JPH0344437Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a chain for a machining center used in an automatic tool changer of a machine tool or the like.

BACKGROUND ART As shown in FIG. 2, a conventional chain for a machining center includes a pair of outer link plates 1a, 1b and a pair of inner link plates 2a, 2b, which are rotatably connected to each other by a hollow connecting pin 3. A plurality of through holes 6 are connected to each other, and a holder 4 at the rear end of the pull stud of the tool holder is fitted into one end of the hollow connecting pin 3, and the engagement balls 5 are movably held in the radial direction of the holder 4.
A coil spring 7 is inserted into the through hole 6 to urge the engaging ball 5 to protrude toward the inner circumferential surface of the holder 4, and the inner circumference of the hollow connecting pin 3 is inserted into a tool insertion pot. is forming.

When the tool holder is inserted into the insertion pot, the engagement ball engages with the recess at the rear end of the pull stud of the tool holder to hold the tool holder within the insertion pot.

Problems to be Solved by the Invention Therefore, the conventional chain for machining center described above is constructed by assembling the respective parts of the outer link plate, the inner link plate, the hollow connecting pin, and the holder. , there are many disadvantages in terms of production efficiency and maintenance management, such as not only the number of parts increases, but also the number of assembly steps, and if these parts are made of metal, it is necessary to lubricate the sliding surfaces. It had

The present invention aims to eliminate these drawbacks of the conventional examples.

Means for Solving the Problems The present invention is a chain for a machining center in which a link plate, a hollow connecting pin, and a holding fitting are integrally molded from a material such as resin and connected as a unit. A large number of chain units in which an offset link plate portion having an insertion hole at both ends of the pin portion and a pull stud holding portion of the tool holder are integrally molded are alternately and rotatably connected,
The inner circumferential surface of the hollow connecting pin portion is formed on the tool pot surface into which the tool holder is fitted, and the engaging ball that engages in the rear end recess of the pull stud of the tool holder is formed in the radial through hole of the hollow connecting pin portion. This is a chain for a machining center, in which the pin part is loosely inserted with the pin part protruding from the inner circumferential surface thereof.

Operation Expand the offset link plate portion of the chain unit, and insert both ends of the hollow connecting pin portion of the next chain unit to be connected to this unit into the pin both end insertion holes of the expanded link plate portion. Since both units are rotatably connected and the link plate portions of each unit have an offset shape, a large number of chain units of the same shape are connected in the same manner to form a chain for a machining center. , Retaining rings are fitted to the outer peripheral surfaces of both ends of the hollow connecting pin part fitted into the pin part both end insertion holes of the link plate part, so that the link plate part can freely rotate on both ends of the connecting pin part. Hold position.

When the tool holder is inserted from the rear end into the tool pot formed by the inner circumferential surface of the hollow connecting pin part, the engagement ball engages in the recess formed at the rear end of the tool holder and is elastically held. The tool holder is inserted and held within the tool pot.

Further, when the holder is pulled out from the tool pot, the engagement balls are retracted from the inner peripheral surface of the tool pot against the biasing force of the coil spring, so that the holder can be easily pulled out.

Embodiment FIG. 1 is a partial cross-sectional plan view of a main part of a chain for a machining center, and the chain unit 11 has a pair of link plate parts 12, 12 having offset parts 12a, 12b, and a hollow connecting pin part 13. The offset link plate portions 12, 12 have hollow connecting pin portions 1,
An insertion hole 12b for rotatably inserting both ends of the hollow connecting pin portion 13 is provided through the hole 12b, and the inner peripheral surface of the hollow connecting pin portion 13 is formed into a tool pot surface 14 having a tapered fitting surface of a tool holder (not shown). In addition, the hollow connecting pin portion 13 is provided with a plurality of through holes 15 in the radial direction, and in the through holes 15, an engaging ball 16 is inserted into a recess formed at the rear end of the pull stud of the tool holder. is held in a loose state and is biased by a coil spring 17 to protrude in the direction of engaging in a recess formed at the rear end of the pull stud.

Note that a steel bushing for reinforcing the inner peripheral surface may be fitted into the through hole 15.

The coil spring 17 is held in the through hole 1 by a spring retaining ring member 19 fitted in an annular groove 18 recessed in the outer periphery of the hollow connecting pin portion 13.
It is suppressed and held within 5.

Therefore, the opposing distance between the pair of offset link plate parts 12, 12 of the chain unit 11 is expanded by external force, and the next chain unit connected thereto is inserted into the insertion holes 12b, 12b of the link plate part. Both ends of the hollow connecting pin portion are rotatably fitted, and the hollow connecting pin portion 13 is secured by the retaining ring 20.
is sandwiched and held between the link plate parts 12, 12.

Since the offset portions 12a, 12a of the link plate portions 12, 12 form a recess for receiving the end of the link plate portion of the next chain unit, each chain unit 1 is integrally molded in the same shape. It is also possible to connect a large number of them to form a chain.

In addition, a radial through hole 15 is directly provided in the thick retaining portion of the hollow connecting pin portion 13 to urge the engagement ball 16 to protrude toward the inner circumferential surface, and the inner circumferential surface is used as a tool pot into which a tool holder is inserted. Therefore, when the tool holder is inserted into the tool pot from the rear end, the engagement ball 16 is retracted by the rear end of the tool holder against the biasing force of the coil spring 17, and the rear end of the tool holder is inserted into the tool pot. The tool holder is inserted into the hollow connecting pin portion 13 by protruding and engaging in the recess formed at the rear end portion.
When the tool holder is pulled out, the engaging balls are pushed up against the force and retracted into the through hole 15 by an external force in the pulling direction, so that the tool holder can be pulled out easily.

Effects of the invention The present invention constitutes a chain for a machining center by rotatably connecting a number of chain units of the same shape, which are integrally molded with a link plate portion having an offset shape, a hollow connecting pin portion, and a pull stud holding portion. This greatly reduces the number of parts, making processing and assembly easier, significantly reducing the number of man-hours, and greatly increasing production efficiency.
Production costs are also reduced, and resin can be used as an integral molding material, so when the chain unit is made of resin, it is not only lightweight, but also can significantly reduce noise. Its good lubricity makes it possible to use it without lubrication, making maintenance management extremely easy, and has great practical effects.

[Brief explanation of drawings]

Figure 1 is a plan view of the main parts of the present invention with a partial cross section;
FIG. 2 is a partial cross-sectional plan view of the main part of a conventional example. 11... Integrally molded chain unit, 1
2... Link plate portion, 12a... Offset portion, 12b... Insertion holes at both ends of the hollow connecting pin portion, 13... Hollow connecting pin portion, 14... Tool pot surface, 15... Through hole, 16 ...Engagement ball, 1
7...Coil spring, 19...Spring retainer ring member.

Claims (1)

[Scope of utility model registration request] A large number of chain units, each of which is integrally formed with a hollow connecting pin portion, an offset link plate portion having insertion holes at both ends of the pin portion, and a pull stud holding portion of the tool holder, are connected rotatably to each other, and the hollow connecting pin The inner circumferential surface of the part is formed as a tool pot surface into which the tool holder is fitted, and the engagement ball that engages in the rear end recess of the pull stud of the tool holder is inserted into the radial through hole of the hollow connecting pin part. A chain for machining centers that is loosely loaded with a protruding bias on the inner peripheral surface of the part.