JP2000006001A - Honing head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the truing accuracy of a high hardeness honing grinding wheel which consists of a diamond grinding wheel, a CBN grinding wheel, or the like. SOLUTION: Center holes 15 and 16 are formed at both end faces of an expansion rod 9 which expands and contracts a honing grinding wheel 7 together with a grinding wheel shoe 6. After regulating to be in a specific expansion condition by using an adjust nut 29, the whole body of a honing head 1 is supported at both sides by the centers 32 and 33 of a cylindrical grinding board by using the center holes 15 and 16, so as to grind by a truing grinding wheel G. In the honing processing time, a push rod is connected to a female screw part 17, as well as the adjust nut 29 is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a honing head for honing and, more particularly, to improving the truing accuracy of a honing wheel when performing honing using a high-hardness grindstone such as a diamond grindstone or a CBN grindstone. Regarding the honing head that was planned.

[0002]

2. Description of the Related Art In the bore honing of a cylinder block of an internal combustion engine, in order to improve the grinding efficiency and extend the life, a honing stone using diamond abrasive grains or CBN abrasive grains having a high stone hardness is used. It is used.
On the other hand, these diamond wheels and CBN wheels are
The wear of the grindstone itself is small, but the shape familiarity with the cylinder bore is poor, and it is common to use it after truing (truing).

FIG. 8 shows an example of a truing method of a conventional honing head. A honing head 101 is formed mainly of a hollow cylindrical head body 104 comprising a holder 102 and a joint member 103 as is well known. A plurality (even number) of honing grindstones 106 held by a grindstone shoe 105 are radially arranged so as to face each other.
An expansion rod 108 having a tapered cone portion 107 that is in tapered contact with each of the grindstone shoes 105 is inserted in 04. The expansion rod 108 is urged rightward in FIG.
Each honing grindstone 106 is urged in a contraction direction by a return spring 110, and at the time of honing processing, each honing grindstone 106 is expanded in the radially expanding direction by sliding the expansion rod 108 together with the push rod 111 to the left in the drawing. You.

On the other hand, during truing, an adapter 112 is connected to the joint member 103 of the head main body 104, and the push rod 111 is pressed by a grinding stone expanding push screw 113 attached to the adapter 112, thereby causing the expansion rod 108 to move. The honing grindstones 106 are slid in the left direction, and the respective honing grindstones 106 are extruded in the radial direction so that the facing dimension a of the honing grindstones 106 facing each other becomes a predetermined value by sliding contact between the tapered cone portion 107 and the grindstone shoes 105. Using the center hole 114 provided in the lower end of the head main body 104 and the center hole 115 provided in the joint member 112, the center 11 on the cylindrical grinding machine side is used.
At 6,117, the honing head 101 is supported at both ends, and then cylindrical grinding is performed with a truing grindstone G also serving as dressing.

[0005]

In the structure of the honing head 101 shown in FIG. 8, the extension rod 108 is inserted into the inner peripheral surface of the head main body 104 with a predetermined fitting gap, and a joint member is provided. 112 is also attached to the holder 102 with a predetermined fitting gap so that it can be disassembled and maintained, and the adapter 112 is also attached to the joint member 103 with a predetermined fitting gap so that it can be easily attached and detached. Each fitting gap is gradually enlarged due to wear due to use.

The center of rotation during truing, that is, during cylindrical grinding, is determined by the center holes 114 and 115. However, the above-described accumulation of the fitting gaps appears as deflection of the outer diameter of the honing grindstone 106 and expands. The deviation from the above-mentioned deflection occurs in the dimension from the axis of the rod 108 to the surface of each honing stone 106. As a result, a good contact state of the honing grindstone 106 cannot be obtained at the time of actual honing processing, and there is a limit in improving the accuracy of the work side such as roundness, cylindricity, and surface roughness.

[0007] Other truing methods are disclosed in, for example, Japanese Patent No. 2668722 and Japanese Patent Application Laid-Open No. 9-856.
No. 23 has also proposed a method.

However, since the former does not perform truing on the entire honing head but performs truing after replacing each honing grindstone with a dedicated tool, not only the necessity of reassembling work but also the same as above is required. In addition, it is not possible to expect improvement in accuracy such as roundness of the entire honing head. In the latter method, a dress member similar to a work is periodically flowed to a honing line to perform dressing. Therefore, when it is necessary to change a tool, it is necessary to flow a dress member to the line each time. There is a fear that the setup time may be redundant.

The present invention has been made in view of the above-mentioned problems, and does not require special tools or reassembly of parts, and can obtain high-precision truing accuracy despite truing by general cylindrical grinding. It is intended to provide a structure of the honing head itself.

[0010]

According to a first aspect of the present invention, a plurality of honing whetstones each held by a whetstone shoe are radially arranged on a hollow cylindrical head body, and the head body has Honing in which each honing stone is expanded or contracted in the radial direction of the head main body by inserting an expansion rod having a taper cone portion that is in taper contact with each grinding shoe, and sliding this expansion rod in the axial direction of the head main body. In the head,
At the upper and lower ends of the extension rod, a center hole for supporting the extension rod at both ends by center work is formed,
A push rod is detachably connected to an upper end of the extension rod to extend the extension rod.

According to a second aspect of the present invention, a screw hole is formed at the back of the center hole formed at the upper end of the expansion rod according to the first aspect of the present invention, and a push rod is formed in the screw hole. It is characterized by being connected so as to be screwed.

According to a third aspect of the present invention, the lower end of the extension rod according to the first or second aspect projects from the head main body, and a thread portion is formed on the outer periphery of the lower end of the extension rod. It is characterized in that the nut member is detachable.

A fourth aspect of the present invention is characterized in that the head body and the expansion rod in the first aspect of the present invention cannot rotate relative to each other.

According to a fifth aspect of the present invention, there is provided a return spring for constantly applying a biasing force in a contracting direction toward the axis of the head body to each of the grinding wheel shoes according to the first aspect of the present invention. It is characterized by doing.

According to a sixth aspect of the present invention, in the invention of any one of the first to fourth aspects, each of the grinding wheel shoes is replaced with the return spring according to the fifth aspect in accordance with the sliding displacement of the extension rod. A whetstone that has a cam-type whetstone shoe return mechanism that forcibly pulls back in the contraction direction, and presses the whetstone shoes against the tapered cone portion of the expansion rod from a direction that forms a predetermined acute angle with respect to the expansion and contraction directions of each whetstone shoe. It is characterized by having a shoe pressing mechanism.

According to a seventh aspect of the present invention, two types of honing stones respectively held by grinding stone shoes are alternately and radially arranged on a hollow cylindrical head main body, and one of the honing stones is provided in the head main body. Inserting an outer extension rod having a taper cone portion in taper contact with a grinding shoe holding a honing grindstone of the type described above, and inside the outer extension rod, a grindstone shoe holding a honing grindstone of the other type and a taper Insert the inner expansion rod with the tapered cone part that comes into contact, and slide the outer expansion rod or inner expansion rod in the axial direction of the head body to expand or contract the honing grindstone corresponding to the expansion rod in the radial direction of the head body. In the so-called double expansion type honing head, the outer A center hole is formed at both upper and lower ends of the tension rod to support the outer extension rod at both ends by center work, and a push rod is detachably attached to an upper end of the outer extension rod to extend the outer extension rod. It is characterized by being connected.

(7) In the invention according to (8),
A screw hole is formed on the inner side of the center hole formed at the upper end of the outer extension rod according to the invention described in the above, and a push rod is connected to the screw hole so as to screw therewith. I have.

According to a ninth aspect of the present invention, the lower end of the outer extension rod according to the seventh or eighth aspect projects from the head main body, and a thread portion is formed on the outer periphery of the lower end of the outer extension rod. And the nut member is detachable.

The invention described in claim 10 is the invention according to claims 7 to 9
A cam-type grindstone shoe return mechanism for forcibly pulling the corresponding grindstone shoe in the contraction direction in accordance with the sliding displacement of the outer extension rod or the inner extension rod according to any one of the inventions described above, for each of the outer extension rod and the inner extension rod. A whetstone shoe pressing mechanism for individually pressing the whetstone shoes against the taper cone portion of the outer expansion rod from a direction forming a predetermined acute angle with respect to the expansion and contraction directions of the respective whetstone shoes corresponding to the outer expansion rod. It is characterized by having.

Therefore, according to the first aspect of the present invention,
Diamond wheel or CBN as honing wheel
For honing head using a grindstone, when the honing head as a whole is subjected to grindstone formation by cylindrical grinding, that is, truing (including dressing), the center of the cylindrical grinding machine is formed using the center holes formed at both ends of the expansion rod. Grinding with both ends supported. This allows
Accumulation of fitting errors of various members as in the past does not affect the truing accuracy.In addition to the cylindrical grinding accuracy itself becoming the truing accuracy, in addition to the part that should be the reference during truing and the Since the extension reference portion for expanding the honing stone matches, the truing accuracy of the honing head using a high-hardness honing stone such as a diamond grinding stone and, consequently, the honing processing accuracy are remarkably improved.

Further, since the push rod is detachably connected to the upper end of the expansion rod, the push rod remains connected during honing, while
At the time of the above truing, the push rod is removed. This ensures the required length of the expansion rod during honing, while shortening the length supported by the center during truing as much as possible, thereby avoiding the influence of bending of the expansion rod on the truing accuracy.

In particular, according to the second aspect of the present invention, since the push rod is screwed to the expansion rod,
The push rod is attached and detached by fastening and releasing the screw connection.

According to the third aspect of the present invention, at the time of truing, an adjusting nut member is screwed into the external thread portion of the lower end of the expansion rod protruding from the head body.
The head body and the expansion rod are relatively moved by the screwing action to adjust the degree of expansion of the honing grindstones and, consequently, the facing dimensions of the honing grindstones facing each other. As a result, the state where each honing stone is expanded to a predetermined size is self-held.

According to the fourth aspect of the invention, the relative rotation between the head body and the extension rod in the axial direction is allowed while the relative rotation between the head body and the expansion rod is prevented, so that the hit state accompanying the relative rotation is achieved. Prevents the truing accuracy from deteriorating due to the change in

According to the fifth aspect of the present invention, since each of the grindstone shoes is urged in the contracting direction by the return spring, the tapered contact between the expansion rod and each of the grindstone shoes can be reliably maintained.

According to the sixth aspect of the present invention, since the cam type grinding wheel shoe return mechanism is provided in place of the return spring, each grinding wheel shoe automatically contracts or expands in accordance with the sliding displacement of the expansion rod. I do. At this time, as long as it is a cam-type grinding wheel shoe return mechanism, a gap in the radial direction of each grinding wheel shoe is unavoidable. Therefore, at the time of truing, each grinding wheel shoe is restrained by the grinding wheel shoe pressing mechanism. The state in which the shoe is kept in close contact with the expansion rod can be maintained by itself.

According to the seventh aspect of the present invention, assuming that a high-hardness honing wheel such as a diamond wheel or a CBN wheel expands or contracts in accordance with the sliding displacement of the outer expansion rod, the high-hardness honing wheel is used. At the time of truing, the same function as the first aspect is obtained.

According to the eighth aspect of the invention, the outer expansion rod has the same function as the second aspect of the invention.

According to the ninth aspect of the present invention, the same function as the third aspect of the present invention can be obtained for the outer extension rod.

According to the tenth aspect, the same function as that of the sixth aspect is obtained for each of the outer extension rod and the inner extension rod.

[0031]

According to the first aspect of the present invention, honing using a center hole provided at both ends of an extension rod is performed in performing truing of a honing head having a plurality of honing stones as a whole by cylindrical grinding. Since the head can be supported at both ends, the center of rotation of the honing head during truing is not affected by the gap between the fitting of multiple members as in the past, and the standard for forming the grinding wheel and the time for expanding the grinding wheel are used. The truing accuracy is improved even with a honing head using a high-hardness grindstone such as a diamond grindstone, and the honing processing accuracy using the honing head is also improved. is there.

Further, since the push rod can be attached to and detached from the extension rod, the length of the extension rod to be supported at both ends can be shortened by removing the push at the time of truing. The truing accuracy can be further improved by avoiding the influence of flexure or the like due to the weight of the truing.

[0033] In particular, as in the second aspect of the present invention, the push rod has a detachable structure with a screw with respect to the expansion rod. The push rod can be easily attached and detached.

According to the third aspect of the present invention, since the nut member can be attached to the external thread of the lower end of the expansion rod, in addition to the same effect as the first or second aspect of the present invention, truing is also possible. Sometimes, the expanded state of each honing stone can be arbitrarily adjusted by adjusting the tightening of the nut member, and there is an effect that the state can be easily held by itself.

According to the fourth aspect of the present invention, since the head body and the expansion rod cannot be rotated relative to each other, in addition to the same effects as those of the first to third aspects, There is an effect that it is possible to prevent a decrease in truing accuracy due to a change in the hit state due to the relative rotation between the two during truing.

According to the fifth aspect of the present invention, since each grinding wheel shoe is constantly urged in the contracting direction by the return spring, the same effects as those of the first to fourth aspects of the present invention are obtained. Furthermore, there is an effect that the close contact between the grinding shoe and the expansion rod can be reliably maintained during truing.

According to the sixth aspect of the present invention, a cam type grinding wheel shoe returning mechanism and a grinding wheel shoe pressing mechanism are provided in place of the return spring.
In addition to the same effects as those of the inventions described in any one of the above-described embodiments, there is an effect that it is possible to avoid the influence on the truing accuracy due to various gaps and rattling despite the absence of the return spring.

According to the seventh aspect of the present invention, a so-called double expansion type honing head has a structure similar to that of the first aspect of the invention, wherein the outer expansion rod arranged on the outside is employed. When truing is performed on the honing stone driven by the expansion rod, the same effect as the first aspect can be obtained.

According to the eighth aspect of the present invention, since the same structure as that of the second aspect of the present invention is employed for the outer extension rod, the same effect as that of the second aspect of the present invention is obtained. Is obtained.

According to the ninth aspect of the present invention, since the same structure as that of the third aspect of the present invention is employed for the outer extension rod, the same effect as that of the third aspect of the present invention is obtained. Is obtained.

According to the tenth aspect of the present invention, the so-called double expansion type honing head of the seventh aspect employs the same structure as that of the sixth aspect of the invention. The same effects as those of the invention described in (1) can be obtained.

[0042]

1 and 2 show a preferred first embodiment of the present invention.
In the drawings showing the embodiment, a honing head 1 is formed mainly of a head main body 4 composed of a hollow cylindrical holder 2 and a joint member 3 attached to one end of the holder 2 (the upper end in the honing processing posture). Have been. A plurality (even number) of grindstone accommodation grooves 5 are radially formed in the holder 2, and a high-hardness honing grindstone 7 made of, for example, a CBN grindstone or the like held individually by a grindstone shoe 6 in each of these grindstone accommodation grooves 5. Are housed so as to face each other.

The head body 4 has two tapered cone portions 8.
The tapered cone portion 8 is in tapered contact with the inner tapered surface 10 of each of the grinding wheel shoes 6.
Each grindstone shoe 6 is surrounded by an annular return spring 11 disposed at two places together with the holder 2, whereby an urging force acts on the grindstone shoes 6 in a direction of constantly pressing against the tapered cone portion 8. I have. A guide member 12 made of cemented carbide is mounted on the outer peripheral surface of the holder 2 at a position near each honing grindstone 7.

Small-diameter shaft portion 1 at one end (upper end) of expansion rod 9
3 extends to the inside of the joint member 3,
The small-diameter shaft portion 14 at the other end (lower end) protrudes from the end of the holder 2, and center holes 15 and 16 are individually formed in the end surfaces of both small-diameter shaft portions 13 and 14. A female thread 17 is formed in the inner part of the center hole 15 on one small diameter shaft part 13 side, and a male screw part 18 is formed on the outer peripheral surface of the other small diameter shaft part 14. The push rod 19 is connected to the external thread portion 20 by screwing. A return spring 24 is disposed between the washer 21 on the joint member 3 side and the washer 23 attached to the small-diameter shaft portion 13 via the snap ring 22, whereby the expansion rod 9 is moved as shown in FIG. It is always biased to the right.

A key 25 is fixed to one tapered cone portion 8 of the expansion rod 9 with a bolt 26, and a key groove 27 is formed at a position corresponding to the key 25 in the holder 2. The engagement between the key 25 and the key groove 27 prevents the relative rotation of the holder 2 and the expansion rod 9 while allowing the axial movement of the holder 2 and the expansion rod 9.

The joint member 3 includes a plurality of pins 2
8 are implanted, and these pins 28 are used when the honing head 1 is mounted on a main shaft of a honing machine (not shown).

Therefore, according to the honing head 1 of the present embodiment, the expansion rod 9 is slid with respect to the head main body 4 so that the tapered cone portion 8 and the tapered surface 10 come into contact with each other. The honing grindstone 7 expands or contracts in the radial direction.

On the other hand, in order to perform truing (including dressing) in order to reshape each honing grindstone 7 of the honing head 1 shown in FIG. 1, a push rod 19 as shown in FIGS. The screw connection is released and removed from the extension rod 9, and an adjust nut 29 prepared in advance is screwed into the thread portion 18 of the small diameter shaft portion 14 of the extension rod 9. And adjust nut 2
When the screw 9 is tightened while being rotated, the expansion rod 9 slides to the left in FIG. 3, whereby the respective grindstone shoes 6 are gradually pushed outward and the respective honing grindstones 7 expand in the radially expanding direction. When the diameter of the imaginary circle formed by the surface of each honing grindstone 7 reaches a predetermined size, the adjusting nut 29 is fixed by tightening the lock screw 30 attached to the adjusting nut 29.
Thereby, the expanded state of each honing stone 1 can be held by itself.

Subsequently, an adapter 31 prepared in advance is attached to the joint member 3 and the honing head 1 is mounted.
Is set on a cylindrical grinder, and both ends are supported by centers 32 and 33 using center holes 15 and 16 at both ends of the extension rod 9. Then, the honing head 1 is subjected to cylindrical grinding by a traverse grinding method using a truing grindstone G also serving as dressing.

At this time, the center holes 1 at both ends of the extension rod 9
By supporting the honing head 1 using both ends 5 and 16, the center of rotation during cylindrical grinding coincides with the center of each tapered cone portion 8, and as a result, the surface of each honing grindstone 7 is shared. Since the imaginary circle becomes concentric with each tapered cone portion 8, the hitting of the honing grindstones 7 to the workpiece during actual honing is improved. In other words, when the honing head 1 is trued, by directly supporting the extension rod 9 at both ends, it is possible to eliminate the influence on the truing accuracy such as the fitting gap of various components as in the related art.

Further, as is apparent from comparison with FIG.
As a result, the dimension between the honing head 1 and the honing head 1 is hardly affected by the deflection of the honing head 1 due to its own weight, which also improves the cylindrical grinding accuracy, that is, the truing accuracy. Moreover, since the diameter of the small-diameter shaft portion 13 is larger than that of FIG. 8, this also increases the rigidity of the expansion rod 9 and contributes to the improvement of cylindrical grinding accuracy.

Further, since the adjusting nut 29 prevents the further expansion or contraction while maintaining the expanded state of each honing grindstone 7, the expanded state of the honing grindstone 7 may change during truing. The key body 25 and the extension rod 9
Since the relative rotation of the expansion rod 9 and the grinding wheel shoe 6 does not change during truing.

FIGS. 4 and 5 show a second embodiment of the present invention. As shown in FIG. 4, instead of the return spring 11 shown in FIG. A whetstone shoe return mechanism 34 for forcibly expanding or contracting the shoe 6 in the radial direction is provided. That is, a pin hole 35 is formed in each grindstone shoe 6 so that the tapered cone portion 8 is parallel to the cam hole 36. The cam pin 36 implanted on the expansion rod 9 side is slidably inserted into the pin hole 35. Such structures are well known.

When the honing head 41 having this structure is applied to the truing form similar to that shown in FIG.
Cone portion 8 and tapered surface 10 on each grinding wheel shoe 6 side
In addition, a gap between the pin hole 35 and the cam pin 36 is unavoidable, and the intended purpose cannot be achieved. Therefore, a grinding wheel shoe pressing mechanism 37 is separately provided.

That is, in order to securely press the tapered cone portion 8 against the tapered surface 10 of the grindstone shoe 6 during truing, as shown in FIGS. The screw holes 38 in the direction forming the acute angle θ are individually formed, a pressing pin 39 is inserted into each screw hole 38, and the pressing pins 3
The pressing screw 40 is tightened from above the screw 9. The tip of each pressing pin 39 is locally cut off so as to be in surface contact with the side surface of the grindstone shoe 6. The whetstone shoe pressing mechanism 37 including the screw hole 38, the pressing pin 39, and the pressing screw 40 is shown in FIG.
As is clear from FIG. 6, one grindstone shoe 6 is provided at two locations in the longitudinal direction of the grindstone.

Therefore, at the time of truing, each of the honing grindstones 7 is adjusted with the adjusting nut 29 similar to that shown in FIG.
After adjusting the expansion state, the pressing screw 40 is tightened to bring the pressing pin 39 into pressure contact with the side surface of each grinding wheel shoe 6. That is, since the pressing pins 39 apply a force for pressing the grindstone shoes 6 to the taper cone portion 8 and a force for pressing the grindstone shoes 6 to the wall surfaces of the grindstone receiving grooves 5, each of the grindstone shoes 6 is provided with the pressing pins 39. Locked with friction between As a result, it is possible to prevent the occurrence of a gap between the tapered cone portion 8 and the tapered surface 10 of each grinding wheel shoe 6 as described above, and it is possible to perform highly accurate truing just as in the case of FIG. .

FIG. 6 shows a third embodiment of the present invention.
While the first and second embodiments are single extension type honing heads, FIG. 1 shows an example of a double extension type honing head 51. The double-extension type honing head 51 performs a honing operation performed by using a high-hardness honing wheel such as a diamond wheel or a CBN wheel, and a precision finishing operation performed by using a honing wheel such as a GC abrasive. Used when performing substantially in one process without replacing the head, a function that allows two types of honing stones to be mounted on the honing head in advance and that these honing stones can be selectively expanded. It has a known structure.

As shown in FIG. 6, the honing head 51
A honing grindstone 44 of high hardness such as a diamond grindstone or a CBN grindstone and a honing grindstone 45 of normal hardness such as a GC grindstone
Are alternately and radially arranged in the circumferential direction with the grindstone shoes 46 or 47, respectively. A tubular outer extension rod 48 is slidably inserted into the head body 42, and an inner extension rod 49 is slidably inserted into the outer extension rod 48, and a tapered cone portion 50 of the outer extension rod 48 is inserted.
Is in taper contact with the grindstone shoe 46 on the high hardness honing grindstone 44 side, while the taper cone portion 52 of the inner extension rod 49 is in tapered contact with the grindstone shoe 47 of the normal hardness honing grindstone 45. Each of the grindstone shoes 46 and 47 is surrounded by an annular return spring 53 disposed at two places together with the holder 43.
As a result, an urging force is applied to each of the grindstone shoes 46 and 47 in a direction of constantly pressing against the tapered cone portions 50 and 52.

The small-diameter shaft portion 54 at one end (upper end) of the outer extension rod 48 extends to the inside of the joint member 55, and the small-diameter shaft portion 56 at the other end (lower end) protrudes from the end of the holder 43. Center holes 57 and 58 are individually formed in the end faces of both small diameter shaft portions 54 and 56. A female screw portion 59 is formed in a deep portion of the center hole 57 on one small diameter shaft portion 54 side, and a male screw portion 60 is formed on the outer peripheral surface of the other small diameter shaft portion 56.
A push rod 61 is connected to the male screw 9 by screwing with a male screw portion 62. A return spring 66 is disposed between the washer 63 on the joint member 55 side and the washer 65 mounted on the small diameter shaft portion 54 via the snap ring 64, and thereby the outer expansion rod 48 is moved as shown in FIG. Is always biased to the right.

On the other hand, the inner extension rod 49 also has a push rod 67 inserted into the push rod 61 on the outer extension rod 48 side, and the holder 4
The outer expansion rod 48 is urged in the same direction as the outer extension rod 48 by a return spring 69 disposed between the spring support 68 and the spring receiver 68 screwed to the end face of the outer extension rod 3.

A plurality of pins 70 are implanted in the joint member 55, and these pins 70 are used when the honing head 51 is mounted on a main shaft of a honing machine (not shown).

Therefore, according to the present embodiment, FIG.
When performing truing on a high-hardness honing grindstone 44 in the same manner as described above, a normal-hardness honing grindstone 45 that is not a truing target is replaced with a grindstone shoe 47.
At the same time, the spring receiver 68, the return spring 69, the inner extension rod 49, and the push rod 61 are removed.

Then, the same adjustment nut 2 as in FIG.
9 is screwed into the male screw portion 60, and the adjusting nut 2 is
9 to adjust the expanded state of the high-hardness honing grindstone 44. Further, the adapter 31 similar to that shown in FIG. 3 is attached to the joint member 55, and the center holes 57, 58 at both ends of the outer expansion rod 48 are mounted. Are supported at both ends of a cylindrical grinding center (not shown), and truing is performed in the same manner as in FIG.

As described above, also in this embodiment, FIG.
The same operation and effect as those of the first embodiment shown in FIGS.

FIG. 7 is a view showing a fourth embodiment of the present invention. This honing head 71 is similar to that shown in FIG. 4 except that the return spring 53 shown in FIG. A mechanism 34 is provided on both the outer extension rod 9 side and the inner extension rod 49 side, and a grinding wheel shoe pressing mechanism 37 similar to that shown in FIGS. 4 and 5 is attached to a grinding wheel shoe 46 for a high-hardness honing grindstone 44. (However, in FIG. 7, the whetstone shoe pressing mechanism 37 has the same structure as that shown in FIGS. 4 and 5, and is not shown).

In this embodiment, the same operation and effect as those of the above-described embodiments can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a honing head according to a first embodiment of the present invention, and is a cross-sectional view taken along line BB of FIG. 2;

FIG. 2 is a sectional view taken along the line AA in FIG. 1;

FIG. 3 is an explanatory sectional view showing a truing state of the honing head shown in FIG. 1;

FIG. 4 is a half sectional view showing a second embodiment of the honing head according to the present invention.

FIG. 5 is a sectional view taken along the line CC of FIG. 4;

FIG. 6 is a sectional view showing a honing head according to a third embodiment of the present invention.

FIG. 7 is a sectional view showing a fourth embodiment of the honing head according to the present invention.

FIG. 8 is an explanatory sectional view showing a truing state of a conventional honing head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Honing head 4 ... Head body 6 ... Wheelstone shoe 7 ... Honing whetstone 8 ... Taper cone part 9 ... Expansion rod 10 ... Taper surface 11 ... Return spring 15,16 ... Center hole 17 ... Female thread part 18 ... Male thread part 19 ... Push rod 20 ... Male thread 24 ... Return spring 25 ... Key 29 ... Adjust nut 34 ... Wheelstone shoe return mechanism 35 ... Pin hole 36 ... Cam pin 37 ... Wheelstone shoe pressing mechanism 38 ... Screw hole 39 ... Pressing pin 40 ... Pressing screw 42 ... Head bodies 44,45 ... Honing grindstones 46,47 ... Wheelstone shoe 48 ... Outer extension rod 49 ... Inner extension rod 50 ... Taper cone part 51 ... Honing head 52 ... Taper cone part 53 ... Return spring 57,58 ... Center hole 61 ... Push Rod 66 ... Rita Horn spring 67 ... Push rod 69 ... Return spring 71 ... Honing head

Claims (10)

[Claims] 1. An expansion rod having a plurality of honing grindstones respectively held by grindstone shoes arranged radially in a hollow cylindrical head body, and having a tapered cone portion in the head body that is in tapered contact with each grindstone shoe. The honing head that expands or contracts each honing stone in the radial direction of the head body by sliding this expansion rod in the axial direction of the head body. A honing head, wherein a center hole for supporting the extension rod at both ends is formed, and a push rod is detachably connected to an upper end of the extension rod to extend the extension rod. 2. A screw hole is formed in a deep portion of a center hole formed at an upper end of the extension rod, and a push rod is connected to the screw hole so as to be screwed. The honing head according to claim 1. 3. The extension rod has a lower end protruding from the head main body, and a thread portion is formed on the outer periphery of the lower end of the extension rod so that a nut member can be attached and detached. The honing head according to claim 1 or 2, wherein 4. The honing head according to claim 1, wherein the head main body and the extension rod cannot be rotated relative to each other. 5. The honing according to claim 1, further comprising a return spring that constantly applies a biasing force in a contracting direction toward the axis of the head body to each of the grinding wheel shoes. head. 6. A cam-type grindstone shoe return mechanism for forcibly pulling each grindstone shoe in a contraction direction in accordance with a slide displacement of an extension rod, instead of the return spring according to claim 5, 5. A whetstone shoe pressing mechanism for pressing the whetstone shoe against the tapered cone portion of the expansion rod from a direction forming a predetermined acute angle with respect to the expansion and contraction directions of each whetstone shoe. The honing head according to 1. 7. Two types of honing stones respectively held by grinding stone shoes are alternately and radially arranged on a hollow cylindrical head body, and either type of honing stone is held in the head main body. An inner extension rod having a tapered cone portion that is in taper contact with the grinding wheel shoe that is being inserted, and an inner taper cone portion that is in tapered contact with the grinding wheel shoe that holds the other type of honing grindstone is inserted into the outer extension rod. In a honing head in which an expansion rod is inserted, and an outer expansion rod or an inner expansion rod is slid in the axial direction of the head main body to expand or contract the honing grindstone corresponding to the expansion rod in the radial direction of the head main body. At the upper and lower ends of the outer extension rod, To form a center hole for both ends supporting the rods, honing head to the upper end of the outer extension rod being characterized in that detachably connecting the push rod to extend the outer extension rod. 8. A screw hole is formed in a deep portion of a center hole formed at an upper end of the outer extension rod, and a push rod is connected to the screw hole so as to screw therewith. The honing head according to claim 7, wherein 9. The lower end of the outer extension rod can project from the head main body, and a thread portion is formed on the outer periphery of the lower end of the outer extension rod so that the nut member can be attached and detached. The honing head according to claim 7 or 8, wherein: 10. A cam-type grindstone shoe return mechanism for forcibly pulling a corresponding grindstone shoe in a contraction direction in accordance with a sliding displacement of an outer extension rod or an inner extension rod is separately provided for each of the outer extension rod and the inner extension rod. And a whetstone shoe pressing mechanism for pressing the whetstone shoe against the taper cone portion of the outer expansion rod from a direction forming a predetermined acute angle with respect to the expansion / contraction direction of each whetstone shoe corresponding to the outer expansion rod. 7. The method according to claim 7, wherein
A honing head according to any one of claims 1 to 9.