JPH042758Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a device for preventing deflection of a ball screw in a numerical control (hereinafter simply referred to as "NC") machine tool, more specifically, a ball screw mechanism. The deflection of the ball screw caused by the load shift when performing machine work by moving the machining head or work table is skillfully supported by a stay wheel that rises and falls in response to the rotation of the ball screw. Regarding the prevention device, it can be widely used in NC machine tools that perform hole drilling and cutting.

[Conventional technology and problems to be solved]

By rotating the ball screw supported on the main body frame, the nut slider screwed onto the ball screw moves relatively in the axial direction of the screw, and the processing head or work table connected to the nut slider is moved to a predetermined position. Machine tools that perform processing such as drilling and cutting by transporting objects to a certain point have recently become widely used as numerically controlled machine tools such as NC drill machines, NC grinding machines, and NC lathes.

By the way, in such NC machine tools, the workpiece is machined by sliding the machining head (e.g. drill head, wheel head, bit head), or by moving the worktable on which the workpiece is placed towards the machining head. However, in either method, the ball screw tends to bend due to the load deviation caused by the movement of the processing mechanism or workpiece. The problem was pointed out that smooth continuous machining was hindered.

This invention is a conventional method using a ball twist mechanism.
This was done in view of the above-mentioned difficulties with NC machine tools, and even when a biased load is applied to the ball screw,
It is a technical problem to provide a ball prevention device that skillfully supports the ball screw in a proper position and never causes the ball screw to be deflected.

[Means adopted to solve the problem]

The means adopted by the present inventor to solve the above technical problem will be explained with reference to the attached drawings.
It is as follows.

That is, in the present invention, by rotating the ball screw 2 supported on the main body frame 1, the nut slider 3 screwed onto the ball screw moves relatively in the axial direction of the screw, and the nut slider 3 is coupled to the nut slider 3. In a conventionally well-known NC machine tool that transports a machining head 4 or a work table 5 to a predetermined position and performs machining such as drilling or cutting, a side surface of the main body frame 1 facing the ball screw 2 is , a weight lever 6 having a weight swinging section 61 is pivotably supported, and a stay wheel 7 is rotatably mounted on the driven end 62 of the weight lever 6, so that the weight swinging section 61 is pivotably supported. When the stay wheel 7 is oriented in the direction of gravity, the stay wheel 7 is aligned with the ball screw 2.
By adopting a means of supporting the ball screw 2 by digging into the lower side of the ball screw, the deflection of the ball screw 2 is prevented.

[Example and operation of the example device]

Hereinafter, the present invention will be explained in more detail based on embodiments shown in the accompanying drawings. In addition, Fig. 1 is a front view showing an outline of an NC drill machine constructed by applying the present invention, Fig. 2 is an enlarged front view of the main part of the device of this embodiment, and Fig. 3 is a main part of the device of the same embodiment. It is a cross-sectional explanatory view.

In the drawings, the reference numeral 1 indicates a main body frame laid in bed form, and has a track 11 on its side surface on which a head box (to be described later) runs.

What is designated by the reference numeral 2 is a long ball screw rotatably supported on the side surface of the main body frame 1 so as to be parallel to the track section 11, and is connected to the DC motor 2.
1 gives axial rotation motion in the forward and reverse directions.

Reference numeral 3 indicates a nut slider screwed onto the ball screw 2, which is moved forward and backward to the left and right as the ball screw 2 rotates forward and backward.

The reference numeral 4 designates a machining head (drill), which is disposed at the front end of the head box H. The head box H is slidably engaged with the track 11 on the side surface of the main body frame and is coupled to the nut slider 3, so that when the ball screw 2 rotates and the nut slider moves forward and backward, the processing head Headbox H equipped with 4 is just like the main body frame 1.
You will be able to move at the required speed as if you were riding on a bicycle.

What is designated by code 5 is the main body frame 1 above.
The workpiece set on this workbench is placed on the headbox H.
The machining head 4 moves while performing the machining operation.

The above-mentioned mechanism is almost the same as that of the conventionally known NC drill machine.
The biggest feature is that the ball screw 2 can be supported from below by the stay wheel 7 rotatably attached to the driven end 62 of the weight lever 6. A detailed explanation is as follows.

That is, as shown in FIGS. 2 and 3, the weight lever 6 is pivotally supported by a pivot shaft 64 on a bracket 63 fixed to the side surface of the main body frame 1 so as to be swingable. be. The illustrated weight lever 6 has a sector-shaped weight swinging part 61 as a point of effort, and the opposite side as a point of action (driven end) 62, on which a rotating shaft 71 is supported. This is because the foil 7 is attached.

In the device of this embodiment configured as described above, when the ball screw 2 is rotationally driven by the DC motor 21, the nut slider 3 moves forward and backward. As shown in FIG. 2, due to the rotation of the ball screw 2, the stay wheel 7 supporting the ball screw 2 comes off from the ball screw 2 due to frictional resistance. Since the stay wheel 7 located at is again dug into the underside of the ball screw 2 to support it, the ball screw 2 does not bend and cause problems as in conventional NC machine tools.

Although the structure and operation of the device of this embodiment are generally as described above, the present invention is by no means limited to the above-described embodiment, and various modifications can be made within the scope of the "claims for utility model registration."It's hot,
For example, in the above embodiment, the processing head 4
However, the present inventor also planned to adopt a configuration in which the processing head 4 is fixed and the work table 5 is moved toward the processing head 4, and neither method is suitable for the present invention. It must be said that it falls within the technical scope of the invention.

[Effects of this invention]

As explained above using the embodiments, the device of the present invention skillfully utilizes the friction resistance of the ball screw and the gravity directing action of the weight lever to support the ball screw from below. In addition to being able to completely eliminate the problems caused by the deflection of the ball screw that were inevitable with this type of NC machine tool, the structure can be constructed from two simple parts: the weight lever and the stay wheel.
Since it is not expensive and can be produced economically, its practical value must be said to be extremely great.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an outline of an NC drill machine constructed by applying the present invention, Fig. 2 is an enlarged front view of the main parts of the device of this embodiment, and Fig. 3 is a cross-sectional explanation of the main parts of the device of the embodiment. It is a diagram. 1...Body frame, 2...Ball screw, 3...
...Nut slider, 4...Processing head, 5...
Work table, 6... Weight lever, 61... Weight swinging part, 62... Driven end, 7... Stay wheel,
H...Headbox.

Claims (1)

[Claims for Utility Model Registration] By rotating the ball screw 2 supported on the main body frame 1, the nut slider 3 screwed onto the ball screw is relatively moved in the direction of the axis of the screw. The combined processing head 4 or work table 5 is transported to a predetermined position,
In a numerically controlled machine tool that performs processing such as drilling and cutting, a weight lever 6 having a weight swinging portion 61 is pivotably supported on the side surface of the main body frame 1 facing the ball screw 2. At the same time, a stay wheel 7 is rotatably attached to the driven end 62 of the weight lever 6, so that when the weight swinging section 61 is oriented in the direction of gravity, the stay wheel 7 moves toward the ball screw 2.
A device for preventing deflection of a ball screw, characterized in that the device supports the ball screw 2 by digging into the lower side of the ball screw.