JP2007270853A - Roller bearing for hydraulic pressure pump and method for assemblying the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roller bearing capable of having rollers of numbers equivalent to whole roller type while having non-falling off type with using a retainer, eliminating various problems of the whole roller type, having excellent assemblability and enabling to automate assembly, and suitable for use in plunger/eccentric cam contact part of a hydraulic pressure pump, and a method for assembling the same. <P>SOLUTION: This bearing includes an outer ring 1, a plurality of rollers 2 contacting a raceway surface 1a of the outer ring 1, and a ring shape retainer 3. The retainer 3 includes a plurality of pockets 4 lined in a circumference direction. A column part 5 between each pocket 4 of the retainer 3 retains the roller 2 from an inner diameter side of the rollers 2. An outer diameter d3o of a column part 5 is set to a diameter smaller than pitch circle diameter PCD of a roller arrangement. A slit having a shape cutting out the retainer from one side end to a vicinity of another side end is provided on a plurality of sections in a circumference direction of the retainer 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a bearing for a hydraulic pump used in a plunger portion of a hydraulic pump of a hydraulic pressure control device that performs anti-lock control of all wheels during braking and slip control during driving, for example, in an automobile brake device, and The present invention relates to an assembly method.

  For example, a hydraulic pump as shown in Patent Document 1 is used in the hydraulic control device of the brake device of the automobile. This type of hydraulic pump generates hydraulic pressure by moving a reciprocating plunger into and out of the pump chamber. The plunger is capable of reciprocating in the direction of the central axis, and the end surface opposite to the pump chamber is an eccentric cam. The plunger is reciprocated by rotating the eccentric cam.

  Precisely, the eccentric cam is circular so that no friction is generated between the outer peripheral surface of the eccentric cam and the end surface of the plunger when the eccentric cam rotates, and a deep groove ball bearing or needle roller bearing is formed on the outer peripheral portion of the eccentric cam. The end surface of the plunger is in contact with the outer peripheral surface of the outer ring of the bearing. Patent Document 2 is an example in which the bearing is a needle roller bearing. In Patent Document 2, the plunger is a piston.

In general, in applications where the outer diameter of the bearing is limited and a large load capacity is required, full roller bearings are often used. This is because the full roller bearing does not have a cage pillar portion between the rollers, so that the number of rollers can be increased and the load capacity can be increased as compared with a bearing with a cage.
However, full roller bearings do not have a cage, so the rollers fall off during handling before being incorporated into equipment. For this reason, various proposals have been made to keep the roller from falling off. For example, there is a configuration in which a pointed portion is provided at both ends of the roller, and the pointed portion is held by a flange of a press-made outer ring (for example, Patent Document 3). ). In addition, there is a case in which a full roller bearing is not dropped by filling with a heat solidifying grease (for example, Patent Document 4).

JP-A-8-49646 JP 2003-222226 A JP-A-6-307456 JP-A-7-238940

  FIG. 10 shows a conventional example of a plunger / eccentric cam contact portion in a hydraulic pump. In this example, a rotating shaft 23 (center O1) is supported by a pair of ball bearings 21 incorporated in the casing 20, and a circular eccentric cam 24 (center O2) is provided on the rotating shaft 23, and the eccentricity thereof. A needle roller bearing 25 is fitted on the outer periphery of the cam 24. The needle roller bearing 25 holds a plurality of needle rollers 2 incorporated in the outer ring 1 by a cage 3, and rotates the needle roller 2 on the inner diameter surface of the outer ring 1 and the outer diameter surface of the eccentric cam 24. The running surfaces 1a and 24a are caused to roll. The plunger 26 is provided so that the end surface opposite to the pump chamber is always in contact with the outer peripheral surface of the outer ring 1 of the needle roller bearing 25.

  As the rotary shaft 23 rotates, the eccentric cam 24 and the needle roller bearing 25 fitted to the outer periphery thereof rotate eccentrically, and the plunger 26 that contacts the outer peripheral surface of the outer ring 1 of the needle roller bearing 25 reciprocates. At this time, the center O2 of the eccentric cam 24 moves around the center O1 of the rotating shaft 23. For the purpose of suppressing the vibration associated therewith, balancers 27 and 28 that balance the weight around the center O1 of the rotating shaft 23 are attached to both side portions of the eccentric cam 24 on the rotating shaft 23.

  FIG. 11 shows a different conventional example. The plunger / eccentric cam contact portion in this hydraulic pump has a small diameter shaft portion 23 a at the shaft end of the rotating shaft 23, and the small diameter shaft portion 23 a is rotatably supported by a needle roller bearing 22. The other configuration is the same as that of the conventional example, and portions having the same configuration are denoted by the same reference numerals.

  10 and 11, the bearing 25 on the outer periphery of the eccentric cam receives the load from the plunger 26 on the outer diameter surface of the outer ring 1. Therefore, it is necessary to have a large outer ring strength. The outer ring strength becomes the smallest when a load is applied between the rollers 2 and 2 (the state shown in FIGS. 10 and 11B). The outer ring strength is expressed by the following calculation formula.

here,
P: Breaking load (N)
I: Outer ring cross-section secondary moment (mm ⁴ )
Z: Number of rollers σ: Fracture stress (MPa)
D, h, h2: See FIG. 12 (mm).

  The bearing shown in FIGS. 10 and 11 is a needle roller bearing with a cage. However, since a conventional needle roller bearing with a cage has a column portion 5 of the cage 3 between the rollers 2, a full roller bearing. Since the distance between the rollers 2 and 2 is wider than the outer ring strength, the outer ring strength is low. In addition, the number of rollers is small and the rated load is small compared to full roller bearings.

  On the other hand, the full roller bearing has an advantage that the rated load is larger and the outer ring strength is larger than the needle roller bearing with cage. However, in the case of a drop-off type full-roller bearing, as described above, there is a problem that the assemblability is poor because the roller falls off during handling before being incorporated into equipment.

On the other hand, the non-drop-off type full complement roller bearing has the following problems in the case of using a C end roller (for example, Patent Document 3).
-Since the roller end face is pointed, it is more expensive than the F end face or A end face roller.
-Since the roller end face is pointed, wear of the roller end face becomes noticeable in a method of use where the induced thrust force is large.
In addition, the end face shape of the roller described in the above sentence is shown in JIS B 1506, and the C end face is pointed, the F end face is flat, and the A end face is round.

Moreover, in the case of the thing (for example, patent document 4) filled with the thermosetting grease, there exist the following subjects.
・ The service temperature of the bearing is limited within the service temperature range of heat-setting grease.
・ The lubrication means of the bearing is limited (grease type and oil temperature are limited).
・ Friction is large.

  10 and 11, when the balancers 27 and 28 are provided on both sides of the eccentric cam 24, the balancers 27 and 28 can be made smaller as the mass of the bearing 25 on the outer periphery of the eccentric cam is smaller. . Therefore, in order to reduce the weight of the device, it is important to reduce the mass of the bearing 25. For this purpose, it is preferable that the outer diameter of the bearing 25 is small.

Including the above description, the following can be said about the bearings on the outer periphery of the eccentric cam of the hydraulic pump.
(1) Since a large load acts directly on the outer ring of the bearing from the plunger, the bearing on the outer periphery of the eccentric cam of the hydraulic pump requires a large outer ring strength. If insufficient, the outer ring breaks down and the function of the hydraulic pump is impaired. Needle roller bearings with cages have lower outer ring strength than full-size roller bearings of the same size.
(2) Since a large load is applied from the plunger to the bearing on the outer periphery of the eccentric cam of the hydraulic pump, the bearing requires a large rated load (load bearing performance). Insufficient indentation occurs on the rolling surface and rolling surface, and abnormal noise and vibration are generated during operation. Needle roller bearings with cages have a smaller load rating than full-size roller bearings of the same size.
(3) To reduce the size and weight of the device, it is necessary to reduce the bearing size. Needle roller bearings with cages are larger in size than full roller bearings with the same rated load.
(4) The ease of assembly of the bearing into the eccentric cam must also be considered. The drop-off type full-roller bearing is not easily assembled because the roller falls off.
(5) The non-drop-off type full-roller bearing using C end face rollers is more expensive than the F end face or A end face rollers because the end face of the roller is pointed. Since the end face of the roller is pointed, wear of the end face of the roller becomes noticeable in a method of use where the induced thrust force is large. The effective length of the roller is shortened by the dimension of the pointed portion.
(6) Non-drop-off type full complement roller bearings filled with thermosetting grease have a limited operating temperature within the operating temperature range of thermosetting grease. In addition, the lubrication means of the bearing is limited (the type of grease and the type of oil are limited). Furthermore, the friction is large. If the friction of the bearing on the outer periphery of the eccentric cam is large, the required capacity of the power source (motor or hydraulic pressure) also increases.
(7) A sliding bearing (resin-coated product) is loose when the coating film is peeled off or worn.
(8) Sliding bearings (with or without coating) have higher friction than rolling bearings. If the friction of the bearing on the outer periphery of the eccentric cam is large, the required capacity of the power source (motor or hydraulic pressure) also increases.
(9) In the case of a shell-type needle roller bearing with cage, in order to perform edge bending by incorporating the roller and cage after heat treatment of the outer ring, there is a step of annealing the post-bending wrinkles, or a step of carburization and removal As a result, the number of assembly processes is large and the assembly cost is high.

  The object of the present invention is to make it possible to have the same number of rollers as the full-roller type while using the retainer to make it a non-drop-off type, and to solve various problems of the full-roller type. It is an object of the present invention to provide a roller bearing suitable for use in a plunger / eccentric cam contact portion of a hydraulic pump and an assembling method thereof.

  A roller bearing for a hydraulic pump according to a first aspect of the present invention includes an outer ring, a plurality of rollers in contact with a rolling surface of the outer ring, and a ring-shaped cage, wherein the cage is the roller. In a roller bearing having a ladder shape in which a plurality of pockets for holding the rollers are arranged in the circumferential direction, a column portion between each pocket holds the roller from the inner diameter side between the rollers, and the column of the cage The outer diameter of the part is smaller than the pitch circle diameter of the roller arrangement, and is formed in a plurality of locations in the circumferential direction of the retainer, notched from one edge of the retainer to the vicinity of the other edge. A slit is provided, and is used between the eccentric cam and the plunger in a hydraulic pump that generates hydraulic pressure by reciprocating the plunger with the eccentric cam and moving the plunger into and out of the pump chamber. On the outer peripheral surface of the eccentric cam Contact, characterized in that it is intended to abut against an end portion of the plunger to the outer ring.

According to this configuration, the retainer column portion holds the roller from the inner diameter side between the rollers, and the outer diameter of the column portion is smaller than the pitch circle diameter of the roller arrangement. It can be assumed that it does not exist on the pitch circle of the roller arrangement. Therefore, the interval between the rollers is not widened by the column portion, and the number of rollers can be approximately the same as the total roller type while using a cage to make the roller non-dropping type. For this reason, for example, the following advantages are obtained.
(1) Since the same number of rollers as a full roller bearing can be maintained, the distance between the rollers is small, so that sufficient outer ring strength can be obtained even if the outer ring plate thickness is thin. Therefore, the outer ring can be made thinner than the needle roller bearing with cage.
(2) Since the same number of rollers as a full roller bearing can be maintained, the load capacity increases, and a sufficient load rating can be obtained even with a small bearing size. For this reason, compared with deep groove ball bearings, angular contact ball bearings, and needle roller bearings with a cage of the same size, the rated load is large, and the load bearing performance can be improved, the size can be reduced, and the life can be extended. Since the load-bearing performance is good, it is possible to prevent the generation of noise and vibration feeling during operation, for example, by generating indentations on the rolling surface and the rolling surface.
(3) Along with the reduction in weight of the bearing part, it is possible to design a lightweight and compact design for peripheral parts such as balancers.
(4) Since the built-in roller can be held without dropping, the assemblability improves compared to the drop-off type full roller bearing.
(5) With the cage of the present invention, since the rollers can be removed, there is no need to use C-end rollers, and F-end surfaces and A-end rollers (rollers with a long effective contact length) can be used. For this reason, a width dimension can be made small. Also, the cost is low.
(6) Since the roller can be made to fall off by the cage of the present invention, it is not necessary to make the roller not fall off by the thermosetting grease. For this reason, lubrication can be freely selected, the operating temperature range is widened, and the friction is low. Since the friction is low, the required capacity of the power source (motor or hydraulic pressure) can be reduced.
(7) The coating film is not peeled off or worn out as in the case of the sliding bearing (resin coated product), and the backlash due to wear or the like does not occur.
(8) Low friction compared to plain bearings (with or without coating). For this reason, the required capacity of the power source (motor and hydraulic pressure) can be reduced.
(9) By adopting the present invention (provided with slits), it becomes possible to perform heat treatment after edge bending of the bend on the back-bending side and then incorporate the cage, so that the conventional cage The number of processes is reduced and the cost is reduced as compared with assembly of a shell-type needle roller bearing with a flange. In addition, since the outer ring hardness on the rear bending side can be ensured, the service life is extended.

  In assembling the bearing, after the rollers are arranged on the inner periphery of the outer ring, the cage can be inserted from the opening end side of the slit into the roller array while reducing the diameter of the cage. Thereafter, the cage is naturally restored to its original diameter by the elasticity of the material, so that each roller enters the pocket and the bearing is assembled. In the insertion of the cage, since the cage has a slit, the cage can be deformed within the elastic region of the material. Therefore, the cage is less deformed by deformation and can prevent deterioration in accuracy due to deformation. As a result, it is possible to improve assemblability and accuracy, and to automate assembly.

In this invention, the slit may also serve as a pocket for holding rollers. In other words, a removal portion may be provided at the pocket in the ring-shaped portion at the side end of the cage, and the slit may be configured by the removal portion and the pocket.
By disposing the rollers in the slit, the number of rollers can be increased while providing the slit, and the load capacity of the roller bearing can be increased.

In this invention, the outer diameter dimension of the ring-shaped body assumed to have joined the arc-shaped circumferential direction portions excluding the slit of the cage is smaller than the inscribed circle diameter of the roller arrangement. The circumferential width of the slit and the number of slits may be set.
By setting in this way, after the rollers are arranged on the inner circumference of the outer ring, the work of inserting the cage from the opening end side of the slit to the inside of the roller array while reducing the diameter of the insertion side portion of the cage is performed. This can be done and the assembly is further improved.

In this invention, it is good also considering the edge part of the outer diameter surface of the said holder | retainer as the tapering shape or the taper shape of a cross-sectional arc shape.
By configuring in a tapered shape, the cage can be more smoothly inserted into the inner side of the roller array at the time of assembly, and the assemblability is further improved.

A roller bearing for a hydraulic pump according to a second aspect of the present invention includes an outer ring, a plurality of rollers in contact with a rolling surface of the outer ring, and a ring-shaped cage, wherein the cage is the roller. In a roller bearing having a ladder shape in which a plurality of pockets for holding the cage are arranged in the circumferential direction, the cage is cut at a plurality of locations in the circumferential direction from one side edge of the cage to the vicinity of the other side edge. Used in a hydraulic pump between the eccentric cam and plunger in a hydraulic pump that is provided with a slit with a missing shape and generates hydraulic pressure by reciprocating the plunger with the eccentric cam and moving the plunger into and out of the pump chamber. The rollers are in rolling contact with the outer peripheral surface of the eccentric cam, and the end of the plunger is brought into contact with the outer ring.
In the case of this configuration, the effect of having the same number of rollers as the full roller type is not necessarily obtained, but the assembling property of the bearing by inserting the cage can be obtained as well as the first invention. That is, after the rollers are arranged on the inner circumference of the outer ring, the cage is inserted from the opening side end of the slit to the inside of the roller array while reducing the diameter of the insertion side portion of the cage, and then the cage is made of the material. Roller bearings can be assembled by returning to the original diameter with the elasticity they have. At this time, since the slit is provided for insertion of the cage, the cage can be deformed within the elastic region of the material, the cage is less bent and deformed, and accuracy deterioration due to deformation is prevented. It is possible to improve the assemblability and the accuracy.

A first method for assembling a roller bearing for a hydraulic pump according to the present invention is a method for assembling a roller bearing in which the cage has the slit only on one side in the roller bearing for a hydraulic pump according to any one of the configurations of the present invention. It is. In this assembling method, after the rollers are arranged on the inner periphery of the outer ring, the retainer is inserted axially into the inner side of the roller array, and this insertion work is performed by an expandable / contractible chuck whose inner surface is a conical surface. It is performed by pushing in with a pushing jig while reducing the diameter of the insertion side portion of the cage, and after this insertion, the cage is restored to its original diameter by the elasticity of the material.
According to this method, the retainer has a slit on only one side because it is pushed in by the pushing jig while the diameter of the insertion side portion of the cage is reduced by the expandable / contractable chuck whose inner diameter surface is a conical surface. However, the cage can be easily inserted in the roller array in the axial direction. In addition, an excessive load is not applied to the cage at the time of insertion, so that a decrease in accuracy due to deformation at the time of insertion is prevented, and an improvement in assembly and accuracy can be obtained. Also, assembly can be automated.

A second method for assembling a roller bearing for a hydraulic pump according to the present invention is a method for assembling a roller bearing in which the cage has the slits on both sides in the roller bearing for a hydraulic pump according to any one of the configurations of the present invention. is there. In this assembling method, after the rollers are arranged on the inner circumference of the outer ring, the retainer is inserted axially into the inner side of the roller array, and this insertion operation is pushed into a guide jig whose inner surface is a conical surface. This is performed while reducing the diameter of the cage, and after this insertion, the cage is restored to its original diameter by the elasticity of the material.
In the case of this method, the roller bearing can be assembled only by pushing the cage into the guide jig described above without using a jig such as a collet chuck. In this case, there is little bending deformation of the cage, it is possible to prevent a decrease in accuracy due to the deformation, and it is possible to improve assemblability and accuracy. Further, since the cage has slits on both sides, the directionality in the way of assembling the cage can be eliminated, and the assemblability is further improved. Furthermore, the assembly can be automated with a simple device.

  The hydraulic pump roller bearing of the present invention has an outer ring, a plurality of rollers in contact with the rolling surface of the outer ring, and a ring-shaped cage, and the cage circumferentially defines a pocket for holding the roller. In a roller bearing which is a ladder-like one provided in a plurality in the direction, a column portion between each pocket holds the roller from the inner diameter side between the rollers, and the outer diameter of the column portion of the cage is a roller. An eccentric cam having a smaller diameter than the pitch circle diameter of the array and having a shape cut out from one side edge of the cage to the vicinity of the other side edge at a plurality of locations in the circumferential direction of the cage. In a hydraulic pump that generates hydraulic pressure by reciprocating the plunger and moving the plunger into and out of the pump chamber, the roller is used between the eccentric cam and the plunger, and the rollers roll on the outer peripheral surface of the eccentric cam. In contact with the outer ring. Since the end of the jar is brought into contact, it is possible to have the same number of rollers as the full-roller type while using the retainer to make it a non-drop-off type, eliminating various problems with the full-roller type. be able to. Moreover, it is excellent in assemblability and can be automated. This makes it suitable for use in the plunger / eccentric cam contact portion of the hydraulic pump.

  A first embodiment of the present invention will be described with reference to FIGS. This roller bearing for a hydraulic pump is used for the plunger / eccentric cam contact portion of the hydraulic pump shown in FIG. 1 or FIG. The plunger / eccentric cam contact portion of FIG. 1 is obtained by applying the roller bearing for a hydraulic pump of the present invention to the plunger / eccentric cam contact portion of FIG. The plunger / eccentric cam contact portion of FIG. 2 is obtained by applying the hydraulic pump roller bearing of the present invention to the plunger / eccentric cam contact portion of FIG. Since the basic configuration of the plunger / eccentric cam contact portion in FIGS. 1 and 2 is the same as that shown in FIGS. 10 and 11, the same components are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 3, the roller bearing 25 of this embodiment includes an outer ring 1, a plurality of rollers 2 in contact with a rolling surface 1 a formed by an inner diameter surface of the outer ring 1, and a ring-shaped cage 3. The cage 3 is a ladder having a plurality of pockets 4 arranged in the circumferential direction, and a column portion 5 between the pockets 4 is located between the rollers 2 to hold the rollers 2 from the inner diameter side. .

  The outer ring 1 has flanges 1b on both sides. The outer ring 1 is a shell type, that is, a press-formed product of a steel plate. The roller 2 is made of steel such as bearing steel.

  The cage 3 is made of an elastically deformable synthetic resin such as polyamide (for example, PA66, PA46) or polyacetal. The cage 3 uses these synthetic resins in a non-reinforced state or a state in which a reinforcing fiber such as carbon fiber or glass fiber is added in an amount of 30% or less. It has been given moderate strength and flexibility.

  As shown in FIGS. 4A to 4C, the cage 3 has both ends in the width direction as ring-shaped portions 6, and the column portions 5 are circular between the ring-shaped portions 6 on both sides. A plurality are provided in the circumferential direction. A space between the pillar portions 5 becomes a pocket 4 in which the roller 2 is inserted.

  As shown in FIG. 3B, the cross-sectional shape of the pillar portion of the cage 3 is substantially triangular. The inner diameter d3i of the cage 3 is set to be 0.1 mm or more larger than the maximum diameter d2i of the inscribed circle diameter of the roller arrangement. The 0.1 mm dimension is preferably equal to or greater than this value regardless of the bearing size. The outer diameter dimension d3o of the arrangement of the column portions 5 of the cage 3 is made smaller than the pitch circle diameter PCD of the roller arrangement. For example, it is smaller than the pitch circle diameter PCD by 0.1 mm or more. The dimension to be smaller than the pitch circle diameter PCD may be a predetermined ratio or more designed according to the bearing dimensions and the like. The thickness B of the column portion 5 of the cage 3 is preferably 15 to 30% of the roller diameter Dw.

As shown in each example of FIGS. 4 (A) to (C), the cage 3 was cut out at a plurality of locations in the circumferential direction from one side edge of the cage 3 to the vicinity of the other side edge. The slits 7 and 7A having a shape are provided.
FIG. 4A shows an example of the cage 3 in which the slit 7 is only cut out from one side edge (left side in the drawing).
In FIG. 4B, there are slits 7 cut out from one side edge and slits 7 cut out from the other side edge so that the slits 7 on both sides are arranged in a staggered pattern in the circumferential direction. The example of the holder | retainer 3 provided in is shown.
4A and 4B, the retainer 3 in each of the examples shown in FIGS. 4A and 4B is a pocket between the adjacent column portions 5 and a portion of the ring-shaped portion 6 from which substantially the entire portion between the adjacent column portions 5 is removed. The slit 7 is constituted by a portion that also serves as a part.

  FIG. 4C is an example of a slit cutout shape. The notch shape may leave the ring-shaped part 6 like the slit 7A. In the case of the slit 7 which does not leave the ring-shaped portion, the corner portion may be R or a taper. Thereby, the width | variety surface of the holder | retainer 3 can be made difficult to catch on other members, such as a side plate.

4A and 4B, the pockets 4 and the slits 7 are alternately formed in each example, and the column portion 5 is interposed between the pocket 4 and the slit 7 that also serves as a pocket. It is supposed to be provided.
The pockets 4 and the slits 7 are not alternate, and the slits 7 may be provided by opening a plurality of pockets 4 in an array.
The cross-sectional shape of the column portion 5 is the shape described above with reference to FIG. 3B both for the space between the pocket 4 and the slit 7 and between the adjacent dedicated pockets 4.

  FIG. 5 is an explanatory view showing the one side edge side where the slit 7 (7 </ b> A) of the cage 3 is cut out before the diameter reduction deformation and after the diameter reduction deformation. As shown in the figure, the retainer 3 has an outer diameter d16o of a ring-shaped body 16 that is assumed to be connected to arcuate circumferential portions (ring-shaped portions 6) excluding the slits 7 (7A). The circumferential width W and the number of slits of the slit 7 (7A) of the cage 3 are set so as to be smaller than the inscribed circle diameter d2i. When the pockets 4 and the slits 7 are alternately provided as in the examples of FIGS. 4A and 4B, the dimensional relationship between the outer diameter d16o and the inscribed circle diameter d2i is naturally satisfied. It is preferable to satisfy the dimensional relationship between the outer diameter d16o and the inscribed circle diameter d2i even in the example of FIG. 4C or when the number of other slits 7 formed is small or the opening width is small.

According to the roller bearing 25 having the above-described configuration, the column portion 5 of the cage 3 holds the roller 2 from the inner diameter side, and the shape of the column portion is substantially triangular. Therefore, the cage column portion 5 has a pitch circle diameter of the roller arrangement. It may not be present on the PCD. Therefore, the arrangement interval of the rollers 2 is not widened by the column portion 5, and the number of rollers can be the same as the total roller type, or the number of rollers can be reduced by one or two. For example, the number of rollers is increased by 10 to 50% compared to a conventional roller bearing. Further, the strength of the column portion 5 is ensured.
Further, since the inner diameter d3i of the cage 3 is set to be 0.1 mm or more larger than the maximum diameter of the inner diameter circle diameter d2i of the roller arrangement, a gap of 0.1 mm or more is generated between the eccentric cam 24 and the cage 3. For this reason, the cage 3 does not come into strong contact with the eccentric cam 24, and an increase in the friction torque by the cage 3 is avoided.
Further, the outer diameter dimension d3o of the arrangement of the column parts 5 of the cage 3 is made smaller than the pitch circle diameter PCD of the roller arrangement, and the degree of the reduction is, for example, 0.1 mm or more smaller than the pitch circle diameter PCD. Therefore, it is not necessary to widen the interval between the roller arrangements, and it is avoided that the outermost diameter portion in the cross section of the column portion 5 becomes too thin and the strength becomes insufficient.
From these facts, various problems of the full-roll type can be solved.

By providing the retainer 3 with the slit 7 (7A) as described above, for example, assembling methods as shown in FIG. 6 or FIG. 7 can be employed.
The first assembling method shown in FIG. 6 is a method of assembling a roller bearing in which the cage 3 has slits 7 (7A) only on one side, for example, a roller bearing 25 having the cage 3 shown in FIG. 4 (A). In this method, after the rollers 2 are arranged on the inner periphery of the outer ring 1, the cage 3 is inserted in the axial direction from the opening end side of the slit 7 (7A) to the inside of the roller array. The roller 2 is arranged on the inner periphery of the outer ring 1 by, for example, applying grease to the roller 2 and attaching the roller 2 to the outer ring 1 due to the adhesiveness of the grease. In this case, the cage insertion operation is performed by pushing in the pushing jig 12 while the diameter of the insertion side portion of the cage 3 is reduced by the expandable / shrinkable chuck 11 whose inner diameter surface is a conical surface. As the chuck 1, a chuck made up of a plurality of divided chucks arranged in the circumferential direction can be used. There is a collet chuck or the like as this type of chuck. After the insertion of the cage 3, the cage 3 is naturally restored to its original diameter by the elasticity of the material. Thereby, each roller 2 is inserted into the pocket 4 of the cage 3.

  By assembling the roller bearing 25 in this way. Since the cage 3 can be deformed within the elastic region of the material, the cage 3 is less bent and deformed, accuracy deterioration associated with the deformation can be prevented, and assemblability and accuracy can be improved. Also, assembly can be automated.

  The second assembling method shown in FIG. 7 is a method of assembling a bearing having slits 7 on both sides of the cage 3, for example, a roller bearing having the cage 3 shown in FIG. Also in this method, after the rollers 2 are arranged on the inner periphery of the outer ring 1, the cage 3 is inserted into the roller array in the axial direction. In this case, the insertion work is a guide in which the inner diameter surface is a conical surface. This is performed by reducing the diameter of the insertion side portion of the cage 3 by pushing it into the jig 13. After this insertion, the cage 3 is naturally restored to its original diameter by the elasticity of the material. Thereby, each roller 2 is inserted into the pocket 4 of the cage 3.

  As described above, when the cage 3 having the zigzag slits 7 on both sides is used, the roller bearing is assembled by simply pushing the cage 3 into the guide jig 13 without using chucks. Can do. Also in that case, there is little bending deformation of the holder | retainer 3, it can prevent the precision fall accompanying a deformation | transformation, and can aim at the improvement of assembly property and precision improvement. Further, since the slits 7 are provided on both sides of the cage 3, the assembling direction of the cage 3 can be eliminated, and the assemblability is further improved. Further, the assembly can be automated with a simple configuration.

  FIG. 8 shows a state in which the roller 2 is inserted into the pocket 4 of the cage 3 in the assembled state. FIG. 8A shows the case where the cage 3 having the slit 7 on only one side (example of FIG. 4A) is used. Here, the roller 2 is disposed not only in the pocket 4 but also in the slit 7. ing. Thereby, the load capacity of the roller bearing can be increased. FIG. 8B shows a case where the cage 3 having the slits 7 on both sides (example of FIG. 4B) is used. In this case, the roller 2 is arranged not only in the pocket 4 but also in the slit 7. The

  According to the roller bearing 25 having this configuration, the slits 7 and 7A having a shape cut out from one side edge of the cage 3 to the vicinity of the other side edge are provided at a plurality of locations in the circumferential direction of the cage 3. It can be inserted while reducing the diameter of the insertion side portion of the cage 3. Therefore, the cage 3 can be deformed within the elastic region of the material, the cage 3 is less bent and deformed, accuracy can be prevented from being lowered due to the deformation, and assemblability and accuracy can be improved. Further, the pillars 5 between the pockets 4 in the cage 3 and between the pockets 4 and the slits 7 and 7A hold the rollers 2 from the inner diameter side between the rollers 2, and the outer diameter d3o in the pillar 5 of the cage 3 is set. Since the diameter is smaller than the pitch circle diameter PCD of the roller arrangement, the retainer 3 can prevent the rollers 2 from falling off.

  In the above-described embodiment, the outer ring 1 may be SCM material carburizing and quenching, SPC material carburizing and quenching, or other equivalent materials and heat treatment. In this case, even after the both sides of the outer ring 1 are bent to form the flange 1b, the cage 3 can be incorporated, and there is no need to reduce the strength of the outer ring flange 1b. That is, when the outer ring 1 is not used as the treatment material, the roller 2 and the cage 3 are assembled after the one side of the outer ring 1 is bent, and the other side of the outer ring 1 is bent at the both ends 1b, 1b. Will be formed. In this case, since the last edge bending of the outer ring 1 is performed after the outer ring 1 is heat-treated, the edge bending is performed after the edge bending scheduled portion is annealed, and the strength of the outer ring flange portion 1b is reduced. Such a decrease in strength can be avoided by adopting a configuration in which the cage 3 can be incorporated after edge bending.

  In the above embodiment, the case where the outer ring 1 is a press-molded product has been described as an example. However, the present invention is not limited thereto, and the cage 3 having the above-described configuration is incorporated even when the outer ring 1 is made of a machined product. As a result, the assemblability can be improved and the accuracy can be improved.

Moreover, as shown in FIG. 9, it is preferable that the edge 3a of the outer diameter surface 3 of the cage 3 has a tapered shape or a tapered shape with a circular arc shape.
FIG. 9A shows an example in which the left and right edges 3a of the outer diameter surface of the cage 3 are tapered and tapered, and the cage 3 has slits 7 on both sides (FIG. 4B). Example) is used. Thus, by making the edge portion 3a of the outer diameter surface of the cage 3 into a tapered tapered shape, the cage 3 can be smoothly inserted into the inner side of the above-described roller array during assembly. As a result, the assemblability is further improved. Here, in the cage 3 having the slits 7 on both sides regardless of the direction of assembling, both edges 3a of the outer diameter surface are tapered and tapered, so that the cage 3 is arranged from either side edge. Even if it is inserted into the inside, the insertion can be performed smoothly. In the example of FIG. 9A, the outer ring 1 is a machined product.

  FIG. 9B shows an example in which one edge 3a of the outer diameter surface of the cage 3 is a tapered shape with a circular arc cross section. The cage 3 uses a type having a slit 7 (7A) on one side, for example, the example shown in FIG. In this case, the edge portion 3a having a tapered shape is the edge portion 3a on the side where the slit 7 (7A) is notched, and the retainer 3 is a roller from the opening end side of the slit 7 (7A) during the above-described assembly. Inserted inside the array. Thereby, insertion of the holder | retainer 3 can be performed smoothly and assembly property improves further. In the example of FIG. 9B, the outer ring 1 is a press-formed product.

Further, in each of the above embodiments, the cage 3 holds the roller 2 from the inner diameter side between the rollers 5 and the column portions 5 between the pockets 4, and the outer diameter d <b> 3 o of the row of the column portions 5 of the cage 3. However, although the diameter is smaller than the pitch circle diameter PCD of the roller arrangement, the above-described slits 7 and 7A may be provided in the cage 3 that does not have such a condition.
In that case, the effect of having the same number of rollers as the full roller type is not necessarily obtained, but the assembling property of the bearing by inserting the cage can be obtained satisfactorily as in the above embodiment. That is, after the rollers are arranged on the inner circumference of the outer ring, the cage is inserted from the opening side end of the slit to the inside of the roller array while reducing the diameter of the insertion side portion of the cage, and then the cage is made of the material. Roller bearings can be assembled by returning to the original diameter with the elasticity they have. At this time, since the slit is provided for insertion of the cage, the cage can be deformed within the elastic region of the material, the cage is less bent and deformed, and accuracy deterioration due to deformation is prevented. It is possible to improve the assemblability and the accuracy.

(A) is sectional drawing of an example of the plunger and eccentric cam contact part of the hydraulic pump provided with the roller bearing for hydraulic pumps concerning embodiment of this invention, (B) is the IB-IB sectional drawing. (A) is sectional drawing of the example from which the plunger and eccentric cam contact part of a hydraulic pump provided with the roller bearing for hydraulic pumps differs, (B) is the IIB-IIB sectional drawing. (A) is a partial longitudinal cross-sectional view of the roller bearing for the hydraulic pump, and (B) is a partial cross-sectional view thereof. (A) is a partial front view showing an example of the cage of the roller bearing, (B) is a partial front view showing another example of the cage, and (C) is a partial front view showing still another example of the cage. It is. It is explanatory drawing which compares and shows the diameter reduction before and after diameter reduction change of the holder | retainer. It is explanatory drawing of the 1st assembly method of the roller bearing. It is explanatory drawing of the 2nd assembly method of the roller bearing. (A) is a partial front view which shows an example of the arrangement state of the roller to a holder | retainer, (B) is a partial front view which shows the other example of the arrangement state of a roller. (A) is a fragmentary sectional view of other embodiment in this invention, (B) is a fragmentary sectional view of further another embodiment. (A) is sectional drawing of an example of the plunger and eccentric cam contact part of the hydraulic pump provided with the conventional roller bearing for hydraulic pumps, (B) is the XB-XB sectional drawing. (A) is sectional drawing of the example from which the plunger and eccentric cam contact part of a hydraulic pump provided with the roller bearing for hydraulic pumps differs, (B) is the XIB-XIB sectional drawing. It is explanatory drawing which shows the dimension of an outer ring | wheel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer ring 1a, 24a ... Rolling surface 2 ... Roller 3 ... Cage 4 ... Pocket 5 ... Column part 7, 7A ... Slit 20 ... Casing 21 ... Ball bearing 22 ... Needle roller bearing 23 for rotating shaft support ... Rotating shaft 24 ... Eccentric cam 25 ... Needle roller bearing 26 on the outer periphery of the eccentric cam ... Plunger 27, 28 ... Balancer Dw ... Roller diameter PCD ... Pitch circle diameter d2i of roller arrangement ... Maximum diameter d3i of inscribed circle diameter of roller arrangement ... Cage Inner diameter dimension d3o ... outer diameter dimension of the column

Claims (7)

A ladder-like one having an outer ring, a plurality of rollers in contact with the rolling surface of the outer ring, and a ring-shaped cage, wherein the cage is provided with a plurality of pockets for holding the rollers arranged in the circumferential direction. In the roller bearing
Columns between the pockets hold the rollers from the inner diameter side between the rollers, and the outer diameter of the column of the cage is smaller than the pitch circle diameter of the roller arrangement, and the cage circle In a plurality of locations in the circumferential direction, slits of a shape cut out from one side edge of this cage to the vicinity of the other side edge are provided,
In a hydraulic pump that generates hydraulic pressure by reciprocating the plunger with an eccentric cam and moving the plunger into and out of the pump chamber, the rollers are used between the eccentric cam and the plunger, and each roller is an outer peripheral surface of the eccentric cam. A roller bearing for a hydraulic pump, wherein the end of the plunger is brought into contact with the outer ring.   The roller bearing for a hydraulic pump according to claim 1, wherein the slit also serves as a pocket for holding the roller.   In Claim 1 or Claim 2, the outer diameter dimension of the ring-shaped body assumed that the circular-arc-shaped circumferential direction part except the said slit of the said holder | retainer was joined so that it might become smaller than the inscribed circle diameter of a roller arrangement | sequence. A roller bearing for a hydraulic pump in which the circumferential width of the slit of the cage and the number of slits are set.   The roller bearing for a hydraulic pump according to any one of claims 1 to 3, wherein an edge of an outer diameter surface of the cage is a tapered shape having a taper shape or a circular arc shape in cross section. A ladder-like one having an outer ring, a plurality of rollers in contact with the rolling surface of the outer ring, and a ring-shaped cage, wherein the cage is provided with a plurality of pockets for holding the rollers arranged in the circumferential direction. In the roller bearing
At a plurality of locations in the circumferential direction of the cage, slits in a shape cut out from one side edge of the cage to the vicinity of the other side edge are provided,
In a hydraulic pump that generates hydraulic pressure by reciprocating the plunger with an eccentric cam and moving the plunger into and out of the pump chamber, the rollers are used between the eccentric cam and the plunger, and each roller is an outer peripheral surface of the eccentric cam. A roller bearing for a hydraulic pump, wherein the end of the plunger is brought into contact with the outer ring. A method for assembling a roller bearing for a hydraulic pump, wherein the retainer has the slit only on one side of the roller bearing for the hydraulic pump according to any one of claims 1 to 5. ,
After the rollers are arranged on the inner circumference of the outer ring, the cage is inserted axially into the inner side of the roller array, and this insertion work is performed on the insertion side of the cage by an expandable / contractible chuck whose inner diameter surface is a conical surface. A method for assembling a roller bearing for a hydraulic pump, wherein the roller bearing is reduced in diameter while being pushed by a pushing jig, and after this insertion, the cage is restored to its original diameter by the elasticity of the material. Among the roller bearings for a hydraulic pump according to any one of claims 1 to 5, a method for assembling a roller bearing for a hydraulic pump in which the cage has the slits on both sides,
After the rollers are arranged on the inner circumference of the outer ring, the cage is inserted in the axial direction into the inner side of the roller array, and this insertion work is performed by pushing the cage into the guide jig whose inner surface is a conical surface. A method for assembling a roller bearing for a hydraulic pump, wherein the assembly is performed while the diameter is reduced, and the cage is restored to its original diameter by the elasticity of the material after the insertion.

Images