JPH0545383B2 - - Google Patents

Description

Detailed Description of the Invention (Related Technical Field) The present invention relates to a cantilever type surface grinder, particularly a vertical/horizontal axis square table type surface grinder (where the grinding wheel shaft rotates from the horizontal direction to the vertical direction, or the grinding wheel The present invention relates to a grinding device for grinding the end face of a workpiece (with shafts provided vertically and horizontally).

(Prior art) When performing end face grinding with a conventional cantilever type surface grinder (Fig. 8), (1) As shown in Fig. 9, the horizontal grinding wheel head is rotated 90 degrees horizontally, and the manual handle is turned. (change the orientation of the horizontal grinding wheel head relative to the workpiece in the horizontal plane), or (2) rotate the grinding wheel shaft vertically to rotate the grinding wheel head in the horizontal plane. Rotate and grind by applying cutting feed to the table using the manual handle.

(3) One of the following methods has been used: change the direction of the workpiece in the direction in which it can be ground, and grind it using a horizontal shaft or a horizontal grindstone head (resetting the workpiece on the table).

In the case of (1), it is necessary to make a special horizontal grinding wheel head, it is difficult to improve the positioning accuracy at 0° and 90° positions, the rigidity of the grinding wheel head is reduced, and a cup grinding wheel is used. Because of this, it is not possible to make a large depth of cut, resulting in poor grinding efficiency, and it is difficult to dress the grinding wheel.In the case of (1) and (2), a speed reduction device is required because the table is fed by a manual handle, and the grinding condition can be visually checked. There are problems such as the need to work while doing so, which is dangerous.

In the case of (3), centering time is lost due to changing the orientation of the workpiece, and depending on the shape of the workpiece, the orientation cannot be changed, and the work must be done with a larger grinder. There are problems such as things that should not happen.

(Problem to be solved by the invention) In a cantilever type surface grinding machine, the workpiece can be removed without (1) changing the workpiece setup, (2) replacing the grindstone, and (3) manually operating the table feed handle. The purpose is to enable efficient grinding of end faces.

(Solution Means by the Invention) A cantilever type surface grinding machine having a normal hydraulic cylinder type table drive device and an end face grinding feed device for performing end face grinding, and in which the grinding wheel axis of the grinding machine is vertical, the above-mentioned The hydraulic circuit of the hydraulic cylinder type table driving device is provided with a switching valve for switching the circuit to end face grinding, and the end face grinding feed device is provided with a bracket fixed to the lower part of the table and a pair of clamp pads. A hydraulic clamp device for clamping the bracket, a ball screw provided on the hydraulic clamp device, and a device screwed onto the ball screw, both ends of which are supported by bearings of the bed, and arranged along the sliding direction of the table. A screw shaft is provided, a DC servo motor is connected to one end of the screw shaft, and an origin dog is provided on the table to return the table to the origin, and drives the DC servo motor. Accordingly, feed is applied to the table via the bracket.

(Example) The following will explain based on the drawings. The grinding machine of the present invention is a vertical/horizontal axis square table type surface grinding machine of the type in which the grindstone shaft is movable from a horizontal state as shown in FIG. 8 to a vertical position as shown in FIG. In FIG. 1, 1 is a table of a grinding machine. 2 is a bracket fixed to the lower part of the table 1, and 3 is a hydraulic clamp device, which clamps the bracket 2. 4 is a screw shaft, with bearings 5, 5 on both ends.
It is supported by the table 1 and is disposed along the sliding direction of the table 1, and is rotationally driven by a DC servo motor 8 via a coupling 6 and a reduction gear 7 at one end. 30 is the bed, bearings 5, 5
is fixedly supported. A ball screw 9 is screwed onto the screw shaft 4, and the ball screw 9 is moved laterally by driving the screw shaft 4, so that the table 1 integrated with the clamp device 3 can be moved left and right. 2
Reference numeral 1 denotes an origin dog provided at the bottom of the table 1. The origin dog 21 returns the table 1 to its origin by hitting an origin stopper (not shown) provided on the bed 30.

The clamp device will be explained in more detail with reference to FIGS. 2 and 3. 10 is bracket 2
These are a pair of clamp pads that are clamped together. A hydraulic piston 12 is integrated with each clamp pad 10, and the hydraulic piston 12 is operated by pressure oil sent from a hydraulic pipe 15 to a communication hole 13 provided in the clamp device main body 11. In the illustrated example, there are a total of four pairs of hydraulic pistons. Reference numeral 10a denotes a spring receiver that is integral with the clamp pad 10, and is normally urged outward by the spring 14 so that the clamp pad 10 is in an unclamped state. Reference numeral 16 denotes a connecting body that connects the clamp device main body 11 and the ball screw 9.

FIG. 4 shows a clamp piping system diagram to the hydraulic clamp device 3. P is hydraulic pump, T is tank, 1
7 is a check valve, 18 is a relief valve, 19 is an electromagnetic switching valve, 20 is a pressure increase cylinder, A, B are throttle valves, C,
D is a piston.

Normally, throttle valves A and B are closed. If oil leaks from the hydraulic piston synchronous circuit, hydraulic oil is replenished into the circuit, but in this case, when throttle valve A is closed and throttle valve B is opened, pressure oil is released from C of the pressure booster cylinder 20. The pressure in chamber and D chamber is the same. However, since the relationship is such that the cross-sectional area of chamber C>the cross-sectional area of chamber D, the piston in the pressure increase cylinder 20 rises. As a result, hydraulic oil is supplied from the pump P side to the D chamber, so that the inside of the synchronous circuit of the hydraulic piston 12 is maintained at a predetermined pressure state.

FIG. 6 shows a circuit diagram of the hydraulic cylinder type table drive device of the present application. P is a pump, and 22 is a hydraulic cylinder. 25 is a pump P and a hydraulic cylinder 22
A pipe line 26 connects one chamber of the tank T and the other chamber of the hydraulic cylinder 22 . C
is a solenoid valve for driving and stopping the table, which is installed on the pump P side of pipes 25 and 26, and a
is a solenoid valve that switches the table between left and right rows, and is provided on the hydraulic cylinder 22 side of the pipes 25 and 26. Reference numeral b designates a solenoid valve for forming a closed loop between the conduits 25 and 26, and is provided to connect conduit 25 and conduit 26, which connect solenoid valve a and solenoid valve c. Solenoid valve d transfers oil from pump P to tank T
This is a solenoid valve to return the

(Function) (1) In normal grinding work, the hydraulic cylinder 22 is operated by the drive circuit shown in Fig. 6, and the table 1 is
to drive.

(2) Next, when grinding the end face, drive table 1 by the following operation.

As shown in FIG. 5, the grindstone shaft is rotated vertically so that the grindstone head rotates in a horizontal plane.

The table 1 is moved by the hydraulic cylinder 22 to a position where the origin dog 21 hits an origin stopper (not shown) (origin return operation).

A clamp device 3 clamps the bracket 2 on the underside of the table. The clamping device 3 is shown in the hydraulic circuit diagram of the end face grinding device piping shown in Fig. 4 (Fig. 4).
It is clamped by hydraulic pressure as shown in the figure), and when the hydraulic pressure is released, it is unclamped by the spring 14.

Table drive hydraulic cylinder circuit diagram (6th
Open the solenoid valve d in the figure), close the solenoid valve c, and open the solenoid valve d.

The table 1 is moved to a predetermined position by an NC command, and the end face of the workpiece W is ground with the whetstone of the rotating whetstone head R as shown in FIG. The movement of the table 1 is carried out by the end face grinding feed device comprising a DC servo motor 8, a speed reducer 7, a ball screw 9, and the like. Further, the cutting feed is also performed by moving the table 1. (3) After the end face grinding is completed, the clamping device 3 is unclamped.

(4) Close the electromagnetic valve d in FIG. 6, open the same valve c, and close the valve b to restore the state in which the table can be driven by the hydraulic cylinder 22.

(Effects) In addition to the normal table feed, it is equipped with a feed mechanism for end face grinding that connects with a hydraulic clamp only during end face grinding.
In addition, since the grindstone axis is vertical and the grindstone head is rotated in a horizontal plane, it has become possible to perform end face grinding using the rotating grindstone head while the workpiece is mounted on the table. Eventually, it became possible to efficiently grind the end face of a workpiece without changing the workpiece setup, replacing the grindstone, or manually operating the table's cutting feed.

In particular, the feed mechanism for end face grinding can be performed using a hydraulic mechanism using a pair of clamp pads, and the movement is performed by rotating the screw shaft using a hydraulic servo motor.
Furthermore, since precise feeding is possible due to the relationship between the screw shaft and the ball screw, it has become possible to streamline the grinding work and perform highly accurate end face grinding.

[Brief explanation of drawings]

FIG. 1 shows a feed mechanism for end face grinding according to the present invention. FIG. 2 is a detailed view of the section shown by the arrow in FIG. FIG. 3 is a cross-sectional view taken from FIG. Figure 4 is a hydraulic system diagram of the hydraulic clamp device. FIG. 5 is a schematic diagram of a surface grinder equipped with the present invention. FIG. 6 is a circuit diagram of the hydraulic cylinder type table drive device of the present invention. FIG. 7 is a circuit diagram of a conventional hydraulic cylinder type table drive device. FIG. 8 shows the grinding of the upper surface of a workpiece using a conventional surface grinder. FIG. 9 also shows the end face grinding. In the figure; 1...table (of the grinding machine), 2
...Bracket, 3...Hydraulic clamp device, 4...
...screw shaft, 5...bearing, 6...coupling, 7
...Reducer, 8...DC servo motor, 9...Ball screw, 10...Clamp pad, 10a...
Spring receiver, 11... Clamp device body, 12...
Hydraulic piston, 13...Communication hole, 14...Spring,
15... Hydraulic piping, 16... Connecting body, 17... Check valve, 18... Relief valve, 19... Solenoid switching valve, 20... Pressure increase cylinder, 21... Origin dog, 22... Hydraulic pressure Cylinder.

Claims (1)

[Claims] 1 A cantilever type surface grinding machine having a normal hydraulic cylinder type table drive device and an end face grinding feed device for performing end face grinding, and in which the grinding wheel axis of the grinding machine is vertical, the hydraulic cylinder type table drive A switching valve is provided in the hydraulic circuit of the device to switch the circuit to end face grinding, and the end face grinding feed device clamps the bracket with a pair of clamp pads that are fixed to the bottom of the table. A hydraulic clamp device, a ball screw provided on the hydraulic clamp device, and a screw shaft screwed into the ball screw, both ends of which are supported by bearings on the bed, and which is disposed along the sliding direction of the table. , a DC servo motor connected to one end of the screw shaft, and an origin dog provided on the table to return the table to its origin, and the bracket is moved by driving the DC servo motor. 1. An end face grinding device for a workpiece in a cantilever type surface grinding machine, characterized in that feed is applied to the table through the workpiece.