JP2009196044A - Hammer drill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clutch member with excellent slidability by suppressing occurrence of large friction between the clutch member and the contact part of a changeover member and also suppress an increase in the length of a hammer drill in the direction of a countershaft. <P>SOLUTION: This hammer drill comprises a hammering element 9 hammered by the reciprocating motion of a piston, an end tool hammered through the hammering element, and the changeover member 12 capable of changing over the transmission of rotation between on and off by the clutch member 6. The clutch member comprises a first member 6A secured onto the countershaft 5 and a second member 6B having an inner peripheral surface which covers the outer peripheral surface of a part of the first member and rotatable about the axis of the countershaft relative to the first member while using the outer peripheral surface and the inner peripheral surface as sliding surfaces. The changeover member is allowed to come into contact with the second member. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hammer drill having a switching member that can turn on / off a hammer by striking or rotating a tip tool using an intermediate shaft and moving a clutch member in the axial direction of the intermediate shaft.

  A conventional hammer drill will be described with reference to a part of FIG. The conventional hammer drill has a motor 1 inside a housing 2. The housing 2 includes a motor housing 2A and a gear housing 2B. A pinion 1A is cut on the motor shaft of the motor 1, and a fan 1B is provided on the motor shaft so as not to rotate with the shaft.

  The rotation of the pinion 1 </ b> A is engaged with an intermediate shaft gear 5 </ b> A provided on the intermediate shaft 5 so as not to rotate with the intermediate shaft 5. By this engagement, the rotation of the motor 1 is transmitted to the intermediate shaft 5. A reciprocating bearing 7 is provided on the intermediate shaft 5 so as to be rotatable with the intermediate shaft. On the intermediate shaft 5, a clutch member is provided so as not to rotate with the intermediate shaft, and a spring 5 </ b> B that is an elastic body is provided so that the clutch member is urged toward the reciprocating bearing 7. The reciprocating bearing 7 has cut reciprocating bearing teeth 7A so that it can be engaged with the clutch member teeth cut in the clutch member.

  The reciprocating bearing 7 can convert the rotation of the intermediate shaft into the reciprocating motion of the piston 7 </ b> B, and can convert the rotation of the intermediate shaft 5 into pressure fluctuations in the air chamber 8. Due to the pressure fluctuation, the striker 9 reciprocates, the intermediate piece 10 is hit, and the intermediate piece 10 hits a tip tool (not shown).

  On the intermediate shaft 5, intermediate teeth 5C are cut, and are engaged with cylinder teeth 11A connected to the cylinder 11 holding the tip tool.

  In this way, the tip tool is configured to transmit impact and rotation.

  When the operation member 12 is rotated, the clutch member is provided against the biasing force of the spring 5B, which is an elastic body, because the contact portion 12A of the switching member is eccentrically provided with respect to the center of the switching member. The member is on the intermediate shaft 5 and can be moved to the counter-motor 1 side. As a result, the engagement between the reciprocating bearing teeth 7A and the clutch member teeth 6A1 is disengaged, so that the rotation of the clutch member 6 is not transmitted to the reciprocating bearing 7.

However, although the contact portion 12A of the switching member is always in contact with the clutch member, the clutch member 6 continues to rotate and a large friction is generated between the contact portion 12A of the switching member and the switching member. . Due to this friction, the contact portion 12A may be damaged due to a rise in the temperature of the member and a load applied during the contact. As described above, when the contact portion 12A is damaged, it becomes impossible to engage and disengage the reciprocating bearing teeth and the clutch member teeth, and it becomes impossible to turn on / off the transmission of the impact, and the transmission of the impact can be prevented. In some cases, it was always on. (For example, see Patent Document 1)
JP 2006-55958 A

  Japanese Patent Application Laid-Open No. 2006-55958 describes a configuration in which a thrust bearing is provided on the clutch member and the switching member is less subject to large friction. In order to fix the clutch member, the thrust bearing, and the thrust bearing, Since the press-fitted sleeve overlaps in the axial direction of the intermediate shaft, the sleeve extends in the axial direction of the intermediate shaft.

  In the case as described above, the present invention can extend the life by suppressing the occurrence of large friction between the clutch member and the switching member abutting portion. An object of the present invention is to provide a clutch member having a compact length and good slidability.

  An object of the present invention is to provide a motor, an intermediate shaft that transmits the rotation of the motor and rotates, and a reciprocating motion conversion mechanism that is rotatably provided on the intermediate shaft and that can convert the rotation of the intermediate shaft into a reciprocating motion of a piston. A clutch member substantially fixed on the intermediate shaft and capable of turning on or off transmission of rotation of the intermediate shaft to the reciprocating motion conversion mechanism, a striker to be struck by the reciprocating motion of the piston, and the striker A hammer drill having a tip tool that is struck via a clutch and a switching member that can switch transmission of rotation on or off by the clutch member, wherein the clutch member is fixed on the intermediate shaft. 1 member and an inner peripheral surface covering a part of the outer peripheral surface of the first member, and the intermediate shaft with respect to the first member with the outer peripheral surface and the inner peripheral surface as sliding surfaces. The second part that can rotate around the axis Has the door, the switching member is the hammer drill, characterized in that said a second member and can contact, can be achieved.

  The hammer drill according to claim 1, wherein the clutch member has an inner peripheral surface that covers a part of the outer peripheral surface of the first member fixed on the intermediate shaft, and the outer peripheral surface and the inner peripheral surface The surface is a sliding surface, and has a second member that can rotate relative to the first member about the axis of the intermediate shaft as a center of rotation, so that the switching member can come into contact with the second member. Accordingly, the transmission of rotation can be turned on / off by the clutch member. For this reason, it is possible to extend the life of the switching member by suppressing large friction between the switching member and the second member. In addition, since there is a sliding surface between the outer peripheral surface of the first member and the inner peripheral surface of the second member, it is possible to provide a compact hammer drill that is suppressed from extending in the axial direction of the intermediate shaft. . Furthermore, since a clutch member can be comprised by the 1st member and the 2nd member, the increase in a number of parts can be suppressed.

  By using the hammer drill according to claim 2, a configuration in which a sliding member is provided between the first member and the second member, the first member and the second member are provided. Generation of friction can be suppressed, and generation of friction between the second member and the switching member can be further suppressed. For this reason, the switching member can have a longer life.

  Since the lubricating oil can be supplied between the first member and the second member by the hole by using the hammer drill according to claim 3, the first member and the second member It is possible to further suppress the occurrence of friction between the two. For this reason, the switching member can have a longer life.

  An embodiment of the hammer drill of the present invention will be described with reference to FIG.

  The hammer drill of the present invention has a motor 1 inside a housing 2. The housing 2 has a motor housing 2A and a gear housing 2B. A pinion 1A is cut on the motor shaft of the motor 1, and a fan 1B is provided so as not to rotate with the shaft.

  The pinion 1A is engaged with an intermediate shaft gear 5A provided on the intermediate shaft 5 so as not to rotate with the intermediate shaft 5. By this engagement, the rotation of the motor 1 is transmitted to the intermediate shaft 5. A reciprocating bearing 7 is provided on the intermediate shaft 5 so as to be rotatable with the intermediate shaft 5. On the intermediate shaft 5, the clutch member 6 is provided so as not to rotate with the intermediate shaft, and a spring 5 B that is an elastic body is provided so that the clutch member 6 is biased toward the reciprocating bearing 7. Yes. The reciprocating bearing 7 has cut reciprocating bearing teeth 7A so that the clutch member teeth 6A cut into the clutch member 6 can be engaged.

  The reciprocating bearing 7 can convert the rotation of the intermediate shaft 5 into the reciprocating motion of the piston 7 </ b> B, and can convert the rotation of the intermediate shaft 5 into pressure fluctuations in the air chamber 8. Due to the pressure fluctuation, the striker 9 is hit and the meson 10 is hit. The strike of the meson 10 strikes a tip tool (not shown).

  Further, on the intermediate shaft 5, intermediate shaft teeth 5C are cut on the entire circumference in the vicinity of the end portion on the side opposite to the motor, so that the end tool can be held, and the cylinder 11 is rotatably supported by the gear housing 2B. The cylinder teeth 11A to be connected are engaged. For this reason, the rotation of the intermediate shaft 5 is transmitted to the tip tool via the cylinder 11.

  In this way, the tip tool can be struck and rotated.

  The switching member 12 of FIG. 1 is provided so as to be rotatable with respect to the gear housing 2B. Further, as shown in FIGS. 3 and 4, a contact portion 12 </ b> A is provided at a position eccentric from the rotation center L. As shown in FIG. 2, the contact portion 12 </ b> A can contact the clutch member 6. The switching member 12 opposes the clutch member 6 on the intermediate shaft against the biasing force biased so that the reciprocating bearing teeth 7A and the clutch member teeth 6A1 are engaged by the spring 5B which is an elastic body. It can be moved in the direction of the motor 2.

  FIG. 5 shows the clutch member 6 of the hammer drill according to the first embodiment of the present invention. The clutch member 6 includes a first member 6A that is non-rotatable by press-fitting into the intermediate shaft 5, a second member 6B that is rotatably provided with respect to the first member 6A, and a shaft of the second member 6B. And a third member 6C that restricts movement in the direction. The second member 6B is rotatable relative to the first member 6A about the axis of the intermediate shaft 5 as the rotation center, and the outer peripheral surface of the first member 6A and the inner periphery of the second member 6B. The surfaces are in contact with each other and are sliding surfaces. The second member 6B is provided with a contact portion 6B1 that can contact the contact portion 12A of the switching member 12.

  With the above-described configuration, the clutch member 6 is attached to the motor 1 side on the intermediate shaft 5 by the spring 5B that is an elastic body via the third member 6C provided on the first member 6A of the clutch member 6. By energizing, the clutch member teeth 6A1 and the reciprocating bearing teeth 7A can be engaged.

  The clutch member which comprises the hammer drill of 2nd Embodiment is shown in FIG.6, FIG7 and FIG.8. The second member 6B is provided with four holes 6B2 exposing a part of the first member 6A at equal intervals in the circumferential direction of the second member 6B. Since the lubricating oil is sealed in the gear housing 2B, the lubricating oil is supplied to the hole 6B2, so that the gap between the outer peripheral surface of the first member 6A and the inner peripheral surface of the second member 6B is increased. It is possible to easily perform lubrication. The second member 6B is provided with four grooves 6B3 extending in the axial direction thereof. The groove 6B3 is provided on a part of the inner peripheral surface that contacts the first member 6A of the second member 6B, and is connected to the hole 6B2. For this reason, the lubricating oil can be supplied from the hole 6B2 to the groove 6B3, and when the second member 6B rotates, the lubricating oil is supplied from the groove 6B3 in the rotation direction. The mobility can be increased.

  FIG. 9 shows the clutch member 6 of the hammer drill according to the third embodiment. A bearing 6D, which is a sliding member, is provided between the second member 6B and the first member 6A. Thus, the slidability can be increased by providing the bearing 6D between the first member 6A and the second member 6B.

  Operation | movement of the hammer drill which shows one Embodiment of this invention is demonstrated.

  FIG. 1 shows how rotation and impact are performed on the tip tool.

  When an operator holds a handle or the like that is a part of the housing 2 in a state where a plug (not shown) at the end of the power cord 4 is put in an outlet (not shown) and operates the switch 3, electric power is supplied to the motor 1. The motor 1 is rotated by electric power. By the rotation, the fan 1B provided on the rotation shaft of the motor rotates, air is introduced into the housing 2 from a part of the housing 2, and the motor 1 is cooled. Further, a pinion 1A is provided on the rotating shaft of the motor 1, and the rotation is transmitted from the pinion 1A to the intermediate shaft gear 5A. Since the intermediate shaft gear 5A is provided by press fitting so as not to rotate with the intermediate shaft 5, the intermediate shaft 5 rotates. Intermediate shaft teeth 5 </ b> C are provided on the intermediate shaft 5, and the rotation is transmitted to the cylinder teeth 11 </ b> A provided in the cylinder 11 so as not to rotate. Due to the rotation of the cylinder 11, the rotation is transmitted to the tip tool held by the cylinder 11. This rotation is always transmitted when the switch 3 is operated and the motor 1 is rotating.

  A clutch member 6 is provided on the intermediate shaft 5, and the clutch member 6 is always urged on the intermediate shaft 5 by a spring 5 </ b> B that is an elastic body in the direction of the motor 1. Therefore, as shown in FIG. 1, when the contact portion 12A of the switching member 12 does not contact the clutch member 6, the clutch member teeth 6A1 and the reciprocating bearing teeth 7A are engaged. The first member 6 </ b> A of the clutch member 6 is provided so as not to rotate with the intermediate shaft 5, and rotates integrally with the intermediate shaft 5. As shown in FIG. 1, the reciprocating bearing 7 is rotatably provided with the intermediate shaft 5, and the rotation is transmitted by the clutch member 6. As the piston 7A reciprocates by the reciprocating bearing 7, the pressure of the air pressure in the air chamber 8 varies, and the striker 9 is struck by the pressure variation. The striker 9 strikes the intermediate piece 10 and the intermediate piece 10 strikes a tip tool (not shown).

  As described above, in the operation of FIG. 1, rotation and impact are performed on the tip tool.

  FIG. 2 shows an operation performed only on the tip tool for rotation.

  FIG. 2 shows a state in which the operation member 12 of the hammer drill showing one embodiment of the present invention in FIG. 1 is rotated 90 degrees. In this case, the intermediate shaft 5 and the non-rotatable clutch member 6 are moved in the direction opposite to the motor 1 against the biasing force of the spring 5B, which is an elastic body. This is because the contact portion 12A of the switching member 12 is eccentric with respect to the rotation axis L of the switching member 12, and the contact portion 6B1 of the second member 6B of the clutch member 6 is rotated by 90 degrees (see FIG. 5) By contacting with. For this reason, the clutch member teeth 6A1 and the reciprocating bearing teeth 7A are not engaged. Thus, since the clutch member 6 and the reciprocating bearing 7 are not engaged, the piston 7A does not reciprocate. Therefore, the tip tool is not hit.

  The clutch member 6 is configured by the intermediate shaft 5, a first member 6 </ b> A that cannot rotate, and a second member 6 </ b> B that extends in the axial direction of the intermediate shaft that can rotate relative to the first member 6 </ b> A. In addition, relative rotation occurs between the first member 6A and the second member 6B. Therefore, all the rotation of the intermediate shaft 5 is not transmitted to the second member 6B. For this reason, the friction between 12 A of contact parts and 6 A of contact parts can be made small. The third member 6C suppresses the movement of the second member 6B toward the counter-motor 1 in the vicinity of the contact portion of the clutch member 6 with the spring 5B. A slight gap is opened between the second member 6B and the third member 6C, and the axial direction of the intermediate shaft 5 when the second member 6B rotates relative to the first member 6A. It is possible to move to.

  As described above, the clutch member 6 includes the intermediate shaft 5, the first member 6A that cannot rotate, and the second member 6B that can rotate relative to the first member 6A. An increase in the axial length can be suppressed, and a compact hammer drill can be provided. Moreover, since a clutch member is comprised by the 1st member and the 2nd member, it can suppress that a number of parts increases.

  The operation of the hammer drill according to the second embodiment of the present invention will be described with reference to FIGS. Lubricating oil is sealed inside the gear housing 2B, and as shown in FIG. 6, the lubricating oil can be supplied to the first member through the four holes 6B2 of the second member. . For this reason, lubricating oil is supplied when the first member 6A rotates relative to the second member 6B. As shown in FIGS. 7 and 8, four grooves 18B3 are provided on the inner peripheral surface of the second member 6B that contacts the first member 6A. It extends in the axial direction. Further, the groove 18B3 is connected to the hole 6B2. Therefore, the lubricating oil supplied to the hole 6B2 can be easily supplied during the relative rotation of the first member 6B with respect to the first member 6A. In addition, since the 2nd member 6B is provided so that it may extend in the axial direction of the intermediate shaft 5, the hole part 6B2 can be provided.

  As described above, by providing the hole 6B2 in the second member 6B, lubricating oil is supplied between the outer peripheral surface of the first member 6A and the inner peripheral surface of the second member 6B through the hole 6B2. Therefore, the slidability between the first member 6A and the second member 6B can be increased.

  FIG. 9 shows the clutch member 6 of the hammer drill according to the third embodiment. Since the bearing 6D which is a sliding member is provided between the second member 6B and the first member 6A, the slidability can be further improved.

  In the hammer drill according to the embodiment of the present invention, the power is supplied through the power cord 4. However, the same effect as the present invention can be obtained even when the power is supplied by a rechargeable battery that can be repeatedly charged. It can be played.

  In addition, in the hammer drill of the embodiment of the present invention, the hammer and rotation can be transmitted to the tip tool, or only the rotation can be transmitted, but only the hammer can be transmitted to the tip tool. Even a hammer drill can achieve the effects of the present invention.

  In the hammer drill according to the embodiment of the present invention, the striking and rotation can be transmitted to the tip tool, or only the rotation can be transmitted. However, the striking and rotation can be transmitted to the tip tool, and only the rotation can be transmitted. Even if it is the structure which can transmit only a blow, the effect of this invention can be show | played.

The principal part section front view showing one embodiment of the hammer drill of the present invention 1 is a partially enlarged front view of a cross-section of the main part of FIG. The front view which shows the operation member which comprises one Embodiment of the hammer drill of this invention FIG. 3 is a plan view of the operation member shown in FIG. Sectional front view of a clutch member constituting one embodiment of the hammer drill of the present invention Sectional front view of a clutch member constituting a second embodiment of the hammer drill of the present invention The right view of the 2nd member which comprises the clutch member shown in FIG. Sectional front view of the 2nd member which comprises the clutch member shown in FIG. Sectional front view of the clutch member constituting the third embodiment of the hammer drill of the present invention

Explanation of symbols

1 is a motor, 2 is a housing, 3 is a switch, 4 is a power cord, 5 is an intermediate shaft, 6 is a clutch member, 7 is a reciprocating bearing, 8 is an air chamber, 9 is a striker, 10 is an intermediate, 11 is a cylinder, 12 is a switching member, 6A is a first member, 6B is a second member, and 6D is a bearing.

Claims (3)

A motor,
An intermediate shaft that receives and rotates the rotation of the motor;
A reciprocating motion conversion mechanism provided rotatably on the intermediate shaft and capable of converting the rotation of the intermediate shaft into a reciprocating motion of a piston;
A clutch member substantially fixed on the intermediate shaft and capable of turning on or off transmission of rotation of the intermediate shaft to the reciprocating motion conversion mechanism;
A striker to be struck by the reciprocating motion of the piston;
A tip tool struck through the striker;
A hammer drill having a switching member capable of switching transmission of rotation on or off by the clutch member,
The clutch member has a first member fixed on the intermediate shaft and an inner peripheral surface covering a part of the outer peripheral surface of the first member, and slides on the outer peripheral surface and the inner peripheral surface. A second member that is rotatable about the axis of the intermediate shaft as a rotation center with respect to the first member as a surface;
The hammer drill characterized in that the switching member is capable of contacting the second member.   The hammer drill according to claim 1, wherein a sliding member is provided between the outer peripheral surface and the inner peripheral surface. The second member extends in the axial direction of the intermediate shaft;
The second member is provided with a hole for exposing the outer peripheral surface of the first member,
The hammer drill according to claim 1 or 2, wherein lubricating oil can be supplied between the outer peripheral surface and the inner peripheral surface by the hole.

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