JP6841646B2 - Honing processing equipment - Google Patents

Description

The present invention relates to a honing processing apparatus.

Conventionally, a honing processing device for polishing the inner peripheral surface of a hole formed in a work has been known (see, for example, Patent Document 1).

Patent Document 1 describes a tool head in which a plurality of grindstones are mounted so as to be movable in the radial direction and the entire grindstone is rotationally driven in a state where a plurality of grindstones are arranged in the circumferential direction, and a grindstone diameter scaling means for moving each grindstone in the radial direction. The provided configuration is disclosed. The grindstone diameter expansion / contraction means is composed of a tapered extruded portion whose diameter is reduced downward, and when the extruded portion is lowered, the grindstone mounting plate is pushed outward in the radial direction and the diameter of the circumscribed circle of all the grindstones is expanded. It is supposed to be done.

Then, the tool head is inserted into the hole of the work, the grindstone is pushed outward in the radial direction, the tool head is rotated while being pressed against the inner peripheral surface of the hole, and the hole of the work is polished by repeating the ascent and descent of the tool head. can do.

By the way, in general, in a honing machine, the diameter of the circumscribed circle of all the grindstones is different due to the change in the grindstone posture between when the tool head is raised and when the tool head is lowered, and the cutting force may change. ..

Specifically, as shown in FIGS. 5 and 6, an opening hole 121a into which the grindstone 130a is movably fitted in the radial direction is formed in the peripheral wall portion of the tool head 120. The opening hole 121a is slightly larger than the grindstone mounting plate 130 in order to move the grindstone mounting plate 130 smoothly. In addition, in FIG. 5 and FIG. 6, this gap C is emphasized and expressed.

Therefore, when the tool head 120 is lowered, the grindstone 130a is lowered while being pressed against the inner peripheral surface of the hole Wa of the work W, so that the grindstone mounting plate 130 comes into contact with the upper edge of the opening hole 121a and is on the upper side. It will be in a state of being biased to. Then, a gap C is formed between the lower edge portion of the opening hole 121a and the grindstone mounting plate 130, and the grindstone 130a moves radially outward along the tapered portion 127 of the extruded portion 125 (see FIG. 5). ).

On the other hand, when the tool head 120 rises, the grindstone 130a rises while being pressed against the inner peripheral surface of the hole Wa of the work W, so that the grindstone mounting plate 130 comes into contact with the lower edge portion of the opening hole 121a and lowers. It will be in a state of being biased to the side. Then, a gap C is formed between the upper edge portion of the opening hole 121a and the grindstone mounting plate 130, and the grindstone 130a moves inward in the radial direction along the tapered portion 127 of the extruded portion 125 (see FIG. 6). ).

In this way, when the tool head is lowered, the diameter D1 of the circumscribed circle of all the grindstones becomes larger than the diameter of the target finishing dimension, while when the tool head is raised, the diameter of the circumscribed circle of all the grindstones is large. The diameter D2 tends to be smaller than the diameter of the target finishing dimension. Therefore, as shown in FIG. 7, a machining error occurs between when the tool head is raised and when the tool head is lowered. Further, when the tool head is raised, the machining efficiency is lowered, and as a result, the machining time becomes long.

Therefore, in the invention of Patent Document 1, while detecting whether the grindstone is in contact with the work, the hydraulic cylinder or the air cylinder controls the cutting force of the grindstone so as to be constant when the tool holder is raised or lowered. By doing so, the excessive biting of the grindstone into the work is prevented.

Japanese Unexamined Patent Publication No. 5-318308

However, in the conventional configuration in which the hydraulic cylinder and air cylinder are controlled so that the cutting force is constant when the tool holder is raised and lowered, the structure becomes complicated and the number of parts increases. There was a problem that the cost increased.

The present invention has been made in view of this point, and an object of the present invention is a honing process that has a relatively simple structure and can keep the cutting force of the grindstone constant when the honing tool is raised and lowered. To provide the equipment.

The present invention is intended for a honing machine that processes a work by raising and lowering the honing tool having a grindstone while rotating the work, and has taken the following solutions.

That is, in the first invention, the honing tool is
A spindle that is composed of a hollow shaft member and can rotate around a rotating shaft,
A cylindrical head portion provided at the lower end of the main shaft portion and having a plurality of opening holes formed at intervals in the circumferential direction, and a cylindrical head portion.
A grindstone mounting plate on which the grindstone is mounted and fitted in the opening hole of the head portion and slidable in the radial direction.
A rod housed inside the spindle and slidable in the direction of the rotation axis independently of the spindle.
A cone portion provided at the lower end of the rod and pushing the grindstone mounting plate outward in the radial direction so that the diameter of the circumscribed circle of the grindstone increases as it moves downward.
The grindstone mounting plate is arranged so as to face the cone portion with the grindstone mounting plate interposed therebetween, and by moving upward in conjunction with the downward movement of the cone portion, the grindstone mounting plate is placed between the cone portion and the cone portion. It is characterized by having a holding member to be held narrowly.

In the first invention, when the workpiece is machined by repeating ascending and descending while rotating the honing tool, the cone portion is moved downward to push the grindstone mounting plate outward in the radial direction. ing. Then, the holding member moves upward in conjunction with the downward movement of the cone portion, so that the grindstone mounting plate is sandwiched between the cone portion and the holding member.

As a result, the cutting force of the grindstone can be made constant when the honing tool is raised and lowered. Specifically, since the opening hole is slightly larger than the grindstone mounting plate, this gap causes the grindstone mounting plate to be offset downward or upward when the honing tool is raised or lowered. , The diameter of the circumscribed circle of the grindstone may be different, and the cutting force may change.

Therefore, in the present invention, the grindstone mounting plate is sandwiched between the cone portion and the sandwiching member to prevent the grindstone mounting plate from being biased. As a result, the diameter of the circumscribed circle of the grindstone, that is, the cutting force can be made substantially constant between when the honing tool is raised and when the honing tool is lowered, so that it is possible to suppress a difference in finishing dimensions. Further, even when the honing tool is raised, the machining efficiency does not decrease and the machining time can be shortened.

The second invention is the first invention.
The holding member is composed of a cylindrical member that is slidably fitted into the cylinder of the head portion, and a holding side tapered portion that tapers upward is formed on the upper edge portion of the outer peripheral surface of the holding member. Is provided,
The cone portion includes a cone body provided with a cone-side tapered portion that tapers downward, and a piston portion that extends downward from the cone body and is slidably fitted into the cylinder of the holding member. And
The head portion is provided with a lid portion that closes the lower opening of the head portion.
The grindstone mounting plate is provided with a lower tapered portion corresponding to the holding side tapered portion and an upper tapered portion corresponding to the cone side tapered portion.
An incompressible liquid is sealed in the pressure chamber partitioned by the piston portion, the holding member, the head portion, and the lid portion.
The grindstone mounting plate is sandwiched between the cone portion and the sandwiching member by causing the liquid in the pressure chamber to flow and the sandwiching member to be pushed upward as the cone portion moves downward. It is characterized in that it is extruded outward in the radial direction.

In the second invention, the holding member is pushed upward by the liquid in the pressure chamber flowing as the cone portion moves downward, and the grindstone mounting plate is sandwiched between the cone portion and the holding member. ..

With such a configuration, it is not necessary to separately provide a drive mechanism for moving the holding member upward in conjunction with the downward movement of the cone portion, and the cost can be reduced.

The third invention is the second invention.
The inclination angle of the upper taper portion is substantially equal to the inclination angle of the lower taper portion.

In the third invention, since the inclination angles of the upper taper portion and the lower taper portion are substantially equal, a force is evenly applied to the grindstone mounting plate from the cone portion and the holding member, and the grindstone mounting plate is moved outward in the radial direction. Can be extruded smoothly.

According to the present invention, the diameter of the circumscribed circle of the grindstone, that is, the cutting force can be made substantially constant between when the honing tool is raised and when the honing tool is lowered. The processing time can be shortened as well as the processing of.

It is a side view which shows the structure of the honing processing apparatus which concerns on this embodiment. It is a side sectional view which shows the structure of a honing tool. It is a side sectional view which shows the structure of the honing tool during work processing. It is a graph which shows the difference between a processing diameter and a target diameter. It is a side sectional view which shows the position of the grindstone when the tool head which concerns on the prior art is lowered. It is a side sectional view which shows the position of the grindstone when the tool head which concerns on the prior art is raised. It is a graph which shows the difference between the target diameter and the processing diameter in the honing processing apparatus which concerns on the prior art by partially enlarging.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is essentially merely an example and is not intended to limit the present invention, its application or its use.

As shown in FIG. 1, the honing processing device 10 includes a honing tool 20 for polishing the inner peripheral surface of the hole Wa formed in the work W, a tool driving device 40 for driving the honing tool 20, and a tool driving device 40. It is provided with a control device 60 for controlling the operation.

As shown in FIG. 2, the honing tool 20 has a head portion 21, a spindle portion 22, and a rod 23. The spindle portion 22 is made of a hollow shaft member, and extends in the vertical direction with its center aligned with the rotation axis J. The upper end portion of the spindle portion 22 is rotatably supported by the tool driving device 40 around the rotation axis J.

The rod 23 is housed inside the spindle portion 22 with its center aligned with the rotation axis J. The rod 23 is configured to be slidable and rotatable in the rotation axis J direction independently of the spindle portion 22, and can move forward and backward in the vertical direction as the cutting adjustment motor 56, which will be described later, is driven to rotate.

A cylindrical head portion 21 is provided at the lower end of the spindle portion 22. The head portion 21 is integrally formed with the spindle portion 22 in a state where the center thereof coincides with the rotation axis J. The head portion 21 has a cone portion 25, a grindstone mounting plate 30 on which the grindstone 30a is mounted, and a holding member 35 arranged so as to face the cone portion 25 with the grindstone mounting plate 30 interposed therebetween. The details of the head portion 21 will be described later.

As shown in FIG. 1, the tool driving device 40 includes an elevating mechanism 41 for raising and lowering the honing tool 20, a rotating mechanism 50 for rotating the honing tool 20 around a rotation axis J, and a cutting force of the grindstone 30a of the honing tool 20. It has a notch adjusting mechanism 55 for adjusting. The elevating mechanism 41, the rotating mechanism 50, and the notch adjusting mechanism 55 are mounted on the column 11 of the honing processing device 10.

The elevating mechanism 41 raises and lowers the spindle table 42 by rotating a spindle table 42 that rotatably holds the honing tool 20, a guide rail 43 that can slide the spindle table 42 in the vertical direction, and a ball screw (not shown). It has a feed drive motor 44.

The rotation mechanism 50 includes a transmission belt 51 that transmits a rotational force to the honing tool 20, and a rotation drive motor 52 that rotates the honing tool 20 about the rotation axis J via the transmission belt 51.

The cutting adjustment mechanism 55 raises and lowers the rod 23 of the honing tool 20 and adjusts the amount of movement of the cone portion 25 in the vertical direction to adjust the amount of protrusion of the grindstone 30a in the radial direction, that is, the cutting force of the grindstone 30a. It has a notch adjusting motor 56 for adjusting.

The motors mounted on the honing device 10 such as the elevating mechanism 41, the rotating mechanism 50, and the notch adjusting mechanism 55 are comprehensively driven and controlled by the control device 60. For example, the control device 60 is equipped with various control programs such as a machining program that executes a series of polishing processes.

The control device 60 is housed inside the bed 12 of the honing processing device 10. A work mounting table 15 on which the work W is placed is arranged on the bed 12. In the present embodiment, the work W is composed of a cylindrical member, and the inner peripheral surface of the hole Wa of the work W is polished.

As shown in FIG. 2, the holding member 35 is composed of a cylindrical member slidably fitted in the cylinder of the head portion 21. An upper edge portion of the outer peripheral surface of the sandwiching member 35 is provided with a sandwiching side tapered portion 36 that tapers upward. A seal groove 38 is formed on the outer peripheral surface of the sandwiching member 35 over the entire circumference in the circumferential direction. A seal ring 39 is fitted in the seal groove 38, and the seal ring 39 seals the inner peripheral surface of the head portion 21 and the outer peripheral surface of the holding member 35.

The cone portion 25 has a conical cone body 26 with the top facing down. The cone portion 25 is integrally connected to the lower end of the rod 23 and is arranged at the center of the inside of the head portion 21, and slides and rotates together with the rod 23.

The cone body 26 is provided with a cone-side tapered portion 27 that tapers downward. The cone body 26 is integrally formed with a piston portion 28 that extends downward and is slidably fitted in the cylinder of the holding member 35. A seal groove 38 is formed on the outer peripheral surface of the piston portion 28 over the entire circumference in the circumferential direction. A seal ring 39 is fitted in the seal groove 38, and the inner peripheral surface of the holding member 35 and the outer peripheral surface of the piston portion 28 are sealed by the seal ring 39.

A lid portion 24 that closes the lower opening of the head portion 21 is attached to the lower portion of the head portion 21. The lid portion 24 is formed in a stepped shape so that it can be fitted into the cylinder of the head portion 21. A seal groove 38 is formed in the fitting portion of the lid portion 24 over the entire circumference in the circumferential direction. A seal ring 39 is fitted in the seal groove 38, and the inner peripheral surface of the head portion 21 and the fitting portion of the lid portion 24 are sealed by the seal ring 39.

With such a configuration, the pressure chamber S is partitioned by the piston portion 28, the sandwiching member 35, the head portion 21, and the lid portion 24. The pressure chamber S is filled with an incompressible liquid, for example, oil.

A plurality of grindstone mounting plates 30 having a plate shape are radially arranged around the cone portion 25. A plurality of opening holes 21a are formed in the head portion 21 at equal intervals in the circumferential direction, and the grindstone mounting plate 30 is fitted into the opening holes 21a and is slidable in the radial direction.

A grindstone 30a is mounted on the tip of the grindstone mounting plate 30. The grindstone mounting plate 30 is supported by the head portion 21 so as to be slidably displaceable in the radial direction, and is constantly urged by an elastic member such as a rubber ring (not shown) so as to be pulled inward in the radial direction.

At the base end of the grindstone mounting plate 30, an upper tapered portion 31 corresponding to the cone-side tapered portion 27 of the cone main body 26 and a lower tapered portion 32 corresponding to the sandwiching-side tapered portion 36 are provided. The inclination angle of the upper taper portion 31 and the inclination angle of the lower taper portion 32 are formed to be substantially equal. The inclination angle of the upper taper portion 31 and the inclination angle of the lower taper portion 32 may be different.

Here, at the position of the cone portion 25 shown in FIG. 2, the grindstone mounting plate 30 is not pushed out by the cone portion 25, and the grindstone 30a at the tip thereof is retracted to be in a state where polishing is not possible (retracted position). On the other hand, as shown in FIG. 3, when the upper tapered portion 31 of the base end of the grindstone mounting plate 30 comes into contact with the cone-side tapered portion 27, the grindstone 30a at the tip protrudes outward in the radial direction, and the grindstone 30a is in a state where it can be polished. Becomes (use position).

Specifically, in the grindstone mounting plate 30 at the used position, as the cone portion 25 moves downward from the position shown in FIG. 2, the upper tapered portion 31 comes into contact with the cone-side tapered portion 27 and gradually outwards in the radial direction. Extruded. As a result, the locus of the circumscribed circle formed by the outer surface of the grindstone 30a of the grindstone mounting plate 30 expands in the radial direction.

At this time, as the cone portion 25 moves downward, the oil in the pressure chamber S is pushed by the piston portion 28 to flow. That is, the sandwiching member 35 moves upward in conjunction with the downward movement of the cone portion 25. Then, the grindstone mounting plate 30 is sandwiched between the cone portion 25 and the sandwiching member 35, and is pushed out in the radial direction. As a result, the cutting force of the grindstone 30a can be made constant when the honing tool 20 is raised and lowered.

Specifically, since the opening hole 21a is slightly larger than the grindstone mounting plate 30, this gap allows the grindstone mounting plate 30 to be placed on the lower or upper side when the honing tool 20 is raised or lowered. In a state of being closer, the diameter of the circumscribed circle of the grindstone 30a may be different, and the cutting force may change.

Therefore, in the present embodiment, the grindstone mounting plate 30 is sandwiched between the cone portion 25 and the sandwiching member 35 to prevent the grindstone mounting plate 30 from being biased.

As a result, the diameter of the circumscribed circle of the grindstone 30a, that is, the cutting force can be made substantially constant between when the honing tool 20 is raised and when the honing tool 20 is lowered, so that it is possible to suppress a difference in finishing dimensions ( (See FIG. 4). Further, even when the honing tool 20 is raised, the machining efficiency does not decrease, and the machining time can be shortened.

In the present embodiment, when the inner diameter of the holding member 35 is D, the outer diameter of the holding member 35 is set to D · √2. As a result, the amount of downward movement of the cone portion 25 and the amount of upward movement of the sandwiching member 35 become equal.

Specifically, assuming that both the downward movement amount of the cone portion 25 and the upward movement amount of the holding member 35 are H and the outer diameter of the holding member 35 is X, the oil pushed away by the piston portion 28 of the cone portion 25. The amount of is expressed by the following equation (1).

(D / 2) ²・ π ・ H ・ ・ ・ (1)
On the other hand, the amount of oil that moves the holding member 35 upward by the amount H is expressed by the following equation (2).

((X / 2) ^2- (D / 2) ² ) ・ π ・ H ・ ・ ・ (2)
Since the amounts of both oils are equal, the following equation (3) holds.

(D / 2) ²・ π ・ H = ((X / 2) ^2- (D / 2) ² ) ・ π ・ H ・ ・ ・ (3)
Then, when the equation (3) is calculated, the following equation (4) is obtained, and finally the following equation (5) can be obtained.

^{X 2/4 = D 2/} 2 ··· (4)
X = D ・ √2 ・ ・ ・ (5)
From this, it can be seen that when the inner diameter D and the outer diameter of the sandwiching member 35 are D · √2, the amount of downward movement of the cone portion 25 and the amount of upward movement of the sandwiching member 35 are equal.

As described above, the present invention has a relatively simple configuration, and can obtain a highly practical effect that the cutting force of the grindstone can be made constant when the honing tool is raised and lowered. , Extremely useful and highly industrial applicable.

10 Honing tool 20 Honing tool 21 Head part 21a Opening hole 24 Lid part 25 Cone part 26 Cone body 27 Cone side taper part 28 Piston part 30 Whetstone mounting plate 30a Whetstone 31 Upper taper part 32 Lower taper part 35 Holding member 36 Side taper part S pressure chamber W work

Claims (3)

A honing machine that processes a work by raising and lowering it with respect to the work while rotating a honing tool having a grindstone.
The honing tool
A spindle that is composed of a hollow shaft member and can rotate around a rotating shaft,
A cylindrical head portion provided at the lower end of the main shaft portion and having a plurality of opening holes formed at intervals in the circumferential direction, and a cylindrical head portion.
A grindstone mounting plate on which the grindstone is mounted and fitted in the opening hole of the head portion and slidable in the radial direction.
A rod housed inside the spindle and slidable in the direction of the rotation axis independently of the spindle.
A cone portion provided at the lower end of the rod and pushing the grindstone mounting plate outward in the radial direction so that the diameter of the circumscribed circle of the grindstone increases as it moves downward.
The grindstone mounting plate is arranged so as to face the cone portion with the grindstone mounting plate interposed therebetween, and by moving upward in conjunction with the downward movement of the cone portion, the grindstone mounting plate is placed between the cone portion and the cone portion. A honing machine characterized by having a holding member to be held narrowly. In claim 1,
The holding member is composed of a cylindrical member that is slidably fitted into the cylinder of the head portion, and a holding side tapered portion that tapers upward is formed on the upper edge portion of the outer peripheral surface of the holding member. Is provided,
The cone portion includes a cone body provided with a cone-side tapered portion that tapers downward, and a piston portion that extends downward from the cone body and is slidably fitted into the cylinder of the holding member. And
The head portion is provided with a lid portion that closes the lower opening of the head portion.
The grindstone mounting plate is provided with a lower tapered portion corresponding to the holding side tapered portion and an upper tapered portion corresponding to the cone side tapered portion.
An incompressible liquid is sealed in the pressure chamber partitioned by the piston portion, the holding member, the head portion, and the lid portion.
The grindstone mounting plate is sandwiched between the cone portion and the sandwiching member by causing the liquid in the pressure chamber to flow and the sandwiching member to be pushed upward as the cone portion moves downward. A honing machine characterized by being extruded outward in the radial direction. In claim 2,
A honing machine characterized in that the inclination angle of the upper taper portion is substantially equal to the inclination angle of the lower taper portion.

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