JP2012187676A - Grinding tool for honing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinding tool with an excellent cooling effect on a processed surface and the discharging efficiency of ground powder of slits and which is capable of easily processing a coolant flow path without reducing the rigidity of a holder body and a tapered cone.SOLUTION: The grinding tool includes: the columnar holder body with several slits in the peripheral direction; the tapered cone contained coaxially with the holder body; hone shoes supported by the cone and contained inside each of the several slits; and hones installed on the shoes and projected from the holder body in the radius direction. The shoes are capable of freely moving by the movement of the cone in the shaft direction. The holder body is provided with a coolant flow entrance which supplies the coolant into the holder body and several discharging grooves formed on the slits which discharge the coolant flowed into the holder body. A space is formed between the inner periphery surface of the holder body and the outer periphery surface of the cone due to the difference of the diameter of each of them, and the coolant flow path is formed at a part of the tapered section of the cone where the bottom parts of the shoes do not abut.

Description

  The present invention relates to a honing grinding tool with improved properties.

  A grinding tool called a honing holder is used for grinding a member having a recessed oil sump groove such as a cylinder bore of an automobile internal combustion engine. In this grinding tool, a plurality of grindstones are attached to slits formed in a rotatable honing holder main body via holders (grinding shoe) that radiate from the rotation shaft, and the holder main body is rotated and reciprocated in the axial direction. The inner peripheral surface of the workpiece is ground by moving the workpiece.

  In a conventional honing machine, a technique is known in which coolant is supplied to a grinding surface in order to cool heat generated by friction between a grindstone and a workpiece in a roughing process and a finishing process.

  Among them, a technique is known in which the coolant supply means is not provided separately from the honing holder, but is integrated, the supply channel is formed inside the honing holder body, the coolant is circulated, and the coolant is supplied to the grinding surface. (For example, see Patent Documents 1 and 2).

  In the honing holder described in Patent Document 1, a coolant flow path is formed inside a tapered cone provided in the holder main body for adjusting the advancing and retreating of the grindstone in the radial direction of the rotation axis. The coolant supplied from is discharged from the gap between the slit of the holder body and the grindstone to the external machining surface via this flow path.

  Further, in the honing holder described in Patent Document 2, the coolant flow path similarly passes through the honing holder, but the coolant flow path formed of a spiral groove is formed on the inner peripheral surface of the holder main body, The coolant is supplied to the processing surface by this flow path.

  According to these techniques, the coolant is discharged from the slit near the processing point, so that the cooling effect can be improved, and the grinding powder that has conventionally entered the holder body through the gap between the holder body and the grindstone in the slit. Can be discharged to the outside.

Japanese Patent Publication No. 7-4759 Japanese Patent No. 4119067

  However, the honing holder described in Patent Document 1 has a problem in that since the flow path is processed inside the tapered cone, the processing is difficult and the rigidity of the tapered cone is reduced. Also, in the honing holder described in Patent Document 2, since a groove-shaped flow path is processed on the inner peripheral surface of the holder main body, high-precision processing is difficult, and the holder main body has many slits for attaching a grindstone. Since it is formed, the rigidity is originally not sufficient, but there is a problem that the rigidity is further reduced by processing the groove-shaped flow path.

  The invention of the present application has been made in view of the above situation, and of course, the cooling effect on the processed surface and the discharge of grinding powder from the slits are good, as well as reducing the rigidity of the honing holder main body and the tapered cone. An object of the present invention is to provide a grinding tool that can easily and easily process a coolant channel.

  The present invention relates to a cylindrical holder body having a plurality of slits in the circumferential direction, a tapered cone contained coaxially with the holder body, a grinding wheel shoe supported by the tapered cone and contained in each of the plurality of slits, and a grinding stone A grinding tool that is attached to the shoe and includes a grindstone that protrudes in the radial direction from the holder main body, and the grindstone shoe can be advanced and retracted in the radial direction by advancing and retreating in the axial direction of the taper cone. A coolant inlet for supplying coolant and a plurality of discharge grooves formed in a slit for discharging the coolant that has flowed into the holder main body are provided between the inner peripheral surface of the holder main body and the outer peripheral surface of the tapered cone. A gap due to the difference between the two is formed, and a coolant flow path is formed in a portion of the tapered portion of the tapered cone where the bottom of the grindstone shoe does not contact. It is characterized by a door.

  In this invention, it is set as the preferable aspect that the discharge flow rate for every slit is substantially uniform by adjusting the cross-sectional area of a discharge groove and a coolant inflow port.

  In the present invention, a plurality of taper cones provided coaxially are provided, each taper cone abuts the bottom of a different group of grindstone shoes depending on the application, and the outer tapered cone inner circumferential surface and the inner tapered cone outer circumferential surface It is a preferred embodiment that a gap is formed between the two in diameter.

  In the present invention, the coolant that has flowed into the holder through the coolant inlet formed in the holder main body is a gap formed by the difference in diameter between the inner peripheral surface of the holder main body and the outer peripheral surface of the tapered cone, or the inner peripheral surface of the outer tapered cone. Since a gap due to the difference in diameter between the two and the inner tapered cone outer peripheral surface can be circulated, there is no need to process a complicated groove on the inner peripheral surface of the holder body as in the prior art, and the flow path can be easily Can be formed. Moreover, since the discharge groove is formed in the slit including the grindstone, the coolant can be discharged from a desired location close to the processing point. Furthermore, since the flow path is formed in the taper portion of the taper cone, the coolant that has circulated from the holder main body base end side can also reach the holder main body tip end side, and thereby, the slit base end side and The coolant can be discharged uniformly from any of the front end sides.

  In the present invention, the discharge flow rate for each slit can be adjusted by adjusting the cross-sectional area of the discharge groove in the slit and the coolant inlet in the tapered portion, so the flow rate is uniform in all slits. It is also possible to change the flow rate individually if it is necessary to change it for each application of the grindstone to be held.

It is a perspective view which shows the grinding tool of this invention. It is a disassembled perspective view which shows the grinding tool of this invention. It is the figure seen from the direction B in FIG. It is a perspective view which shows the holder main body of the grinding tool of this invention. It is a perspective view which shows the outer side taper cone of the grinding tool of this invention. It is a perspective view which shows the inner side taper cone of the grinding tool of this invention. It is the sectional view on the AA line in FIG. It is sectional drawing which shows the holder main body of the grinding tool of this invention. It is sectional drawing which shows the outer side taper cone of the grinding tool of this invention, (b) is CC sectional view taken on the line of (a). It is sectional drawing which shows the inner side taper cone of the grinding tool of this invention, (b) is the DD sectional view taken on the line of (a).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Diagram 1 of the grinding tool is a perspective view of the grinding tool H of the present invention, FIG. 2 shows an exploded perspective view. 4 to 6 are detailed enlarged views of each member (holder main body, outer tapered cone, inner tapered cone), and FIGS. 8 to 10 are sectional views thereof. Further, FIG. 7 is a perspective view of the assembled state.

  The grinding tool H includes a holder main body 10 having a cylindrical head for grinding, an outer tapered cone 20 coaxially included in the holder main body 10, and an inner tapered cone included coaxially in the outer tapered cone 20. 30. A plurality of slits 11a and 11b are formed in the cylindrical portion 15 of the holder main body 10 in the circumferential direction, and a grindstone portion 40 and 41 are included in each of the slits 11a and 11b so as to slightly protrude in the radial direction. . The base end side 16 of the holder main body 10 is connected to a known rotation mechanism (not shown), and the workpiece is ground by rotating the holder main body 10 itself.

  The grindstone portion includes a rough grindstone portion 40 for rough grinding and a finish grindstone portion 41 for finishing, and the rough grindstone 40a and the finish grindstone 41a are respectively supported by the grindstone shoes 40b and 41b (hereinafter, referred to as “the grindstone”). They are distinguished only by reference numerals and may simply be abbreviated as “whetstone portions 40, 41” and “whetstones 40a, 41a”). In FIG. 2, some of the grindstone portions are shown as representatives, but in practice, the grindstone portions are included in all the slits 11 a and 11 b.

  This is shown in FIG. FIG. 3 is a view as seen from the direction B in FIG. 2, and the grindstone portions 40 and 41 are inserted into the slits as shown in FIG. Among these, the grindstone portion 40 has a relatively short leg grindstone shoe 40 b, and the grindstone shoe 40 b passes through the slit 11 a of the holder body 10 and supports the bottom portion by the tapered portions 22 a and 22 b of the outer tapered cone 20. Then, the grindstone shoe engaging portion 40c is engaged with the engaging portion 26 of the outer tapered cone 20 to prevent the falling from the slit 11a.

  The grindstone portion 41 has a relatively long leg grindstone shoe 41 b. The grindstone shoe 41 b penetrates the slit 11 b of the holder body 10, and further penetrates the through hole 21 of the outer tapered cone 20, and the inner tapered cone 30. The bottom portions are supported by the taper portions 31a and 31b, and the grindstone shoe engaging portion 41c engages with the engaging portion 34 of the inner tapered cone 30 to prevent the slit 11b from falling off.

  As shown in FIG. 3, when viewed in a cross section in the radial direction, the grindstone portion 41 is disposed in a cross shape, and the grindstone portion 40 is disposed so as to be adjacent to both sides or one side of the grindstone portion 41. However, the arrangement of the rough grindstone and the finishing grindstone in the present invention is not limited to this order.

  As shown in FIGS. 9A and 10A, the grindstone shoe 40 b is in contact with the tapered portions 22 a and 22 b of the outer tapered cone 20, and the grindstone shoe 41 b is the tapered portions 31 a and 31 b of the inner tapered cone 30. Abut. Furthermore, although the grindstone shoes 40b and 41b are free in the radial direction by fitting into the slits 11a and 11b, the movement in the axial direction is restricted.

  Therefore, when the outer tapered cone 20 and / or the inner tapered cone 30 are slid in the axial direction, the grindstone portion can be moved forward and backward in the radial direction by sliding between the tapered portion and the grindstone shoe bottom. Specifically, the grindstone portion can be moved radially outward when the taper cone is slid in the upward direction in the drawing, and radially inward when the taper cone is slid downward in the drawing. Thereby, the protrusion amount to the radial direction of a grindstone part can be adjusted.

  Further, since the holder main body 10, the outer tapered cone 20 and the inner tapered cone 30 are independent from each other, only the outer grindstone portion 40 is finished by sliding only the outer tapered cone 20, and only the inner tapered cone 30 is slid. Only the grindstone 41 can be moved independently.

  As shown in FIG. 8, a coolant inlet 13 is formed in the flange portion of the holder body 10, and the supplied coolant passes through the holder body 10 as will be described later via the coolant inlet 13. The slits 11a and 11b containing the grindstone are discharged to the outside of the holder body 10. At this time, discharge grooves 12a and 12b are formed in the slits 11a and 11b, respectively, and when the coolant is discharged from the slits, the coolant is mainly discharged from the discharge grooves 12a and 12b.

  The inner peripheral surface 14 of the holder body 10 shown in FIG. 8 and the outer peripheral surface 24 of the outer tapered cone 20 shown in FIG. 9 are also the inner peripheral surface 25 of the outer tapered cone 20 and the outer peripheral surface 33 of the inner tapered cone 30 shown in FIG. The inner diameter and the outer diameter are adjusted so that a gap is formed between the two in the assembled state.

Operation of the Grinding Tool When the grinding tool H is used, as shown in the perspective view of FIG. 7, the outer taper cone 20 and the inner taper cone 30 are coaxially included in the holder body 10 and the outer taper cone 20, respectively. The Coolant supply from a coolant supply source (not shown) is started and the grinding tool H is rotated to start grinding the workpiece. When roughing is performed, the outer tapered cone 20 is slid to slide the coarse grindstone portion 40, and when finishing is performed, the inner tapered cone 30 is slid to cause the finishing grindstone portion 41 to protrude by a predetermined amount.

  The supplied coolant flows in from the coolant inflow port 13 and circulates in the holder main body 10 through distribution paths X and Y indicated by broken-line arrows in FIG. Here, the symbol X is an outer coolant circulation path, and the symbol Y is an inner coolant circulation path. However, in the right half of the figure, the circulation path X is omitted, and only the circulation path Y is illustrated, and the left side of the figure. In the half, the distribution path Y is omitted, and only the distribution path X is shown. However, this is for simplification of illustration, and in reality both the distribution paths X and Y are coaxial cylindrical distribution. The route is configured.

  The coolant that has flowed in from the coolant inlet 13 is branched into a coolant that is directed to the outer circulation path X and a coolant that is directed to the inner circulation path Y. The coolant toward the outer flow path X first passes through a cylindrical flow path formed by the difference in diameter between the inner peripheral surface 14 of the holder body 10 and the outer tapered cone 24.

Subsequently, the coolant flows to the tip side of the grinding tool H and reaches the tapered portion 22a. However, since the leg portion of the grindstone shoe 40b is in contact with the tapered portion 22a, some of the coolant hinders distribution. It is branched here, flows to the discharge groove 12a formed in the slit 11a, and is discharged to the outside (distribution path X ₁ ).

The remaining coolant passes through the groove portion 23 formed between the tapered portions 22a divided into a plurality of regions shown in FIG. , it is discharged from the discharge groove 12b formed in the slit 11a (distribution channels _{X 2} and _X 3).

  In FIG. 5, the through hole 21 is illustrated in addition to the groove portion 23 between the plurality of tapered portions 22 a, and here, as described above, the grindstone shoe supported by the inner tapered cone 30. Since 41b is penetrated and a distribution | circulation is prevented, a coolant distribute | circulates only on the groove part 23. FIG.

In the present invention, by adjusting the cross-sectional area in the step of forming the groove portion 23, the ratio than the taper portions 22a and distribution paths X ₁ proximal, of the coolant discharge flow rate of the flow path X ₂ and X ₃ of the distal end Can be freely adjusted, and is preferably adjusted to be uniform. In addition, the coolant discharge flow rate can be adjusted by adjusting the cross-sectional area and the number of the discharge grooves 12a provided in the slit 11a.

  Of the coolant that has flowed from the coolant inlet 13, the coolant that is branched from the coolant that is directed to the outer flow path X and that is directed to the inner flow path Y first passes through the hole formed in the outer tapered cone 20, and then the outer tapered cone. 20 flows into the interior. Subsequently, it passes through the cylindrical flow path formed by the difference in diameter between the inner peripheral surface 25 of the outer tapered cone 20 and the inner tapered cone outer peripheral surface 33.

Subsequently, the coolant flows to the tip side of the grinding tool H and reaches the tapered portion 31a. However, since the leg portion of the grindstone shoe 41b is in contact with the tapered portion 31a, some of the coolant hinders circulation. It is branched here, flows into the discharge groove 12b formed in the slit 11b, and is discharged to the outside (distribution path Y ₁ ).

The remaining coolant passes through the groove portion 32 formed between the tapered portions 31a divided into a plurality of regions shown in FIG. 6 where the legs of the grinding wheel shoe 41b abut, and further flows to the tip side of the grinding tool H. Then, the liquid is discharged from the discharge groove 12b formed in the slit 11b (distribution paths Y ₂ and Y ₃ ).

In the present invention, by adjusting the cross-sectional area in the step of forming the groove portion 32, the ratio and distribution path Y ₁ on the base end side of the tapered portion 31a, the coolant discharge flow rate of the distribution channel Y ₂ and Y ₃ of the distal end Can be freely adjusted, and is preferably adjusted to be uniform. In addition, the coolant discharge flow rate can be adjusted by adjusting the cross-sectional area and the number of the discharge grooves 12b provided in the slit 11b.

  Further, in the present invention, since the coolant outer flow path X and the inner flow path Y are independent, the coolant is discharged from the slit 11 a that holds the rough grindstone portion 40 and the slit 11 b that holds the finishing grindstone portion 41. The coolant discharge flow rates can be adjusted independently of each other. For this reason, when there is a difference between the two in terms of the amount of cooling heat required at the processing point and the physical properties of the grinding powder discharged from the slit, there is an effect that the discharge flow rate can be individually adjusted.

  As described above, in the present invention, the coolant flow path includes the gap formed by the difference in diameter between the inner peripheral surface of the holder body and the outer peripheral surface of the tapered cone, and the outer peripheral surface of the outer tapered cone and the outer peripheral surface of the inner tapered cone. Since there is a gap due to the difference in diameter between the two, there is no need to form a complicated groove-like flow path that is difficult to form unlike conventional grinding tools, just by adjusting the inner and outer diameters Good. Moreover, it can suppress that the rigidity of a holder main body or a taper cone is reduced by formation of such a flow path. Moreover, since the discharge groove is formed in the slit including the grindstone, the coolant can be discharged from a desired location close to the processing point. Furthermore, since the flow path is formed in the taper portion of the taper cone, the coolant that has circulated from the holder main body base end side can also reach the holder main body tip end side, and thereby, the slit base end side and The coolant can be discharged uniformly from any of the front end sides. Further, the discharge flow rate can be adjusted by adjusting the cross-sectional area of the discharge groove in the slit and the groove-shaped flow path in the tapered portion.

  Maintenance frequency can be reduced by improving the cooling effect on the machined surface of the grinding tool, improving the discharge of grinding powder from the grinding tool, and suppressing the reduction in the rigidity of the tool. Useful for grinding.

H ... grinding tool,
10 ... Holder body,
11a, 11b ... slits 12a, 12b ... discharge grooves,
13 ... Coolant inlet 14 ... Holder body inner peripheral surface,
15 ... Cylindrical part,
16 ... proximal end side,
20 ... Outer tapered cone,
21 ... through hole,
22a, 22b ... taper part,
23 ... groove,
24. Outer taper cone outer peripheral surface,
25 ... Outer taper cone inner peripheral surface,
26 ... engaging portion,
30 ... Inner taper cone,
31a, 31b ... taper part,
32 ... groove,
33 ... Inner taper cone outer peripheral surface,
34 ... engaging portion,
40: Coarse whetstone part,
40a: Coarse whetstone,
40b ... Whetstone shoe,
40c: Whetstone shoe engaging portion,
41 ... Finishing wheel part,
41a ... finishing wheel,
41b ... Whetstone shoe,
41c: Whetstone shoe engaging portion,
X, X _{1 to} X ₃ ... coolant flow path (outside),
_Y, Y 1 ~Y 3 _... coolant distribution channels (inside).

Claims (3)

A cylindrical holder body having a plurality of slits in the circumferential direction, a tapered cone contained coaxially with the holder body, a grinding wheel shoe supported by the tapered cone and contained in each of the plurality of slits, and the grinding stone A whetstone attached to the shoe and projecting radially from the holder body,
A grinding tool in which the grindstone shoe is capable of moving back and forth in the radial direction by moving back and forth in the axial direction of the taper cone,
The holder body includes a coolant inlet for supplying coolant into the holder body, and a plurality of discharge grooves formed in the slit for discharging the coolant flowing into the holder body.
A gap is formed between the inner peripheral surface of the holder body and the outer peripheral surface of the tapered cone due to a difference in diameter between the two,
A grinding tool characterized in that a coolant channel is formed in a portion of the tapered portion of the tapered cone where the bottom of the grinding wheel shoe does not contact.   The grinding tool according to claim 1, wherein a discharge flow rate for each slit is substantially uniform by adjusting a cross-sectional area between the discharge groove and the coolant inlet. A plurality of tapered cones provided coaxially are provided, and each tapered cone abuts against the bottom of a group of different grinding wheel shoes depending on the application, and the difference in diameter between the outer circumferential surface of the outer tapered cone and the outer circumferential surface of the inner tapered cone. The grinding tool according to claim 1, wherein an air gap is formed.

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