JPH0448576B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cylindrical grinder, and particularly to a cylindrical grinder capable of plunge grinding and angular grinding, and equipped with an automatic workpiece feeder that can automatically feed a workpiece. Regarding grinding machines.

[Conventional technology]

In a conventional cylindrical grinding machine, a headstock and a tailstock for holding and rotating a workpiece are fixed on a reciprocating table of the grinding machine, and a grindstone head with a high-speed rotating grindstone is slidably provided on the bed. The cut into the workpiece is made by moving the table toward the workpiece. By the way, for grinding small parts with a short shaft length, a grindstone 5 with a width longer than the processing length of the workpiece W is mainly used as shown in FIG. There are two types of grinding: plunge grinding, which grinds only the outer diameter, and angular grinding, which cuts diagonally to the axis and grinds the outer diameter and end face simultaneously, as shown in Fig. 9. Since the cutting direction of the grindstone is different between plunge grinding and angular grinding, dedicated grinding machines have traditionally been made and used for each. In addition, as an automatic feeding device that automatically attaches and detaches the workpiece to and from the grinding machine, a gate-shaped guide device surrounding the workpiece holding position (spindle tip position) is installed, and the machine is controlled by the manipulator that runs by the guide device. There are known machines in which the workpiece is taken out from a conveyor on the side and fed to the machine, or in which a robot is separately placed in the front of the machine and the workpiece is fed from the conveyor in the front of the machine.

[Problem to be solved by the invention]

The conventional cylindrical grinder described above has a problem in that it is difficult to grind with high precision, for example, with an outer diameter tolerance of about 1 μm. In addition, in conventional cylindrical grinding machines, plunge grinding machines and angular grinding machines are manufactured as separate models with different machine beds, so the user needs to have both models, and the manufacturer Since there were few parts that could be shared by both models, there were problems such as increased manufacturing costs, which were disadvantageous to both users and manufacturers. Furthermore, automatic workpiece feeding devices used in conventional grinding machines are mainly used for large and medium-sized parts with an axial length of at least 100 mm, and are large-scale and expensive.
There was also the problem that it was too expensive and unsuitable for small parts with a shaft length of about 50 mm.

The present invention aims to solve such conventional problems, and enables high-precision grinding, can be used with both plunge grinders and angular grinders, and can feed workpieces automatically. An object of the present invention is to provide a cylindrical grinding machine equipped with an automatic workpiece feeding device having a simple structure.

[Means to solve the problem]

The present invention, which has been made to achieve the above object, includes a bed, a whetstone head having a rotating whetstone fixed on the bed, and a whetstone held on the bed so as to reciprocate in a direction perpendicular to the axis of the whetstone. a table supported on the table; and a headstock mounted on the table for supporting and rotating a workpiece to be ground; swivelable or removable with respect to the table base so that the axis of the headstock supported above can be placed in a position perpendicular to the direction of movement of the table base and at an angle tilted to perform angular grinding; further comprising an automatic workpiece supply device disposed on the bed on the opposite side of the headstock from the grinding wheel head, the automatic workpiece supply device including a supply chute for supplying the workpiece. and a swinging arm that grips a workpiece at a take-out position in the supply chute and transfers the workpiece to a workpiece holding position by the headstock on the table stand at a retracted position. This is a cylindrical grinding machine with the following features.

[Effect]

As described above, in the cylindrical grinding machine of the present invention, the grinding wheel head is fixed, and therefore the grinding wheel rotates in a fixed position, while the workpiece held by the headstock is fed toward the grinding wheel by the movement of the table stand, and the grinding wheel is rotated at a fixed position. It is configured for exercise. The whetstone head is a whetstone that is larger than the workpiece.
a relatively large-capacity electric motor that rotates the grindstone at high speed;
Since it is equipped with a belt, etc., the overall weight is large, and therefore, when a heavy grindstone head is slid on the bed guide surface to feed the cut, it is difficult to improve the accuracy of the feed. In the present invention, since the headstock side, which is lighter than the grindstone head, is moved, the precision of the cutting feed is increased. In addition, the whetstone rotates at high speed (for example, 1700 rpm) and tends to generate rotational vibration, but since the whetstone head is fixed to the bed, using a vibration-absorbing material for the bed will reduce the rotational vibration of the whetstone. vibration can be absorbed, while the spindle that rotates the workpiece has a relatively low speed (for example, 140
~700rpm), and the rotating parts, electric motor, etc. are smaller than the grindstone head, so there is less vibration due to rotation, and there is less negative impact on the structure in which this part is moved. As a result, grinding accuracy is improved.

Furthermore, in the above cylindrical grinding machine, the table that supports the headstock can be rotated or removed from the table base, so it is possible to change the mounting angle of the table to the table base or replace it with another table. The axis of the workpiece held by the headstock held on the table can be made parallel to or inclined to the axis of the grindstone. Plunge grinding is performed when the table table is fed with the grindstone shaft and workpiece parallel to each other, and angular grinding is performed when the table is tilted. Thus, the grinding machine configured as described above can be used for both plunge grinding and angular grinding.

Further, the cylindrical grinding machine according to the present invention is equipped with an automatic workpiece supply device that includes a workpiece supply chute and a swing arm, and according to the automatic workpiece supply device, the workpiece in the supply chute is shaken. The movable arm can grip it, extract it, feed it to the headstock, and hold it in the headstock. Here, the feed chute feeds the workpiece close to the holding position by the headstock, so the workpiece in the feed chute can be fed to the headstock by simple swinging of the swinging arm, automatically feeding the workpiece to the headstock. The device can be made simple and compact. In addition, the workpiece is fed by the swing arm at a retracted position where the table stand on which the headstock is mounted is retreated in the direction away from the grindstone head, so the swing arm does not interfere with the grindstone. This makes it easier to design the swing arm and the gripper provided at its tip for gripping the workpiece.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described as shown in the accompanying drawings. FIG. 1 is a front view showing one embodiment of the cylindrical grinder of the present invention, and FIG. 2 is a plan view thereof, both of which show a state in which plunge grinding is being performed. Third
The figure is a plan view showing angular grinding with the cylindrical grinder in Figure 1, and Figure 4 is A-A in Figure 1.
FIG. In the figure, 1 is the bed of a cylindrical grinder, 2 is a cover, and 3 is a grindstone head. The whetstone head 3 includes a whetstone shaft 4, a whetstone 5, an electric motor 6, etc., and is fixed onto the bed 1 by suitable means such as bolts.

A table 7 is held on the sliding holding surface 1A of the bed 1 so as to be movable in the Y-Y direction (see FIG. 2) perpendicular to the axis XX of the grindstone 5. Further, a drive device (not shown) is connected to the table base 7 for reciprocating the table base 7 in the Y-Y direction. The upper surface of the table stand 7 has a shape shown in FIG. 5, and a table support surface 7A is formed at the left end. On the table support surface 7A, there is a table 9
is held rotatably about a pivot shaft 8.
The table 9 has a planar shape shown in FIG. 6, and has a dovetail 9A formed on its upper surface. A headstock 12 and a tailstock 13 are held facing each other on the dove table 9A and are fixed with bolts 14. The headstock 12 and tailstock 13 can be moved along the dovetail 9A by loosening the bolt 14, and the mounting position can be adjusted. The headstock 12 includes a main spindle 15 and a workpiece holding mechanism 16.
(collection, chuck, etc.), main shaft drive motor 17
The tailstock 13 has a tailstock center 18, a main shaft 15, a holding mechanism 16, and a tailstock center 1.
8 holds the workpiece W. In addition, the headstock 1
If the workpiece W is firmly held by only the tailstock, the tailstock may be omitted.

The table stand 9 has a headstock 12 and a tailstock 1 on it.
3 and the position where the axis of the workpiece W held in the grinding wheel 5 is parallel to the axis X-X of the grindstone 5 (plunge grinding position shown in FIG. 2) and the angle required to perform angular grinding (for example, about 30 degrees) The table fixing plate 20 and fixing bolts 2 can be rotated to an inclined position (angular grinding position shown in FIG. 3).
1, it can be fixed at each position. In the present embodiment, the table 9 can be switched between the plunge grinding position and the angular grinding position by rotating the table 9 around the rotation axis 8. It is also possible to remove the fixation to the table, change the mounting position and angle, and fix it again.Furthermore, a dedicated table for plunge grinding and a dedicated table for angular grinding may be prepared, and the table held on the table base may be fixed. It is also possible to switch between plunge grinding and angular grinding by replacing the grinding wheel.

In FIGS. 1, 2, and 4, an automatic workpiece feeder 30 is placed on the bed 1 on the opposite side of the table 9 from the grindstone head 3. As shown in FIGS. This automatic feeding device 30 includes a feeding chute 31 that continuously supplies unprocessed workpieces, a swinging arm 32 below the feeding chute, and a swinging arm 32 that supports the swinging arm 32 and swings and moves it in the axial direction as described below. It has a drive device 34, a bracket 35 for supporting the drive device 34, and the like. Any feed chute 31 that can feed the workpieces one by one to the lowest take-out position can be used. In this embodiment, it is made in the shape of a gutter to match the shape of the workpiece W, and a shutter 40 is provided near the lower end as schematically shown in FIG. Shutter 40 includes thin partition plates 41 and 42 that go in and out between the first and second pieces and between the second and third pieces from the bottom of the workpiece, and pneumatic pressure that moves the partition plates. It has a cylinder 43. The two partition plates 41 and 42 are connected on the outside of the chute, and are configured such that when one partition plate enters the chute, the other one retreats. With this configuration, the workpieces can be fed one by one to the take-out position at the bottom of the chute. The supply chute 31 is attached to the casing of the drive device 34, and is maintained at a constant position with respect to the swing arm even if the attachment angle of the drive device 34 with respect to the bed 1 is changed as will be described later.

The swinging arm 32 is approximately V-shaped and has grippers 33A and 33B at each tip. The grippers 33A and 33B are each equipped with an actuator such as a pneumatic cylinder, and are capable of gripping and releasing the workpiece W. The swinging arm 32 is arranged so that its center axis of rotation is parallel to the workpiece W held by the headstock 12 and the tailstock 13 (see FIG. 2), and one gripper 33A is connected to the supply chute 31. It is arranged so as to be movable between a position where the workpiece is held at the lowest part of the grinding wheel and a position where the workpiece is held by the headstock and tailstock on the table stand 7 which is at a retreated position away from the grindstone head 3. Therefore, the swing arm 32 can grasp the workpiece in the supply chute 31 and transfer it to the workpiece holding position by the headstock 12 and tailstock 13 on the table stand 7 in the retracted position. It is possible. The other gripper 33B is for removing and discharging the processed workpiece when the swing arm 32 supplies the workpiece from the supply chute 31 between the headstock and the tailstock. A discharge chute 36 and a product receiver 37 are provided below the swing arm 32 to receive the workpiece taken out by the gripper 33B. Note that the gripper 33B is omitted, the discharge chute 36 is extended below the workpiece held by the headstock and the tailstock, and the processed workpiece is directly dropped into the discharge chute 36 and discharged. You can also do this. Furthermore, a conveyor may be used instead of the discharge chute 36.

As the drive device 34, a mechanism capable of imparting movement to the swing arm 32 as described later can be used as appropriate, and the mechanism can be easily designed by those skilled in the art, so a detailed explanation will be omitted. For example, Utsukai Showa 59-
The one disclosed in No. 163429 can be used. Drive device 3
The bracket 35 supporting the main shaft 15 in FIG.
It has a dovetail 35A parallel to the axis of the dovetail 35A, and the mounting position of the drive device can be adjusted along the dovetail 35A. By adjusting the mounting position of the drive device 34, the workpiece holding position by the gripper of the swinging arm can be adjusted. In the case of angular grinding shown in FIG. 3, a bracket 135 is used in place of the bracket 35 shown in FIG. The axis of rotation is made parallel to the axis of the workpiece W held on the headstock and tailstock. At the same time, the discharge chute 36 is also replaced with a discharge chute 136 for angular grinding.

Next, the grinding operation by the cylindrical grinder having the above structure will be explained. When performing plunge grinding, table 9
is fixed to the table stand 7 in the state shown in FIG. When the table stand 7 retreats in the direction away from the grindstone 3 (to the right in Fig. 2) and stops at the retreat position, the workpiece W is supplied and held by the headstock 12 and tailstock 13 (for details, see (described later). The table stand 7 slides on the bed 1 and moves forward toward the grindstone head 3 to cut the workpiece with the grindstone and perform predetermined grinding. When the workpiece enters the final finishing state and the automatic sizing device (not shown) sends a signal that the workpiece has been finished to the machining dimensions, the automatic sizing device retreats to a position where it does not interfere with the loading and unloading of the workpiece, and the table Platform 7 moves back. When the table stand 7 reaches the retracted position, it stops, and there the workpiece is ejected and a new workpiece is installed. With this, one grinding operation is completed.

In the case of angular grinding, the table 9 is fixed to the table base 7 in the state shown in FIG. In this state, as in the case of plunge grinding, the table stand 7 moves forward toward the grindstone head, and angular grinding is performed on the workpiece W. At this time, since the feed direction of the workpiece is perpendicular to the axis XX of the grinding wheel 5, that is, the YY direction, the amount of cut into the cylindrical surface of the workpiece W inclined with respect to this direction is The value is the feed amount multiplied by cos α (α: inclination angle). After finishing the machining, the table stand 7 returns to the retracted position and the workpiece is replaced.

Next, the operation of supplying and discharging the workpiece will be explained. When the machine is grinding or stopped, the automatic feeder 30 is in the initial state shown in FIG. After grinding, table stand 7
When the automatic feeding device 30 is moved backward and stopped at the backward position, the automatic feeding device 30 starts operating based on the signal. Below, the seventh
This will be explained with reference to the figures. In addition, the following items (a) to (g)
correspond to a to g in FIG.

(a) There is one workpiece at the lowest take-out position of the supply chute 31. Grizzper 33A, 33
With B open, the swing arm 32 swings clockwise.

(b) The swing arm 32 stops at the position where one gripper 33A engages with the workpiece W in the chute and the other gripper 33B engages with the workpiece W held by the holding mechanism 16 of the headstock. do.

(c) The swinging arm 32 shifts in the direction of the rotation center axis and in the direction from the tailstock to the headstock (hereinafter, a shift in this direction will be referred to as backward, and a shift in the opposite direction will be referred to as forward), and then the gripper 33A, 33B
closes and grips each workpiece W. At the same time, the grip of the workpiece by the headstock and tailstock is released.

(d) The swinging arm 32 moves forward with the workpiece gripped by the gripper, and the workpiece gripped by the gripper 33B is extracted from the workpiece holding mechanism of the spindle.

(e) The swing arm 32 swings counterclockwise and stops at the position where the workpiece W held by the gripper 33A is held by the headstock and tailstock. On this occasion,
The other gripper 33B is located above the discharge chute 36.

(f) The swinging arm 32 retreats in its axial direction, causing the workpiece held by the gripper 33A to be inserted into the workpiece holding mechanism of the spindle. After the workpiece is held by the headstock and tailstock, both grippers are released. On the other hand, in the supply chute 31, the lower partition plate 41 is retracted, the workpiece in the chute moves downward, and then the upper partition plate 42 is inserted.

(g) The swing arm 32 moves forward in the axial direction with the gripper open. Thereafter, after the table stand 7 moves forward toward the grindstone head for grinding, the swing arm 32 swings clockwise and returns to the state shown in (a).
Also, in the supply chute 31, the lower partition plate 4
1 is inserted between the first and second workpieces from the bottom, and the upper partition plate 42 is retracted to return to the state shown in (a). With this, one cycle of automatic supply and discharge of the workpiece is completed.

〔Effect of the invention〕

As described above, the cylindrical grinder of the present invention enables highly accurate grinding, and can be switched to either plunge grinding or angular grinding with a simple operation. For this reason, compared to the conventional manufacturing and use of dedicated plunge grinding machines and angular grinding machines,
It has a large economic effect and can manufacture high-precision products (processed products). In addition, since it is equipped with an automatic workpiece feeder that automatically feeds workpieces, it is possible to perform automatic operation.Moreover, the structure of the automatic workpiece feeder is simple and compact, so it can be manufactured at low cost. It is possible. Furthermore, since the automatic workpiece supply device is compact, it is possible to install a cover with a simple structure that surrounds the automatic workpiece supply device and the grinding section, and it is possible to prevent deterioration of the working environment due to grinding fluid mist.

[Brief explanation of drawings]

FIG. 1 is a front view of a preferred embodiment of the invention; FIG.
The figures are plan views of the same, and both show the state in which plunge grinding is performed. FIG. 3 is a plan view showing the state in which angular grinding is performed using the grinding machine shown in FIG. , FIG. 6 is a plan view of the table used in the above embodiment, and FIG. 7 is a diagram illustrating the operation of the automatic workpiece feeding device used in the above embodiment.
FIG. 8 is an explanatory diagram of plunge grinding, and FIG. 9 is an explanatory diagram of angular grinding. 1...Bed, 2...Cover, 3...Whetstone head, 4...Whetstone shaft, 5...Whetstone, 7...Table stand, 8...Swivel axis,
9...table, 12...headstock, 13...tailstock, 3
0... Workpiece automatic supply device, 31... Supply chute,
32... Swinging arm, 33A, 33B... Gripper, 34... Drive device, 35... Bracket, W... Workpiece.

Claims (1)

[Claims] 1 A bed, a whetstone head having a rotating whetstone and fixed on the bed, a table stand held on the bed so as to reciprocate in a direction perpendicular to the axis of the whetstone, and a table stand held on the table stand so as to reciprocate in a direction perpendicular to the axis of the whetstone. and a headstock mounted on the table to support and rotate a workpiece to be ground,
The table is mounted on a table base so that the axis of the headstock supporting the table thereon can be placed in a position at right angles to the direction of movement of the table base and in a position inclined at an angle necessary for performing angular grinding. The automatic workpiece feeding device is rotatably or removably held against the workpiece, and further includes an automatic workpiece feeding device disposed on the bed on the opposite side of the headstock from the grinding wheel head, the automatic workpiece feeding device , a supply chute for supplying a workpiece; and a swinging motion for grasping a workpiece at a take-out position in the supply chute and transferring the workpiece to a workpiece holding position by the headstock on the table stand at a retracted position. A cylindrical grinding machine characterized by having an arm.