US3633540A

US3633540A - Rotatable fixture with positive retention and lifting means

Info

Publication number: US3633540A
Application number: US5192A
Authority: US
Inventors: Alfred V Bolt; James S Wood
Original assignee: Aluminum Company of America
Current assignee: Howmet Aerospace Inc
Priority date: 1970-01-23
Filing date: 1970-01-23
Publication date: 1972-01-11
Anticipated expiration: 1989-01-11

Abstract

A fixture for positively centering and holding an article in a coating process in which the interior and exterior surfaces of the articles are simultaneously coated while the article is rotated by the fixture. Further, the fixture includes means for lifting the article to allow its easy removal from the fixture. In addition, a structure is provided for masking the inner lip or rim of a pan cover or lid when applying a porcelain coating to the exterior surface of the lid.

Description

United States Patent Inventors Alfred V. Bolt;

999,789 8/1911 ll8/320X James S. Wood, both of Chllhcothe, OhlO 2 07 99 4/1937 134/149 UX 5,192 2,515,359 7/1950 1 18/500 [22] Jan-23,1970 2,655,128 10/1953 118/503 x 5 gi 2 A 3,322,095 5/1966 Hansen m1. 118/318 x S gnee 33:3; z FOREIGN PATENTS 1,277,501 10/1961 France 118/503 2,943 1906 Great Britain. l 18/500 [54] ROTATABLE FIXTURE WITH POSITIVE 468,835 2/1952 Italy l l8/503 EE F L S P TING MEANS Primary Examiner-Morris Kaplan alms rawmg Attorney- Elroy Strickland 52 us. or 118/502,

269 50, 279 l E 51 1111. C1 B05c 11 /14 ABSTRACT A M P0sitive|y centering and hldmg 501 Field of Search 118/500 in a mating which the interim and 3 502 320, 503, 56 5245; 269/50 55 surfaces of the articles are simultaneously coated while the ar- 4152; 5) 123; 294/655. 134/'l49 H ticle is rotated by the fixture. Further, the fixture includes means for lifting the article to allow its easy removal from the References Cited fixture. In addition, a structure is provided for masking the UNITED STATES PATENTS inner lip or rim ofa pan cover or lid when applying a porcelain 689 265 12/190] wieland 118/500 coating to the exterior surface of the lid.

l l n msmw mu 1 1922 31633; 540

SHEEI 1 OF 2 FIG. I.

lllllllllllllll HVVENTORS. ALFHEZJ 5/. BOLT and JflMEiS 1?. W000 BACKGROUND OF THE INVENTION The present invention relates generally to a fixture for holding and rotating an article in a process for coating same, and particularly to a fixture for positively securing and rotating a pan or a cover (lid) in a process in which a ceramic porcelain coating of one or more colors is applied to the interior and exterior surfaces of the pan or cover without removing the pan or cover from the fixture until the process is completed.

In many cases, the process of coating a pan, or cover for same, involves the application of a glossy ceramic porcelain finish on the exterior of the pan or cover, and a dark, porcelain frit coating applied to the interior thereof, the frit coating serving as a substrate for a future Teflon coating. In applying these porcelain coatings, a single pan or cover is usually supported on a fixture which, in turn, is disposed on a conveyor apparatus for travel past stationary spray guns located in spray booths. The guns automatically spray and apply the coatings when the fixture enters the booths.

Heretofore, the exterior and interior surfaces of the pan or cover were coated in separate operations requiring separate spray booths. With the fixtures available in the industry, after the exterior was coated, the pan or cover had to be removed from the fixture, turned over and then replaced on the fixture for coating the interior surface ofthe pan or cover.

A fixture commonly used in the application of porcelain finishes to container exteriors employs two band saw blades tautly strung between four ends of four angularly disposed arms, the other ends of the arms being secured in the hub ofa vertically disposed spindle mounted for rotation about its vertical axis. The blades are strung in a crosswise manner to each other. A center wire is attached to the blades at the point at which they cross and to the spindle hub to pull the center of the blades in a downward direction. This provides a somewhat concave structure to center and support the pan. The teeth of the blades provide a slip resistant edge, but during rotation the teeth are not sufficient to retain the pan in a center position. Thus, with rotation, the pan tends to slip off center, and with the eccentric moment resulting therefrom, the pan can leave the fixture altogether. This has required the use of separate spray booths and operations for coating the exterior and interior of pans since the accuracy of the coating application is substantially diminished with the tendency of the pan to move about on the fixture.

Further, such a structure provides no means for lifting the pan so that it can be conveniently removed from the fixture when the coating processes are completed.

BRIEF SUMMARY OF THE INVENTION Broadly, the present invention provides a fixture which positively centers and retains a pan or cover in a center position on the fixture when it is rotated. This allows accurate application of coatings to the pan or cover so that the exterior and interior surfaces thereof can be simultaneously coated without requiring removal of the pan or cover from the fixture until the process is completed. This is accomplished by using a hollow post or spindle vertically disposed and mounted for rotation about its vertical axis. Adjacent the top of the spindle is rigidly attached a plurality of arms for supporting a pan or cover, the arms radiating outwardly from the spindle. The arms are provided with pin structures for centering and positively engaging the edge ofa pan so that it will not move about or fly off the arms when rotated. For holding and centering a cover, a cylindrical mask is located on the arms, the mask serving further to mask an annular rim portion of the cover from the porcelain applied to the exterior surface of the cover for reasons explained hereinafter. Further, the spindle is provided with a vertically movable post for lifting the cover clear of the arms when it is desired to remove the article from the fixture. This may be done automatically by a cam or other sliding surface disposed in the path of the fixture as it is conveyed past a location or station for removing the article from the fixture.

THE DRAWINGS The invention, along with its advantages and objectives, will be more apparent upon consideration of the following detailed description in connection with the accompanying drawings in which:

FIG. 1 is a vertical section of a pan and cover supporting fixture constructed in accordance with the principles of the invention, a cover being supported on the fixture as shown;

FIG. 2 is a top view of the fixture ofFIG. 1;

FIG. 3 is a top plan view of a means for engaging and lifting the cover located on the fixture of FIG. 1; and

FIG. 4 is a partial side elevation of the fixture of FIG. I employed to support a pan.

PREFERRED EMBODIMENT Specifically, in FIG. I there is shown a fixture 10 for positively holding and spinning an article 12, the article shown being a shell or cover for a container, such as a pan or pot used for cooking purposes, though the invention is not limited thereto.

The fixture 10 comprises essentially a vertically disposed spindle structure generally designated 14, three horizontally disposed arms 16 (FIG. 2) attached to an upper tubular structure or post 18 (forming a part of the spindle) and radiating outwardly therefrom, and a solid center post or rod 20 slidably mounted within the spindle and the tubular structure 18.

The arms 16 are rigidly attached to the tubular post 18, for example by welding the arms to the post after the inwardly directed end of each arm is disposed in an opening 22 provided in the wall of the post. To further secure and support each arm, a brace 24 is provided between each arm and the post and welded thereto as shown in FIG. 1.

The spindle 14, as depicted in FIG. 1, includes an annular cap 26 secured about the post 18, and a tubular bearing housing 28, the upper end of which extends into the cap. Within the housing is secured an annular block 30 which functions to support the rod 20 within the housing. At the lower end of the housing 28 is secured a pulley 29 for effecting rotation of the housing and thus the spindle 14.

Below the annular block 30 is located a stationary tubular post 32 centered in and journaled to the housing 28 by upper and

lower sleeve bearings

34 and 36. The lower end of the post is secured to an L-shaped structure 38 which is, in turn, bolted to a member 39 welded to a plate 40 forming part of an overall conveyor apparatus and system not shown. The upper end of the post 32 engages the annular block 30 through a thrust bearing 42.

The lower end of the solid rod 20 extends below the lower end of bearing housing 28, and below the L-shaped structure 38 rigidly supporting the stationary post 32. The lower end of the solid rod is provided with a rounded or spherical surface 43 designed to engage the surface ofa cam or track member (not shown) for lifting the post in the manner explained hereinafter.

The upper end of the solid rod 20 is provided with a threaded bolt member 44 threaded into a bore provided in the rod. The upper end of the threaded member is provided with a pointed projection 46 adapted to pass through a hole provided in the center of the cover 12. The bolt 44 further supports three laterally extending and upwardly pointing L-shaped arms 48 (FIG. 3) adapted to engage and support the cover 12 in a balanced manner when the center rod 20 is lifted. As seen in FIG. 3, the arm means are joined together (preferably by welding) to form a center triangle 47 through which the bolt 44 extends. The arms are attached and secured to the bolt by suitable nuts threaded thereon and located above and beneath the arms.

To assist in positively centering and holding the cover 12 on the three arms 16, and to mask a downwardly depending rim portion 49 of an inwardly directed cover flange, a cylindrical mask 50 is provided to seat on and positively engage the arms. This is accomplished by providing three corresponding slots 52 in the lower edge of the mask, only one such slot being visible in FIG. 1. These slots engage the arms in such a manner that the mask cannot move on the arms during rotation of the fixture 10. The upper part of the mask is provided with a tapered, narrow portion 54 which engages the underside of the cover flange in an area outside its rim portion 49.

To apply a glossy porcelain coating to the outside surface of the cover 12, and to apply a frit coating to the inside surface thereof, the cover is first disposed on the mask 50 as shown in F lG. 1. Power to the conveyor is then applied to convey the fixture with the cover to a spraying station and booth not shown. The station would include spray guns suitably located beside the conveyor, the gun or guns for applying the glossy coat being positioned above the level of the cover while the guns for applying the frit coating being located beneath the level of the cover.

The guns for spraying the inside surface of the cover are directed so that substantially only the interior of the cover is coated with the interior spray material. Similarly, the exterior guns are located such that essentially only the exterior surface of the cover is coated with the exterior material. By virtue of the mask 50, the outside surface of the rim 49 does not receive the exterior coat thereby providing a porcelain coated cover having no exterior porcelain deposits on the portions of the cover that are located inside of a container. in the present invention, the mask 50 serves this purpose as well as providing a means to positively secure and center the cover on the arms 16 ofthe fixture 10.

Before the spray guns are activated, the fixture is rotated by a suitable drive means, such as a fractional horsepower motor coupled to the pulley 29, to spin the cover so that the porcelain coatings are evenly applied thereto. Because of the positive retention offered by the mask 50 and the projection 46 of the bolt 44, the cover can be rotated at substantial velocities without becoming off center and flying off the fixture thereby increasing production capabilities of the conveying and coating equipment, and thus, attaining economies unattainable with prior art fixtures.

When the process of coating the cover 12 is completed, the rod 20 is lifted by a fixed sliding surface (not shown) disposed in the path of the fixture l0 and in the path of the rounded end portion 43 of the rod as the conveyor moves the fixture 10 along its path of travel. When the rod moves upwardly, the pointed ends of the arms 48 engage the underside of the cover to lift it above the mask 50. The lateral disposition of the arms 48 serves to balance the cover horizontally above the mask until a means, such as a forked-shaped holder (not shown) can be disposed beneath the cover to remove the same from the fixture.

The invention has thus far been described in connection with a cover for a pot or pan, and with means for coating the interior and exterior surfaces with porcelain coatings. The fixture 10, however, can be employed to positively center and hold a pan 55 (FIG. 4) or other types of containers on which it is desired to coat or otherwise treat the surfaces thereof. To this end, the mask 50 is removed, and the pan is disposed upside-down on the arms 16 of the fixture 10, the arms being provided with inverted U-shaped pins 56 fixed therein as shown in FIGS. 1 and 4. In FIG. 2, each arm is shown provided with three pins 56A, B and C located at three different radial distances from the center of the fixture. In this manner, the fixture can accommodate three different size pans or pots. When the pan or pot to be coated is disposed upside-down on the arms 16, the inside surface of the pan engages one set of the three pins (A, B or C) depending upon the diameter of the pan. In FIG. 4, the pan 55 is shown engaging pins B, only one of which is shown in the Figure.

The coating process for pans is similar to that described above in connection with the cover 12. The fixture l0 conveys the pan into a spray booth where the interior and exterior surfaces thereof can be simultaneously sprayed with coatings of a desired material, quality and color without the necessity of removing the pan from the fixture until the process is completed.

Ordinarily, the lifting mechanism of the invention is not needed with pots and pans since such have handle attachments with which they can be lifted from the fixture and transported to another location. However, with pans having no handles, and depending upon the depth of the pan, the height of the bolt 44 above the rod 20 can be adjusted therein to permit suitable engagement of the pan by the pointed arms 48 when the rod is lifted at the completion of the coating process. The pointed projection 46 at the top of the bolt would be removed since there is no hole in the pan for accommodating same.

The spindle 14 may be provided with a device for orienting the fixture and cover (or pan) when rotation of the spindle is stopped. in FIG. 1, this is accomplished by a spring-biased ball plunger 58, secured in the L-shaped member 38 supporting the stationary post 32, and a tapered block 59 secured to the underside of the pulley 29 and curved around the bearing 36. During rotation of the spindle, the direction of the taper of the block is such that the ball plunger is depressed and released by rotation of the tapered block. When the spindle is stopped, the wide end of the tapered block has sufficient width to engage the ball plunger in a manner that will not cause its depression thereby preventing rotation of the spindle in the opposite direction. Rotation in the regular direction (i.e., the direction of block taper) is prevented by the drive means acting upon the pulley.

From the foregoing description, it should now be apparent that a new and useful fixture has been disclosed which positively centers and secures an article for rotation of same by the fixture. The fixture further includes means for lifting the anicle from the fixture. These ends are accomplished by a vertically disposed spindle having at least three arms rigidly attached adjacent the upper end of the spindle, a center lift rod slidably disposed within the spindle, and pin or mask means provided on and secured to the arms. Additionally, the fixture provides means to coat the inside and outside surfaces of the container in one operation.

Though the invention has been described with a certain degree of particularity, changes may be made therein without departing from the scope and spirit thereof.

What is claimed is:

l. A structure for supporting a shell in a process in which the structure rotates the shell, said shell having an inwardly directed flange and a rim portion depending therefrom, said supporting structure comprising a vertically disposed spindle mounted for rotation about its vertical axis,

a plurality of arms rigidly attached to said spindle, and

radiating outwardly therefrom,

a cylindrical mask disposed on said arms, and having an upper edge for engaging the shell flange outside the area of its depending rim portion so that the depending portion is inwardly disposed of said mask,

means on said arms retaining said mask,

means mechanically associated with said spindle for verti- V callylifting the shell independently of the mask, and

means fixed to said spindle to effect rotation of same, and thus rotation of the arms as well as the cover and mask.

2. The structure of claim 3 in which the shell has a centrally located opening, and the center post has a pointed end portion for extending through said opening when the shell is disposed on the mask.

3. The structure of claim 1 in which the spindle is a tubular structure having a center bore,

the means for lifting the shell including a center post slidably mounted within said bore, and having means adjacent the upper end of said post for engaging and lifting the shell from the arms when the post is lifted a predetermined distance within the bore.

4. The structure of claim 3 in which the means for engaging and lifting the shell include arm means attached to the center post, and extending outwardly therefrom, each of said arms having a pointed end portion extending in an upward direction. 5

UNITE STATES A ENT OFFICE a I 'CERTEFICATE ECOREQTIUN Pa ent No. 3,633,540 Dated Jan. 11, 1972 Inventor) Alfred Bolt and James S. Wood- It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

- 111 the Claims: I Make Claim 2 Claim 3.

I v Make Claim 3 Claim Cl; 2, line 1 'I Change "olaim 3" to claim 2";

c1. 4, line 1 Change "claim 3" to claim 2".

Signedend sealed thisBOth day'of May 1972.

(SEAL) Attest:

EDWARD M.FLET0HER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM P0-1050 (10-69) -Qc 60376-1559 k U.S. GOVERNMENT PRINTlNG OFFICE I I969 0-366-33

Claims

1. A structure for supporting a shell in a process in which the structure rotates the shell, said shell having an inwardly directed flange and a rim portion depending therefrom, said supporting structure comprising a vertically disposed spindle mounted for rotation about its vertical axis, a plurality of arms rigidly attached to said spindle, and radiating outwardly therefrom, a cylindrical mask disposed on said arms, and having an upper edge for engaging the shell flange outside the area of its depending rim portion so that the depending portion is inwardly disposed of said mask, means on said arms retaining said mask, means mechanically associated with said spindle for vertically lifting the cover independently of the mask, and means fixed to said spindle to effect rotation of same, and thus rotation of the arms as well as the cover and mask.

3. The structure of claim 1 in which the spindle is a tubular structure having a center bore, the means for lifting the shell including a center post slidably mounted within said bore, and having means adjacent the upper end of said post for engaging and lifting the shell from the arms when the post is lifted a predetermined distance within the bore.

4. The structure of claim 3 in which the means for engaging and lifting the shell include arm means attached to the center post, and extending outwardly therefrom, each of said arms having a pointed end portion extending in an upward direction.