Bar loader

Details Bar loader Bar loader

1997-06-16

2001-02-06

Tsai, Henry W. H. (Department: 3722)

Turning

Lathe

With work feeder or remover

C082S125000, C082S126000, C414S015000

Reexamination Certificate

active

06182543

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention relates to an automatic bar loader which feeds a bar to a bar machining apparatus such as a NC lathe or the like.
DESCRIPTION OF THE PRIOR ART
An automatic bar loader for feeding an elongated bar automatically to a bar machining apparatus such as a NC lathe or the like has been known. Such a bar machining apparatus machines the leading end of the bar. The bar loader has a guide rail which extends straight toward the bar machining apparatus and the bar to be machined is fed to the bar machining apparatus therein. A trailing end of the bar is held by a finger chuck that is provided at a leading end of the feeding rod. A leading end of the bar is held by a collet chuck provided in the bar machining apparatus. The bar is fed to the bar machining apparatus by forward and rearward movement of the feeding rod within the guide rail. The guide rail has a channel-like shape and has an elongated opening oriented upwardly over its length. After a bite provided in the bar machining apparatus separates the last product from the bar, a remainder bar piece is discharged from the apparatus. Then, a new bar is taken out of a stock rack provided next to the guide rail and is fed into the guide rail through the opening.
As stated above, the bar is held by the finger chuck at the trailing end thereof within the guide rail and it is held by the collet chuck of the bar machining apparatus at the leading end thereof. Therefore, the middle portion thereof deflects because of its own weight, especially when the bar to be machined is slender. Due to the deflection, or due to the shape of the bar that is originally bent, the peripheral surface of the bar makes contact with an inner surface of the guide rail. During machining operations, the bar is rotated at a high speed within the guide rail. Therefore, contact between the bar and the inner surface of the guide rail causes vibration and noise.
Conventionally, a so-called “oil type” bar loader which is constructed in such a way to decrease the vibration and noise during machining operations has been known. In this conventional apparatus, the vibration of the bar is suppressed by preventing the bar from making contact with the guide rail. That is, in this type of bar loader, a new bar is supplied to the guide rail through the elongated opening and the elongated opening is sealingly closed by a lid. Then, the space between the bar and the inner surface of the guide rail is filled with oil. The bar is positioned at the center of the guide rail by a fluid mechanical centripetal action caused by the rotation of the bar in the oil.
However, in the above oil-type bar loader, it is necessary to have a highly sealed structure so that the oil does not leak outside of the guide rail during the rotation of the bar. Especially, in the type of bar loaders which control the movement of the feeding rod by changing the oil pressure, it must be constructed so that the pressurized oil does not leak. Such a sealed structure needs accurately formed parts which are sealingly engageable with each other, and also an intricate mechanism for opening and closing the lid. Therefore, the complex structure of the apparatus causes manufacturing costs to increase.
Further, to meet the demand in the industry requiring unmanned operations, it is desirable that the bar loader Is constructed to be automatically operable.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a bar loader having a simple structure which can solve the vibration and noise problem of the bar.
It is, a further object of the present invention to provide an unmanned bar loader which can solve the vibration and noise problem of the bar.
The present invention attains the above objects of the present invention based on an idea that is completely different from the conventional one which utilizes a complex structure with a guide rail filled with oil in which the bar is positioned at the center of the guide rail by a fluid mechanical centripetal action when the bar is rotated. The inventor of the present invention realized that the cause of the noise and vibration was that when the bar rotates, it rolls upwardly along the inner surface of the guide rail due to the friction generated when the inner surface of the guide rail comes in contact with the peripheral surface of the bar. When the bar reaches to a certain point, it falls due to its weight and hits the bottom surface of the guide rail. The repetition of this action causes the vibration and the noise. The present invention solves the objects by a bar loader having a simple structure. Further more, the present invention achieves the object by an automatically operable apparatus to meet the demand in the industry requiring unmanned operations.
A bar loader according to the present invention comprises: a guide rail for feeding a bar to a bar machining apparatus which extends straight toward the bar machining apparatus and has an opening for receiving a new bar, said opening being oriented upwardly and extending longitudinally along the guide rail; and oil feeding means for feeding oil into said guide rail, an amount of said oil being enough to coat a peripheral surface of the bar.
In a preferred aspect of the present invention, the bar loader further comprises a lid for covering said opening.
In a further preferred aspect of the present invention, the bar loader further comprises: a stock rack provided parallel to and by the side of said guide rail, said stock rack holding a plurality of bars to be fed into said guide rail parallel to said opening; an index disk arranged substantially perpendicular to said opening of said guide rail and said bars on said stock rack, said index disk having at least one pocket at its circumference for receiving one of said bars held on said stock rack, and said index disk being rotatable between a first angular position for receiving said bar into said pocket and a second angular position for feeding said bar received in said pocket into said guide rail; and driving means for rotating said index disk, and wherein said lid is moved by said driving means so that said opening of said guide rail is opened when said index disk is in said second angular position.
In a still further preferred aspect of the present invention, the bar loader further comprises: a stock rack provided parallel to and by the side of said guide rail, said stock rack holding a plurality of bars to be fed to said guide rail; and a bar taking out mechanism for taking out a bar from said stock rack and feeding said bar into said guide rail; and a cover for preventing oil scattering which surrounds said guide rail, said stock rack and said bar taking out mechanism.
In a still further preferred aspect of the present invention, said oil feeding means having an oil outlet for feeding oil into said guide rail, and the bar loader further comprises: detecting means for detecting a location of said feeding rod within said guide rail; and means for controlling to feed the oil from said oil outlet into said guide rail when it determines that said feeding rod is located behind said oil feeding outlet based on the detected result by said detecting means.
In a still further preferred aspect of the present invention, said oil feeding means has a plurality of oil feeding outlets provided along said guide rail at a distance from each other, and said controlling means determines a middle portion of said bar based on the detected result by said detecting means and feeds the oil into said guide rail from said oil feeding outlet located closer to said middle portion of said bar.
In a still further preferred aspect of the present invention, the bar loader further comprises an oil absorber provided on the forward side of said guide rail, said oil absorber being in contact with a peripheral surface of said bar fed toward said bar machining apparatus.
The above and other objects and features of the present invention will become apparent from the following detailed description, taken in conjunction with the ac

Affiliated with

Also associated with

Rating

Bar loader does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Bar loader, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bar loader will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2576762