JPS6357174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tilting table that maintains a table surface on which an object is mounted in a tilted state.

In a conventionally known tilting table device, a trunnion formed on the lower side of a movable tilting table is rotatably mounted on a fixed base frame, and a fan-shaped worm wheel is integrally attached to the main body of the table. A rotary operating shaft of the worm that engages with the foil is rotatably disposed on the base frame, so that the tilting table can be set to an arbitrary angular position by rotating the worm operating shaft, and then the table is rotated by a clamping means. By tightening the base onto the base, a desired processing or operation can be performed on the workpiece or object to be measured placed on the table.

However, when setting the tilt angle of the table, not only does the tilt rotation driving force for the table load including the table itself vary depending on the weight of the workpiece tightened on the table and the mounting position, but also the tilt rotation driving force for the table load including the table itself varies. However, the driving torque changes due to the movement of the center of gravity of the load. Therefore, in an active drive system for a tilting table that utilizes a mechanical meshing action such as a worm and a wormwheel, the table load is directly received and supported by the worm meshing part, so the rotational torque of the worm shaft is equal to the load. As the size increases, it becomes larger, and not only does it feel heavy when manually operated, but it also causes elastic strain in the worm meshing teeth, causing an error in the inclination angle. Therefore, the accuracy of the tilting angle of the tilting table using the direct drive worm engagement method is determined by the engagement part between the worm and the worm wheel, so changes in the load, such as the generation of cutting force during machining or the direction of the cutting force, can be avoided. The meshing pressure of the worm also changes due to the rotational speed of the worm shaft, and this effect is significant and makes it difficult to perform precise machining operations in continuous cutting operations by controlling the rotational speed of the worm shaft.

The present invention suppresses the engagement pressure generated between the worm wheel and the worm in the conventional tilting table device described above to a certain minute pressure or less, and eliminates the influence of the table load and the elastic strain of the worm based on the load. It not only allows the rotational operation shaft of the worm to be operated extremely easily regardless of the table load, but also has the feature that the accuracy of the tilt angle can be greatly improved.

The illustrated embodiment will be described in detail below.

The drawings show an embodiment showing the main structure of the present invention. Reference numeral 1 denotes a tilting table, which is set at an angle of inclination of α° with respect to a horizontal plane. A fan-shaped worm foil 2 is integrally formed on the lower surface of the tilting table 1 by means such as bolts. tilt table 1
is rotatably supported on a bearing device disposed in the housing of the fixed base 7. In this case, for example, a trunnion support shaft is formed protruding from the front and rear sides of the table body in alignment with the rotation axis center O of the table. However, these can be supported by a bearing device. Worm 3 meshes with worm foil 2,
A worm shaft 4 to which a worm 3 is fixed is supported within a bearing housing of a fixed base 7 so as to be rotatable and movable in the axial direction. A disk 5 for detecting the axial displacement of the worm shaft is fixed to an intermediate position of the worm shaft 4, and a rotary operation handle 6 is attached to the end of the shaft.
Although the worm shaft 4 is illustrated as being operated manually, it is also possible to adopt a drive system using a control motor, if desired, to achieve a drive system based on automatic electrical control in accordance with a predetermined machining sequence.
Reference numeral 8 is a stopper surface for restricting the movement of the disk 5, and serves to restrict the maximum stroke length of the servo control valve, which will be described later, and to prevent damage to the servo control valve. 10 indicates a servo control valve device constituting a hydraulic servo mechanism;
13 designates a hydraulic power cylinder which is controllably actuated by the device. Reference numeral 9 denotes a servo control valve, and a stylus 11 attached to the tip of the control valve constantly contacts the disk 5 on the worm shaft 4 described above and controls the opening and closing of the servo control valve 9 by following its axial displacement. It is something. Reference numeral 12 denotes a hydraulic power source, which is usually configured as a hydraulic pump unit. 21 indicates a discharge storage tank for hydraulic oil. One end of the hydraulic power cylinder 13 is connected to a support shaft mount 1 provided on the fixed base 7.
The other end of the cylinder is an open end on which the piston rod 14 of the hydraulic piston slides in and out, and the outer end of the piston rod 14, which can reciprocate, It is pivotally connected to the lower side of the periphery.

The operation mode of the present invention having the above-described configuration is as follows. Initially, the surface of the tilting table 1 is placed in a horizontal state, and the table is placed on the fixed base 7.
It is assumed that it is fixed to the side via a clamping means. After the desired workpiece is mounted and fixed on the table surface using a jig or the like when the clamp is fixed, the clamping means of the tilting table is released and the tilting table 1 is rotated from its horizontal position by rotating the rotation operation handle 6 as shown in the figure. Consider the case where the tilting table 1 is set at a desired angle α as shown in FIG. When the clamp is released, the worm shaft 4 is in the home position, ie in the neutral position of the servo control valve 9. This means that the tilting table 1 is still locked by the hydraulic power cylinder 13 and the worm shaft 4 is in a position where it is not restricted by the stop surface 8. Therefore, when the rotation operation handle 6 is rotated to rotate the tilting table 1 counterclockwise, the worm 3 moves to the left by engaging with the worm wheel 2, so that the worm 3 is fixedly attached to the worm wheel 2. The disk 5 also moves to the left, and the servo control valve 9 correspondingly deviates from the neutral position and assumes the switching position. At this time, since the worm 3 does not directly rotate the worm wheel 2, the operating force of the operating handle 6 may be small, and the elastic strain generated in the worm 3 and the worm wheel 2 can be ignored. The hydraulic oil passage at this time is formed as follows: hydraulic power source 12 - oil passage 17 - servo control valve 9 - oil passage 19 - right chamber of the hydraulic power cylinder 13, and the other left chamber of the power cylinder 13 is formed as an oil passage. 18-servo control valve 9-return oil passage 20-storage tank 21. Therefore, the tilting table 1 is rotated counterclockwise by the hydraulic driving force of the hydraulic power cylinder 13 from the horizontal position to the illustrated tilted position. When the tilting table 1 starts rotating, the worm wheel 2 also rotates counterclockwise, so that the worm 2 is moved rightward. The speed of this rightward movement is determined by the opening amount of the servo control valve 9, which determines the pressure oil supply speed to the hydraulic power cylinder 13, but this movement speed is determined by the leftward movement due to the rotation of the rotary operation handle 6. If it is greater than the speed, the worm 3 moves to the right. Then, since the opening amount of the servo control valve 9 becomes smaller, the moving speed in the right direction becomes smaller, and at a certain point, the moving speed becomes balanced. On the other hand, if this moving speed is smaller than the moving speed to the left due to the rotation of the rotary operation handle 6, the worm 3 will move further to the left, but since the opening amount of the servo control valve 9 will become even larger, it will move to the right. As before, the speed increases and at a certain point the moving speed balances out. This tilt table 1
It is necessary to reduce the balance position of the worm shaft 4 during the rotation operation, that is, the amount of displacement of the worm shaft 4, in order to prevent the accuracy of the tilt table from decreasing during operation. Needless to say, make it sufficiently large.
This operation mode of causing the hydraulic power cylinder 13 to follow the displacement of the worm shaft 4 continues even when the rotation operation of the rotation operation handle 6 is stopped, and the worm shaft changes immediately after the rotation operation handle 6 is set to the inclination angle α. Move into position. Naturally, in that position, the servo control valve 9 is in the neutral position, so the supply of pressure oil to the hydraulic power cylinder 13 is stopped.
The tilting table 1 is locked by the oil in the sealed cylinder of the hydraulic power cylinder 13, and the tilting angle α is maintained. Then, if necessary, the tilting table may be fixed to the fixed base 7 side by a clamping means.

In this way, the tilting table device according to the present invention has the following features:
It is not possible to easily operate the worm rotation operating shaft for tilting the table regardless of the load acting on the table during the tilting operation, and the only force acting on the worm engagement surface is the force that moves the worm shaft. , it is possible to avoid as much as possible the setting error of the tilt angle due to the elastic strain of the worm, which contributes to improving the operation and tilt accuracy of this type of tilt table.
In addition, since it is the hydraulic power cylinder that directly drives the tilting table, there is no need to particularly consider the strength and rigidity of the worm or worm wheel, and the device can be small. Therefore, the capacity of the motor that drives the worm can also be reduced. Furthermore, even if the hydraulic system should be damaged, the table will maintain its position due to the engagement between the worm and the worm wheel, and will not tilt sharply, making it safe. The table maintenance force in this case is achieved by the stopper surface 8 facing the disk 5 with a small gap.

[Brief explanation of drawings]

The drawings show an embodiment illustrating the main components of the present invention. 1... Inclined table, 2... Worm foil,
3...Worm, 4...Worm shaft, 5...Disk, 6...Rotary operation handle, 9...Servo control valve, 10...Servo control valve device, 12...Hydraulic power source, 13...Hydraulic power cylinder .

Claims (1)

[Claims] 1. A tilting table is tiltably and rotatably supported on a fixed base frame, a worm wheel is integrally formed on the tilting table, and an operating rotation shaft of a worm that meshes with the worm wheel is supported on the base frame. In a tilting table in which the tilt angle of the table can be set, a worm shaft is supported movably in the axial direction, and a hydraulic power cylinder is used to tilt and rotate the tilting table between the tilting table and a fixed base frame. A servo control valve device that is linked and changes the pressure oil supply to the hydraulic power cylinder in response to the axial displacement of the worm shaft, and a pressure oil between the cylinder chamber of the hydraulic power cylinder and the servo control valve device. A movable tilting table characterized in that pressure oil from the servo valve device is supplied to a cylinder chamber that acts in a direction to reduce axial displacement of the worm shaft by providing an oil passage for supply.