JPH03228566A - Support structure of shaftless roller - Google Patents

Abstract

PURPOSE:To prevent the movement of a shaftless roller in the thrust direction, by providing a backup roller which abuts on the position where the abutting pressure of the rotating or moving member of a shaftless roller peripheral face is received with good balance, and more than a pair of conical rollers which abut on the roller peripheral face in the state of the mutual small diameter side and large diameter side being reversed. CONSTITUTION:A shaftless roller 18 is interposed rotatably from three directions with the three rollers of a backup roller 19 abutted on the position where the abutment pressure of the rotating or moving member of the shaftless roller 18 is received with good balance and a pair of conical rollers 20 arranged so that the mutual small diameter side and large diameter side are abutted reversely on the roller peripheral face at the position apart by the angle of less than 90 deg. from the abutment position of the rotating or moving member. The movement in the thrust direction is limited by the tangential force generated as the force toward the large diameter side of each conical roller, in the case of a pair of the conical rollers 20 whose large diameter side and small diameter side are reversely abutted mutually on the other peripheral face of the cylindrical shaftless roller 18 being rotated respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a structure for rotatably supporting a shaftless roller having no rotating shaft.

2. Description of the Related Art As a method of supporting a rotationally driven shaftless roller by bringing the peripheral surface of the roller into contact with a rotating member or a relatively moving member, a method using a sliding bearing as shown in FIG. 5 is known. This involves fitting the shaftless roller 1 into a supporting member 2 having a recess 2a with a fittable arcuate cross section with a predetermined gap around the support member 2, and connecting the outer periphery of the shaftless roller 1 and the inside of the recess 2a. It is used by forming an oil film between it and the periphery to lubricate it. However, with this support method using the support member 2, the shaftless roller 1
It is possible to receive the load in the radial direction applied to the shaft, but it is not possible to receive the load in the thrust direction.Therefore, it is necessary to provide additional members to receive the thrust load on both sides of the shaftless roller 1. The width of the shaftless roller 1 is considerably wider than that of the shaftless roller 1.

In addition, when the shaftless roller 1 is fitted into the recess 2a of the support member 2 and supported in this way, if a large load is applied in the radial direction, the lubrication performance decreases and smooth rotation is inhibited. At the same time, there is a problem that heat generation increases. Therefore, in such a case, a method is adopted in which one or more backup rollers are brought into contact with the peripheral surface of the shaftless roller 1 to rotatably support it.

For example, Figure 6 shows the conventional arrangement of rollers when performing roller burnishing, which is one of the surface finishing methods for metal parts. A cylindrical workpiece W is held between three shafted rollers: a pair of vanish rollers 4.4 held therein, and a vanish roller 6 rotatably held by a roller holder 5 on the movable side. By pressing the burnish roller 6 toward the center of the workpiece W with a large force via the roller holder 5, the three burnish rollers 4, 4.5 pinch the outer peripheral surface of the workpiece W, giving plastic deformation to the machined surface. It is used to finish the surface smoothly and to improve the hardness of the surface. For example, it is used as a finishing process for the surface of the pin part 7a that attaches the connecting rod of the crankshaft 7, which is a workpiece, or the journal part 7b that is bearing on the cylinder block side. (See Figure 7).

However, in this case, as shown in FIG. 7, in order to finish the entire width of the pin portion 7a or journal portion 7b of the crankshaft 7, a burnish roller with approximately the same width as the pin portion 7a or journal portion 7b is used. However, if burnish rollers of approximately the same width are used, the kg between each burnish roller 4, 4.6 and the crank arm 7C or balance weight 7d will be narrower, and the distance between the crank arms 7c will be smaller. Alternatively, it is difficult to support each burnish roller 4, 4.degree. 6 between the balance weights 7d by the rotating shaft. Therefore, we made the vanish roller large in diameter, and the balance weight 7 has a narrow rotation axis.
It can also be installed outside of the distance between d,
Increasing the diameter of the burnish roller has the disadvantage that the machining surface pressure decreases. Therefore, when providing a burnish roller in such a portion, it is conceivable to use a shaftless roller as the burnish roller.

In such a case, as shown in FIG. 8, a cylindrical backup roller 9 is placed at a position opposite to the abutment position of the pin portion 7a of the crankshaft and the center of the shaftless banyroll roller 8, and its rotation is By arranging the shaft 9a supported by the roller holder 10 and using a backup roller 9 with a large diameter, the distance from the rotating shaft 9a to the workpiece contact position of the vanish roller 8 can be reduced! is made longer so that the rotating shaft 9a is positioned outside the narrow space between the crank arms 7c or between the balance weights 7d and not interfering with each other. Therefore, by using the burnish roller 8 as an axisless roller, its opening width can be made the same width as the processed surface of the pin portion 7a.

Problems to be Solved by the Invention However, as described above, in the conventional support structure in which the cylindrical backup roller 9 supports the load received by the shaftless vanish roller 8, although the load in the radial direction can be supported, the thrust Since the vanish roller 8 cannot support the load in the thrust direction, it is necessary to accommodate the shaftless vanish roller 8 in the roller holder 10 to restrict movement in the thrust direction. Furthermore, in the above-mentioned support structure, there was a problem in that the bunnage roller 8 would fall off from the roller holder 10 when the contact with the crankshaft 7 was released.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a support structure for an axisless roller that restricts movement in the thrust direction.

Means for Solving the Problems As a means for solving the above problems, the present invention provides a support structure for a shaftless roller that is rotationally driven by contacting a rotating or relatively moving member, wherein the shaftless roller comprises:
A backup roller is arranged so as to be in contact with the roller circumferential surface at a position that receives the contact pressure of the rotating or moving member in a well-balanced manner, and the It is characterized in that it is supported by one or more pairs of conical rollers or clutch-shaped rollers that are arranged so as to come into contact with the peripheral surface of the rollers.

Action: The axisless roller is brought into contact with the backup roller in a position that receives the contact pressure of the rotating or moving member in a well-balanced manner, and the back-up roller is placed in a position that is less than 90 degrees away from the contact position of the rotating or moving member. It is rotatably held in three directions by three rollers, including a pair of conical rollers, which are disposed so that the small diameter side and the large diameter side are in contact with the circumferential surface of the roller in opposite directions. When a pair of conical rollers, the large diameter side and the small diameter side of which are in contact with the outer peripheral surface of a cylindrical shaftless roller in opposite directions, respectively rotate, a force is generated toward the large diameter side of each conical roller. The movement in the thrust direction is limited by the tangential force.

EXAMPLE Hereinafter, a first example will be described in which the shaftless roller support structure of the present invention is applied to the shaftless burnish roller support structure of a roller burnishing machine that performs burnishing on the pin portion and journal portion of the crankshaft. This will be explained based on the drawings to FIG.

As shown in FIG. 3, the roller burnishing machine 11 is
A frame 12 is formed by punching out a flat plate into an approximately U-shape, and the U-shaped frame 12 is detachable so as to close the open end (the left end in FIG. 3) when the two sides of the U-shaped frame 12 are arranged at the top and bottom. A roller holder 13 is provided in the frame 12 and has a V-shaped notch in the center and is formed to have approximately the same thickness as the frame 12, and guide rollers 14 are respectively attached to two parallel upper and lower sides of the U-shaped frame 12. A trolley 15 is provided so as to be movable in the horizontal direction between both sides in contact with each other, and is formed to have approximately the same thickness as the frame 12. A hydraulic cylinder 16 that drives the motor 15 forward and backward is provided.

In addition, a pair of back-up rollers 17.17 for workpieces are arranged opposite to each other at a predetermined interval with a 7-shaped notch in between, and this roller holder 13 has a pin 1.
3a to the frame 12.

As shown in FIG. 1, a shaftless burnish roller 18 is disposed in the center of the front end (left end in FIG. 1) of the trolley 15, and this burnish roller 18 is attached to the crankshaft to be burnished. A backup roller 19 is disposed at a position opposite to the contact position with the rotation center line C across the rotation center line C of the vanish roller 18, and rotation shafts 20a, 20a each inclined in a plane including the rotation center line C of the vanish roller 18. It is supported rotatably by being sandwiched from three directions by a pair of conical rollers 20 and 20 having the same shape and made of a low elastic modulus material such as a resin having the following properties. Further, both conical rollers 20, 20 are arranged with their small diameter sides and large diameter sides facing oppositely at a position away from the contact position of the crankshaft W on the outer peripheral surface of the burnish roller 18 by an angle of less than 90 degrees. At the same time, it is arranged so as to be in constant pressure contact with the vanish roller 18 due to the slight elasticity of the resin, thereby preventing the rotation center of the vanish roller 18 from shifting and also preventing it from escaping to the front side. Further, in FIG. 1, reference numeral W1 is a balance weight of the crankshaft W (the shape is shown by a two-dot chain line), and the diameter of the backup roller 19 is determined so that this balance weight W1 does not interfere with the rotating shaft 19a. Ru.

In addition, as described above, the trolley 15 and the roller holder 1
3 is attached, slide rails 21 and 21 are provided on the base end side (on the right side in FIG. 3), one above the other in parallel to each other, and are slidably inserted into the floating bracket 22. The lower part of the floating bracket 22 is rotatably supported by a pin 23, and is allowed to swing vertically about the pin 23 and slide horizontally in FIG. 3 at the same time. There is.

On the other hand, the crankshaft W to be machined by this roller burnishing machine 11 is set on the machine mount 24 so that the center line of the journal part J, which is the center of rotation, is horizontal, as shown in FIG. A pair of spindles 25.26 are arranged facing each other on both sides of the processing machine stand 24, and each spindle 25.26 has a chuck device 27.2.
8 are respectively attached, and the crankshaft W has its both ends connected to the respective centers 27a, 27 and 28 of both chuck devices 27, 28,
, 28a. Further, a rotary encoder 29a is provided on the outside of one spindle 25.
Servo motor 2 whose start and stop are precisely controlled by
9 is provided to drive the spindle 25 at a reduced speed.

Further, the chuck device 27 attached to the spindle 25 is provided with a chipped portion 3o so as to rotate together with the chuck device 27, and by fixing the chipped portion 30 to the crankshaft W, Double chuck device 27
．． 28 center 27a.

The spindle 25 is attached to the crankshaft W supported between the spindles 28a and 28a.
torque is reliably transmitted.

Further, a control device 31 and a hydraulic power source 32 for driving a hydraulic cylinder 16 are connected to the roller burnishing machine 11 disposed at a predetermined position on the processing machine frame 24 on which the crankshaft W is set. At the same time, the control device 31 has
Data such as the pressing force of the vanish roller 18, the amount of movement of the trolley 15, and the rotation angle of the crankshaft W detected by the rotary encoder 31a provided on the spindle 25 are input, and the input data Based on this, a control signal is sent to a servo valve (not shown) of the hydraulic cylinder 16. Further, the control device 31
Based on the data of the position in the rotational direction of the oil hole formed in each journal part J and each pin part P of the crankshaft W to be burnished, the burnish roller 18 is set at the position of each oil hole. The machine is equipped with a load pattern control program that reduces the machining load to a predetermined pressure, thereby preventing excessive depression of the machined surface due to an increase in surface pressure around the oil hole.

Next, the operation of this embodiment configured as described above will be explained.

The roller burnishing machine 11 is arranged so that the moving direction of the trolley 15 to which the burnish roller 18 is attached is perpendicular to the center line of the crankshaft W set on the processing machine stand 24, that is, the direction of movement of the trolley 15 to which the burnish roller 18 is attached is aligned with the crankshaft. The roller holder 13 is attached and detached, and the journal part J or pin part P of the crankshaft W is installed so as to be perpendicular to the center line of the crankshaft W.
7.17.

Then, when the trolley 15 is advanced by the hydraulic cylinder 16 to press the burnish roller 18 against the workpiece surface with a predetermined pressure, and the two servo motors are started to rotate the crankshaft W, the crankshaft W rotates. The surface to be machined is plastically processed to be smooth by the burnish roller 18 which is transmitted and rotates and contacts with high pressure.

The shaftless burnish roller 18, which rotates by being transmitted with the rotation of the crankshaft W, receives the pressing force against the crankshaft W by the backup roller 19, and rotates while being in contact with the outer peripheral surface of the burnish roller 18. A pair of conical rollers 20° 20 are connected to each rotating shaft 20a.
is disposed within a plane that includes the rotation center line C of the vanish roller 18, so that the tangents between the vanish roller 18 and each conical roller 20, 20 are aligned with the vanish roller 1.
It becomes parallel to the rotation center line C of 8.

Therefore, a tangential force t is generated on each conical roller 20, 20 rotating in contact with the burnish roller 18 (see FIG. 2). This tangential force t acts in the same manner as in the adjusting wheel of a centerless grinding machine that performs feeding processing, for example. the result,
A pair of conical rollers 20.20 of the same shape are brought into contact with the outer circumferential surface of the burnish roller 18 with their large diameter side and small diameter side opposite to each other, so that each conical roller 20.
The tangential force t generated by 0.20 is the vanish roller 1
8 acts as a moment in the same direction. As a result, the vanish roller 18 is held between the conical rollers 20 and 20 by the moment, and its movement in the thrust direction is restricted.

Further, since the conical rollers 20.20 are in contact with the vanish roller 18 at a position less than 90 degrees from the contact position of the vanish mouth 18 with the crankshaft W, the vanish roller 18 is in contact with the pair of conical rollers 20, 20. 20 and backup roller 19, and therefore, even if the contact with crankshaft W is released, it will not move in the radial direction and fall off from trolley 15.

Note that the crankshaft W rotates around the center line and does not fluctuate, but when performing burnishing on the pin part P, which rotates around the center line while drawing a locus of a constant radius, the roller burnish Since the processing machine 11 is installed so that it can simultaneously swing vertically and slide forward and backward using the pin 23 as a fulcrum, it can draw a locus of a constant radius around the center line. It automatically swings and slides following the movement of the rotating pin part P, making it possible to perform burnishing.

Then, by actually using this burnishing machine 11, 5
The pin part P and journal part J of the crankshaft W of an automobile four-cylinder engine made of quenched and tempered material made of 55C were burnished, and as a comparative example, the respective results were compared with those in which the pin part P and journal part J were finished by grinding by lapping, etc. The results are shown in Table 1.

The burnishing conditions were as follows: surface pressure was Hertzian contact stress of 120 kgf/-, and crank rotation speed was 3 Orpm.

Table 1 As can be seen from Table 1, the surface roughness was significantly improved, and there was no adverse effect on roundness and straightness due to burnishing.

Further, during the burnishing process, due to the action of the pair of conical rollers 20, 20, problems such as falling off of the burnishing roller 18 or misalignment in the thrust direction did not occur.

As described above, in this embodiment, the pair of conical rollers 2
Since the rollers 0 and 20 are made of a low elastic modulus material such as resin, the smooth surface of the burnish roller 18 will not be damaged, and each rotating shaft 20a of the conical roller 20, 20 will not be damaged.
, 20a can be avoided. Also, a pair of conical rollers 20, 20 are connected to the vanish roller 1.
Since the burnish roller 18 is provided so as to be in contact at a position less than 90 degrees from the work contact position on the outer peripheral surface of the burnish roller 18, the burnish roller 18 is always held between the two conical rollers 20, 20 and the backup roller 19. Therefore, falling off when the contact with the workpiece is released can be prevented.

In addition, in this embodiment, a pair of conical rollers 20.2
0 is made of a low elastic modulus material such as resin, the pair of conical rollers 20 and 20 may be made of steel, and the support system of each conical roller may have a structure with spring characteristics. You can also.

Further, in this embodiment, a case has been described in which a pair of conical rollers 20, 20 are used, but it is also possible to use a plurality of pairs of conical rollers for support. Similar effects can be obtained by using a chain-shaped roller such as a curved roller.

Further, in this embodiment, the case where there is one burnish roller 18 has been described, but even when there are a plurality of burnish rollers 18, it can be suitably implemented by providing the same support structure for each.

Effects of the Invention As explained above, the shaftless roller support structure of the present invention is arranged so as to come into contact with the circumferential surface of the shaftless roller at a position that receives the contact pressure of rotating or moving members in a well-balanced manner. A backup roller having a structure supported by a backup roller and a pair or more of conical rollers or chain-shaped rollers arranged so as to be in contact with the circumferential surface of the roller with the small diameter side and the large diameter side facing in opposite directions. Therefore, movement of the axisless roller in the thrust direction can be effectively prevented.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, and FIG. 1 is a side view showing the support structure of the burnish roller;
Figure 2 is a view from the ■ arrow in Figure 1, Figure 3 is a side view showing the floating mechanism of the burnishing machine, and Figure 4 is a view of the burnishing machine attached to the machine stand with the crankshaft set. 5 to 8 show a conventional example, FIG. 5 is a perspective view showing one of the conventional support structures for an axisless roller, and FIG. 6 shows the roller support structure of a conventional burnishing machine. FIG. 7 is a side view showing a crankshaft burnishing method, and FIG. 8 is a schematic explanatory diagram showing a conventional shaftless roller support structure. 11...Roller burnish processing machine, 13...Roller holder, 15...Trolley 16...Hydraulic cylinder, 17...Backup roller for work, 1
8... Vanish roller, 19... Backup roller, 20... Conical roller, 25.26
...Spindle, 27.28...Chuck device, 31...Control device, 32...Hydraulic power source, W.
・・Crankshaft, ・・Balance weight, ゛1 lateral part, ・・Pin part, t: tangential force.

Claims (1)

[Claims] In a support structure for an axisless roller that is rotationally driven in contact with a rotating or relatively moving member, the axisless roller is located at a position on the roller peripheral surface that receives the contact pressure of the rotating or moving member in a well-balanced manner. a backup roller disposed so as to come into contact with the roller, and a pair or more of conical rollers or a pair of conical rollers disposed so as to come into contact with the circumferential surface of said roller with their small diameter side and large diameter side facing in opposite directions. A support structure for an axisless roller, characterized in that it is supported by a shaped roller.