JP6827768B2 - Grinder - Google Patents

Description

The present invention relates to a grinding machine for grinding an outer peripheral surface of a work such as a cam provided in an internal combustion engine.

This type of grinding machine includes a pair of workpiece supports. The pair of work supports clamp both ends of the work on the bed and rotate the work around the horizontal axis. The saddle located on the bed moves along the rotation axis of the work, and the rotating grindstone located on the saddle and the grindstone base provided with the driving mechanism thereof move in a direction orthogonal to the moving direction of the saddle. Then, with the rotary grindstone facing a predetermined machining portion of the work due to the movement of the saddle, the grindstone stands approach the rotating work while the rotary grindstone is rotating, so that the machining portion of the work is ground. Be given.

In a grinding machine having such a configuration, a large amount of coolant is always supplied to the grinding part of the workpiece by the rotary grindstone, and the coolant liquid and coolant mist containing the grinding waste are scattered from the grinding part to the periphery of the machine. There is a risk of Therefore, Patent Document 1 describes, for example, an example of a grinding machine that prevents the coolant from scattering.

The grinding machine described in Patent Document 1 covers the entire machine with an entire cover to prevent the coolant liquid and the like from scattering to the outside of the machine. In addition, this grinding machine covers the processing area including the rotary grindstone and the tip of the work support device that clamps the work in the entire cover with a protective cover, and the scattered coolant liquid etc. is covered with the protective cover. It suppresses the adhesion to.

Japanese Patent No. 3923769

By the way, the processing area for accommodating the work in the grinding machine is required to have a wider size. However, if it is simply intended to widen the machining area, it is not easy to secure a wide machining area, for example, the range covered by the protective cover in the entire cover is widened, which leads to an increase in size of the apparatus.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a grinding machine capable of securing a wider machining area of a workpiece while suppressing an increase in size of the apparatus.

A grinding machine that solves the above problems has a partition wall that divides a processed region that is a region where the work is ground by a grindstone and a non-processed region that is a region other than the processed region, and the non-processed portion through a hole in the partition wall. A spindle extending from the region toward the machining region, having a grip portion for gripping the work at an end located in the machining region, and having the grip portion movable through a hole in the partition wall, and the grip portion. A cover that has a tubular shape and passes through the hole, and the tip of the cover located in the processing region is farther from the partition wall than the vicinity position located near the partition wall and the vicinity position. The cover is configured so that the hole can be moved together with the grip portion so as to be able to move between the separated position and the position, and the cover is located in the vicinity of the hole. It is characterized by including a tip of the cover and a dresser for sharpening the grindstone at a position away from the partition wall from the tip of the grip portion.

The size of the machining area in the extending direction of the spindle is usually set to a size that accommodates the work to be machined. Therefore, with such a configuration, the machined area can be retracted in the direction of the non-machined area together with the gripping portion such as the collet chuck to the vicinity position where the tip of the cover is near the partition wall, so that the spindle extends in the extending direction. Most of the width of the processing area can be used as the accommodation space for the work. When sharpening the grindstone, the dresser sharpens the grindstone at a position farther from the partition wall than the tip of the cover when the tip of the cover is located near the tip of the grip portion and the space for sharpening the grindstone. It is also possible to suppress the expansion of the machining area in the extending direction of the spindle separately in order to secure the above. As a result, the size of the machined area in the extending direction of the spindle can be stopped to a size corresponding to the size of the work, taking into consideration the sharpening of the grindstone. Therefore, it is possible to make the processing area compact.

As a preferred configuration, the cover is cylindrical.
According to such a configuration, since the cover is cylindrical, the volume of the cover occupied by the processing area can be minimized.

As a preferred configuration, when the dresser sharpens the grindstone, the tip of the cover is positioned in the vicinity position.
When the dresser sharpens the grindstone, the coolant and polishing debris are scattered. According to the above configuration, since the cover is located near the position where the dresser sharpens the grindstone on the non-processed area side, the tip of the grip portion is also located on the non-processed area side of the position where the dresser sharpens the grindstone. The risk that the cover and grip will be contaminated by the scattering of coolant, sharpening debris, etc. is suppressed.

As a preferred configuration, the cover has a tip hole having a size that exposes the tip of the grip portion at the tip thereof, and air that forms an air seal between the tip hole and the tip of the grip portion is supplied. It is connected to the pipe.

According to such a configuration, air is supplied from the pipe to the cover to form an air seal between the tip hole of the cover and the tip of the grip portion, so that the coolant liquid, polishing debris, etc. in the processing area can be removed from the tip hole. It is possible to suppress the possibility of invading the inside of the cover and causing troubles such as rotation of the spindle.

As a preferable configuration, the position where the dresser sharpens the grindstone is a position away from the partition wall by a length corresponding to the thickness of the grindstone or more than the near position in the extending direction of the spindle.

According to such a configuration, it is possible to suppress contamination due to scattering of the above-mentioned coolant liquid, polishing debris, etc. when sharpening the entire width of the grindstone in the extending direction of the spindle.
As a preferred configuration, a packing that seals between the outer peripheral surface of the cover and the inner surface of the hole and allows the outer peripheral surface of the cover to slide is further provided.

According to such a configuration, the hole of the partition wall and the cover are sealed with packing, so that even if the cover moves through the hole of the partition wall, the coolant liquid, polishing debris, etc. in the processing area will leave the hole. It is suppressed from entering the non-processed area through it.

According to the grinding machine of the present invention, it is possible to secure a wider machining area of the work while suppressing an increase in the size of the apparatus.

The schematic diagram which shows the schematic structure about one Embodiment which embodied a grinding machine. The block diagram which shows the electric structure in the grinding machine of the same embodiment. It is a figure which shows the work holding part of the grinding machine of the same embodiment, (a) is the sectional view which shows the sectional structure of the front surface, (b) is the side view which shows the structure of the right side surface. The explanatory view explaining the operation in the grinding machine of the same embodiment.

Hereinafter, an embodiment in which the grinding machine 10 is embodied will be described.
As shown in FIG. 1, the grinding machine 10 includes a bed 11. The bed 11 includes a pair of holding devices 13 and 14 for holding the work W, a dresser 15 installed side by side with the holding device 13, and a grindstone device 16 for grinding the work W held by the holding devices 13 and 14. Is installed. Further, the grinding machine 10 includes a first compartment structure 21 that partitions the machined region 11A and the non-machined region 11B on the bed 11, and a second compartment structure 22 that partitions the machined region 11A and the non-machined region 11C. Is equipped with. The non-processed regions 11B and 11C are partitioned by the first and second compartmentalized structures 21 and 22 so as to suppress the intrusion of coolant, polishing debris, etc. in the processed region 11A.

The holding device 13 supports the work table 30 so as to be movable on the bed 11 in the Z-axis direction 13Z, which is the extending direction of the main shaft 32, via a guide rail (not shown). The work table 30 is moved in the Z-axis direction 13Z via a ball screw (not shown) by a spindle moving motor 30M such as a servomotor installed on the work table 30. The headstock 31 is fixedly supported on the work table 30. A spindle 32 is rotatably supported on the headstock 31 around a rotation axis L1 extending along the Z-axis direction 13Z. The headstock 31 is driven by a spindle rotation motor 32M to rotate the spindle 32 around the rotation axis L1.

The spindle 32 is provided with a grip portion 33 at the tip end, which is the end on the processing region 11A side. The grip portion 33 inserts the first compartment structure 21 and its tip is arranged in the machined region 11A, while the portion on the spindle 32 side is arranged in the non-machined region 11B rather than the first compartment structure 21. ing. The grip portion 33 rotates around the rotation axis L1 according to the rotation of the spindle 32. Further, a grip portion cover 34, which is a cylindrical cover, is provided on the outer periphery of the grip portion 33. The grip portion cover 34 is arranged so that a part of the tip of the cylinder is closed and covers the periphery of the grip portion 33. The grip portion cover 34 has a base end 35 on the headstock 31 side fixed to a connecting portion 36 on the tip end side of the headstock 31 with airtightness. The grip portion cover 34 penetrates the first section structure 21 and its tip is arranged in the processed region 11A, while the portion on the headstock 31 side is arranged in the non-processed region 11B.

The holding device 14 includes a tailstock 40 on the bed 11. The tailstock 40 is arranged so as to face the headstock 31 so that its position can be adjusted. The tailstock 40 is movably supported by the ram 42 in the Z-axis direction 13Z on an axis parallel to the rotation axis L1 of the main shaft 32. The ram 42 penetrates the second compartment structure 22 and its tip is arranged in the machined region 11A, while the base end on the tailstock 40 side is arranged in the non-machined region 11C. The ram 42 has a center pivot 43 at the tip thereof and coaxially with the rotation axis L1 of the main shaft 32.

The pair of holding devices 13 and 14 have the spindle 32 and the ram 42 facing each other. The collet chuck 332 and the center pivot 43 provided at the opposite ends of the spindle 32 and the ram 42 enable the work W to be gripped and opened. The pair of holding devices 13 and 14 grip the work W by narrowing the distance between the collet chuck 332 and the center pivot 43, and open the work W by widening the distance. The central axis of the collet chuck 332 and the central axis of the center pivot 43 are arranged to face each other on the rotation axis L1. In the present embodiment, the work W is, for example, a camshaft in which a plurality of cams are arranged side by side.

That is, in the spindle 31, the spindle 32 is driven by the spindle rotation motor 32M, and the work W gripped between the spindle 32 and the ram 42 is rotated around the rotation axis L1.
The grindstone device 16 is arranged on the bed 11 and is movable in the Z-axis direction 16Z parallel to the rotation axis L1 of the main shaft 32, and is arranged on the Z-axis movement table 60 in the X-axis direction 16X. It has a movable grindstone stand 61. The Z-axis moving table 60 and the grindstone stand 61 have 16Z and X in the Z-axis direction by the feeding action of a ball screw mechanism portion (not shown) having a ball screw rotated by a motor and a nut portion screwed thereto. It can be moved in each of the axial directions 16X. Specifically, the Z-axis moving table 60 is moved in the Z-axis direction 16Z by driving the grindstone Z moving motor 66 (see FIG. 2), and the grindstone base 61 is driven by the grindstone X moving motor 65 (see FIG. 2). It is moved in the X-axis direction 16X.

The grindstone base 61 is rotatably supported around the grindstone axis L2 parallel to the rotation axis L1 of the work W on a plane parallel to ZX. At the tip of the grindstone shaft 62, a rotary grindstone 63 having grinding surfaces 63a and 63b on the outer periphery centered on the grindstone axis L2 is mounted. The grindstone shaft 62 is driven by a grindstone rotation motor 63M installed on the grindstone base 61 to rotate the rotary grindstone 63 around the grindstone axis L2. The rotary grindstone 63 may be provided with a grindstone cover that exposes only the grinding surfaces 63a and 63b and covers the rear portion (opposite side of the work W in FIG. 1) of the rotary grindstone 63.

The dresser 15 includes a dressing member 52 that dresses the grinding surfaces 63a and 63b of the rotary grindstone 63. The dresser 15 is installed near the holding device 13 at a position that does not interfere with the movement of the holding device 13 in the Z-axis direction 13Z. The dresser 15 includes a spindle 53 that is connected to the dresser motor 15M and rotates around the rotation axis L1. The dress member 52 is attached to the tip of the spindle 53. The dress member 52 has a disk shape and rotates around a rotation axis L3 parallel to the rotation axis L1 at the tip of the spindle 53. As the dress member 52, for example, a rotary dresser in which diamond abrasive grains are embedded is used. The dresser 15 penetrates the first section structure 21, and the dress member 52 side is arranged in the processed area 11A, while the dresser motor 15M side is arranged in the non-processed area 11B.

Next, the electrical configuration of the grinding machine will be described with reference to FIG.
The grinding machine includes a control device 80 that controls the operation of the grinding machine. The control device 80 includes a microcomputer composed of a CPU, a ROM, a RAM, and the like. The control device 80 synchronizes the spindle rotation motor 32M, the grindstone rotation motor 63M, the dresser motor 15M, the spindle movement motor 30M, the grindstone X movement motor 65, and the grindstone Z movement motor 66 so that the desired grinding and dressing can be performed. Drive while.

Subsequently, the structure of the tip portion of the holding device 13 will be described in detail with reference to FIGS. 3A and 3B.
A grip portion 33 is rotatably connected to the tip of the main shaft 32 about the same axis. The grip portion 33 includes a connection shaft 331 connected to the spindle 32 and a collet chuck 332 that grips the work W. The collet chuck 332 is provided with a work support hole 334 in the center of a plurality of gripping pieces 333 arranged around the axis. The work support hole 334 rotates around the rotation axis L1 with the rotation axis L1 as the rotation center while gripping the work W with a force that each of the plurality of grip pieces 333 presses toward the center. The tip of the collet chuck 332 projects toward the machining region 11A by a length L34 from the tip surface 342 with respect to the Z-axis direction 13Z. The length L34 is shorter in the Z-axis direction 13Z than up to the dressing position P3 when the grip portion cover 34 is in the vicinity position P1.

The grip portion cover 34 on the tip end side of the headstock 31 is arranged through the spindle hole 212 as a hole of the partition wall 211 formed through the partition wall 211 of the first section structure 21. Further, the spindle base 31 can move in the Z-axis direction 13Z within a range in which the grip portion cover 34 does not come out of the spindle hole 212.

A packing 70 is provided between the inner circumference of the spindle hole 212 and the outer peripheral surface 341 of the grip portion cover 34. The packing 70 is an endless circumferential ring, and is provided on the inner circumference of the spindle hole 212 so as to be interposed between the inner circumference of the spindle hole 212 and the outer peripheral surface 341 of the grip portion cover 34. When the grip portion cover 34 moves in the Z-axis direction 13Z together with the headstock 31, the outer peripheral surface 341 slides on the inner circumference of the packing 70, and the portion penetrating the main shaft hole 212 moves. That is, the grip portion cover 34 changes between the portion in the machined region 11A and the portion in the non-machined region 11B due to the movement in the Z-axis direction 13Z. The packing 70 ensures a high degree of airtightness between the spindle hole 212 and the grip portion cover 34, respectively. That is, the grip portion cover 34 is partitioned between the portion on the processed region 11A side and the portion on the non-processed region 11B side with high airtightness. As a result, the coolant liquid, sharpening debris, etc. in the processed region 11A are suppressed from entering the non-processed region 11B side through the outer peripheral surface 341 of the grip portion cover 34.

The grip portion cover 34 is provided with a chuck hole 343 on the tip surface 342 that covers a part of the tip. The inner diameter R1 of the chuck hole 343 is larger than the outer diameter R2 of the collet chuck 332. Further, the tip portion of the collet chuck 332 is inserted into the chuck hole 343. An annular gap having an inner diameter of R2 and an outer diameter of R1 is formed between the chuck hole 343 and the collet chuck 332. Therefore, the distance between the gaps in the radial direction is "(outer diameter R2-inner diameter R1) / 2" if the central axis of the chuck hole 343 and the central axis of the collet chuck 332 coincide with each other. By inserting and arranging the collet chuck 332 in the chuck hole 343 of the grip portion cover 34 in this way, an annular gap smaller than the chuck hole 343 is maintained. Therefore, it is difficult for foreign matter in the processing region 11A to enter the grip portion cover 34 through the annular gap.

In the grip portion cover 34, the air supply pipe 71 is connected to the non-processed region 11B. The air supply pipe 71 supplies high-pressure air into the grip portion cover 34. Since the base end 35 of the grip portion cover 34 is airtightly fixed to the connection portion 36 of the headstock 31, the air supplied from the air supply pipe 71 is connected to the chuck hole 343 of the tip surface 342. It is discharged to the processing region 11A through an annular gap between the collet chuck 332 and the collet chuck 332. By ensuring a predetermined passing speed of the annular gap of air discharged to the processing region 11A, an air seal is formed in the annular gap, and the inside of the grip portion cover 34 for coolant liquid, sharpening waste, etc. in the processing region 11A. It is possible to suppress the invasion to. The spindle 32 at the base end in the grip portion cover 34 may hinder the rotation when foreign matter such as coolant or sharpening debris enters the bearing mechanism such as a bearing. According to the present embodiment, since the gap is small and is air-sealed, the intrusion of coolant, polishing debris, etc. into the grip portion cover 34 in the processing region 11A is suppressed. Therefore, the possibility that foreign matter or the like in the processing region 11A hinders the rotation of the spindle 32 is suppressed.

The dresser 15 is arranged through the dresser hole 213 through which the dresser motor 15M is formed through the partition wall 211 of the first section structure 21 via the packing 73. Therefore, in the dresser motor 15M, a portion arranged in the processed region 11A and a portion arranged in the non-processed region 11B are partitioned by the dresser hole 213. The dresser 15 arranges the dress member 52 in the processing region 11A. The dressing member 52 has a dressing portion 54 formed on the outer periphery thereof, and the dressing portion 54 is arranged at the dressing position P3 in the processing region 11A separated from the partition wall 211 by a distance L52. This distance L52 is the distance L33A between the proximity position P1 and the partition wall 211, which is the position where the tip of the collet chuck 332 is arranged in the processing area 11A when the holding device 13 is most retracted to the non-processing area 11B side. Longer distance. That is, when viewed from the non-processed region 11B, the dressing position P3 is ahead of the nearby position P1 in the processed region 11A.

The operation of the grinding machine will be described with reference to FIG.
[Work grip]
The holding device 13 is moved from the processing region 11A to the nearest position P1 which is most retracted in the Z-axis direction 13Z. Then, the work W is sandwiched between the collet chuck 332 of the grip portion 33. Then, with the work W gripped by the gripping portion 33, the holding device 13 is advanced in the Z-axis direction 13Z toward the separation position P2, which is the position where the work W is most advanced to the processing region 11A. The holding device 13 is a position between the near position P1 and the separation position P2, and stops at a position where the opposite end of the work W is pressed by the center pivot 43 of the holding device 14, and the work W is paired. It is supported between the holding devices 13 and 14.

Usually, the size in which the work W is accommodated is defined by the size of the machining area in the extending direction of the spindle 32. Since the processing region 11A can be retracted in the direction of the non-machining region 11B together with the grip portion 33 such as the collet chuck 332, the tip of the grip portion cover 34 can be retracted to the vicinity position P1 near the 211 partition wall. Most of the width of the processing region 11A in the extending direction can be used as the accommodation space for the work W.

That is, although the holding device 13 advances and retreats in the Z-axis direction 13Z, the size of the machining region 11A changes because the main shaft hole 212 of the first compartment structure 21 advances and retreats in the range from the separation position P2 to the vicinity position P1. do not do. The size required for the processing region 11A can be suppressed to a size that can be secured when the grip portion cover 34 of the holding device 13 is at the nearest retracted position P1. As a result, the size of the processing region 11A can be made compact (small size). Further, if the processing area 11A can be made compact, the size of the grinding machine 10 can be maintained or reduced. At this time, if the distance L from the near position P1 to the separation position P2 is set to the minimum length necessary for attaching and detaching the work W, the processing region 11A can be further made compact (miniaturized).

Further, the holding device 13 can retract the grip portion cover 34 to a position where it does not come out of the spindle hole 212. In the present embodiment, even if the grip portion 33 has a structure for advancing and retreating, it is possible to suppress a useless length required for the structure in the Z-axis direction 13Z but which does not contribute to the extension of the advancing / retreating distance to a short length. .. For example, when a part of the holding device 13 advances from the non-processed region 11B to the processed region 11A, if a bellows is used to protect the portion advanced to the processed region 11A from foreign matter, the folds of the bellows are folded when retracted. Since the overlapping distance is required in the Z-axis direction 13Z, it is necessary to expand the processing region 11A by the folded distance.

[Work grinding]
The pair of holding devices 13 and 14 rotatably hold the work W in the machining region 11A around the rotation axis L1. The pair of holding devices 13 and 14 hold the work W closer to the ram 42 than the dressing portion 54 of the dresser 15. When the work W is arranged in the machining area 11A, the grindstone device 16 moves the rotary grindstone 63 from the standby position (for example, the position shown in FIG. 1) to the machining position. Subsequently, the grindstone device 16 moves in the Z-axis direction 16Z and moves in the X-axis direction 16X so that the grinding surfaces 63a and 63b of the rotary grindstone 63 can be brought into contact with the grinding target portion of the work W. Will be done. The grindstone device 16 is sequentially moved to the machining target portion in the work W by the combination of the movement in the Z-axis direction 16Z and the movement in the X-axis direction 16X, and the rotary grindstone 63 is arranged at an appropriate position for grinding. Will be done. When the grinding of the work W is completed, the grindstone device 16 separates the rotary grindstone 63 from the work W by a combination of movement in the Z-axis direction 16Z and movement in the X-axis direction 16X, and returns the rotary grindstone 63 to the standby position.

When the work W is ground by the rotary grindstone 63, the coolant liquid is scattered in the processing region 11A, and the shavings and the like of the work W are scattered. The holding device 13 is arranged in the non-machined area 11B partitioned by the first section structure 21 so that the foreign matter in the processed area 11A does not adversely affect the mechanisms of the holding devices 13 and 14. The holding device 14 is arranged in the non-processed region 11C partitioned by the second compartment structure 22. In the holding device 13, a part of the grip portion cover 34 and the collet chuck 332 is arranged in the processing area 11A, and in the holding device 14, a part of the ram 42 is arranged in the processing area 11A. By ensuring high airtightness between the non-processed regions 11B and 11C, invasion of foreign matter into the non-processed regions 11B and 11C in the processed region 11A is suppressed. Therefore, in each of the holding devices 13 and 14, the occurrence of defects due to the intrusion of foreign matter is suppressed.

Further, in the grinding machine 10, since the area required for grinding the work W is secured as the machining area 11A, the work W can be ground, and the work W can be attached to and detached from the pair of holding devices 13 and 14. The space can be set back by the holding device 13 without expanding the machining area 11A. Therefore, the machining area 11A can be made to the minimum necessary size for grinding.

Further, since the collet chuck 332 has a complicated shape, it is not easy to secure airtightness here, but by ensuring airtightness between the grip portion cover 34 provided around the collet chuck 332 and the partition wall 211. , The non-processed area 11B can be isolated from the processed area 11A. Further, an annular gap is secured between the chuck hole 343 of the grip portion cover 34 and the collet chuck 332, and high-pressure air is supplied into the grip portion cover 34 to form an air shield in the annular gap. Therefore, it is possible to prevent foreign matter in the processing region 11A from entering the grip portion cover 34. That is, the inside of the grip portion cover 34 can be isolated from the processing region 11A. Therefore, the possibility that a foreign matter causes a problem in the rotation of the spindle 32 is suppressed.

[dressing]
The holding device 13 is moved from the processing region 11A to the nearest position P1 which is most retracted in the Z-axis direction 13Z. The neighborhood position P1 is a position in the processing region 11A that is closer to the partition wall 211 than the dressing position P3. Then, the dresser motor 15M of the dresser 15 is driven to rotate the dress member 52, and the dress member 52 prepares the dressing of the grinding surfaces 63a and 63b of the rotary grindstone 63 at the dressing portion 54.

The distance L52 of the dressing position P3 from the partition wall 211 is longer than the axial thickness D63 of the ground surfaces 63a and 63b. As a result, the rotary grindstone 63 can dress the entire width of the thickness D63 of the grinding surfaces 63a and 63b with the dresser 15 without contacting the partition wall 211.

The grindstone device 16 moves the rotary grindstone 63 from the standby position (for example, the position shown in FIG. 1) to the machining position. Subsequently, the grindstone device 16 moves in the Z-axis direction 16Z and moves in the X-axis direction 16X so that the grinding surfaces 63a and 63b of the rotary grindstone 63 can be brought into contact with the dressing portion 54. The grindstone device 16 sequentially moves the grinding surfaces 63a and 63b with respect to the dressing portion 54 by the combination of the movement in the Z-axis direction 16Z and the movement in the X-axis direction 16X, and is a position suitable for dressing. The grinding surfaces 63a and 63b are arranged on the surface. When the dressing of the grinding surfaces 63a and 63b is completed, the grindstone device 16 separates the rotary grindstone 63 from the dressing position P3 by the combination of the movement in the Z-axis direction 16Z and the movement in the X-axis direction 16X, and the standby position. Return to.

When the dresser 15 dresses the rotary grindstone 63, foreign matter such as the coolant liquid, the dress member 52, and the sharpening debris of the rotary grindstone 63 is scattered around. In particular, since more foreign matter is scattered in the extending direction of the rotating surface of the dress member 52 and the rotary grindstone 63, the equipment and the like in that direction are most contaminated by the foreign matter. In that respect, in the present embodiment, the position P1 near the grip portion cover 34 is retracted toward the partition wall 211 from the dressing position P3, and the rotation surface of the dress member 52 and the rotary grindstone 63 is extended in the extending direction. not exist. As a result, contamination of the outer peripheral surface 341 of the grip portion cover 34 and the collet chuck 332 of the grip portion 33 due to the coolant liquid or sharpening debris can be suppressed.

Further, even if the grip portion cover 34 has a structure of advancing and retreating from the partition wall 211, if contamination is suppressed, foreign matter generated during dressing enters the non-processed region 11B through the outer peripheral surface 341 of the grip portion cover 34. There is little risk of doing so. Further, if the grip portion cover 34 is retracted to the vicinity position P1 that is maximally drawn into the non-processed region 11B, the outer peripheral surface 341 of the grip portion cover 34 contaminated by the dressing is placed in the non-processed region 11B via the packing 70. You will not be drawn into it further. This also reduces the possibility that foreign matter generated by the dressing will enter the non-processed region 11B.

Further, at the time of dressing, an air seal may be formed in the annular gap at the tip of the grip portion cover 34 by supplying high pressure air into the grip portion cover 34. If an air seal is formed in the annular gap, foreign matter generated by the dressing will enter the grip portion cover 34, and the invading foreign matter will be sandwiched between the bearing 36a of the spindle 32 and the like, which will adversely affect the rotation of the spindle 32. Is prevented.

In the grinding machine 10 of the present embodiment, the size of the machining area 11A in the extending direction of the spindle 32 can be stopped to a size corresponding to the size of the work W in consideration of sharpening the rotary grindstone 63. it can. Therefore, the processing area 11A can be made compact.

As described above, according to the grinding machine of the present embodiment, the effects described below can be obtained.
(1) The size of the machining region 11A in the extending direction of the spindle 32 is usually set to a size that accommodates the work W to be machined. If the configuration is such that the machining region 11A can be retracted in the direction of the non-machining region 11B together with the grip portion 33 such as the collet chuck 332 to the vicinity position P1 where the tip of the grip portion cover 34 is near the partition wall 211, the spindle 32 is extended. The width of the processing region 11A in the current direction can be used as the accommodation space for the work W. Then, when the rotary grindstone 63 is sharpened, the dresser 15 is located at a position farther from the tip of the grip portion cover 34 when the tip of the grip portion cover 34 is located at the vicinity position P1 and the tip of the grip portion 33 and the partition wall 211. Since the rotary grindstone 63 is sharpened, it is possible to suppress the expansion of the machining region 11A in the extending direction of the spindle 32 in order to secure a space for sharpening the rotary grindstone 63. As a result, the size of the processing region 11A in the extending direction of the spindle 32 can be stopped to a size corresponding to the size of the work W, taking into consideration the sharpening of the rotary grindstone 63. Therefore, the processing area 11A can be made compact.

(2) If the grip portion cover 34 is cylindrical, the volume of the grip portion cover 34 occupied by the processing region 11A can be minimized.
(3) While the coolant liquid, polishing debris, etc. are scattered by the dresser 15 sharpening the rotary grindstone 63, the grip portion cover 34 is in the machining region 11A and the non-machining region is larger than the position where the dresser 15 sharpens the rotary grindstone 63. In addition to being in the vicinity position P1 on the 11B side, the tip of the grip portion 33 is also on the non-processed region 11B side of the position where the dresser 15 sharpens the rotary grindstone 63. Therefore, the possibility that the grip portion cover 34 and the grip portion 33 are contaminated by the scattering of the coolant liquid, polishing debris, or the like is suppressed.

(4) The coolant liquid in the processing region 11A is formed by supplying air from the air supply pipe 71 to the grip portion cover 34 to form an air seal between the chuck hole 343 of the grip portion cover 34 and the tip of the grip portion 33. It is possible to suppress the possibility that sharpening debris or the like invades the grip portion cover 34 through the chuck hole 343 and causes troubles in the rotation of the spindle 32 or the like.

(5) The entire width of the rotary grindstone 63 with respect to the extending direction of the spindle 32 can be sharpened with the dresser 15.
(6) Since the spindle hole 212 of the partition wall 211 and the grip portion cover 34 are sealed by the packing 70, the coolant that is in the processing region 11A even if the grip portion cover 34 moves the spindle hole 212 of the partition wall 211. Liquid, sharpening debris, etc. are prevented from entering the non-processed region 11B through the spindle hole 212 of the partition wall 211.

(Other embodiments)
The above embodiment can also be implemented in the following embodiments.
[work]
-In the above embodiment, the case where the work W is a camshaft in which cams are arranged side by side has been illustrated, but the present invention is not limited to this, and the work may be any one that needs to grind the outer peripheral surface.

[Packing]
-In the above embodiment, the case where the processed region 11A and the non-processed region 11B are slidably sealed by the packing 70 has been illustrated, but the sealing between the chuck hole and the outer peripheral surface of the grip portion cover is ensured. If so, it may be sealed with a sealing member other than the packing.

[Dressing position]
In the above embodiment, the case where the distance L52 from the partition wall 211 of the dressing position P3 is thicker than the thickness D63 of the rotary grindstone 63 has been illustrated. However, not limited to this, if the distance from the partition wall is greater than the thickness of the grindstone in the portion other than the dressing position, if the distance is such that the partition wall is retracted at the dressing position and the grindstone can be sharpened at the dressing position. May be short.

[Air supply pipe]
-In the above embodiment, the case where air is supplied from the air supply pipe 71 to the grip portion cover 34 to form an air seal has been illustrated, but the present invention is not limited to this, and if air can be supplied into the grip portion cover, air is used. The supply pipe may be connected anywhere on the grip cover. For example, the air supply pipe may be connected from the headstock side.

[Dressing cover position]
-In the above embodiment, the case where the grip portion cover 34 is arranged at the vicinity position P1 during dressing has been illustrated, but the present invention is not limited to this, and the grip portion cover may be close to the partition wall.

[Grip cover]
-In the above embodiment, the case where the grip portion cover 34 has a cylindrical shape has been illustrated, but the present invention is not limited to this, and the grip portion cover may have a cylindrical shape having a polygonal cross section such as a rectangular cross section.

[Neighborhood position]
-In the above embodiment, the neighborhood position P1 is exemplified in the case where the tip surface 342 of the grip portion cover 34 is in the vicinity of the partition wall 211. However, the present invention is not limited to this, and if the tip of the collet chuck does not reach the dressing position in the Z-axis direction, the near position may include a position where the tip surface of the grip portion cover and the partition wall overlap. Further, the nearby position may be a position closer to the partition wall than the dressing position. Contamination will be reduced if the vicinity position is closer to the partition wall than the dressing position.

10 ... Grinder, 11 ... Bed, 11A ... Machining area, 11B, 11C ... Non-machining area, 13 ... Holding device, 13Z ... Z-axis direction, 14 ... Holding device, 15 ... Dresser, 15M ... Dresser motor, 16 ... Grinding stone Equipment, 16X ... X-axis direction, 16Z ... Z-axis direction, 21 ... 1st compartment structure, 22 ... 2nd compartment structure, 30 ... Worktable, 30M ... Spindle moving motor, 31 ... Spindle, 32 ... Spindle, 32M ... Spindle rotation motor, 33 ... Grip part, 34 ... Grip part cover, 35 ... Base end, 36 ... Connection part, 36a ... Bearing, 40 ... Headstock, 42 ... Ram, 43 ... Center pivot, 52 ... Dress member , 53 ... Spindle, 54 ... Dressing part, 60 ... Z-axis moving table, 61 ... Grinding table, 62 ... Grinding shaft, 63 ... Rotating grindstone, 63a, 63b ... Grinding surface, 63M ... Grinding stone rotating motor, 65 ... Grinding stone X movement Motor, 66 ... Grinding stone Z moving motor, 70 ... Packing, 71 ... Air supply pipe, 73 ... Packing, 80 ... Control device, 211 ... Partition wall, 212 ... Spindle hole, 213 ... Dresser hole, 331 ... Connection shaft, 332 ... Collet chuck, 333 ... gripping piece, 334 ... work support hole, 341 ... outer peripheral surface, 342 ... tip surface, 343 ... chuck hole, W ... work.

Claims (6)

A pair of holding devices for holding the work and
A partition wall in which the workpiece is partitioning the non-processing region which is a region other than that the processing region is a region that is ground by grindstone,
A grip portion provided on one holding device, extending from the non-machined region toward the machined region through a hole in the partition wall, and gripping the work at an end located in the machined region, is provided. With a spindle configured to move through the holes in the compartment wall,
A cover that has a tubular shape that surrounds the grip portion and passes through the hole, and the tip of the cover located in the processing region is located near the partition wall and is closer to the partition than the vicinity position. The cover, which is configured to be movable with the grip portion and the hole so as to be able to move between the separated position which is a position away from the wall.
It is located around the hole and is installed side by side with the one holding device, and is fixed at a position that does not interfere with the movement of the holding device in the extending direction of the main shaft, and the cover is positioned at the vicinity position. A grinding machine including a tip of the cover and a dresser for sharpening the grindstone at a position away from the partition wall from the tip of the grip portion. The grinding machine according to claim 1, wherein the cover is cylindrical. The grinding machine according to claim 1 or 2, wherein the tip of the cover is positioned at the vicinity position when the dresser sharpens the grindstone. The cover has a tip hole having a size that exposes the tip of the grip portion at the tip thereof, and is connected to a pipe to which air is supplied to form an air seal between the tip hole and the tip of the grip portion. The grinding machine according to any one of claims 1 to 3. The position where the dresser sharpens the grindstone is set to the thickness of the grindstone more than the tip of the cover when the cover is located in the vicinity position and the tip of the grip portion in the extending direction of the spindle. The grindstone according to any one of claims 1 to 4, which is a position separated from the partition wall by a corresponding length or more. The grinding machine according to any one of claims 1 to 5, further comprising a packing that seals between the outer peripheral surface of the cover and the inner surface of the hole and the outer peripheral surface of the cover is slidable.