JP2000354964A - Grinding machine with local cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a part requiring a sealing mechanism by narrowing a splashing area of a coolant in a grinder and reduce thermal displacement of a bed. SOLUTION: A grinding wheel G to be rotatively driven is provided on a head end of a projected part 15b of a wheel spindle stock 15 guided and supported in the direction toward a workpiece W and to be reciprocation driven by a feeding motor 16, and a grinding part of the workpiece is cooled by a coolant. A local cover 30 to prevent splashing of the coolant by surrounding the workpiece, the grinding wheel and their support parts is provided on a part on a bed 10, a spindle stock positions a spindle motor on the outside of the local cover and provides a sealing structure 20b at a part passing through the local cover, the wheel spindle stock positions its guide support part and the feed motor on the outside of the local cover and inserts the projected part of the wheel spindle stock inside the local cover through a sliding sealing structure A. It is possible to provide a hole on the wheel spindle stock 15 to pass a part of required working fluid and wiring through it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding machine having a bed provided with a cover for preventing coolant supplied to a grinding portion of a workpiece by a grinding wheel from scattering.

[0002]

2. Description of the Related Art A conventional grinding machine of this type employs an entire cover system for covering the entire device in order to prevent coolant from leaking out of the machine, as disclosed in Japanese Utility Model Publication No. 63-34839, for example. The lower cover for receiving and collecting the coolant flowing downward is formed by a part of the bed. The temperature of the coolant is controlled in order to reduce the thermal displacement of the bed due to the temperature change.

[0003]

In the above-described whole-cover type grinding machine, the entire apparatus including the grinding wheel head and the headstock is exposed to the environment in which the coolant scatters, and the coolant is prevented from entering many parts. The structure becomes complicated because it is necessary to provide a sealing mechanism for performing the sealing. Further, since the coolant flows through the entire bed, the total amount of the coolant is increased and the capacity of the storage tank 35 for storing the coolant is also increased. There is a change, which changes the temperature of the bed, which may cause thermal displacement of the bed and adversely affect the processing accuracy. An object of the present invention is to solve each of these problems.

[0004]

A grinding machine provided with a local cover according to the present invention is provided with a headstock provided with a chuck for mounting a workpiece on a tip of a spindle provided on a bed and rotated by a spindle motor. And a grinding wheel that is guided and supported movably on the bed in a direction toward the workpiece, is reciprocally driven by a feed motor, and is rotatably driven by a grinding wheel motor at a protrusion protruding toward the workpiece. A grinding wheel which is provided with a grinding wheel base and which cools a grinding part of the workpiece by the grinding wheel with a coolant, in which the coolant is prevented from scattering around the workpiece, the grinding wheel and their supporting portions. A local cover is mounted on a portion of the bed, the headstock positions the spindle motor outside the local cover and penetrates the local cover of the headstock. The part to be provided with a seal structure for preventing the coolant from leaking, the grindstone head has its guide support part and a feed motor for reciprocating drive positioned outside the local cover, and the protruding part of the grindstone head is the It is characterized by being inserted into the local cover through a sliding seal structure for preventing leakage of coolant. The local cover is provided on a part of the bed surrounding the workpiece, the grinding wheel and their support parts, the spindle head is provided with a spindle motor, and the wheel head is provided with a guide support and a feed motor for reciprocating drive. Since it is located on the outside, the splash of coolant from the grinding portion, which is limited to the scattered range within the local cover, does not reach the vicinity of the guide motor, the guide support of the wheel head, or the feed motor. Further, since the range of the coolant scattered within the local cover is small, the total amount of the coolant is reduced, and the temperature change of the bed due to the temperature change of the coolant is also reduced.

According to a first aspect of the present invention, as shown in the second aspect of the present invention, a lower cover for fixing a local cover on a bed to receive and collect a coolant that is used and flowing downward, and covers an upper side of the lower cover. It is preferable that the bed be made up of an upper cover, and that the bed support the lower cover at the minimum necessary position to reduce the contact area with the lower cover. In this way, the temperature of the coolant is less likely to be transmitted to the bed, so that the temperature change of the bed due to the temperature change of the coolant is further reduced.

[0006] The first and second aspects of the present invention provide a third aspect.
As shown in (1), it is preferable that holes are formed in the grinding wheel base and the protruding portion protruding therefrom, through which a working fluid and wiring required for the support portion of the grinding wheel and the grinding wheel motor are passed.

According to a fourth aspect of the present invention, there is provided a headstock provided with a chuck for mounting a workpiece at a tip of a spindle provided on a bed and rotated by a spindle motor, and movable on the bed in a direction toward the workpiece. A grindstone table that supports a grinding wheel that is guided and supported by a feed motor, is reciprocally driven by a feed motor, and is rotationally driven by a grinding wheel motor at a protruding portion protruding toward the workpiece; Grinding machine provided with a local cover surrounding the grinding wheel, wherein the supply of the working fluid to the support portion of the grinding wheel and the supply of the electric power to the grinding wheel motor are performed through holes formed in the protruding portion of the grinding wheel head. It is.

[0008]

1 to 3 show one embodiment of a grinding machine with a local cover according to the invention. On the bed 10 of this embodiment, a headstock 20 having a chuck 21 for attaching a workpiece W at the tip thereof, a grinding wheel table 15 having a grinding wheel G for grinding the workpiece W at the tip thereof, and a grinding wheel G A truing device 25 for shaping the workpiece W and a sizing device 26 for measuring the workpiece W are provided. The tip of the headstock 20 including the workpiece W and the tip of the grindstone 15 including the grinding wheel G and the truing device 25 are provided. And a local cover 30 surrounding the sizing device 26 is provided on a part of the bed 10.

As shown in FIG. 1, a headstock 20 mounted on a bed 10 has a horizontal spindle (both not shown) rotated by a spindle motor, and a leading end of the spindle is provided with a bearing 20a. A protruding chuck 21 is provided.
A workpiece W of this embodiment is a crankshaft of a rotary compressor including a shaft Wa and two crankpins Wb, and the shaft Wa is coaxially held by a chuck 21 with a main shaft.

[0010] As shown in Figs.
The headstock 2 is fixed via the fixed base 11 and the intermediate base 12.
The main body 0 is supported on the bed 10 so as to be able to reciprocate in a horizontal X direction perpendicular to the main axis and in a Z direction parallel to the main axis. An intermediate base 12 guided and supported by a fixed base 11 fixed on the bed 10 so as to be able to reciprocate in the Z direction. Ball nut 13 fixed to the lower surface of intermediate base 12 and screwed into ball screw 13
It is reciprocated by a. As shown in FIG. 3, the intermediate base 12 has a substantially U-shaped cross section extending in the X direction, and its upper side is connected by a motor mounting base 12a. A pair of guide grooves 12b formed on both sides of the inner surface of the intermediate base 12.
Is slidably engaged with a pair of rails 15a integrally protruding from both sides of the wheel head 15.
5 is guided and supported by the intermediate base 12 so as to be able to reciprocate in the X direction. The upper and lower sliding surfaces on both sides between the guide groove 12b and the rail 15a are static pressure guiding surfaces to which pressurized lubricating oil is supplied.

As shown mainly in FIGS. 1 and 2, the grindstone base 15 is integrally formed with a protruding portion 15b protruding toward the workpiece W supported by the chuck 21 of the headstock 20. A bearing 15c that rotatably supports a grindstone shaft (not shown) parallel to the Z direction is fixed to a tip of the portion 15b. The grinding wheel G attached to one end of the grinding wheel shaft is covered by a cover 22 except for the side facing the workpiece W, and is driven to rotate by a grinding wheel motor 19 attached to the opposite side of the bearing 15c.

As shown mainly in FIGS. 2 and 3, the grindstone base 15 has a linear motor (feeding) comprising a secondary motor element 16b fixed to the upper surface thereof and a primary motor element 16a fixed to the lower surface of the motor mounting base 12a. Motor) 16
As a result, the intermediate base moves between the forward position (see the solid line) where the grinding wheel G contacts and grinds the workpiece W and the retracted position (see the two-dot chain line Ga) where the grinding wheel G separates from the workpiece W. 12 is reciprocated in the X direction. Primary motor element 1
6a is an electromagnetic coil, the secondary motor element 16b is a magnet plate, and the length in the X direction of the primary motor element 16a is shorter than that of the secondary motor element 16b. In this embodiment, the primary motor element 16a faces the secondary motor element 16b over the entire length in the X direction when the wheel head 15 is in the most advanced position (see the solid line in FIG. 2). Is in the last retracted position (see the two-dot chain line 15d in FIG. 2), a part of the front part of the primary motor element 16a is detached from the secondary motor element 16b.

As shown in FIG. 3, a plurality of holes 17a and 17b penetrating in the longitudinal direction (X direction) are formed in the grindstone table 15. The larger hole 17a is used for passing wiring for supplying power to the grinding wheel motor 19, and the plurality of smaller holes 17b are provided between the bearing surface of the grinding wheel shaft provided with the grinding wheel G and the intermediate base 12 and the grinding wheel head 15. This is a pipeline for supplying the lubricating oil to the static pressure guide surface. The joint 17c for supplying lubricating oil to the hole 17b is provided at the rear end of the grindstone table 15.

The truing device 25 installed on the bed 10 moves the grinding wheel base 15 in the X and Z directions to set the grinding wheel G at the position shown by the two-dot chain line Gb. This is for shaping the grinding surface of the grinding wheel G. The sizing device 26 includes a support base 26a installed on the bed 10 and a detection head 26b supported so as to be able to move forward and backward. The outer peripheral surface of the pin portion Wb of the workpiece W ground by the grinding wheel G is formed. It is measured by indirect sizing or post process.

As shown in FIGS. 1 and 2, the local cover 30 includes a lower cover 31 fixed to a part of the bed 10.
The headstock 20 is located inside the local cover 30 only at a portion ahead of the bearing 20a, and the grindstone 15 is located only at a portion ahead of the projection 15b. are doing. The lower cover 31 has an upwardly directed flange portion 31a on four sides and a discharge cylinder portion 3 on the bottom surface.
1b and an opening 31c are formed. The bed 10 is provided with a gap between the bed 10 and the lower cover 31 except for the portion supporting the lower cover 31 and the periphery of the opening 31c, thereby minimizing the heat transfer between the bed 10 and the lower cover 31. Opening 31c
Truing device 25 and sizing device 26
It is for mounting directly on top. Lower cover 31
The cooling pipe cools the grinding section and receives and collects the coolant flowing downward. A guide gutter 34 for guiding the coolant discharged from the discharge cylinder section 31b to the storage tank 35 is attached below the cooling section.

The upper cover 32 is for preventing the coolant supplied to the grinding portion from splashing outside, and the lower edge thereof has a flange portion 31 around the lower cover 31 at four sides.
It is fitted inside a. The headstock 20 is configured such that a spindle motor portion for rotating and driving the spindle is located outside the local cover 30, and a portion ahead of the bearing 20 a is inserted into the local cover 30 through an opening provided in the upper cover 32, and the upper cover 3
A seal structure 20b is provided in a portion penetrating through 2 to prevent coolant leakage.

As shown in FIGS. 1 and 2, the projecting portion 15b of the grindstone table 15 which reciprocates in the X direction is connected to a flange member 18b fixed to the local cover 30 of the intermediate base 12 via a plate member 18a. A horizontally long rectangular plate-shaped slide cover 33 perpendicular to the axis is fixed to the flange member 18b so as to penetrate densely and slidably. On the rear surface of the local cover 30 on the intermediate base 12 side, a rectangular opening 30a smaller than the slide cover 33 but having a length that allows the flange member 18b to reciprocate in the Z direction reciprocation of the intermediate base 12 is provided. Is formed. Opening 30a
The lower edge is formed by the upper edge of the flange portion 31a of the lower cover 31, and the rear surface of the upper cover 32 where the upper edge and both side edges of the opening 30a are formed is a slide cover 33 between the inner surface of the flange portion 31a. The gap is provided by the thickness of the plate. The lower edge of the slide cover 33 has a flange portion 31.
a on the inner surface, and the upper edge and both side edges of the upper cover 32.
Slidably in contact with the rear surface of the
When it reciprocates in the Z direction together with the wheel base 2 and the wheel head 15, the length is such that the opening 30a is always closed in the entire range of the stroke. These plate member 18a, flange member 18b, opening 30a and slide cover 33
Constitutes a sliding seal structure A for preventing the coolant from leaking from the insertion portion in which the projecting portion 15b of the grinding wheel base 15 is inserted into the local cover 30.

Inside the local cover 30, a hollow column 36 rising from the lower cover 31 is provided for wiring to the truing device 25 and the sizing device 26 and piping for supplying coolant adjusted to the grinding portion. .

In the processing standby state, the grindstone table 15 is at the rearmost position shown by a two-dot chain line 15d in FIG. The control device for controlling the operation of the grinding machine moves the grinding wheel table 15 forward in the X direction by the linear motor 16 from this state, and the outer periphery of one pin Wb of the rotating workpiece W gripped by the tip of the spindle. The grinding wheel G rotating on the surface is brought into contact with the surface, and the grinding wheel base 15 is reciprocated in conjunction with the rotation of the main shaft to perform grinding. After grinding one pin portion Wb by a predetermined amount, the control device
5 is retracted once, the main shaft is stopped at a predetermined angular position,
The detection head 26b of the sizing device 26 is advanced, and the size of the dimension is measured by bringing the tip feeler into contact with the outer peripheral surface of the ground pin portion Wb. Then, the remaining grinding amount is calculated, the grinding is performed again, and the crankpin portion is ground with a predetermined accuracy. Note that the wheel head advance position at this time is stored. Next, the grindstone table 15 is moved in the Z direction together with the intermediate base 12 so that the grinding wheel G is opposed to the other pin portion Wb. Grind the outer peripheral surface of. At this time, the other crankpin portion is ground with a predetermined accuracy by performing the grinding process until the one of the crankpin portions comes to the grindstone position at the time of completion of the grinding. After the processing is completed, the workpiece W is detached from the chuck 21, the unprocessed workpiece W is gripped, and grinding is performed in the same manner as described above. Note that a sizing device may be provided at a position facing each pin in order to realize more accurate processing.
Alternatively, the sizing device may be moved in the Z-axis direction according to the processing location.

To each grinding portion between each pin portion Wb and the grinding wheel G, coolant controlled in temperature is supplied from the hollow column 36 through two pipes introduced into the local cover 30 to perform machining. This prevents the temperature rise of the workpiece W and the grinding wheel G due to the heat generated by the heating. Part of the coolant is scattered into the local cover 30 by the grinding wheel G, and the rest flows down onto the lower cover 31. The relatively large droplets of the scattered droplets are blocked by the upper cover 32 of the local cover 30 and flow down along the inner surface onto the lower cover 31, and the bearing 20 a of the headstock 20 and the protrusion 15 b of the grindstone head 15. Is inserted into the local cover 30 by the seal structure 20b and the sliding seal structure A, so that it does not leak out of the local cover 30. The coolant that has flowed onto the lower cover 31 is discharged from the discharge tube portion 31b, and is guided by the guide gutter 34.
Then, it is returned to the storage tank 35 and stored therein, cooled to a predetermined temperature by a cooler, and supplied to the grinding unit again. Fine droplets floating in the local cover 30 are sucked and collected by a mist collector (both not shown) through a duct.

Each time the machining of a predetermined number of workpieces W is completed,
The grinding wheel base 15 is moved in the X direction and the Z direction to position the grinding wheel G at the position of the two-dot chain line Gb (see FIG. 1), and the truing device 25 is operated to shape the ground surface of the grinding wheel G by the truer 25a.

According to the above-described embodiment, the headstock 20
The spindle motor, the guide support of the wheel head 15 and the feed motor 16 are located outside the local cover 30 so that coolant does not splash. Therefore, coolant does not enter these parts without providing a special seal structure. Therefore, there is no possibility that the structure will be adversely affected, so that the structure of these parts can be simplified. In addition, since the local cover 30 is provided on a part of the bed 10, the total amount of the coolant is smaller than that of the conventional whole cover, and the capacity of the storage tank for storing the coolant is also reduced. Can be

Although the temperature of the coolant supplied to the grinding unit is adjusted, the temperature of the coolant collected in the lower cover 31 varies depending on the operating condition. However, the local cover 30 is provided on a part of the bed 10,
In addition, as described above, the bed 10 has the lower cover 31 except for the portion supporting the lower cover 31 and the periphery of the opening 31c.
The heat transfer between the lower cover 31 and the lower cover 31 is reduced as much as possible, so that the temperature change of the bed 10 due to the temperature change of the coolant is small. Absent.

Further, in this embodiment, the inside of the grinding wheel base 15 including the protruding portion 15b is provided with a hole 17a for passing the power supply wiring to the grinding wheel motor 19, the bearing surface of the grinding wheel shaft, and the static pressure guide surface of the grinding wheel base 15. Since the hole 17b for supplying oil is formed, these wirings and pipes are compacted, and a special sealing structure is not required in a portion where they pass through the local cover.

In this embodiment, the supply of the coolant to the two crankpin portions Wb of the workpiece W as the grinding portion is performed by the discharge nozzles provided at the respective ends of the two pipes passing through the hollow column 36. I have. However, the supply of the coolant may be performed through one of the holes 17b provided in the grindstone table 15. In this case, the coolant discharge nozzle moves together with the bearing portion 15c. One is enough.

[0026]

According to the first aspect of the present invention, since the coolant does not reach the guide motor and the vicinity of the feed motor of the grinding wheel head and the feed motor, these coolants do not need to be provided with a special seal structure. No coolant penetrates into the parts and does not adversely affect the structure, so that the structure can be simplified. In addition, the total amount of coolant is reduced, and the capacity of the storage tank for storing it is also reduced, so that the entire grinding machine can be made compact. improves.

According to the second aspect of the present invention, the change in the temperature of the bed caused by the change in the temperature of the coolant is further reduced.
The thermal displacement of the bed is further reduced, and the processing accuracy is further improved.

According to the third aspect of the present invention, the supply of the working fluid to the support portion of the grinding wheel and the supply of the electric power to the grinding wheel motor can be performed through the holes formed in the protruding portion of the grinding wheel base. The wiring can be compacted and the structure is simplified because a special sealing structure is not required at a portion where the wiring passes through the local cover.

Also, in the invention of claim 4, the same operation and effect as those of the invention of claim 3 can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall plan view of an embodiment of a grinding machine provided with a local cover according to the present invention.

FIG. 2 is a cross-sectional view along the X direction of the embodiment shown in FIG.

FIG. 3 is an enlarged sectional view taken along line 3-3 in FIG. 2;

[Explanation of symbols]

10: bed, 15: grindstone table, 15b: protrusion, 16 ...
Feed motors, 17a, 17b ... holes, 19 ... grinding wheel motors,
20: headstock, 20b: seal structure, 21: chuck,
Reference numeral 30: local cover, 31: lower cover, 32: upper cover, A: sliding seal structure, G: grinding wheel, W: workpiece.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Chisen Kato 1-1-1 Asahi-cho, Kariya-shi, Aichi Pref.

Claims (4)

[Claims] 1. A headstock provided on a bed and provided with a chuck for mounting a workpiece at a tip of a spindle rotated by a spindle motor and guided and supported on the bed so as to be movable in a direction toward the workpiece. A grinding wheel base that supports a grinding wheel that is rotationally driven by a grinding wheel motor at a protruding portion that is reciprocally driven by the feed motor and projects toward the same workpiece, and a grinding section of the workpiece by the grinding wheel. In a grinding machine cooled by a coolant, a local cover that surrounds the workpiece, the grinding wheel, and a supporting portion thereof and that prevents the coolant from scattering is attached to a part of the bed, and the headstock is a spindle motor. A seal structure for preventing the coolant from leaking is provided at a portion of the headstock that penetrates the local cover, and The grindstone head has its guide support and feed motor for reciprocating drive positioned outside the local cover, and the protrusion of the grindstone head is located in the local cover through a sliding seal structure for preventing the coolant from leaking. Grinding machine with local cover, characterized by being inserted. 2. The local cover comprises a lower cover which is fixed on the bed and is used to receive and collect a coolant flowing downward, and an upper cover which covers an upper portion of the lower cover, wherein the bed is at a minimum required position. The grinding machine with a local cover according to claim 1, wherein the lower cover is supported to reduce the contact area with the lower cover. 3. The grinding wheel base and a protruding portion protruding therefrom are formed with holes for passing a working fluid and wiring required for the support portion of the grinding wheel and the grinding wheel motor. A grinder provided with a local cover according to item 1. 4. A headstock provided on a bed and provided with a chuck for attaching a workpiece to a tip of a spindle which is driven to rotate by a spindle motor, and is guided and supported on the bed so as to be movable in a direction toward the workpiece. A grindstone table that supports a grinding wheel that is reciprocally driven by a feed motor and that is rotationally driven by a grinding wheel motor at a protruding portion protruding toward the workpiece; and a local area surrounding the workpiece, the grinding wheel, and these supporting portions. In a grinding machine having a local cover having a cover, the supply of working fluid to the support of the grinding wheel and the supply of power to the grinding wheel motor are performed through holes formed in the protrusions of the grinding wheel head. How to supply.