JPH04240010A - Vibration drill - Google Patents

Abstract

PURPOSE:To easily adjust the strength of impact according to the work content. CONSTITUTION:The initial compression quantity of a spring is made variable with a support part 7 which supports the other end of the following spring 6 whose one end is abutted on a slide cam 52 being made freely movable in the axial direction, in the vibration drill that the vibration in the axial direction is given to a spindle 5 with the slide engagement accompanied by the rotation of the spindle on the uneven face of the slide cam 52 and rotating cam 1, by providing the slide cam 52 energized by a spring 6 toward the rotating cam 51 provided on the spindle 5.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibratory drill that applies not only rotation but also axial vibration to a tool such as a drill bit.

0002

[Prior Art] A vibrating drill has a rotating cam fixed to a spindle that is rotatably driven and supported so as to be movable in the axial direction. A slide cam whose surface facing the uneven surface is an uneven surface is provided, and the slide cam, which can slide freely in the axial direction of the spindle, is biased by a spring toward the rotating cam, and rotates together with the spindle. The cam and the slide cam are configured so that their uneven surfaces are engaged with each other by a spring. When the spindle rotates, the rotating cam, which rotates together with the spindle, rotates while pushing the slide cam back against the spring. Each time the uneven surfaces of the slide cam and the rotary cam shift by one position, the slide cam applies an impact to the spindle through the rotary cam in accordance with the elastic force of the spring.

At this time, the slide cam and the spring biasing it are forced to vibrate by the rotating cam, and the slide cam and the spring constitute one spring mass system. Therefore, the impact given to the tool by the collision between the peaks and valleys on the uneven surfaces of the slide cam and the rotating cam is calculated by the mass of the spring mass system mentioned above and the speed at which the slide cam collides with the rotating cam. will be determined.

0004

[Problem to be Solved by the Invention] In the conventional vibrating drill, since the spring mass system described above is constant, only a constant vibration impact can be obtained.
Depending on the nature of the work, the impact may be too strong or too weak. The present invention has been made in view of these points, and its object is to provide a vibratory drill that can easily adjust the strength of impact depending on the content of the work.

[0005]

[Means for Solving the Problems] The present invention has a spindle that is rotatably driven and has a tool attachment portion at its tip and is pivoted so as to be movable in the axial direction, and a spindle that has an uneven surface on one surface in the axial direction. a rotating cam fixed to the spindle;
A slide cam is provided with an uneven surface on a surface opposite to the uneven surface of the rotating cam, and is loosely fitted into the spindle and biased by a spring toward the rotating cam. In a vibration drill in which axial vibration is applied to the spindle by sliding engagement as the spindle rotates on a surface, the spring has one end in contact with a slide cam and a support part supporting the other end of the spring that is movable in the axial direction. The main feature is that the initial compression amount of the spring is variable, and another feature is that it includes an output adjustment means that changes the output of the drive source in accordance with changes in the initial compression amount of the spring. It is something that exists.

According to the present invention, since the spring force of the spring, which is a factor in the speed when the slide cam collides with the rotating cam, can be adjusted, the strength of the impact can be adjusted. be. Furthermore, when equipped with an output adjustment means that changes the output of the drive source according to changes in the initial compression amount of the spring, the drilling capacity can be adjusted over a wide range, especially when the power source is a battery. It is possible to effectively utilize battery capacity.

[0007]

[Embodiment] The present invention will be described in detail below based on the illustrated embodiment. As shown in FIG.
A battery pack 11 is attached to the lower end of the handle portion of the main body 1, and a switch handle 12 and a rotation direction switching lever 13 are provided on the front side of the handle portion. As shown in FIG. 4, a motor 2 and a gearbox 3 are housed within the main body 1.

The gearbox 3 here is divided into two stages, front and rear, with a reduction section using a three-stage planetary mechanism housed in the front stage, and a vibration generating section housed in the rear stage. To explain from the reduction part based on FIG. 1, this supports a pinion 20 attached to the output shaft of the motor 2, an internal gear 21 fixed to the inner surface of the gearbox 3, a planetary gear 22 that meshes with both, and a planetary gear 22. A carrier 23, an internal gear 24 that is slidable in the axial direction within the gear box 3, and a planetary gear 25 that meshes with the sun gear portion of the carrier 23 and the internal gear 24.
, a carrier 26 supporting this planetary gear 25, an internal gear 27 fixed in the gear box 3, a sun gear section provided on the carrier 26, and the internal gear 2.
7, and a carrier 29 that supports the planet gear 28. The slidable internal gear 24 is configured to rotate as shown in FIG. Lever 16
When the switching lever 15 is slid, the carrier 23 slides in the axial direction and engages with the gearbox 3 shown in FIG.
It is switched to a state in which it engages with the carrier 23 and rotates together with the carrier 23. This means that the reduction ratio can be switched.

Next, the vibration generating section will be explained. This includes a spindle 5 that is supported by bearings 31 and 32 so as to be rotatable and slidable in the axial direction, a rotating cam 51 fixed to the spindle 5, a slide cam 52 loosely fitted to the spindle 5, and a slide cam 52 that is loosely fitted to the spindle 5. The spindle 5 has the chuck 55 attached to its tip, and the rear end of the spindle 5 is slidably connected to the carrier 29 by a spline.

The rotary cam 51 and the slide cam 52 are provided with uneven surfaces each having the same number of teeth radially formed on their opposing surfaces, and are brought into contact with each other by the force of the spring 6, and are made of chrome. It is formed by forging molybdenum steel. One end of the spring 6 is in contact with the slide cam 52, and the other end of the spring 6 is in contact with the support plate 7 via a thrust bearing 62. As is clear from FIG. 5, the support plate 7 is ring-shaped and has a pair of protrusions 71 protruding from its outer periphery. Projection 7 protruding outward
1 is received by an adjustment handle 8 which is screwed into a male thread 19 formed on the outer peripheral surface of the main body 1 . The adjustment handle 8 is constructed by connecting a pair of halves 80, 80 with a screw 82, and has a female thread 81 on its inner circumferential surface that engages with the male thread 19, and further has a female thread 81 on its rear end. A large number of small protrusions 82 protruding toward the front side are provided at intervals in the circumferential direction.

[0011]In this vibratory drill, the spindle 5 is rotationally driven by the motor 2. Further, when the tool attached to the chuck 55 provided on the spindle 5 is pressed against the surface to be drilled, the rotating cam 51 provided on the spindle 5 and the slide cam 52 are engaged with each other, and the rotating cam 51 rotating together with the spindle 5 is rotated with the slide cam. 5
2 is pushed back against the spring 6, and when the slide cam 52 has rotated by one tooth, the slide cam 52 engages with the next tooth under the bias of the spring 6. At this time, the slide cam 52 An impact force corresponding to its own mass and the spring force of the spring 6 is applied to the rotating cam 51.

This impact force can be adjusted by rotating the adjustment handle 8. The adjustment handle 8, which is screwed by this rotation, moves the support plate 7 in the axial direction of the drive shaft 3, as shown in FIG. The initial compression amount of the arranged spring 6 is changed. As a result, the slide cam 52
Since the speed at which the rotating cam 51 collides with the rotating cam 51 changes, the impact force also changes. In other words, if the initial compression amount of the spring 6 is increased, the impact force will be increased, and if the initial compression amount is decreased, the impact force will be decreased.

The adjustment handle 8 has a protrusion 82 as described above.
Since the protrusion 71 of the support plate 7 is inserted between the protrusions 82, the adjustment handle 8 will not be rotated by the force of the spring 6, and the protrusion 82 is used to adjust the impact force. , the rotation of the adjustment handle 8 can be controlled with moderation. Other embodiments are shown in FIG. 6 and below. This is so that the output of the motor 2 changes according to the change in the initial compression amount of the spring 6, and a sliding variable resistor 76 is provided for adjusting the voltage applied to the motor 2. The variable resistor 76 is connected to the support plate 7 by a bar 75 so that the resistance value of the variable resistor 76 changes as the support plate 7 moves. The movement of the support plate 7 causes the spring 6 to
When the initial compression amount of the spring 6 increases, the resistance value of the variable resistor 76 decreases, and as shown in FIG. By changing the amount, the impact force becomes higher, and the perforation ability is synergistically improved. In addition, when the drilling capacity is increased in this way, the time required for drilling is shortened, and as a result, the number of holes to be drilled can be increased in the case of battery-powered machines, which means that the battery capacity can be used more efficiently. It is something that can be done.

[0014]

As described above, in the present invention, the spring force of the spring, which is a factor of the impact force given when the slide cam collides with the rotating cam, can be adjusted, depending on the work content. The impact force can be adjusted to obtain a high impact force, and the impact force can be increased even at low speeds, making it easy to position the hole and drill the hole in a straight line. This provides excellent workability.

Furthermore, if the device is equipped with an output adjustment means that changes the output of the drive source in conjunction with this, the adjustment range of the drilling capacity can be widened, making it more effective at rotational speeds where high impact force is required. This allows for efficient drilling of holes, and when the power source is a battery, the battery capacity can be used effectively.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the present invention.

FIG. 2 is a cross-sectional view when the impact force of the same as above is changed.

FIG. 3 is a side view of the same as above.

FIG. 4 is a cutaway side view of the same as above.

FIG. 5 is an exploded perspective view of a portion for adjusting the initial compression amount of the spring.

FIG. 6 is a sectional view of another embodiment.

FIG. 7 is a circuit diagram similar to the above.

FIG. 8 is an explanatory diagram illustrating the operation same as the above.

[Explanation of symbols]

5 Spindle 6 Spring 51 Rotating cam 52 Slide cam

Claims (2)

[Claims] Claims: 1. A spindle having a tool attachment portion at its tip and rotatably driven and supported so as to be movable in the axial direction; a rotating cam having an uneven surface on one axial direction and fixed to the spindle; , a slide cam having an uneven surface on a surface opposite to the uneven surface of the rotating cam, is loosely fitted into the spindle, and is biased by a spring toward the rotating cam, and the slide cam and the rotating cam are connected to each other by a spring. In a vibration drill in which axial vibration is applied to the spindle by sliding engagement as the spindle rotates on an uneven surface, a support part supporting the other end of the spring whose one end is in contact with the slide cam is movable in the axial direction. A vibratory drill characterized by making the initial compression amount of the spring variable. 2. The vibratory drill according to claim 1, further comprising an output adjusting means for changing the output of the drive source in accordance with a change in the initial compression amount of the spring.