US1245603A - Vibrator. - Google Patents

Description

W. LEWIS.

VIBRATOR;

APPLICATION FILED JUNE 10, l9l5- 1,245,603. Patented Nov. 6, 1917.

F/Q'Ql 5 WE C M M UNITED STATES PATENT OFFICE.

WILFRED LEWIS, 0F HAVERFORD, IENNSYLVANIA, ASSIGNOR TO THE TABOR MANU- FACTURING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

VIBRATOR.

Application filed June 10, 1915. Serial No. 33,349.

To all whom it may concern:

Be it known that I, WILFRED LEWIS, a citizen of the United States of America, residing in Haverford, in the county of Montgomery, State of Pennsylvania, have in-' vented certain new and useful Improvements in Vibrators, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

My present invention relates to fluid pressure devices commonly called vibrators such as are employed in the metal founding art to set a pattern into rapid vibration relative to the mold in the pattern drawing operation, to annul the adhesion, so to speak, between the mold and pattern without-appreciably enlarging the mold.

As practically constructed such vibrators comprise a barrel or cylinder having closed ends which serve as anvils to receive the impact of the hammer formed by a piston working in the cylinder or barrel, and reciprocated with great rapidity by the pressure fluid, ordinarily compressed air, which is alternately admitted to, and permitted to exhaust from the cylinder. The piston or hammer element of such a vibrator moves back and forth with great rapidity, the number of blows struck per minute by the hammer commonly running from eight to twenty thousand, depending on the size and design of the vibrator. In consequence of the force and high frequency of the blows struck by the piston, great difliculty has been experienced in preventing the separable parts of the vibrator from workmg loose in operation, and in securing the strength necessary to prevent rupture of the instrument.

The object of my present invention is to overcome the difiiculties referred to, and this I accomplish by providing a suitable resilient cushion for the metallic parts serving as the anvils receiving the impact of the vibrator piston. The cushion material which I now consider preferable, from a practical standpoint, is compressed cork, though other materials may be employed for this purpose.

The various features of novelty which characterize my invention are pointed .with articularity in the claim annexed to and orming a part of this specification. Fora better understanding of the invention,

Specification of Letters Patent.

out

Patented Nov. 6, 1917.

Figure 1 is a longitudinal section of a vibrator constructed in accordance with the present invention;-and

Fig. 2 is a transverse section taken on the line 22 of Fig. 1.

In the drawings, A represents the barrel or cylinder body of the vibrator, and B the piston working therein. As shown, there are two inlet ports A and A -leading from a common supply passage A to the cylinder space A within the member A. The barrel A is also formed with two sets of exhaust ports. A and A respectively. The piston B, which isbut little shorter in length than the cylinder space, is formed with circumferential grooves B and B which communicate through radial passages. B with a corresponding axial passage B extending into the piston one from each end. Extending across the ends of the cylinder space A are washer like anvil members D and D ordinarily formed like the iston B of tempered steel. These are hel in place by ca members C andC screwed on to the three ed ends of the cylinder body A and forming the ends of the vibrator cylinder proper. As shown, the anvil members D and D are provided on their outer ends with central bosses D which register with central chambers C in the ca members C and G. Surrounding each oss D is a washer like cushion E of a suitable resilient compres-, sible material. As already stated, I consider compressed cork to be superior to any other substance now known to me out of which to form the cushions E. 'Each cushion which filled with lubricating material H or rather felt impregnated with lubricating material. As shown the cap member C is formed with apertured ears C by which the vibrator may be clamped to a pattern or to the pattern plate of amolding machine or the like,

In Fig. 1 the piston B occupies an intermediate neutral position When the vibrator is not in operation the piston B is prevented occupying this intermediate neutral position by a spring F seated at its ends in sockets formed in the washer D and the adjacent end of the piston B. This spring holds the piston B against the anvil member D. When the piston B thus engages the anvil member D, the left hand end of the cylinder space A is connected to the supply passage A through port A channel B and the corresponding radial port B and axial passage B*. At the same time the right hand end of the cylinder space is connected to the exhaust ports A through the groove B and the corresponding radial port B and axial passage B ith the parts in the position just described, thepressure fluid, when supplied to the passage A moves the piston B to the'right, and this moves the groove B out of'register with the port A and into register with the exhaust passage A and at the same time moves the groove 13 out of register with the exhaust passages A and into register with the supply port A whereupon the return movement of the anvil is brought about. This port arrangement of the apparatus and the valve action of the piston causes the piston to reciprocate at high speed so long as the compressed air or other pressure fluid is supplied to the inlet passage A, as will be readily apparent to those skilled in the art, especially as the vibrator shown difi'ers from those which have long been in common use, only in the provisions made for cushioning the anvil. I

I have found by an extended practical use of my invention that the provision of the cushion anvils as described markedly decreases the liability of the parts of the device working loose, and greatly decreases the tendency of the device to rupture under the strains and stresses due to. long continued operation. At the same time, the cushioning of the anvils does not appear to materially impair or change the efi'ectiveness of the vibrator in freeing patterns from molds, or

teases in like uses. My practical experience leads me to believe that the cushions formed of compressed cork or other suitable compressible material, are so long lived as to be practically indestructible when made with sufiiciently large contact surfaces, as they readily may be. I attribute the fact that the compressed cork cushions which I have used do not disintegrate'or char in operation, to the fact, that the cork is porous and the fine pores contain a considerable amount of air which actually perform a major portion of the cushioning function. Ordinarily the vibrators are double acting as shown, but when made single acting a cushioned anvil will obviously be needed at one end only of the cylinder space.

While in accordance with the provisions of the statutes I have illustrated and described herein the best form of my invention now known to me it will be apparent to those skilled in the art that changes may be made in the form of my invention Without departing from its spirit, and that some features of my invention can be used in some cases Without a corresponding use of other features of the invention.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

A vibrator of the kind described comprising a metallic cylinder formed with a cylinder space and with a lubricant receiving cavity smallerin diameter than, and centrally located in one end wall of said space, a reciprocating piston working in said space, a movable metallic anvil membar in said space, said anvil member being formed with a central aperture and with an annular projection on its outer side adjacent, and in register with said cavity and a Washer of compressible resilient material surrounding the annular projection of said anvil member and interposed betweenthe body of the latter and the end wall of said cylinder space.

WILFRED LEWIS.

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