

  Next, the operating principle of this internal combustion engine will be described.

  First, in the internal combustion engine 11, if the process of moving the piston 14 between the position where the piston 14 is most elevated (top dead center) and the position where the piston 14 is most lowered (bottom dead center) is defined as one process, This is a four-cycle engine comprising four steps of a compression step, a combustion step, and an exhaust step.

  In the intake process, the piston 14 moves from the top dead center to the bottom dead center with the intake valve 17 open and the exhaust valve 18 closed. As a result, the volume inside the cylinder 12a (referring to the space above the piston 14, hereinafter the same) increases and the internal pressure decreases, so the air-fuel mixture flows from the intake passage 13a into the cylinder 12a. The air-fuel mixture refers to a mixture of air (oxygen) and gasoline in a mist form.

  In the compression process, the piston 14 moves from the bottom dead center to the top dead center with the intake valve 17 and the exhaust valve 18 closed. As a result, the internal volume of the cylinder 12a decreases and the internal pressure increases.

  In the combustion process, the spark plug 20 is ignited with the intake valve 17 and the exhaust valve 18 closed. As a result, the air-fuel mixture in the compressed state expands abruptly by burning, and pushes down the piston 14 from the top dead center to the bottom dead center. By transmitting this force to the crankshaft 15 through the connecting rod 16 as a rotational motion, a driving force is generated.

  In the exhaust process, the piston 14 moves from the bottom dead center to the top dead center with the intake valve 17 closed and the exhaust valve 18 opened. As a result, the volume inside the cylinder 12a is reduced and the combustion gas flows out to the exhaust passage 13b. In this process, after the piston 14 reaches the top dead center, the process returns to the intake process.

  In each of the above steps, “the state in which the intake valve 17 is open” means that the long diameter portion 19c of the cam 19b is in contact with the intake valve 17 and the intake valve 17 is pushed downward against the valve spring 17c. The state where the intake valve 17 is closed is a state in which the short diameter portion 19d of the cam 19b is in contact with the intake valve 17 and the intake valve 17 is pushed upward by the restoring force of the valve spring 17c. Point to. Further, since the same applies to the exhaust valve 18, the description thereof is omitted.

  In each of the above processes, the driving force is generated only in the combustion process, and in the other processes, the piston 14 reciprocates by the driving force generated in the other cylinders. Therefore, from the viewpoint of maintaining smooth rotation of the crankshaft 15, it is desirable to shift the timing of the combustion stroke with a plurality of cylinders.

  Next, with reference to FIGS. 1-8, the needle roller bearing 21 as a roller bearing which concerns on one Embodiment of this invention, and the camshaft support structure using this needle roller bearing 21 are demonstrated. 1, FIG. 7 and FIG. 8 are views showing states before and after the camshaft support structure according to one embodiment of the present invention is assembled, and FIGS. 2 to 6 are needle roller bearings according to one embodiment of the present invention. It is a figure which shows each component of 21.

  First, referring to FIG. 1, a camshaft support structure according to an embodiment of the present invention includes a camshaft 19, a cylinder head 13 and a bearing cap 13 c as a housing for housing the camshaft 19, and the camshaft 19. And a needle roller bearing 21 that rotatably supports the housing.

  The needle roller bearing 21 includes an outer ring 22 formed by connecting a plurality of arc-shaped outer ring members 22 a and 22 b in the circumferential direction, and a needle roller 23 as a plurality of rollers disposed along the inner diameter surface of the outer ring 22. And a cage 24 having a parting line extending in the axial direction of the bearing at one place on the circumference and holding the intervals between the plurality of needle rollers 23.

  As a bearing for supporting the camshaft 19, a needle roller bearing 21 is generally employed. The needle roller bearing 21 has an advantage that a high load capacity and high rigidity can be obtained for a small bearing projection area because the needle roller 23 and the raceway surface are in line contact. Therefore, it is preferable in that the thickness dimension in the radial direction of the shaft portion 19b can be reduced while maintaining the load capacity.

  The outer ring member 22a will be described with reference to FIGS. 2 is a side view of the outer ring member 22a, FIG. 3 is a view of FIG. 2 viewed from the III direction, and FIG. 4 is a view of FIG. 2 viewed from the IV direction. Further, since the outer ring member 22b has the same shape as the outer ring member 22a, description thereof is omitted.

  First, referring to FIG. 2, the outer ring member 22 a has a semicircular shape with a central angle of 180 °, and is engaged with the cylinder head 13 only at one side end portion among both side end portions in the circumferential direction. There are engaging claws 22c as engagement pieces bent radially outward, and flanges 22d that protrude radially inward at both axial ends and restrict movement of the retainer 24 in the axial direction. The two outer ring members 22a and 22b are connected in the circumferential direction to form an annular outer ring 22. The central portion in the axial direction of the inner diameter surface of the outer ring 22 functions as a raceway surface of the needle rollers 23.

  Also, referring to FIG. 3, two engaging claws 22c are provided at both ends in the axial direction at one end in the circumferential direction of the outer ring member 22a, and between the two engaging claws 22c. Is formed with a substantially V-shaped recess 22e recessed in the circumferential direction. The two engaging claws 22c are disposed on both ends and on a straight line parallel to the rotational axis of the needle roller bearing 21 so as to avoid the axial central portion serving as the raceway surface of the outer ring member 22a. Preferably, the length L between the two engaging claws 22c is set to be longer than the effective length l of the needle roller 23. In the present specification, the “effective length of the roller” refers to a length obtained by removing the length of the chamfered portions at both ends from the roller length.

  Further, referring to FIG. 4, at the other circumferential end of outer ring member 22a, two flat portions 22f having the same width as the axial width of engagement claw 22c are provided at two axial ends and two flat portions. Between the portions 22f, a substantially V-shaped convex portion 22g having a circular arc tip and protruding in the circumferential direction is provided. The concave portion 22e receives the convex portion 22g of the adjacent outer ring member when the outer ring members 22a and 22b are connected in the circumferential direction.

  Further, referring to FIGS. 3 and 4, an oil hole 22 h that penetrates from the radially outer side to the radially inner side is provided on the outer diameter surface of the outer ring member 22 a. The oil hole 22h is provided at a position corresponding to an oil passage (not shown) provided in the housing, and supplies lubricating oil into the needle roller bearing 21. Note that the size, position, and number of the oil holes 22h depend on the size, position, and number of oil passages provided in the housing.

  The outer ring member 22a having the above configuration is a shell outer ring formed by pressing a steel plate such as carbon steel. Specifically, after the overall shape of the outer ring member 22a and the engaging claws 22c and the flange portion 22d are formed by press working, heat treatment is performed to obtain predetermined mechanical properties such as hardness to obtain a finished product. .

  Next, the cage 24 will be described with reference to FIGS. 5 and 6. 5 is a side view of the cage 24, and FIG. 6 is a partial cross-sectional view including a divided portion of the cage 24. Referring to FIGS. 5 and 6, the retainer 24 has a substantially C shape having a parting line extending in the axial direction of the bearing at one place on the circumference, and a pocket 24 c that accommodates the needle rollers 23. It is provided at equal intervals in the circumferential direction. The cage 24 is formed by injection molding of a resin material.

  The cut end surface 24a on one side in the circumferential direction of the divided portion is provided with a recess 24d, and the cut end surface 24b on the other side is provided with a protrusion 24e corresponding to the recess 24d, and the recess 24d and the protrusion 24e are engaged. By combining, an annular retainer 24 can be obtained. In this embodiment, the width of the tip portion of the convex portion 24e is set larger than that of the root portion, and the width of the opening portion of the concave portion 24d is set smaller than that of the innermost portion. Thereby, the engagement between the concave portion 24d and the convex portion 24e is ensured.

  In the needle roller bearing 21 configured as described above, since the engaging claw 22c engages with the housing, the outer ring 22 can be reliably prevented from rotating within the housing during rotation of the bearing. Further, since the engaging claws 22c are formed by bending the circumferential end portions of the outer ring members 22a and 22b radially outward by bending, the raceway surface can be kept smooth. As a result, the needle rollers 23 can smoothly rotate on the raceway surface.

  Furthermore, by providing the engaging claw 22c at a position deviated from the raceway surface of the outer ring member 22a, the influence of minute deformation of the outer ring members 22a and 22b on the rotation of the needle roller 23 due to bending of the engaging claw 22c or the like. Can be minimized. As a result, the needle roller 23 rotates more smoothly.

  Next, a procedure for incorporating the needle roller bearing 21 into the camshaft 19 will be described with reference to FIGS.

  First, the needle rollers 23 are incorporated in the pockets 24 c of the cage 24. Next, using the elasticity of the cage 24, the divided portion is expanded and assembled into the camshaft 19. Further, the concave portion 24d and the convex portion 24e are engaged so that the retainer 24 does not come off.

  Next, on the cylinder head 13, the outer ring member 22a on one side, the cam shaft 19 incorporating the retainer 24, the outer ring member 22b on the other side, and the bearing cap 13c are assembled in this order, and the cylinder head 13 and the bearing cap 13c Is fixed with bolts. At this time, it arrange | positions so that the recessed part 22e of the outer ring member 22a, the convex part 22g of the outer ring member 22b, and the convex part 22g of the outer ring member 22a and the recessed part 22e of the outer ring member 22b may each face | match.

  Further, the engaging claw 22c of the outer ring member 22a is arranged to engage with the engaging groove 13d provided on the contact surface of the cylinder head 13 with the bearing cap 13c, and the engaging claw 22c of the outer ring member 22b is The bearing cap 13c is disposed so as to engage with an engaging groove 13d provided on the contact surface of the bearing cap 13c with the cylinder head 13. As a result, the outer ring members 22a and 22b can be prevented from rotating inside the housing during bearing rotation.

  Here, the abutting surface of the cylinder head 13 and the bearing cap 13c is generally a surface parallel to the axial direction of the camshaft 19, that is, the rotational axis of the bearing. Therefore, by disposing the two engaging claws 22c provided at the circumferential ends of the outer ring members 22a and 22b in a straight line parallel to the rotational axis of the needle roller bearing 21, the engaging claws 22c are connected to the cylinder head 13. And the bearing cap 13c.

  By using the above assembling procedure, the camshaft 19, the outer ring 22, the cage 24, and the housing are arranged concentrically, and the needle roller bearing 21 in which the needle roller 23 can rotate stably is obtained. Can do. Further, the needle roller bearing 21 having the above configuration is incorporated from the radial direction of the support portion by dividing the outer ring 22 into two outer ring members 22a and 22b and dividing the cage 24 at one place in the circumferential direction. Therefore, it can be employed as a bearing that supports the shaft portion 19b of the camshaft 19.

  The abutting portions of the outer ring members 22a and 22b are desirably arranged in the non-load region when the camshaft 19 is divided into a load region and a non-load region in the circumferential direction. The abutting portions of the outer ring members 22a and 22b are provided with a certain gap in the circumferential direction and the axial direction in consideration of expansion due to temperature rise. Therefore, when the abutting portion is disposed in the load region, smooth rotation of the needle roller 23 passing through the abutting portion may be hindered.

  In the present specification, the “load region” refers to a region where a relatively large load is applied in the circumferential direction of the outer ring members 22a and 22b. Further, the “non-load region” refers to a region where only a relatively small load is applied in the circumferential direction of the outer ring members 22a and 22b.

  In the above embodiment, an example in which the needle roller bearing 21 is employed as a bearing for supporting the camshaft 19 has been shown. However, the present invention is also applicable to other roller bearings such as a cylindrical roller bearing and a rod roller bearing. can do.

  Moreover, although the needle roller bearing 21 in said embodiment showed the example containing the outer ring | wheel 22, the needle roller 23, and the holder | retainer 24, it is not restricted to this, All the rollers which omitted the holder | retainer 24 were shown. It may be a type of roller bearing.

  Moreover, although the outer ring | wheel 22 in said embodiment showed the example divided | segmented into the outer ring members 22a and 22b in two places of the circumferential direction, it is possible to divide into arbitrary numbers without restricting to this. For example, the outer ring may be formed by connecting three outer ring members having a central angle of 120 ° in the circumferential direction. Furthermore, an annular outer ring may be formed by combining a plurality of outer ring members having different central angles. Similarly, the cage 24 can be of any form.

  Moreover, although the outer ring member 22a in the above embodiment is an example of a shell outer ring manufactured by pressing a steel plate, the outer ring member 22a is not limited to this and may be a machined outer ring manufactured by cutting. In addition, the cage 24 in the above embodiment is an example of a resin cage having high production efficiency and high elastic deformability. However, the cage is not limited to this and may be a machined cage by cutting. Alternatively, it may be a press cage obtained by pressing a steel plate.

  Moreover, although the engagement claw 22c in the above embodiment is formed by bending the circumferential ends of the outer ring members 22a and 22b outward in the radial direction, the present invention is not limited thereto and can be engaged with the housing. It can be set as the engagement piece of arbitrary shapes.

  Moreover, although the engagement claw 22c in said embodiment showed the example provided in two places of the axial direction both ends, it should just be provided at least one place in arbitrary positions, without restricting to this. For example, you may provide only in one place of the one side edge part of an axial direction, and you may provide only in one place of the axial direction center part.

  Moreover, although the collar part 22d in said embodiment showed the example provided in the circumferential direction whole region of the outer ring members 22a and 22b, it provided not only in this but partially provided in a part of the circumferential direction. Also good. At that time, the location and number of the buttocks can be arbitrarily set, but it is desirable that they are arranged in the non-load region when incorporated in the camshaft 19.

  The needle roller bearing 21 in the above embodiment can be widely used not only as a bearing that supports the camshaft 19 but also as a bearing that supports a crankshaft, a rocker shaft, and the like.

  Further, the internal combustion engine 11 in the above embodiment shows an example of the DOHC system in which the camshaft 19 is provided on each of the intake valve 17 side and the exhaust valve 18 side, and the cam 19b is directly connected to the valves 17 and 18. However, the present invention is not limited to this, and a single camshaft (SOHC) system in which one camshaft is connected to an intake valve and an exhaust valve via a rocker arm may be used. An OHV (Over Head Valve) system that is arranged and connected to a valve via a push rod and a rocker arm may be used.

  Furthermore, the present invention is not limited to the internal combustion engine 11 in the above embodiment, and can be applied to any form of internal combustion engine having a camshaft. The present invention can also be applied to a single-cylinder internal combustion engine. However, like a shaft portion 19b of a camshaft 19 employed in a multi-cylinder engine as shown in FIG. It is suitable as a bearing for supporting a portion where 21 cannot be inserted.

  In the above embodiment, the example of the engaging claw 22c bent outward in the radial direction is shown as an example of the engaging piece of the outer ring member 22a, 22b. Any form that can prevent rotation of the member can be employed. For example, a needle roller bearing 31 according to another embodiment of the present invention will be described with reference to FIGS. 11, FIG. 15 and FIG. 16 are views showing states before and after the camshaft support structure according to another embodiment of the present invention is assembled, and FIGS. 12 to 14 are outer ring members according to other embodiments of the present invention. It is a figure which shows 32a. Further, since the basic configuration of the needle roller bearing 31 is the same as that of the needle roller bearing 21, the description of the common points is omitted, and the difference will be mainly described.

  First, referring to FIG. 11, needle roller bearing 31 is arranged along outer ring 32 formed by connecting a plurality of arc-shaped outer ring members 32 a and 32 b in the circumferential direction, and the inner diameter surface of outer ring 32. A plurality of needle rollers 33 and a retainer 34 having a parting line extending in the axial direction of the bearing at one place on the circumference and holding the interval between the plurality of needle rollers 33, and housing the camshaft 19 13 is supported rotatably.

  The outer ring member 32a has a semicircular shape with a central angle of 180 °, and has an engagement piece 32c that engages with the cylinder head 13 at one end portion in the circumferential direction, and projects radially inward at both axial end portions. And a flange 32d for restricting movement of the retainer 34 in the axial direction. Since the outer ring member 32b has the same configuration, the description thereof is omitted.

  The engagement piece 32c protrudes in a tangential direction at one end portion in the circumferential direction of the outer ring member 32a. Moreover, it arrange | positions from the axial direction center part of the outer ring member 32a used as the track surface of the needle roller 33, ie, the axial direction both ends of the outer ring member 32a.

  Further, referring to FIGS. 15 and 16, when the needle roller bearing 31 having the above configuration is incorporated in the camshaft 19, the engaging piece 32c of the outer ring member 32a is located on the other circumferential side of the adjacent outer ring member 32b. It engages with the engaging groove 13d of the housing 13 so as to cover the outer diameter surface of the end portion. The same applies to the engagement piece 32c of the outer ring member 32b.

  By setting it as the said structure, it can prevent that the outer ring members 32a and 32b rotate within the housings 13 and 13a. Further, since bending is not required to form the engagement pieces 32c at the circumferential ends of the outer ring members 32a and 32b, the outer ring member 32a that becomes the raceway surface of the needle rollers 33 by the formation of the engagement pieces 32c. , 32b is not deformed. As a result, the needle roller bearing 31 in which the needle roller 33 can rotate smoothly can be obtained.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The present invention is advantageously used for a roller bearing that supports a camshaft of an automobile engine, a camshaft support structure, and an internal combustion engine.

It is a figure which shows the state before the assembly of the camshaft support structure which concerns on one Embodiment of this invention. It is a figure which shows the outer ring member of the roller bearing which concerns on one Embodiment of this invention. It is the figure seen from the III direction of FIG. It is the figure seen from the IV direction of FIG. It is a figure which shows the side view of the holder | retainer of the roller bearing which concerns on one Embodiment of this invention. It is a fragmentary sectional view containing the division | segmentation part of the holder | retainer of FIG. It is sectional drawing which looked at the state after the incorporation of the camshaft support structure of FIG. 1 from the axial direction. It is sectional drawing which looked at the state after the incorporation of the camshaft support structure of FIG. 1 from the radial direction. It is sectional drawing which shows one cylinder of the internal combustion engine which concerns on one Embodiment of this invention. It is a figure which shows the camshaft employ | adopted as the internal combustion engine of FIG. It is a figure which shows the state before the assembly of the camshaft support structure which concerns on other embodiment of this invention. It is a figure which shows the outer ring member of the roller bearing which concerns on other embodiment of this invention. It is the figure seen from the XIII direction of FIG. It is the figure seen from the XIV direction of FIG. It is sectional drawing which looked at the state after the incorporation of the camshaft support structure of FIG. 11 from the axial direction. It is an enlarged view of the P section of FIG. It is a figure which shows the conventional camshaft support structure. It is an enlarged view of the race board and cap of the roller bearing of FIG.

Explanation of symbols

11 Internal combustion engine, 12 Cylinder block, 12a Cylinder, 13, 108 Cylinder head, 13a Intake passage, 13b Exhaust passage, 13c Bearing cap, 13d Engagement groove, 14 Piston, 15 Crankshaft, 16 Connecting rod, 17, 18 Valve, 17a , 18a Valve stem, 17b, 18b Valve head, 17c, 18c Valve spring, 19, 101 Cam shaft, 19a Shaft, 19b Cam, 19c Long diameter part, 19d Short diameter part, 101a Cam lobe, 101b Journal part, 101c Large end Diameter portion, 20 spark plug, 21, 31 needle roller bearing, 22, 32 outer ring, 22a, 22b, 32a, 32b outer ring member, 22c, 32c engaging claw, 22d, 32d flange, 22e, 24d, 32e recess, 22f, 32f flat part, 22g, 24e, 32g Convex part, 22h, 32h Oil hole, 23, 33 Needle roller, 24, 34 Cage, 24a, 24b Cut end face, 24c Pocket, 102 Roller bearing, 103 Roller, 104, 105 Holder, 106, 107 Lace board, 107a protrusion, 109 cap, 109a hollow.

Claims (4)

An outer ring formed by connecting a plurality of arc-shaped outer ring members in the circumferential direction;
A plurality of rollers disposed along the inner diameter surface of the outer ring,
The said outer ring member is a roller bearing which has an engagement piece which engages with a housing only in one side edge part among the both ends of the circumferential direction.   The roller bearing according to claim 1, wherein the engagement piece is an engagement claw obtained by bending one circumferential end of the outer ring member in the radial direction. A camshaft,
A housing that houses the camshaft;
A camshaft support structure comprising a roller bearing that rotatably supports the camshaft with respect to the housing,
The roller bearing includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in a circumferential direction, and a plurality of rollers disposed along an inner diameter surface of the outer ring, and the outer ring member has a circumferential shape. The camshaft support structure which has an engagement piece engaged with the said housing only in one side edge part among the both ends of a direction. A housing;
A cylinder provided in the housing;
A valve for opening and closing an intake passage and an exhaust passage communicating with the cylinder;
A camshaft for controlling the opening and closing timing of the valve;
An internal combustion engine comprising a roller bearing that rotatably supports the camshaft;
The roller bearing includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in a circumferential direction, and a plurality of rollers disposed along an inner diameter surface of the outer ring, and the outer ring member has a circumferential shape. An internal combustion engine having an engagement piece that engages with the housing only at one end of both ends in the direction.

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