JPH04125510U - hammer drill - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a simple and compact connection structure between a piston for applying a hammer action to a tool and a plunger forming a swinging mechanism, and to have no problems in terms of strength. [Structure] An elongated hole is provided at the joint between the striking piston that gives a hammer action to the tool and the swinging mechanism, and the extension of the plunger forming the swinging mechanism is engaged with this elongated hole.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention combines the drill action that rotates the tool, the rotation action that rotates the tool, and the Regarding a hammer drill that can switch between hammer action and hammer action that applies impact force. .

0002

[Conventional technology]

Hammer drills are used as power tools to drill holes in workpieces. . A hammer drill of this type is described, for example, in German Patent No. 3438208. . That is, as shown in FIGS. 5 and 6, the conventional hammer drill uses the rotational force of the motor. is transmitted to the intermediate shaft 30, a swing mechanism 50 is attached to this intermediate shaft 30, and this swing The mechanism 50 causes the piston 36 that applies impact force to the tool to reciprocate. ing. The swinging mechanism 50 includes a swinging bearing provided on the drum 31 at an angle. A plunger 33 extends from the swing bearing 32. A spherical head 34 is provided at the middle portion of the plunger 33, and the spherical head 34 The rod 34 is freely coupled within a coupling portion 37 provided at the rear portion of the piston 36. ing.

0003 The coupling portion 37 has an outer frame 38 that projects rearward from the piston body, and this outer frame A bearing sleeve 39 is mounted within 38 . The upper part of the connecting part 37 has left and right sides. Two guide pins 40, 40 are provided at intervals, and the guide pins 40, The extension part 35 of the plunger 33 is guided between 40 and the extension part 35 and the plunger The engagement with the idle pin 40 prevents the rotation of the piston 36 during use of the hammer drill. I'm trying to prevent it.

0004

[Problem that the idea aims to solve]

However, in order to prevent the piston 36 from rotating, the upper part of the coupling part 37 is are provided with guide pins 40, 40 spaced apart from each other, and a plunger is inserted into the guide pin 40. Since the extension portion 35 of the roller 33 is guided, the guide pin 40 Holes are formed in the rear wall of the piston 36 and the rear wall of the outer frame 38 at the front and rear ends of the guide pin. The pin 40 must be secured to the joint 37. In this way, the guide pin 40 In order to securely fix the front and rear ends of the guide, not only is it necessary to drill holes, but the guide The wall thickness of the outer frame 38 must be increased to some extent for strength reasons to support the pins 40. First, there was a problem in that the overall length of the piston 36 became long. Furthermore, piste in general Since the pin 36 is made of a light alloy, the strength of the joint 37 is not sufficient, and the guide pin There is also a risk that the 40 may come off or be damaged due to the impact at the time of impact.

[0005] In view of this point, the present invention has a compact connecting part at the rear of the piston. At the same time, not only does complicated processing such as drilling become unnecessary, but it also eliminates the need for strength-related problems. The extension part of the plunger can be guided securely and the piston can be prevented from rotating. The purpose is to provide a hammer drill that can be used.

[0006]

[Means to solve the problem]

This invention transmits the rotation of the motor to the impact device via a swing mechanism attached to the intermediate shaft. The impact device is a handle having a striking piston that reciprocates in the axial direction of the drill. In the Mardrill, the rocking mechanism is provided at a joint between the striking piston and the rocking mechanism. The head of the plunger of the structure is freely connected, and the extension of the head of the plunger is connected to the head of the plunger. A guide portion that guides the piston in the axial direction is provided, and the guide portion is shaped in the coupling portion. The piston is constructed with a long hole that prevents the piston from rotating during impact. did.

[0007]

[Effect]

A plug is installed at the joint between the striking piston and the swinging mechanism that swings the striking piston. the head of the plunger is freely coupled, and the extension of the head of the plunger is coupled to the coupling. the extension part of the plunger along the elongated hole. Guide. This not only eliminates the need for complicated processing such as drilling holes. If the wall thickness of the joint can be made thinner and the joint can be constructed more compactly, In addition, it is necessary to prevent damage to the guide part that guides the extension part of the plunger. can be done.

[0008]

【Example】

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the hammer drill M of the present invention has a pistol-shaped casing 1. , this casing 1 is provided with a main handle 2 and a front handle 3. The above A motor 4 is provided in the center of the thing 1, and the rotation of this motor 4 is caused by a main shaft 5. The rotation of the main shaft 5 is transmitted to the intermediate shaft 6 via the gear 30. Inside this The intermediate shaft 6 is provided with a switching device 7, and the switching device 7 and the front end of the casing 1 are provided with a switching device 7. A striking piston 12 that constitutes an impact device that acts as a hammer on a tool 13 that is A swing mechanism S for reciprocating in the direction is provided.

[0009] A gear 51 is provided at the front end of the intermediate shaft 6, and this gear 51 rotates the rotating cylinder 52. The tool 13 is provided at the front end of the rotary cylinder 52. child The piston 12 is housed in the rotary cylinder 52, and when the hammer drill M is operated, The rotation of the rotating shaft 6 is always transmitted to the tool 13, and the tool 13 rotates. this tool 13, the switching sleeve 14 of the switching device 7 is The coupling 14a is moved to the right side, and the coupling 14a is moved to the right side. and the coupling 8a of the arm 8. The swing mechanism S is connected to the drum 8. A rocking bearing 9 is provided on the drum 8 at a predetermined angle, and this rocking bearing The plunger 10 projects upward from the ring 9. this plunger 10, as shown in FIG. , this spherical head 20 is freely attached to the coupling part 11 provided at the rear of the piston 12. When the rotation of the intermediate shaft 6 is transmitted to the drum 8, the swing mechanism S When activated, the piston 12 reciprocates in the axial direction of the intermediate shaft 6.

0010 As shown in FIGS. 3 and 4, the coupling portion 11 projects toward the rear of the piston 12. It has an outer frame 23, and a cylindrical bearing sleeve 22 is fixed inside this outer frame 23. . The upper surface of the bearing sleeve 22 is hollowed out in an elliptical shape to form a long hole 24. Ru. This elongated hole 24 is located on the side of the extension portion 21 that projects above the plunger 10. It forms a guide part that guides the wall, and the engagement between this extension part 21 and the inner wall of the elongated hole 24 This prevents the piston 12 from rotating.

[0011] When reciprocating the piston 12, the swinging mechanism S operates. At this time, the extension portion 21 of the plunger 10 swings in the direction of movement of the piston 12. In this way, the guide part that guides the extension part 21 of the plunger is composed of the elongated hole 24. If so, there will be no problem with the strength for guiding the extension part 21, and moreover, as mentioned above, In order to support the guide pin, the wall thickness of the joint is made thicker than necessary in order to support the guide pin as in the conventional method. Not only does it not need to be done, but it also eliminates the need for complicated processing such as drilling holes. . Generally, the piston 12 is generally used to reduce the load on the oscillating bearing. The extension part 21 is made of a light alloy, and when applying an impact force to the piston 12, the extension part 21 is Impact force will also be applied to the guide section. However, with elongated hole 24 like this As long as the guide portion is constructed, there is no problem in terms of strength even if the material is made of a light alloy.

0012

[Effect of the idea]

Since the present invention is constructed as described above, the head of the plunger forming the swinging mechanism is Not only can the guide be ensured, but the connection between the plunger and piston can also be improved. Not only can the total length of the joint be shortened, but the wall thickness can also be made thinner. Moreover, complicated processing such as drilling is unnecessary.

[Submission date] August 7, 1992

[Procedural amendment 1]

[Name of document to be amended] Specification

[Correction target item name] 0001

[Correction method] Change

[Correction details]

0001

[Industrial application field]

The present invention relates to a hammer drill that can switch between a drill action that rotates the tool, a rotation action that rotates the tool, and a hammer action that applies impact force to the tool while rotating the tool.

[Brief explanation of drawings]

FIG. 1 is a cutaway view of essential parts of a hammer drill of the present invention.

FIG. 2 is a sectional view showing a swinging mechanism for connecting an impact device and an intermediate shaft of the hammer drill according to the present invention.

FIG. 3 is a top view of the piston.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a sectional view showing a swing mechanism for coupling a conventional striking device and an intermediate shaft.

FIG. 6 is a plan view of a conventional piston.

[Explanation of symbols]

1...Case 2...Main handle 3...Front handle 4...Motor 5...Main shaft 6...Intermediate shaft 7...Switching device 8...Drums 9...Swing bearing 11...Joining part 21...Extension part 22...Bearing sleeve 23...Outer frame 24...Long hole

Claims (1)

[Scope of utility model registration request] 1. A hammer drill in which rotation of a motor is transmitted to an impact device via a swinging mechanism attached to an intermediate shaft, and the impact device has a percussion piston that reciprocates in the axial direction of the drill, the impact device being connected to the percussion piston. A head of a plunger of the rocking mechanism is freely connected to a joint with the rocking mechanism, and a guide part is provided for guiding an extension of the head of the plunger in the axial direction of the piston, and the guide part A hammer drill comprising an elongated hole formed in the connecting portion to prevent rotation of the piston during impact.