JPH0453846Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a tool attachment/detachment device for a small cutting tool used for cutting metals, resins, etc.

Conventional technology Conventionally, in a small cutting tool, a chuck for rotating the tool is positioned in an axial direction different from the main drive shaft of the electric motor, and is biased in the tightening direction by the pressing force of a spring inside the chuck case. When attaching and detaching a tool to a small cutting tool, there are methods in which the operator uses a special tool to open and close the chuck to attach and detach the cutting tool, and methods in which the attaching and detaching device protrudes outside the casing of the cutting tool. All of these attachment/detachment devices require time and effort to attach/detach the cutting tool. To compensate for this drawback, there is an attachment/detachment device in which a cam is installed in the head of the driven shaft of the cutting tool, and the cam allows the chuck to move forward and backward, but this device has many parts and is This method requires a large amount of space, complicates the structure of the device, and makes the cutting tool heavy, resulting in poor workability.

Problems to be Solved by the Invention The present invention attempts to solve the above-mentioned problems by simplifying the structure of the device without taking up space in the head section on the driven shaft as in the conventional case. The purpose of this invention is to reduce the weight and size of a cutting tool, and to enable reliable and easy attachment and detachment of the tool when attaching and detaching the tool to and from the cutting tool.

Means for solving the problems In order to solve the problems mentioned above, the present invention
In a small cutting tool, a chuck for rotating the cutting tool located in an axial direction different from the main drive shaft of the electric motor is biased in the tightening direction by the pressing force of the tightening spring inside the chuck case. A set ring is screwed so that it can move forward and backward, and a swing arm that is biased against the set ring is located on the inner periphery of this set ring, and this swing arm can be pushed inward or restored as the set ring moves back and forth. In addition, the inner surface of the swing arm is located facing the end surface in the extending direction of the chuck, and when the swing arm is pressed as the setting ring advances and retreats,
The chuck can be pressed in the direction of releasing the fastening.

Function Since the present invention is constructed as described above, in order to tighten the tool to a small cutting tool, the setting ring screwed onto the outer periphery of the main body casing is rotated, and the setting ring is rotated in the direction toward the tip of the main shaft of the electric motor. When the chuck is moved to , the inner surface of the settling ring abuts the swing arm and presses the swing arm inward, forcing one surface of the swing arm to press against the end surface in the extending direction of the chuck. If this pressing force becomes larger than the force of the fastening spring that presses the chuck in the fastening direction inside the chuck case, the chuck will slide inside the chuck case in the unfastening direction, and a tool can be attached to and removed from the chuck. state.

Furthermore, if the set ring is rotated in the opposite direction to the above and moved toward the proximal end of the main drive shaft, the pressing force on the swing arm that was pressed against the inner surface of the set ring is released, and the swing arm Restore movement in the outward direction. By this restoring movement of the swing arm, the swing arm releases the pressure applied to the chuck against the restoring force of the fastening spring, and the chuck slides in the chuck case in the fastening direction due to the restoring force of the fastening spring. The tool can be tightened and fixed.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a main drive shaft, which is connected to an electric motor and has a main drive bevel gear 2 connected and fixed to its tip.
A chuck case 4 of the tool 3 is formed to be located in a different axial direction from the main drive shaft 1, and a driven bevel gear 5 is provided on the outer circumference of the chuck case 4. The rotation is transmitted to the chuck case 4. A chuck 8 is inserted into the chuck case 4 in the axial direction from the distal end thereof with a split groove 6 and a fastening tapered surface 7 on the outer periphery of the distal end, and the tool 3 can be inserted into the chuck 8. It is said that Further, a connecting member 10 is screwed and fixed to the opposite side of the chuck 8 from the side where the tool 3 is inserted, and an annular collar 1 provided at the outer end of the connecting member 10 is connected.
A fastening spring 12 is interposed between the chuck case 4 and the chuck 8, and the restoring force of the fastening spring 12 pulls the chuck 8 into the chuck case 4, and the tapered fastening surface 7
The chuck 8 is configured to generate a tightening force as the chuck 8 is inserted into the chuck case 4. Further, the chuck case 4 is fixed inside a casing 14 via a bearing 13. Further, a main body casing 16 is installed on the outer periphery of the main drive shaft 1 via a bearing 15, and this main body casing 16
A settling ring 17 is screwed onto the outer periphery of the set ring so as to be movable in the axial direction. An abutting tapered surface 18 is formed on the inner surface of the settling ring 17 in the moving direction, and this abutting tapered surface 18 is connected to the outer periphery of the swing arm 20.
It is formed in abutment against the pressure receiving tapered surface 21. The fixing part 22 bent at one end of the swing arm 20 is fixed to the engagement recess 23 of the main body casing 16 located on the inner periphery of the setting ring 17, and the abutting inner surface 24 in the distal direction is fixed to the engaging recess 23 of the chuck 8. While facing the outer end 25 of the connecting member 10 provided in the axial direction, the swing arm 20 is moved by the pressing force of the return spring 27 interposed between the swing arm 20 and the main body casing 16. It is normally pressed in a direction that does not contact the outer end 25 of the connecting member 10.

In the structure as described above, in order to fasten the tool 3 to the cutting tool 26, the main body casing 1 is
When the set ring 17 screwed onto the outer periphery of the swing arm 6 is rotated and moved toward the tip of the drive shaft 1, the abutting tapered surface 18 on the inner surface of the set ring 17 abuts against the press-receiving tapered surface 21 of the swing arm 20, causing the swing arm to swing. The arm 20 is returned and pressed in the direction of the connecting member 10 against the restoring force of the spring 27. This swing arm 2
The swing arm 20 presses and urges the outer end 25 of the connecting member 10 by a pressure of 0, and the chuck 8 is pressed and slid in the direction of protrusion from inside the chuck case 4 against the restoring force of the fastening spring 12. The tightening tapered surface 7 of the chuck 8 is moved in the protruding direction from the chuck case 4, the chuck 8 is expanded, and the tool 3 can be attached to and removed from the chuck 8.

Also, if the set ring 17 is rotated in the opposite direction to the above and moved toward the proximal end of the main drive shaft 1, the abutting tapered surface 18 releases the pressure on the pressure receiving tapered surface 21, and swings. Since the arm 20 returns to its original position due to the restoring force of the return spring 27, the pressure of the swing arm 20 on the connecting member 10 is released. By this restoring movement of the swing arm 20, the connecting member 10 slides the chuck 8 into the chuck case 4 by the restoring force of the fastening spring 12, and draws the fastening tapered surface 7 of the chuck 8 into the chuck case 4. The expanded chuck 8 can be contracted to tighten and fix the tool 3 to the cutting tool 26.

Furthermore, if the set ring 17 is formed into an elongated shape and extended in the proximal direction, the set ring 17 can be rotated from the proximal direction which is further away from the chuck 8, and the tool 3 can be moved to the cutting tool 2 by remote control. It can be attached and detached.

Effects of the invention Since the invention is configured as described above, when attaching or detaching the tool to the cutting tool, the tool can be attached or detached reliably and easily by rotating the settling ring screwed onto the main body casing. do. Also, since the head section on the driven shaft does not take up much space, the structure of the device can be simplified, and the cutting tool can be made simpler, lighter, and more compact, making it possible to perform cutting operations at low cost and with good workability. do.

In addition, unlike when using a cam, etc., there is no restriction on the mounting position of the operation part that tightens and releases the chuck, and by adjusting the length of the swing arm, the setting ring can be installed in any location. It is possible to improve workability and design freedom.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially cutaway sectional view. 1... Main drive shaft, 3... Tool, 4... Chuck case, 8... Chuck, 12... Fastening spring, 16
...Body casing, 17...Settling, 2
0...Swing arm.

Claims (1)

[Scope of utility model registration request] In a small cutting tool, a chuck for positioning and rotating the tool in an axial direction different from the main drive shaft of the electric motor is biased in the tightening direction by the pressing force of the tightening spring inside the chuck case. A set ring is screwed so that it can move forward and backward, and a swing arm that is biased against the set ring is located on the inner periphery of this set ring, so that the swing arm can be pushed inward or restored as the set ring moves back and forth. In addition, the inner surface of the swing arm is positioned so as to face the end surface in the extending direction of the chuck, so that the chuck can be pressed in the direction of unfastening when the swing arm is pressed as the setting ring advances and retreats. Cutting tool fastening device.