JPS5940997Y2 - Safety devices on grinding machines - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a safety device for a grinding machine.

First, a conventional grinding machine to which this invention is applied will be explained with reference to FIGS. 1 to 4.

A swinging table 3 is pivotally supported on a swinging shaft 2 which is suspended horizontally on the pace board IK so as to be able to swing in a seesaw manner.

This rocking table 3 is always biased counterclockwise in FIG. 1 by a weight 5 connected to it via a chain 4.

The chain 4 is hung on a sprocket 6 mounted on a rotatable shaft via a bracket (not shown) on the base plate 1rc.

The swing table 3 before operation is brought to a standstill by the front lower surface of the swing table 3 coming into contact with a stopper bin 7 installed on the base board 1.

A grindstone head 8 is placed on the upper surface 3a of the swing table 3 so as to be movable in the front-rear direction (left-right direction in the drawing).

This grindstone head 8 is moved forward via the screw rod 11 by the operation of the cylinder 10 of the cutting device 9.

A grindstone 13 is provided at the front end of the grindstone head 8 and is actively rotated by the drive of a motor 12 on the whetstone head 8 via a transmission mechanism.

The axis C2 of the grindstone 13 is located on a straight line L2 passing through the axis C of the swing shaft 2 and parallel to the upper surface 3a of the swing table 3, as shown in FIG.

A headstock 15 is mounted on the table 14 at the front end of the base board 1.
A tailstock 16 is installed.

A dresser 17 is installed between the circular tables 15 p i 6 so as to be movable in the front-rear direction via a dresser table 18 .

The dresser 11 is actively rotated by a motor 19 attached to a tailstock 16 via a transmission mechanism.

The axial center C3 of the dresser 17 is located on a horizontal straight line L1 passing through the axial center C1 of the swing shaft 2, as shown in FIG.

A workpiece 22 is held above the dresser 11 between the sensors 20 and 21 of the headstock 15 and tailstock 16.
This work 22 is actively rotated via a transmission mechanism by the drive of a motor 23 attached to the headstock 15Vc.

The axial center C4 of the workpiece 22, as shown in FIG.
distance at the outer circumferential end P1-J, and the outer circumferential end p of the workpiece 22 closest to the pivot shaft 2 after polishing from the axis C1 of the pivot shaft 2
It is provided at a position where the distance at 2t is approximately equal.

In addition, in FIG. 3, the reference numeral 24 indicates the outer periphery of the workpiece 22 before grinding.

The cam follower 25 is attached to the shaft 25 at the rear of the mtdJ stand 3.
a (see Fig. 4).

As shown in FIG. 4, the cam follower 25 is guided by coming into contact with a cam surface 28 of a plate-shaped cam 27 rotatably supported by a shaft 26 on the base board 1 below. It has become.

This cam 27 is actively rotated by the drive of a motor 29 on the base board 1.

A tension cylinder 30 is installed between the lower part of the base board 1 and the rear part of the rocking table 3.

This tension cylinder 30 is turned on at the start of grinding, applies a predetermined tensile load to the rocking table 3, brings the cam follower 25 into contact with the cam surface 28 of the cam 27, and
The cam follower 25 expands and contracts to follow the rotation.

Therefore, due to the rotation of the cam 27, the cam follower 25
By being guided, the rocking table 3 is rocked about the rocking shaft 2.

When the above-mentioned grinding machine is started, the tension cylinder 30 is shortened, and the rocking table 3 rotates clockwise in FIG. 1 about the rocking shaft 2 (hereinafter referred to as normal rotation). is separated from the stopper bin 7, and the cam follower 25 comes into contact with the cam surface 28 of the cam 27.

As the cam follower 25 is guided by the rotation of the cam 27, the rocking table 3 rotates normally around the rocking shaft 2, and the grindstone 13 is dressed by the dresser 17 and then grinds the workpiece 22.

Thereafter, the rocking table 3 rotates counterclockwise in FIG. 1 about the rocking shaft 2 (hereinafter referred to as "reversal") and returns to its original state.

When the grinding machine is brought to an emergency stop while the above-mentioned grinding machine is in operation, each motor 12, 19, 23° 29 and the tension cylinder 30 are turned off.

In particular, for example, if the tension cylinder 30 is turned off when the cam 27 rotates to the position shown by the two-dot chain line in FIG. Due to the action of the weight 5, it may be reversed and come into contact with the stopper bin I with an impact, which poses a problem in the safety of the grinding machine.

Therefore, the purpose of this invention is to provide a safety device that can keep the rocking table stationary with the rocking table inverted only at a predetermined angle when the grinding machine is in operation and comes to an emergency stop. The purpose is to improve the safety of the grinding machine.

An embodiment of this invention will be described below with reference to FIGS. 5A and 6.

A locking pin 40 is protruded from the rocking table 3 below the cam follower 25 and parallel to the cam follower 25 .

A groove 42 is formed on the side surface 27a of the cam 2γ, which is substantially the same as the locus drawn by the locking pin 40 on the cam 27 that guides the cam follower 25.

That is, the grooves 42 and 42 are similar in shape to the cam surface 28 of the cam 27.

The distal end portion 41 of the locking pin 40 is loosely inserted into this groove 41 .

The rotation of the cam 27 causes the cam follower 25 to move toward the shaft 25 &
The cam surface 2B of the cam 27 rolls around the cam surface 2B of the cam 27.

Thereby, the locking pin 40 moves along the groove 42 without contacting the inner peripheral wall 43 and outer peripheral wall 44 of the groove 42.

Occasionally, when an emergency stop is applied and the tension cylinder 30 in FIG. 1 is turned off, the rocking table 3 is reversed by the weight 5.

However, immediately after the reversal starts, the locking pin 40 comes into contact with the outer circumferential wall 44 of the groove 42 of the cam 2T, so the rocking table 3 is stopped in a state of being reversed by a predetermined angle.

That is, for example, if the tension cylinder 30 is turned off when the cam 27 rotates to the state shown in FIG. According to the 75 momme example in which the moving table 3 is reversed,
As shown by the solid line, the rocking table 3 is held still with the cam follower 25 slightly floating above the cam surface 28.

That is, in this invention, when the grinding machine is in operation and comes to an emergency stop, the locking pin, which is provided on the rocking table and drives the groove of the cam during operation, comes into contact with the outer peripheral wall of the groove. Therefore, the rocking table can be held still while being inverted by only a predetermined angle, and the safety of the grinding machine can therefore be improved.

[Brief explanation of the drawings] Figure 1 is a schematic right side view of the grinding machine, Figure 2 is a plan view of the same, Figure 3 is an explanatory diagram showing the arrangement relationship between the grinding wheel, dresser, and workpiece, and Figure 4 is Enlarged side views of conventional cams, Figures 5 to 7
The figures show a safety device according to an embodiment of the present invention, in which FIG. 5 is a side view of the cam, FIG. 6 is a sectional view of the same, and FIG. 7 is a side view of the cam during an emergency stop. 1... Base board, 2... Swing axis, 3.
... Rocking table, 8 ... Grinding wheel stand, 13 ...
...Whetstone, 17...Dresser, 22...
・Work, 25...Cam follower 27...
...Cam, 2γa ... Side of cam, 28.
...Cam surface, 30...Tensile cylinder, 4
0: Locking pin, 41: Tip of the locking pin, 42: Groove, 44: Outer peripheral wall of the groove.

Claims (1)

[Scope of utility model registration request] A rocking table is swingably attached to a rocking shaft horizontally suspended on a base board, and a grindstone table, which is provided at the front so that a grindstone rotates actively, is installed on the rocking table so as to be movable in the front and back direction. A dresser and a workpiece are disposed in the front part of the base plate, and a plate-shaped cam is provided at 15 to actively rotate the base plate Kld. A tension cylinder for applying a predetermined tensile load is installed on the rocking table so that the cam follower provided on the stand comes into contact with the cam surface of the cam and is guided, and the cam follower is guided by the cam. In the grinding machine, the rocking table can be rocked to dress the grindstone with the dresser and grind the workpiece with the grindstone. A protruding groove is provided on the side surface of the cam, which is substantially the same as the locus that the locking pin draws on the side surface of the cam when the cam rotates, and the tip of the locking pin is loosely inserted into the groove. A safety device characterized by an access point.