JPH0783986B2 - Vibrating drill - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vibration drill that rotates a bit and simultaneously vibrates the bit in the axial direction.

[Background Art] A vibration drill is generally used to drill concrete or mortar, but the brittleness differs between concrete and mortar, and the same concrete can be mixed depending on whether the aggregate is pebble or sand. Brittleness is different Here, if the drilling work with a vibrating drill is to be performed efficiently, the impact force that the vibrating drill gives to the surface to be drilled will be increased. If the material is perforated by force, the material to be perforated may be damaged.

Further, in the case of using a storage battery as a power source, there is a limit to the number of punching operations that can be performed, for example, once. In general, when the frequency or amplitude is increased to increase the work capacity, the number of times decreases, and in the opposite case, the work capacity decreases but the number of times increases.

Therefore, it is desired that the work ability can be adjusted according to the work purpose and conditions.

[Object of the Invention] The present invention has been made in view of such a point, and an object of the present invention is to move a movable side cam that is retracted against a spring bias by a sliding engagement to move forward by the spring bias. To provide a vibrating drill that can adjust the work capacity according to the work purpose and conditions in a type in which the spindle is vibrated in the axial direction by the impact shock when colliding with the stationary cam fixed to the spindle. is there.

DISCLOSURE OF THE INVENTION The present invention, however, includes a spindle that can freely move in the axial direction within a predetermined range and is driven to rotate by the output of a motor, and a fixed cam fixed to the spindle and a non-rotatable cam. A movable side cam that is movable in the axial direction and that is biased toward the fixed side cam by a spring is provided, and the sliding cam of the teeth provided on the facing surfaces of both cams and the movable side cam are biased. In a vibration drill that gives axial vibration to a spindle having a fixed side cam by a spring that
A vibration adjusting member that controls the meshing height of both cams by limiting the amount of movement of the movable cam toward the fixed cam is provided.
The vibration adjusting member is rotatably arranged at the tip of the housing and has a switching handle having a plurality of stepped contact portions on its inner surface; and a protrusion formed on the peripheral portion of the upper movable cam. It is characterized in that it comprises a switching plate which is movably supported in the axial direction with respect to the housing and has one end abutting on the abutting portion and the other end abutting on the projecting piece.

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiment. The housing 1 includes a chuck 8 having a bit 9 mounted on its front end.
As shown in FIG. 1, a grip 16 is extended from the lower portion of the rear end, and a battery pack 17 is attached to the lower end of the grip 16. Reference numeral 11 is a switch handle, 12 is a rotation direction switching handle, and 13 is a rotation speed switching lever. Further, the chuck handle 14 used when the bit 9 is attached to and detached from the chuck 8 is held in a recess on the outer surface of the rear portion of the housing 1. However, this holding is not done mechanically, It is held by the leakage magnetic flux of the magnet 2a of the motor 2 housed in the rear part of the motor 1. In the figure, 29 is a magnetic material. When the mechanical holding means is used, the "falling" of the holding means becomes a problem, but since the leakage magnetic flux of the motor 2 is used, it is always held reliably. In order to make the distance between the motor 2 and the chuck housing 1 as short as possible, a recess is provided in the housing 1 so that the chuck housing 1 can be housed in this recess. It is more desirable to make 1 thin. Of course, a mechanical holding means may be used together.

A pinion 21 is attached to an output shaft 20 of the motor 2 housed in the rear portion of the housing 1 in a state where its axial direction is the front-back direction. The pinion 21 meshes with a gear 22 at one end of an intermediate shaft 23 whose front and rear ends are supported. Further, the intermediate shaft 23 includes a pair of gears 24 and 25 having different numbers of teeth. Then, the gear 2 that meshes with these gears 24 and 25
6,27 are attached to the drive shaft 3. The drive shaft 3, which is installed parallel to the motor 2 and the intermediate shaft 23 and is rotatable about its axis by the bearing 40, supports the gears 26 and 27 rotatably around the shafts. With the movement of the key 28 by the operation of the rotation speed switching lever 13, either of the gears 26, 27 is connected so as to rotate integrally with the drive shaft 3. That is, the drive shaft 3 transmits the rotation of the intermediate shaft 23 by meshing with any combination of the gear 24 and the gear 26, or the gear 25 and the gear 27, and the gear 26 or the gear 26 that does not contribute to the rotation transmission. The gear 27 becomes idle with respect to the drive shaft 3.

A planetary mechanism 4 is provided at the tip of the drive shaft 3. The planetary mechanism 4 includes a sun gear 41 formed by providing teeth on the outer surface of the tip of the drive shaft 3, an internal gear 42 integrally formed on the inner surface of the gear case 6, and a plurality of planetary gears meshing with the sun gear 41 and the internal gear 42. Gear 43, and shaft 45 that supports each planet gear 43
The planet carrier 44 is provided integrally with the rear end of the spindle 5 having the chuck 8 for holding the bit 9 at the front end. Although the internal gear 42 is formed integrally with the gear case 6 as described above, it is formed of a molded product to reduce the axial vibration of the reduction gear mechanism and reduce the load on each gear. ing.

A mechanism for applying axial vibration to the spindle 5 is provided by a cam 62 fixed to the spindle 5 by press fitting.
And a cam 61 that is loosely fitted to the spindle 5 and is rotatable and axially movable with respect to the spindle 5. These cams 61 and 62 have a fifth
A slanted surface that causes sliding engagement as shown in FIGS. 7 to 7 is formed. The cam 61 is urged in the direction of meshing with the cam 62 by a spring 63 installed between the back surface of the cam 61 and the gear case 6, and a projecting piece 65 protruding from the peripheral edge is formed on the inner surface of the gear case 6. By engaging with the axially long groove 69, it is prevented from rotating. In the figure, 47 is a bearing that supports the spindle 5 rotatably and axially movably, and 48 is fixed to the spindle 5 and the spindle 5 between the bearing 47 and the bearing 47.
A ring that limits the retractable range of the, 50 is dustproof rubber,
51 is a washer fixed to the tip surface of the gear case 6 with screws, 52 is a support plate, 80 is a retaining ring for the bearing 47, 81 is a stopper for restricting the movement of the cam 62 and the axial movement range of the spindle 5. It is a ring.

At the tip of the housing 1, the tip of the gear case 6 and the washer
A switching handle 7 is provided which is supported between the switching handle 7 and the shaft 51 and is rotatable about its axis. The switching handle 7 has a cam surface on the inner surface thereof.
72 is stuck. The switching ring 7 has a switching plate 71 slidable along the groove 69 in the gear case 6.
Is in contact with the front end of. The contact portion with the switching plate 71 has a stepped shape as shown in FIG.

Then, as shown in FIG. 2, when the switching plate 71 is positioned forward, the rotation of the drive shaft 3 due to the output of the motor 2 is decelerated by the planetary mechanism 21 to rotate the spindle 5 and the bit 9. When the pair of cams 61 and 62 are brought into contact with each other by the reaction force of pressing the bit 9 against the surface to be drilled, the cam 62 rotates together with the spindle 5 while the cam 61 and the gear case 6 Since the cams 61 and 62 are prevented from rotating by engagement, they are in the state shown in FIGS. 2 and 5 when the inclined surfaces of the facing surfaces of the cam 61 and the cam 62 are in mesh with each other, but as shown in FIG. Thus, when the cam 62 gets over the inclined surface of the cam 61 by its rotation, the cam 61 immediately after this hits the cam 62 by the bias of the spring 63. As a result, the axial vibration is transmitted to the bit 9.

On the other hand, when the switching handle 71 is rotated to push the switching plate 71 rearward through the switching ring 72,
The switching plate 71 whose rear end is in contact with the projection 65 of the cam 61 pushes the cam 61 rearward against the spring 63, and as shown in FIG. 4, does not come into contact with the cam 62. Put in position. Since the rearward movement range of the spindle 5 is restricted by the ring 48 and the bearing 47, at this time, even if the bit 9 is pressed against the surface to be drilled, the cams 61 and 62 do not come into contact with each other. , Only rotation is transmitted to the bit 9.

Then, the switching plate by rotating the switching handle 7
When the amount of retreat of 71 is reduced, that is, when the cam 61 is positioned in the intermediate state between the state shown in FIG. 2 and the state shown in FIG. 4, as shown in FIG. 6 or FIG. , The maximum meshing height of both cams 61, 62 becomes low (h> h '>
h ″). In this case, although the compression amount of the spring 63, which is the power for generating the vibration by the cams 61 and 62, is the same,
Since the speed of the cam 61 when the 61 collides with the cam 62 is different, the amplitude of the vibration generated varies depending on the meshing height.If the meshing height is lowered, the amplitude will be small and the meshing height will be high. The higher the height, the larger the amplitude. Further, when the meshing height is small, the load applied to the motor 2 also changes because the amount of work when the cam 62 retracts the cam 61 differs due to its rotation. As a result, as shown in FIG. 8, as the engagement height of the cams 61 and 62 is increased, the working capacity (perforation speed) is increased, and at the same time, the number of perforations that can be performed in one charge is decreased, and conversely. As the meshing height is reduced, the workability is reduced, but the number of perforations that can be performed by one charge is increased.

[Effects of the Invention] As described above, in the present invention, the moving height of the movable cam toward the fixed cam is controlled by the vibration adjusting member so that the meshing height of the pair of cams, which is vibrated by the sliding meshing, is controlled. The movable cam, which is retracted against the spring bias due to the sliding engagement, moves forward with the spring bias and collides with the fixed cam fixed to the spindle due to the impact impact on the spindle. In the type that gives axial vibration, it is possible to change the vibration amplification, so that it is possible to perform work according to the conditions such as brittleness of the material to be perforated and the work purpose. In addition to being able to prevent accidents such as damage to the battery, those that use a storage battery as a power source can be used properly according to the storage battery capacity. A vibration adjusting member that controls the meshing height of both cams by limiting the amount of movement of the movable side cam toward the fixed side cam is rotatably arranged at the tip of the housing and has a stepped contact part with multiple steps on the inner surface. A switching handle having a protrusion, a protrusion formed on the peripheral portion of the movable cam, and one end of the protrusion supported on the housing so as to be movable in the axial direction.
Since the other end is composed of a switching plate that is brought into contact with the protrusion, the position regulation of the movable-side cam does not shift due to vibration during operation, and the vibration amplitude is stabilized in the adjusted state. Since the vibration adjusting member does not come into contact with the member that rotates by power, the structure can be simplified.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an embodiment of the present invention, FIGS. 2 and 3 are vertical cross-sectional views of the same operation, and FIG. FIGS. 6, 6 and 7 are sectional views showing a state in which the engagement height of the cam is changed, FIG. 8 is a characteristic diagram of the same, and FIG. 9 is a switching plate and a switching ring of the same. 3 is a transverse sectional view taken along the line AA in FIG. 3, and FIG. 10 is a sectional view taken along the line BB in FIG. 9, wherein 1 is a housing, 2 is a motor, 3 is a drive shaft, 5 is a spindle, and 9 Is a bit, 61 and 62 are cams, 63 is a spring, 71 is a switching plate, and 72 is a switching ring.

Claims (1)

[Claims] 1. A spindle which is axially movable within a predetermined range and is rotationally driven by the output of a motor, and a fixed cam fixed to the spindle and non-rotatably axially movable. And a movable side cam that is biased toward the fixed side cam by a spring, and the fixed side is provided by a sliding engagement of teeth provided on mutually facing surfaces of both cams and a spring that biases the movable side cam. In a vibration drill that applies axial vibration to a spindle having a cam, a vibration adjustment member that controls the meshing height of both cams by limiting the amount of movement of the movable side cam toward the fixed side cam is provided. A switching handle rotatably arranged at the tip of the housing and having a plurality of step-shaped contact portions on the inner surface,
A protrusion formed on the peripheral portion of the movable-side cam and a switch that is supported movably in the axial direction with respect to the housing and has one end abutting the abutment and the other end abutting the protrusion. A vibrating drill consisting of a plate.