JPH0343164A - vibrating drill - Google Patents

Abstract

PURPOSE:To change a percussion force and to punch those of different hardnesses with good efficiency by providing a 2nd spring as well on the 1st spring for pressing a frame side ratchet gear opposed to a bit side ratchet gear. CONSTITUTION:A 1st spring 6 always acts and a 2nd spring 7 acts via a spring receiver 8 on a frame side ratchet gear 4 opposed to a bit side ratchet gear 3. When the action of the 2nd spring 7 is cut off by moving the spring receiver 8, the frame side ratchet gear 4 changes over the pressing force of the frame side ratchet gear 4 by combining the 1st spring 7 and 2nd spring 7. The percussion force acting on the bit can thus be changed over, a soft one and hard one can be punched with a respectively adaptive percussion force and the efficiency in punching can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibratory drill that includes a pair of ratchet gears that axially mesh on a shaft that holds a bit.

[Prior Art] A vibrating drill for drilling into concrete or the like is equipped with a vibrating mechanism that not only rotates the bit but also strikes the bit in the axial direction.

Such a vibration mechanism for hitting a bit is configured to generate vibration in the axial direction by engaging ratchet gears that form unevenness in the axial direction in the axial direction.

The ratchet gears on the bit side constituting the pair of ratchet gears are fixed to the bit side via a shaft so as to face each other so as to impact the bit in the axial direction.

Furthermore, the ratchet gear on the frame side is pushed toward the bit side by a spring, and is configured to vibrate with the ratchet gear on the bit side.

With this configuration, the frame-side ratchet gear hits the bit-side ratchet gear by the expansion and contraction of the spring, and the workpiece can be perforated by impact with an appropriate pressure.

[Problems to be Solved by the Invention] However, in this type of vibration drill, since the pressing force of the spring is constant, the striking force is constant, and it is difficult to hit hard or soft objects, such as concrete or bricks with different hardness. It was commonly used for drilling various holes without changing the intensity of vibration.

For this reason, what can be efficiently drilled is limited by the setting of the spring.

The present invention was made in view of these circumstances, and
The purpose of the present invention is to provide a vibration drill that can efficiently drill holes of different hardness.

[Means for Solving the Problems] The present invention is configured such that a bit-side ratchet gear presses a shaft, and includes a first spring that presses a frame-side ratchet gear opposite to this bit-side ratchet gear. The problem arises because a second spring is provided alongside the first spring, a spring receiver is provided between the second spring and the bit side ratchet gear, and the spring receiver is configured to be movable in the axial direction from outside the frame. points are resolved.

[Function] On the frame side ratchet gear, the first spring always acts, and the second spring acts through the spring receiver.

Therefore, by moving the spring receiver, the second
When the action of the spring is cut off, only the first spring acts on the frame side ratchet gear, and the pressing force of the frame side ratchet gear can be switched by combining the first spring and the second spring.

Therefore, the impact force acting on the bit can be switched, and soft and hard materials can be drilled with appropriate impact forces, thereby improving the efficiency of drilling.

[Embodiment] The present invention will be described based on an embodiment shown in the drawings. The figure is a longitudinal sectional view of a main part of a vibration drill according to an embodiment of the present invention.

In the figure, the vibratory drill has a shaft 1 equipped with a bit (not shown) at the end thereof, which is supported by a bearing 2 so as to be movable in the axial direction.

The shaft 1 is provided with a bit-side ratchet gear 3 and a frame-side ratchet gear 4 as a pair.
The bit side ratchet gear 3 is fixed to the shaft,
The frame side ratchet gear 4 is provided so as to be movable in the axial direction without rotating.

The frame side ratchet gear 4 is connected to the frame 5.
The second spring 7 presses the frame-side ratchet gear 4 via the spring receiver 8.

Further, the spring receiver 8 is configured to be moved in the axial direction by an eccentric shaft 9 from outside the frame 5.

The eccentric shaft 9 is moved by rotating a knob 10 provided on the outside of the frame 5 so that an eccentric protrusion 11 that engages with the spring receiver 8 moves the spring receiver 8 in the axial direction. There is.

Further, the shaft 1 is configured to be rotated by a shaft 12 of an electric motor via a gear 13.

In such a configuration, when a bit (not shown) is pressed, the bit-side ratchet gear 3 meshes with the frame-side ratchet gear 4, and the vibration in the axial direction is absorbed by the shaft 1.
This will cause a bit to occur and hit a bit (not shown).

This impact occurs when the frame-side ratchet gear 4 engages with the bit-side ratchet gear 3 and presses the first spring 6 and retreats, and after the ratchet gears have climbed over the peaks of each other, the first spring 6 The frame side ratchet gear 4 hits the bit side ratchet gear 3, thereby generating vibration.

That is, due to the impact force of the first spring 6, the frame side ratchet gear 4 acts as a hammer and hits the bit side ratchet gear 3. Therefore, when the knob 10 is rotated so that the protrusion 11 moves toward the bit-side ratchet gear 3, the spring receiver 8 is no longer restricted by the protrusion 11, and the second spring 7 presses the frame-side ratchet gear 4. It turns out.

Therefore, the frame side ratchet gear 4 is pressed by the first spring 6 and the second spring 7, and the impact force increases.

It is convenient to configure the impact force so that it can be easily changed using the knob 10.

[Effects of the Invention] According to the present invention, despite the simple configuration, by using the first spring and the second spring in combination, the impact force can be changed, and in the case of a hard object, the impact force can be changed. If the material is soft, the striking force can be weakened, and the impact force can be weakened to make the hole more efficient.

[Brief explanation of drawings]

The figure is a longitudinal cross-sectional view of essential parts of a vibratory drill according to an embodiment of the present invention. 1...shaft, 3...bit side ratchet gear 4.
... Frame side ratchet gear 5... Frame, 6... First spring, 7... Second spring, 8... Spring receiver, 9... Wound shaft,
11... Protrusion.

Claims (1)

[Claims] In a vibrating drill equipped with a pair of ratchet gears that mesh in the axial direction on a shaft that holds a bit, the bit-side ratchet gear is configured to press the shaft, and the frame-side ratchet gear that opposes the bit-side ratchet gear is pressed. a second spring attached to the first spring; a spring receiver between the second spring and the bit-side ratchet gear; A vibration drill characterized by being configured to be movable.