JP6142155B2 - Grinding equipment - Google Patents

Description

  The present invention relates to a grinding apparatus for grinding an object to be ground, and in particular, a grinding apparatus comprising a grinding body that rotates to grind the object to be ground, and a rolling bearing that is interposed between a support shaft and the grinding body. About.

  For example, Patent Document 1 discloses a grinding technique for a machining surface with a limited peripheral space, such as when machining a vane groove extending radially outward from an inner circumferential surface of a cylinder of a rotary compressor. A grinding apparatus is mentioned. In the grinding device disclosed in Patent Document 1, the grinding wheel base and the shaft are integrated to increase rigidity, and the bearing inner ring is rotated and the bearing gap is increased to minimize the deflection of the grinding wheel base and maintain high accuracy for a long period of time. It can be done. Moreover, in the grinding apparatus of patent document 1, the structure similar to the case where a hydrostatic bearing is used is implement | achieved by supplying a grinding fluid in the pocket formed between the grindstone base metal and the grinding head. .

Further, as an improved product of the grinding apparatus of Patent Document 1, a grinding apparatus 100 (hereinafter, a grinding apparatus according to a reference example) 100 shown in FIG. 5 is conceivable. FIG. 5 is a front cross-sectional view showing a state when a grinding operation is performed using the grinding apparatus according to the reference example.
In this grinding apparatus 100, a grindstone disc 112 is rotatably supported on a support shaft 114 via two angular bearings 116 and 118. Here, as shown in FIG. 2, the two angular bearings 116 and 118 are used in a preload state in combination with the back surface. Thereby, it is not necessary to supply the grinding liquid into the pocket formed between the grindstone base metal and the grinding head as in the grinding apparatus of Patent Document 1 to obtain the same effect as the hydrostatic bearing, It is possible to receive a thrust load.

JP-A-10-109260

  However, the angular bearings 116 and 118 are relatively expensive bearings. Further, the general size of the angular bearings 116 and 118 is about 6 mm in inner diameter, and it is difficult to obtain a smaller size. It is. Further, in the grinding apparatus 100 according to the reference example, the grindstone disc 112 is fastened by the bolt 122 to the bearing housing 120 that houses the angular bearings 116 and 118. For this reason, the entire grinding apparatus 100 is increased in size, making it difficult to use the apparatus 100 for grinding a workpiece having a relatively small inner diameter.

  Furthermore, in the grinding apparatus 100 according to the reference example, as shown in FIG. 5, a step 120 b is provided at a midway position of the through hole 120 a formed in the bearing housing 120 to accommodate the angular bearings 116 and 118. Preload is applied to the angular bearings 116 and 118 by sandwiching the angular bearings 116 and 118 between the step 120b and the flange 114a of the support shaft 114 or the nut 114b fastened to the tip of the support shaft 114. doing. As described above, in the grinding apparatus 100 according to the reference example, in order to apply the preload to the angular bearings 116 and 118, it is necessary to perform a machining operation in which the step 120b is provided in the middle position of the through hole 120a of the bearing housing 120. Yes, it takes time to perform the processing.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a grinding apparatus that is more downsized and less expensive.
Another object of the present invention is to provide a grinding apparatus capable of applying a preload to a bearing with a simpler structure.

According to the grinding device of the present invention, the object is that a grinding body that rotates to grind an object to be ground, a support shaft that rotatably supports the grinding body, and the support shaft are inserted so that the support shaft is inserted. a rolling bearing for supporting the support shaft, a grinding device Ru wherein the grinding body, and a contact portion in contact with the object to be ground, through holes located on the support shaft side of the contact portion formed A hole forming portion, and the hole forming portion holds the rolling bearing by fitting the rolling bearing into the through hole, and the rolling bearing is two small-diameter ball bearings, A lubricant flow path further including a collar in which the support shaft is inserted and disposed between the two small-diameter ball bearings in the through hole, and is configured to pass through the support shaft and the collar. The end opening of the flow path is fitted in the through hole It is solved by facing the space located between a certain two of the small-diameter ball bearing.
In particular, the hole forming portion has a cylindrical shape, the contact portion projects outward from the outer periphery of the hole forming portion to form a disk shape, and the hole forming portion and the contact portion are: It is preferable that it is an integrally molded product.
In the above-described grinding apparatus, the grinding body and the member that holds the rolling bearing are integrally formed, and, as in the above-described reference example, the separated grinding body and the member that holds the bearing are fastened. Bolts are unnecessary. As a result, it is possible to realize a more compact grinding apparatus. Moreover, if it is said structure, it will become possible to supply a lubricant to a small diameter ball bearing through the said flow path during grinding operation.

Further, fitting the above grinding apparatus, the small-diameter ball bearing is provided with a flange portion exiting tension to the position and flanged at one end of the thrust direction of the outer ring, each of the two said small ball bearing in the through hole In this state, each of the flange portions may be engaged with an edge portion formed around the through hole in the hole forming portion.
With such a configuration, because of the use of small-diameter ball bearing as a bearing, relatively easy ones following sizes inner diameter 5 mm, and, since it is possible to obtain at low cost, is more compact, less expensive A grinding device can be provided.

Further, in the above grinding apparatus, a threaded portion formed at one end of the support shaft in the axial direction, a nut fitted to the threaded portion, and the other end of the support shaft in the axial direction are stretched like a bowl. and a flange portion which comes in a state where each of the two said small-diameter ball bearing is fitted in the through hole, the flange portion is in contact with the thrust direction one end face of the inner ring of one of the small-diameter ball bearing The nut may be in contact with one end surface in the thrust direction of the inner ring of the other small diameter ball bearing, and the collar may be in contact with the other end surface in the thrust direction of the inner ring of each of the two small diameter ball bearings.
With such a configuration, each small-diameter ball bearing is sandwiched between the collar disposed between the bearings and the flange portion or the nut of the support shaft in a state where the flange portion is locked to the hole forming portion. A preload is applied. As a result, as in the reference example, processing such as providing a step in the middle position of the through hole into which the small diameter ball bearing is fitted becomes unnecessary, and a preload is applied to each small diameter ball bearing with a simpler structure. It becomes possible.

Further, in the above grinding apparatus, it has a grinding body holder that holds the grinding body so that at least a part of the contact portion in the circumferential direction is exposed to the workpiece, and the support shaft is formed by a fastening part. It may be fixed to the grinding body holder.
With this configuration, the support shaft can be stably fixed by fastening the support shaft to the grinding body holder.

In the above grinding apparatus, the flow path, the grinding holder, may be formed so as to pass through the interior of the support shaft and the collar.

Moreover, in said grinding apparatus, in the state which the said grinding body located in the inner hole formed in the cylindrical body as said to-be-ground object, along the radial direction of the said cylindrical body among this inner hole The side wall may be ground by contacting the side wall of the extended groove-shaped hole.
With this configuration, the effect of the present invention is more effectively exhibited. That is, when a grinding body grinds within an inner hole formed in a cylindrical body as an object to be ground, the smaller the inner diameter of the cylindrical body, the smaller the grinding device is required. Therefore, in such a configuration, the effect of the present invention in which a more compact and less expensive grinding apparatus is realized becomes more significant.

According to the present invention, since the grinding body and the member that holds the rolling bearing are integrally formed products, they are more compact than the configuration in which they are separated and bolted. An inexpensive grinding device is realized.
In addition, according to the present invention, it is possible to apply a preload with a simpler structure to the rolling bearing interposed between the grinding body and the support shaft.

It is a perspective view which shows the external appearance of the workpiece | work which is an example of the to-be-ground object which concerns on this invention. It is explanatory drawing which shows the side surface of the grinding device which concerns on one Embodiment of this invention, and the side surface cross section of a workpiece | work. It is a front sectional view showing the state at the time of grinding work using the grinding device concerning one embodiment of the present invention. It is the figure which expanded the bearing periphery among FIG. It is front sectional drawing which shows the state at the time of grinding using the grinding device which concerns on a reference example.

  Hereinafter, drawings will be described for a grinding apparatus according to an embodiment of the present invention (hereinafter, the present grinding apparatus 1). In addition, embodiment described below is for making an understanding of this invention easy, and does not limit this invention. That is, the present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

In describing the present grinding apparatus 1, the workpiece W to be ground by the present grinding apparatus 1 will be described with reference to FIG. 1. FIG. 1 is a perspective view showing the appearance of the workpiece W. FIG.
The workpiece W is an example of an object to be ground, and is used as a cylinder of a rotary compressor after being processed. As shown in FIG. 1, the workpiece W is a cylindrical body, and an inner hole Wa is formed inside thereof. The inner hole Wa is formed so as to penetrate substantially the center of the workpiece W. In this embodiment, the circular hole portion Wb is a circular hole, and the diameter of the workpiece W is continuous with the circular hole portion Wb. A groove-like hole Wc extending in the direction and a relief hole Wd which is continuous with the groove-like hole Wc on the side opposite to the circular hole portion Wb and becomes a relatively small-diameter circular hole.

  The groove-like hole Wc functions as a vane groove when the cylinder of the rotary compressor is completed from the workpiece W. On the other hand, if the surface of the side wall of the vane groove is rough, the vane that reciprocates in the vane groove may be touched, resulting in a defective cylinder for the rotary compressor. For this reason, in the workpiece | work W, it is necessary to grind | polish the surface of the side wall of the grooved hole Wc with high precision. For this reason, this grinding apparatus 1 is used for grinding the side wall of the groove-like hole Wc of the workpiece W.

  Next, the configuration of the grinding apparatus 1 will be described with reference to FIGS. FIG. 2 is an explanatory view showing a side surface of the grinding apparatus 1 and a side surface cross section of the workpiece W. FIG. 3 is a front cross-sectional view showing a state when the grinding work is performed using the present grinding apparatus 1, and corresponds to FIG. FIG. 4 is an enlarged view around the small-diameter ball bearings 8 and 8 in FIG.

  As shown in FIG. 2, the grinding apparatus 1 is driven by a grindstone 2 as a grinding body that rotates to grind a workpiece W, a long grindstone holder 3 that holds the grindstone 2, and a motor (not shown). And the endless belt 5 spanned between the grindstone 2 and the drive pulley 4. When the drive pulley 4 is rotated by the motor, the rotational force is transmitted to the grindstone 2 via the endless belt 5, and the grindstone 2 is driven by the drive pulley 4 to rotate.

Next, the grinding process of the workpiece W by the grinding apparatus 1 will be outlined.
When starting the grinding process of the workpiece W by the grinding device 1, the grinding device 1 is moved in the + X direction in FIG. 2 to approach the workpiece W, and the grinding wheel 2 and its peripheral portion (for example, the grinding wheel holder 3 , The portion adjacent to the vicinity of the grindstone 2) enters the inner hole Wa of the workpiece W. After entering the inner hole Wa, the grindstone 2 is rotated by the cooperation of the drive pulley 4 and the endless belt 5 and then comes into contact with one side wall of the groove-shaped hole Wc. Thereby, the surface of one side wall of the groove-like hole Wc is ground (specifically, polished). Thereafter, by the same procedure, the rotating grindstone 2 comes into contact with the other side wall of the grooved hole Wc, and the surface of the other side wall is also ground.

  By the way, although it is necessary to support the grindstone 2 rotatably, in this grinding apparatus 1, as shown in FIG. 3, it is supported by the support shaft 6 via the rolling bearing. And the grindstone 2 rotates around the support shaft 6 integrally with the outer ring of the rolling bearing. In addition, as mentioned above, since the grindstone 2 and its peripheral part are located in the inner hole Wa of the workpiece W when grinding the side wall of the grooved hole Wc in the workpiece W, the size is compared as a rolling bearing. Small size is required. For this reason, in the present grinding apparatus 1, small diameter ball bearings 8 and 8 are used as rolling bearings. However, a normal small diameter ball bearing cannot hold its position against a load in the thrust direction.

  On the other hand, in the present grinding apparatus 1, as shown in FIG. 3, in the thrust direction of the outer ring of each of the small-diameter ball bearings 8, 8, more strictly, at the end on the outer side, in a bowl shape. An overhanging flange portion 8a is provided. With this configuration, a preload is appropriately applied to each of the small-diameter ball bearings 8 and 8, and the position in the thrust direction can be stabilized.

In particular, the configuration around the grindstone 2 in the grinding apparatus 1 including the small-diameter ball bearings 8 and 8 will be described in more detail.
The grindstone 2 includes a contact portion 22 that comes into contact with the workpiece W, and a hole forming portion 24 that is located on the support shaft 6 side of the contact portion 22 and has a through hole 26 formed therein. As shown in FIG. 3, the contact portion 22 projects outward from the outer periphery of the cylindrical hole forming portion 24 to form a disk shape. Further, as shown in FIG. 3, the outer peripheral surface of the contact portion 22 is cut out in a substantially V shape to form an accommodation groove 22 a of the endless belt 5.

  The hole forming part 24 has a substantially barrel-shaped outer shape and is continuous with the contact part 22. That is, the hole forming part 24 and the contact part 22 are integrally formed products. The hole forming portion 24 holds the two small diameter ball bearings 8 and 8 by fitting the two small diameter ball bearings 8 and 8 into the through hole 26. Thus, in this grinding apparatus 1, the hole formation part 24 functions as a kind of bearing holder. In other words, in the grinding apparatus 1, a portion corresponding to the bearing housing in the grindstone 2 and a contact portion between the workpiece (that is, a grinding portion) are constituted by one member. As a result, in the grindstone 2, the grinding device 1 can be reduced in size as compared with the configuration in which the portion corresponding to the bearing housing and the contact portion of the workpiece are separate from each other and are fastened by bolts or the like. The

The grindstone holder 3 corresponds to a grinding body holder, and is constituted by two block portions 3a and 3a arranged at positions where the grindstone 2 is sandwiched as shown in FIG. The grindstone holder 3 is arranged such that when the grindstone 2 and its peripheral portion are positioned in the inner hole Wa of the workpiece W, at least a part of the contact portion 22 of the grindstone 2 in the circumferential direction is exposed to the workpiece W. Hold. More specifically, when the grindstone 2 and its peripheral portion are located in the inner hole Wa of the workpiece W, the portion located below the hole forming portion 24 of the contact portion 22 is the groove-shaped portion Wc. The grindstone holder 3 holds the grindstone 2 so as to face the side wall.
A cavity 3b through which the lubricant flows is formed inside the block portion 3a, and the cavity 3b constitutes a part of a lubricant flow path 30 to be described later.

  The support shaft 6 rotatably supports the grindstone 2 and is inserted into insertion holes formed in the inner rings of the small diameter ball bearings 8 and 8. The small diameter ball bearings 8 and 8 support the support shaft 6 by inserting the support shaft 6 into an insertion hole formed in the inner ring. The support shaft 6 is fixed by being fastened to the block portion 3a of the grindstone holder 3 by a fixing bolt 12 as a fastening part.

The structure of the support shaft 6 will be described in detail. A screw portion 6a is formed at one end in the axial direction, and a hook-like portion 6b protruding in a hook shape is located at the other end in the axial direction. The bowl-shaped portion 6b has an outer diameter that is substantially the same as the outer diameter of the flange portion 8a formed on the outer ring of the small-diameter ball bearings 8 and 8. Further, a nut 9 is fitted to the screw portion 6a, and the outer diameter of the nut 9 is somewhat larger than the outer diameter of the outer ring of the small-diameter ball bearings 8 and 8.
A cavity 6 c through which the lubricant flows is formed inside the support shaft 6. When the support shaft 6 is fastened to the block part 3a of the grindstone holder 3 by the fixing bolt 12, the cavity 6c communicates with the cavity 3b on the block part 3a side, and constitutes a lubricant flow path 30 together with the cavity 3b. .

  The small-diameter ball bearings 8 and 8 are relatively small-sized and inexpensive rolling bearings. For example, the inner diameter of the inner ring is about 5 mm, and the outer diameter of the outer ring (strictly outside the portion excluding the flange portion 8a). (Diameter) is about 14 mm.

Further, as described above, the small-diameter ball bearings 8 and 8 include the flange portion 8a at one end portion in the thrust direction of the outer ring. The flange portion 8 a has an outer diameter larger than the diameter of the through hole 26 formed in the hole forming portion 24 of the grindstone 2. One of the two small diameter ball bearings 8, 8 is fitted from one opening side to the through hole 26 formed in the hole forming portion 24 of the grindstone 2, and the two small diameter ball bearings 8. , 8 is fitted into the through hole 26 from the other opening side. In such a state, the flange portions 8a of the two small-diameter ball bearings 8 and 8 are locked to the edge portion 28 formed around the through hole 26 in the hole forming portion 24 as shown in FIG.

  As shown in FIG. 3, a collar 10 is disposed between the two small-diameter ball bearings 8 in the thrust direction (axial direction). The collar 10 has a support shaft 6 inserted therein and is disposed between the two small-diameter ball bearings 8 and 8 in the through hole 26. When the support shaft 6, the small diameter ball bearings 8, 8 and the collar 10 are all assembled to the grindstone 2, the support shaft 6 and the collar 10 apply a preload to the small diameter ball bearings 8, 8. Become.

More specifically, each of the two small diameter ball bearings 8 and 8 is fitted into the through hole 26, the collar 10 is disposed between the small diameter ball bearings 8 and 8, and the support shaft 6 is the small diameter ball bearings 8 and 8. And the nut 9 is fitted in the front-end | tip part by being inserted in the collar | collar 10. As shown in FIG. In this state, as shown in FIG. 4, the hook-shaped portion 6 b of the support shaft 6 abuts against one end surface 8 b in the thrust direction of the inner ring of one small diameter ball bearing 8, and the nut 9 is the inner ring of the other small diameter ball bearing 8. It is in contact with one end surface 8b in the thrust direction. Here, the thrust direction one end face 8b is an end face located on the outer side among the thrust direction end faces. Further, the collar 10 is in contact with the other end face 8c in the thrust direction of the inner ring of each of the two small-diameter ball bearings 8 and 8. Here, the thrust direction other end face 8c is an end face located on the inner side of the thrust direction end faces.
As a result, each of the small-diameter ball bearings 8 and 8 is sandwiched between the collar 10 and the flange portion 6b or the nut 9 of the support shaft 6 to be preloaded. As a result, each of the small-diameter ball bearings 8 and 8 can maintain the position with respect to the load in the thrust direction.

  In addition, with the structure demonstrated above, in this grinding apparatus 1, it becomes possible to give a preload with respect to each small diameter ball bearing 8 and 8 with a simpler structure. If it explains easily, as a structure which gives a preload with respect to the normal small diameter ball bearings 8 and 8 which do not have the flange part 8a, like the structure shown in FIG. 4 (namely, structure of a reference example), it is a through-hole. Although it is conceivable to provide a step at an intermediate position, in order to provide the step, a step forming process is performed on the grindstone 2 and much labor is required.

  On the other hand, in the present grinding apparatus 1, since the small diameter ball bearings 8 and 8 are provided with the flange portion 8a, the small diameter ball bearings 8 and 8 are not required to have a step in the middle position of the normal through hole 26. On the other hand, it is possible to apply a preload. As described above, the present grinding apparatus 1 does not require the work of forming the step, and the manufacturing cost of the apparatus can be reduced accordingly.

  Note that a cavity 10a (a cavity having a cross-shaped cross section or a T-shape in FIG. 3) through which the lubricant flows is formed inside the collar 10. When the support shaft 6 is inserted to a predetermined position with respect to the collar 10, the cavity 10 a communicates with the cavity 6 c on the support shaft 6 side and constitutes a lubricant flow path 30 together with the cavity 6 c.

  When the assembly of the grinding apparatus 1 is completed, the cavity 3b formed in the block portion 3a of the grindstone holder 3, the cavity 6c on the support shaft 6 side, and the cavity 10a of the collar 10 are continuous, and the lubricant A flow path 30 is formed. This flow path 30 is formed so as to pass through the inside of the grindstone holder 3, the support shaft 6 and the collar 10, and the end opening thereof is the two small-diameter ball bearings 8, 8 that are fitted in the through holes 26. Facing the space between them. Lubricating oil mist as a lubricant is supplied to each of the small-diameter ball bearings 8 and 8 through the flow path 30 so that the bearings 8 and 8 are well lubricated.

1 grinding machine 2 grinding wheel 3 grinding wheel holder 3a block part, 3b cavity 4 drive pulley 5 endless belt 6 support shaft 6a screw part, 6b bowl-like part, 6c cavity 8 small diameter ball bearing 8a flange part 8b thrust direction end face 8c thrust direction The other end face 9 Nut 10 Collar 10a Cavity 12 Fixing bolt 22 Contact part 22a Housing groove 24 Hole forming part 26 Through hole 28 Edge 30 Channel 100 Grinding device 112 Grinding wheel disc 114 Support shaft 114a Saddle part, 114b Nut 116, 118 Angular Bearing 120 Bearing housing 120a Through hole, 120b Step 122 Bolt W Work Wa Inner hole, Wb Circular hole, Wc Groove hole, Wd Relief hole

Claims (7)

A grinding body that rotates to grind the workpiece,
A support shaft for rotatably supporting the grinding body;
A rolling bearing said support shaft for supporting the supporting shaft by being inserted, a grinding apparatus Ru provided with,
The grinding body has a contact portion that contacts the object to be ground, and a hole forming portion that is located closer to the support shaft than the contact portion and in which a through hole is formed,
The hole forming portion holds the rolling bearing by fitting the rolling bearing into the through hole ,
The rolling bearing is two small diameter ball bearings,
The support shaft is inserted, and further includes a collar disposed between the two small diameter ball bearings in the through hole,
A flow path of a lubricant formed so as to pass through the inside of the support shaft and the collar;
The end opening of the flow path faces a space located between the two small-diameter ball bearings fitted in the through hole . The hole forming portion has a cylindrical shape,
The contact portion projects outward from the outer periphery of the hole forming portion to form a disk shape,
The grinding apparatus according to claim 1, wherein the hole forming portion and the contact portion are integrally formed products. The small-diameter ball bearing includes a flange portion that is located at one end portion in the thrust direction of the outer ring and projects in a hook shape,
In the state where each of the two small diameter ball bearings is fitted in the through hole, each of the flange portions is locked to an edge portion formed around the through hole in the hole forming portion. The grinding apparatus according to claim 2. A threaded portion formed at one axial end of the support shaft;
A nut that fits into the thread portion;
And a flange portion exiting tension to the position and flanged in the axial direction other end side of the support shaft,
In a state where each of the two small-diameter ball bearings is fitted in the through hole, the flange portion abuts against one end surface in the thrust direction of the inner ring of one small-diameter ball bearing, and the nut is the other small-diameter ball bearing. The grinding apparatus according to claim 3, wherein the inner ring is in contact with one end surface in the thrust direction, and the collar is in contact with the other end surface in the thrust direction of the inner ring of each of the two small-diameter ball bearings. A grinding body holder for holding the grinding body such that at least a part of the contact portion in the circumferential direction is exposed to the workpiece;
The grinding apparatus according to claim 4, wherein the support shaft is fixed to the grinding body holder by a fastening part. The flow path, the grinding apparatus according to claim 5, characterized in that it is formed so as to pass through the grinding holder, the inside of the support shaft and the collar. Abutting on the side wall of the groove-shaped hole extending along the radial direction of the cylindrical body in the state of being positioned in the internal hole formed in the cylindrical body as the object to be ground The grinding apparatus according to any one of claims 1 to 6, wherein the side wall is ground by means of grinding.

Images