JPH04105809A - Vibration drill - Google Patents

Abstract

PURPOSE:To select the support of a slide cam adaptive for the spindle rotation, by inhibitting vibration, and releasing the inhibit for a vibration drill main body with the slide cam which is loosely fitted to a spindle with its being energized by a spring being interlocked with a rotation number switching means. CONSTITUTION:A spindle 1 is driven at a low speed (first step speed reduction Xsecond step speed reduction X third step speed reduction) in the state of a switching lever 11 being at a low speed position, a regulation member 5a exists in the position apart from the projection piece 3c of a slide cam 3 with its being close to the driving part 6 side, and the slide cam 3 is vibrated in the state of being supported by a spring. The spindle 1 is driven at a high speed (first step reduction X third step reduction) in the state of the switching lever 11 being at a high speed state, the regulation member 5a exists close to a fitting means 7 side an is located at the position abutting on the projection piece 3c of the slide cam 3 when load is applied on the spindle 1, the vibration of the slide cam 3 is inhibitted for the vibration drill main body, the vibration drill main body is moved in the axial direction via the slide cam 3 according to the rotation of a rotating cam 2, and the inertia force is applied on the rotating cam 2 impactly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibratory drill that rotates a tip tool and vibrates in the axial direction.

[Conventional technology]

Conventional vibrating drills are generally constructed as shown in FIG. 4 in order to generate vibrations.

That is, it is supported by bearings 8, 8 so as to be movable in the axial direction, and one end is provided with attachment means 7 for attaching the tip tool, and the other end is movable in the axial direction. The spindle 1 is connected to a drive unit 6 consisting of a morph, a speed reduction mechanism made by superimposing three planetary gear mechanisms, etc., and the spindle 1 has a large number of ring-shaped teeth that are uneven in the axial direction. A fixed rotary cam 14, a slide cam 15 having teeth 15a corresponding to the rotary cam 14, biased by a spring toward the rotary cam 14, and loosely fitted to the spindle 1, and a planetary gear mechanism of the drive section. A rotation speed switching means is provided for switching the rotation speed of the spindle between "low speed" and "high speed" using an engaged rotation speed switching lever.

In this case, when an axial load is applied to the tip tool, the slide cam 15 is spring-biased as the rotary cam 14 rotates.
is moved in the axial direction against elastic force.

When the rotary cam 14 finishes rotating for one tooth, the slide cam 1
5 instantly meshes with the next tooth. At this time, an impact force corresponding to the magnitude of the elastic force is applied to the rotating cam 14. In this way, each time the rotary cam 14 rotates once, a shock is applied to the tip tool as many times as the number of meshing teeth, causing it to vibrate.

There is also a device configured as shown in FIG.

In this case, a fixed cam 16 is provided in place of the slide cam 15 described above, and a spring 17 is provided between the fixed cam 16 and the rotating cam 14. This fixed cam 16 is fixed to a gear case 9 that houses and supports the drive section 6. Then, when an axial load is applied to the tip tool, as the rotary cam 14 fixed to the spindle 1 rotates, the gear case 9, that is, the vibration drill body (not shown) is moved in the axial direction via the fixed cam 16. When the rotary cam 14 completes one tooth's worth of rotation, the fixed cam 16 meshes with the next tooth. At this time, an inertial force corresponding to the magnitude of the force supporting the vibrating drill body is impulsively applied to the rotating cam 14. In this way, each time the rotary cam 14 rotates once, a shock is applied to the tip tool as many times as the number of meshing teeth, causing it to vibrate.

[Problem to be solved by the invention]

In the former type of vibrating drill as described above, the reaction force of the impact applied to the tip tool is transmitted to the vibrating drill body via the spring that biases the slide cam, so it is uncomfortable for the hand supporting the vibrating drill body. It is difficult to transmit vibrations. However, since the slide cam is biased by a spring, there is a limit to increasing the drilling efficiency due to the balance between the size of the spring and the output of the motor. In the latter case, the reaction force of the impact applied to the tip tool is transmitted to the vibrating drill body via the fixed cam, so that the vibration is transmitted to the hand supporting the vibrating drill body. However, since an inertial force corresponding to the magnitude of the force supporting the vibrating drill body is impulsively applied to the rotating cam, the impact force is increased and the drilling efficiency is increased. Furthermore, when the rotation speed switching means is set to "low speed", the vibrating drill body cannot be held for a long time. This is because this product is also used as a screwdriver, so the rotation speed switching means is set to "low speed".
When selected, the spindle rotates at 600 to 800 r, p, and m. In addition, the number of teeth on the cam is limited to 15 to 18 teeth depending on the size of the vibrating drill body. As a result, the vibration frequency at "low speed" is 9000 to 14400 b, p, m. This frequency range is, for example, a frequency of 18 at "high speed".
Compared to the frequency ranges of 000 to 28800b, p, and m, experiments have shown that hands feel numb.

The present invention has been made in view of the above circumstances, and its purpose is to provide a vibratory drill that has good drilling efficiency and that causes less vibration in the hand during drilling.

[Failure to solve the problem]

In order to achieve the above-mentioned object, the vibration drill of the present invention is supported so as to be movable in the axial direction, and is provided with attachment means for attaching a tip tool to one end of the vibration drill. A spindle that protrudes and is connected to a drive unit with the other end movable in the axial direction, a rotating cam that has many teeth that are uneven in the axial direction and is fixed to the spindle, and a slide cam having corresponding teeth, biased by a spring toward the rotating cam and loosely fitted to the spindle; and a rotation speed switching means that engages with the drive section and switches the rotation speed of the spindle with a rotation speed switching lever. The vibratory drill is configured such that vibration of the slide cam relative to the vibratory drill body is suppressed or released from vibration in conjunction with the rotation speed switching means.

[Effect]

According to this configuration, the slide cam, which is biased by a spring and loosely fitted to the spindle, is linked to the rotation speed switching means to suppress or release the vibration of the slide cam relative to the vibration drill body. Therefore, the slide cam support that matches the spindle rotation speed can be selected.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 3.

Reference numeral 1 denotes a spindle, which has six stages of shaft parts, one end of which is connected to the output side of a drive part 6 by engagement of a spline or the like, and the other end of which has attachment means 7 for attaching a tip tool. And, it is supported by bearings 8, 8 in a state where it can move in a predetermined direction in the axial direction. The speed reduction device of this drive unit 6 is made up of a three-stage planetary mechanism, in which a pinion 6b fixed to the output shaft of a motor 6a is connected to the input side, and a carrier 6 to the output side.
The spline shaft portion 18 of the spindle 1 and the like are connected to c.

This attachment means 7 is made of a drill chaff or the like, and is screwed onto a threaded portion 1b provided at the tip of the spindle 1. This movement in the axial direction is caused by the rotating cam 2 (described later) fixed to the shaft of the fourth stage (hereinafter counted from the shaft in which the threaded part 1b is provided) or the end face of the shaft of the second stage to the bearing 8. It is possible to reach the regulated position.

Reference numeral 2 denotes a rotating cam, which is made of a sintered alloy and has a large number of teeth 2a with a serrated cross section that is uneven in the axial direction. Reference numeral 3 fixed to the shaft of the eye is a slide cam, which is made of a sintered alloy, and has teeth 3a corresponding to the teeth 2a of the rotating cam 2 on one end surface, and a shaft of the fourth stage of the spindle 1 on the shaft center. It has a hole 3b that fits loosely into the gear case 9, and protruding pieces 3c that engage with the grooves 9a of the gear case 9 on three sides of the outer periphery and protrude to the outer periphery. Ru. This slide cam 3 is gear case 9
The direction of rotation of the spindle 1 is regulated by engagement with a groove 9a provided in the axial direction.

4 is rotation speed switching means, which includes a switching lever 11, a connector 12,
It consists of a speed change joint 13. The switching lever 11 is connected to the connector 1
It has a locking part 11a that locks the vibration drill 2, and is held in a movable state between two stations, ``low speed'' and ``high speed'', provided in the axial direction, and a portion protrudes from the outer shell of the vibration drill body. It will be arranged as follows. The connector 12 has a locking portion 11a at one end.
The other end is connected to a regulating means 5, which will be described later, and the intermediate portion has a retaining portion 12a which engages with a speed change joint 13, which will be described later. The transmission joint 13 is made of a metal plate material, is formed into a substantially U-shape, and has a second stage ring gear 6, which will be described later, near both ends.
A pin 13a that engages with the groove 62a of No. 2 is fixed, and has a hole 13b that fits into a fulcrum portion 9b protruding from the gear case 9 inwardly. The second stage ring gear 62 has 3
This is an internal gear of a second stage planetary gear mechanism arranged in a planetary gear mechanism in which the stages are overlapped, and has a groove 62a on the outer periphery for retaining the pin 13a, and teeth 9c provided on the inner periphery of the gear case 9.
It has teeth 62b that mesh with.

Reference numeral 5 denotes a regulating means, which connects a regulating member 5a that fits on the outer periphery of the tip of the gear case 9 and is disposed so as to face the end surface of the protruding piece 3c on the drive section 6 side to the connector I2 to prevent the shaft. It is supported so as to be movable in the center direction and is held at a predetermined position in the gear case 9.

Next, the operation of this device will be explained.

FIG. 1 shows a state in which the switching lever 11 is in the "low speed" position, and the center part of the speed change joint 13 connected to the connector 12 is located on the driving part 6 side with respect to the fulcrum part 9b, Pin 13a is located on the opposite side. As a result, the second stage ring gear 62 transfers its internal gear to the second stage planetary gear 65.
Then, the teeth 62b on the outer periphery mesh with the teeth 9c provided on the inner periphery of the gear case 9. As a result, the second-stage ring gear 62 is fixed, the three-stage planetary gear mechanism is in a superposed state, and the spindle 1 is at a low speed (1-stage reduction x 2-stage reduction x 3-stage reduction).
It is driven by. At this time, the regulating member 5a is located closer to the drive section 6 side and away from the protruding piece 3c of the slide cam 3. That is, the slide cam 3 vibrates while being supported by the spring.

FIG. 2 shows that when the switching lever 11 is in the "high speed" position, the center part of the transmission joint 13 connected to the connector 12 is located on the attachment means 7 side with respect to the fulcrum part 9b, and the transmission joint 13 is The pin 13a is located on the opposite side. As a result, the internal gear of the second stage ring gear 62 meshes with a first stage outer sun gear 61a and a second stage planetary gear 65, which will be described later. and,
Teeth 62b on the outer periphery and teeth 9c provided on the inner periphery of the gear case 9
The mesh becomes disengaged.

The first stage outer sun gear 61a is formed on the outer periphery of a carrier 61b having a shaft that supports the first stage planetary gear 64 of the first stage planetary gear mechanism, and is integrally formed with the first stage sun gear 61. As a result, the first sun gear 61 and the second sun gear 66 are driven integrally, and the spindle 1 is driven at high speed (
Driven by 1 step reduction x 3 step reduction). At this time, the regulating member 5a is in a position where it comes into contact with the protruding piece 3C of the slide cam 3 when a load is applied to the spindle 1 as it approaches the attachment means 7 side.

That is, the vibration of the slide cam 3 is suppressed with respect to the vibrating drill body. As a result, as the rotary cam 2 rotates, the vibration drill main body is moved in the axial direction via the slide cam 3. When the rotary cam 2 completes the rotation of one tooth, the slide cam 3 meshes with the next tooth. At this time, an inertial force corresponding to the magnitude of the force supporting the vibrating drill body is impulsively applied to the rotating cam 2. In this way, each time the rotary cam 2 rotates once, a shock is applied to the tip tool as many times as the number of meshing teeth, causing it to vibrate.

In the above-mentioned vibratory drill, the slide cam 3 is supported by a spring when the rotation speed switching means 4 is selected as "low speed", and the slide cam 3 is supported by the regulating means 5 when "high speed" is selected.

〔effect〕

The vibration drill of the present invention suppresses the vibration of the slide cam relative to the vibration drill body in conjunction with the rotation speed switching means,
Since this restraint is released, the slide cam is supported by the spring when driving at "low speed" and the vibrations during drilling are suppressed from being transmitted to the hand, and the slide cam is restricted when driving at "high speed". By supporting the vibrating drill body with means, the inertia force of the vibrating drill body and the force supporting it can effectively contribute to the impact, thereby improving drilling efficiency.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a selected state with a low vibration frequency. Similarly, FIG. 3 is a cross-sectional view of a main part of a selected state with a high vibration frequency. Similarly, a sectional view of the rotation speed switching means part, No. 4
The figure is a sectional view of a main part of a conventional example, and FIG. 5 is a sectional view of a main part of another conventional example. 1 - Spindle, 2 - Rotating cam, Meter - Slide cam, 4 - Rotation speed switching means, 5 - Regulation means, 5a - Regulation member, 6 - Drive section, 7 - Attachment means. Patent applicant Matsushita Electric Works Co., Ltd. Agent Patent attorney Narji Sato (and 1 other person) Figure 3 Figure 4

Claims (1)

[Claims] (1) It is supported by a shaft so that it can be moved in the axial direction, and one end has a mounting means for attaching a tip tool so that it protrudes from the vibration drill body, and the other end can be moved in the axial direction. a spindle connected to the drive unit in a state of A vibratory drill equipped with a slide cam that is biased and loosely fitted into the spindle, and a rotation speed switching means that engages with the drive part and switches the rotation speed of the spindle with a rotation speed switching lever, the rotation speed switching means A vibratory drill characterized in that the vibration of a slide cam with respect to a vibratory drill body is inhibited or the vibration of the vibratory cam is released.