US2430909A - Buffing machine - Google Patents

Description

Nov. 18,1947. G. CASTALD] 2,430,909,

BUFFING MACHINE Filed May 28, 1945 2 Sheets-Sheei 1 1n ven tor Gaefano asfa/d/ Nqv. 18, 1947. G. CASTALDI BUFFING MACHINE Filed May 28, 1945 2 Sheets-Sheet 2 [nven tor Gaefano G'asfa/da Fatented Nov. 18, 1947 BUFFING MACHINE Gaetano Castaldi, Brooklyn, N. Y., assignor to United Shoe Machinery Corporatiomfleming ton, N. J., a corporation of New Jersey Application May 28, 1945, Serial No. 596,121

1 Claim.

This invention relates to buffing machines and is herein illustrated and described as embodied in a bu-r'fing machine of the type disclosed in United States Letters Patent No. 84=9,338, granted April 2, 1907, on an application filed in the name of Andrew W. Rogers. The buffing element in machines of this type consists of an abrasive disk secured over a circular inflated rubber pad. While the pad yields readily to conform to the ordinary irregularities of surface contour such as occur on the articles to be treated, for example, shoes, it nevertheless is incapable, while under normal operating pressure, of reaching into such sharply angular portions of shoe surfaces as the junction of the heel breast with the shank of the shoe.

It is an object of the present invention to provide a machine of the inflated pad type wherein the pad may be rendered capable of operating upon surface irregularities which cannot be reached by the tool in the course of normal operation. This result, in accordance with a feature of the invention, is obtained by reducing the air pressure within the pad to render the too] more flexible.

In the machine illustrated herein a valve, arranged for easy manipulation by the operator, is provided for releasing air from a passageway through which air is supplied to inflate the tool, such release of air serving to lower the pressure within the tool. Asshown herein, the valve is operated by a treadle, to enable it to be opened and closed instantly without requiring the operator to lay down the work which he presents by hand to the machine.

These and other features of the invention will appear more fully from the following detailed description when read in connection with the accompanying drawings and will be pointed out in the appended claim.

In the drawings,

Fig. 1 is an angular view of an illustrative machine embodying the invention;

Fig. 2 is a side elevation, partly in section, of a valve mechanism of the machine; and.

Fig. 3 is a horizontal sectional view showing an air supply passage to the valve mechanism.

The operating instrumentality of the illustrated machine is a buffing tool it of the Nauinkeag type comprising an inflated rubber diskshaped pad having secured over its working face a suitably shaped cover of sandpaper, emery cloth, or similar abrasive material. The tool it is carried upon the lower end of a spindle 52 which rotates in bearings i l, and it is driven from any suitable source of power by a belt it running around a pulley is secured upon the spindle l2.

The-supporting structure of the machine comprises a frame 23 which supports a'bracket 22' in i which are secured the bearings l i.

For supplying air under pressure to the tool it the illustrated machine is provided with a reciprocating airpump housed in a portion 2d of the frame 20 and arranged to supply air slowly through a small orifice to an air chamber 26 carried by the frame Zii A relief valve 28' serves. to. prevent the pressure within the chamber 25 from rising above a predetermined level. Air from the.

chamber 25 is. conductedthrough suitable ducts, to a head 39 on the bracket 22 and thence into the upper end of the spindle 12. The air chamber 26; togetherwith the ducts leading to. the too-l, is. considered a part of the passageway or conduit through which air is supplied from the pump.

The machine, as so far described, is substantially like that, disclosed in the above-mentioned Letters, Patent: No. 849,338; except for the fac that the machine disclosed in the patent has two buffingytools, whereas the machine disclosed in the present application has only one bufilng; tool and is provided with a valve mechanism not disclosed in'the patent. The arrangement for supplying air-under pressure to the bufiing too} of the machine illustrated. herein is substantially like that disclosed in United StatesLetters PatentNo. 901,933, granted October 20, 1908, upon the application of Sherman W. Ladd'.

Secured to and extending from the left-hand side of the air chamber 26 is a hollow bracket 32 which supports a horizontal conduit 35 (Fig. 2). Secured upon the outer end of the conduit 34 is a bracket 36 which carries an upper bushing 38 and a lower bushing Ml. Slidably mounted for heightwise movement in the bushings 3B and 4c is a valve stem 42 having a frusto-conical upper end upon which is secured a cushion of leather, rubber, or like material to form a valve M. The valve 54 engages a complementally formed port opening in a sleeve it carried in a head 48 of the bracket 36.

The bracket 32, as already mentioned, is hollow, having an interior air passage 59 which communicates at one end directly with the interior of the air chamber 26. The opposite end of the air passage 26 communicates through a duct 52 with a duct 5 in the conduit 34 and thence through a duct 56 in the head 48 to the valve port. The passage of air to the valve port may be controlled manually by a valve 58 in the duct 52.

The valv 44 is normally maintained in its upper, closed position by a coil compression spring -89 surrounding the valve stem 42 and having its lower end bearing against; the top of the bushing 40. The upper end of the spring 60 bears against a collar 62 secured upon the valve stem at, and the spring is stifl enough to hold the valve closed against any pressure that would be employed to inflate the tool l 0. A chain 89 connects the lower end of the valve stem 42 to a treadle 66.

In the operation of the machine, the shoe bottom is presented against the under surface of the buffing tool [9. The major portion of the shoe bottom will normally be buffed by the tool I 0 while inflated to a pressure suitable to speedy operation, such pressure being determined by the relief valve 28. However, to enable the tool IE! to reach into the re-entrant angle formed by the shank and the heel breast, or to reach into any unusual depressions in the shoe bottom, the pressure within the tool is relieved to reduce the resistance of the tool to deformation by pressure of the shoe against it. Such variation of the resistance of the tool to deformation is readily accomplished without requiring the operator to release his grasp upon the shoe, by depression of the treadle 66. Such depression opens the valve 44 and permits air to escape from the port into the atmosphere, suddenly lowering the pressure of air within the chamber 26. The tool 19 is thus partially deflated and the extent of the deflation depends upon the length of time during which the valve 34 is held open. The operator is therefor able instantly to control the pressure of the air within the tool [0 in accordance with his needs at any particular stage of the operation, and he can do this without having to shift his balance or release the grasp of either hand from the shoe. The time required for deflating and inflating the tool by the treadle valve is so slight that the entire operation on the shoe bottom can, in effect, be performed continuously. The use of this device has been found, by trial, to increase the output of work considerably.

The present invention can be applied to existing machines of the type disclosed in the patent to Rogers, above mentioned, by removing the tool A of the Rogers machine, and replacing the spindle 2d of the Rogers machine with the .valve stem 42 disclosed herein. The fitting of the valve 46, and the installation of the treadle mechanism, including the spring 88, require but a minimum of trouble and expense. While the machine as thus modified has but one tool instead of two tools of diflerent characteristics, that one too], because of its treadle controlled valve, can be made to do the work of both tools of the original machine in a single operation without requiring the operator to change his position or to move the shoe away from the tool; and it can also reach into surface irregularities of the work piece which are inaccessible to either tool of the original machine. There are now in operation a number of the Rogers machines which can thus be modified with only slight changes.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

A machine for bufling shoe bottoms, having, in combination, an inflatable bufling tool and means for instantly varying the resistance of the tool to deformation without interruption of the buffing operation, said means comprising a conduit for conducting air under pressure to said buffing tool suitable for the buffing of the major portion of the shoe bottom, a Valve through which air pressure can quickly be decreased in said conduit, a foot treadle, and treadle connections through which the valve can readily be opened by operating the foot treadle during the buiflng operation to render the tool, by sudden relief of pressure, sufficiently soft and conformable to surface irregularities of the work piece to en able it to buff portions of the shoe bottom which otherwise would be inaccessible to it, thereby enabling the operator to buff the entire shoe bottom in a single continuous operation without releasing his grasp of the shoe by either hand.

GAETANO CASTALDI.

REFERENCES CITED The following references of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,377,588 Sunnen June 5, 1945 849,338 Rogers Apr. 2, 1907 1,656,182 Enna Jan. 17, 1928 1,642,201 Halleck Sept. 13, 1927 1,679,125 Wineman July 31, 1928 1,820,208 Wineman Aug. 25, 1931 2,063,969 Wineman Dec. 15, 1936

Images