US3078857A

US3078857A - Etching machine

Info

Publication number: US3078857A
Authority: US
Publication date: 1963-02-26
Anticipated expiration: 1980-02-26

Description

Feb. 26, 1963 w. GUENST ETCHING MACHINE Filed June 1, 1960 2 Sheets-Sheet 1 l4 FIE.

mvcuron: WILLIAM .GUENST BY MW ATTYS- Feb; 2 6, 1963 w. GUENST zwcnmc mcazma Filed June 1. 1960 2 Sheets-Sheet 2 'F'IEL 7.

INVENTOR; WlLLIAM GUENST- A TTYS United States Patent 3,078,857 ETCHING MACHINE William Guenst, Elkins Park, Pa., assignor to Master Etching Machine Co., Wyncote, Pa., a corporation of Pennsylvania Filed June 1, 1960, Ser. No. 33,323 3 Claims. (Cl. 134-46) on a carrier which is adapted to carry the plates or cylinders along a horizontal path in the machine between a washing and treating station and an etching chamber.

Another object of the present invention is to provide novel apparatus of this type wherein the etching fluid is prevented from dropping down onto the plates or cylinders from the top of the housing when the plates or cylinders initially enter the etching chamber.

Another object of the present invention is to provide a combination machine having both an etching chamber wherein the plates or cylinders may be etched and a washing or treating station wherein the plates or cylinders may be washed or otherwise treated before or after the etching operation.

Still a further object of the present invention is to provide a novel etching machine which is extremely versatile and is adapted to etch curved or arcuate plates or cylinders of different sizes and radii.

A still further object of the present invention is to provide a novel etching machine having the features and characteristics set forth above which is of relatively constructoin thereof are hereinafter more fully set forth and described with reference to the accompanying drawings, in which:

- FIG. 1 is a side elevational view partially in section of an etching machine made in accordance with the present invention;

FIG. 2 is an enlarged transverse sectional view through the etching chamber taken on line 2--2, FIG. 1;'

FIG. 3 is an enlarged fragmentary sectional view taken on line 33, FIG. 1;

FIG. 4 is an enlarged fragmentary longitudinal sectionalview through the etching chamber of the etching "machine with the carrier for the plates to be etched in position in the etching chamber;

FIG. 5 is a fragmentary transverse sectional view taken 7 -on line 5--5. FIG. 4 illustrating the forward end of the etching chamber with the main cover in place;

FIG. 6 is a fragmentary transverse sectional view taken on line 66, FIG. 4 illustrating the means for supporting a rigid arcuate plate on the carrier;

' FIG. 7 is a fragmentary sectional view illustrating the means for supporting a flexible plate on the carrier; and FIG. 8 is a fragmentary sectional view taken on line 8-8, FIG. 4.

There is illustrated in the drawings an etching machine junction with the conventional powderless etching proc- Patented Feb. 26, 1963 ess initially developed by Dow Chemical Company and described, for example, in United States Patents Nos.

2,640,765 and 2,828,194. It will be understood, however, that any suitable etching process may be carried out on this machine, making adjustments in the machine for the type of etching fluid to be used.

With reference to the drawings, the etching machine of the present invention comprises an enclosed housing 10 having a top wall 11,

side walls

12, 12, front and

rear walls

13 and 14, respectively, and a bottom wall 15 which defines a closed etching chamber 16 wherein the etching process takes place. The etching fluid is adapted to be received in the bottom of the etching chamber 16, as illustrated in FIG. 2 and cooling coils 17 may be provided if necessary to maintain the etching fluid at the desired temperature. Additionally, circulating pumps and agitators (not shown) may be provided to continuously circulate the etching fluid and maintain the etching fluid in the desired state of agitation.

The plates to be etched are positioned within the etching chamber, as more fully described hereinafter, above the surface of the etching fluid and means are provided to cause the etching fluid to be sprayed or otherwise forced against the surface of the plates to be etched while the plates are supported in the etching chamber. In the illustrated embodiment of the present'invention'a pair of cylindrical paddles or

impellers

18, 18 are positioned within the etching chamber immediately above the electric motor 21 and a drive belt 22 as illustrated in FIG. 1 of the drawings.

g In accordance with the present invention a trough 23 is mounted outwardly adjacent the front wall of the housing 10. The trough 23. may be of generally semicylindrical form open at its' top and terminating at the front wall of the housing adjacent an access opening 24 in the front wall of the housing. .The access opening 24 is I positioned relative to the sink so' that the lower end of the. access opening is slightly higher than the lower wall of the sink preventing fluid invthe sink from entering the housing through the opening 24. Withtliis construction, the various plates to be'etched may first be. supported in a desired relation over the trough or sink 23 for an initial treating before they are moved into the etching chamber, and afterthe plates are removed from the etching chamber they are brought to a positionfover the sink or trough 23 where they are washed off. or otherwise treated before being removed from the etching machine.

An important feature of the present invention resides in the particular configuration of the top wall of the housing 10 above the etching chamber. The top wall 11 of the vhousing is so designed that it slopes downwardly at least to a position outwardly beyond the periphery of the plate to be etched when the plate is positioned within the etching chamber so that there is no danger of the etching liquid dripping off of the top of the housing onto a .plate while the plate is initially being inserted into the etching chamber. This is a particularly serious problem when the etching fluid comprises a mixture of acid and oil, for example, as in the above mentioned Patent No. 2,640,765 since any oil dropping off of the upper wall of the housing onto a plate while the plate is initially being inserted into the housing would prevent etching of the plate at the portion contacted by the oil. With the configuration of the top wall 11 as illustrated in the drawings any droplets of oil or oil and acid will run downwardly along the top wall to a point beyond the position assumed by a plate to be etched in the etching chamber before they will drop off of the top wall thereby protecting the plate.

According to the present invention a carrier 25 is provided for the plates to be etched adapted to support the plates within the etching chamber and also support the plates in the desired position over the sink or trough 23. In the present embodiment of this invention the carrier 25 as illustrated in FIGS. 1, 2, and 4 of the drawings, comprises three

separate mounting rings

26, 27, and 28 each supported from

hubs

26a, 27a, and 28a, respectively, with spiders or similar supporting members 26b, 27b, and 28b interconnecting the respective hubs and rings. A series of tie-rods 29 extend between the first and third hubs 26a and 28a and are fixedly secured to these hubs with the central hub 27a being slidably mounted on the tie-rod 29. Locking means (not shown) is provided on the central hub to lock the central hub in a desired position along the length of the tie-rods. Each of the

rings

26, 27, and 28 comprises two circular pieces of angle iron or the like maintained in spaced apart relation providing in each ring a slot 26c, 27c, and 28c, extending entirely about the periphery of the rings. Clips 31 are mounted in the slots 26c, 27c, and 28c for example by means of bolts and wing nuts as illustrated in FIGS. 2 and 7 of the drawings to permit a plate P1 to be secured to the carrier. The clips engage over the plate and hold the plate in position against the carrier ring. These rings are used when it is desired to mount a flexible thin plate on the carrier and the plate is held in an arcuate position about the carrier rmgs.

In order to permit the mounting of a relatively stiff arcuate plate on the carrier two pairs of spaced-apart

mounting tracks

33, 33 are provided with each pair of mounting tracks consisting of spaced-apart lengths of angle iron or the like adjustably mounted on the carrier providing a slot opening 34 for the full length of the carrier, for example, as illustrated in FIG. 6. Mounting clips 35 similar to the mounting clips 31 are provided and held in the slot by a bolt and wing nut as illustrated in FIG. 6 with the mounting clips adapted to engage over therelatively stitf plate P2 to be etched to maintain the plate P2 in position on the tracks. The tracks 33 are secured to the spiders 26b and 28b of the outer rings, for example, by means of bolts as indicated in FIG. 4, and extend through openings in spider 27b of the central ring. The tracks 33 may be adjusted radially of the

rings

26, 27, and 28 by securing them in any one of a series of openings 36 in the spiders 26b and 28b, as illustrated in FIG. 2.

To properly etch the plates P1 and P2 and insure that a uniform depth of etch will be obtained over the entire area of the plate, the plates should be moved constantly while subject to the action of the etching fluid. To accomplish this, in the illustrated embodiment of the present invention, the carrier 25 is mounted on a rotatable shaft 37. The shaft 37 in addition to causing rotation 'of the carrier also serves to slidably mount the carrier so that the carrier may be easily moved from a position over the trough 23 to a position within the etching chamber 16. The shaft '37 is mounted at one end in a hearing at the rear wall of the housing and the opposite end on a pair of rolls 38, 38 carried forwardly adjacent the forward end of the trough 23. A drive motor 41 is drivably connected to the forward end of the shaft 37 for example by means of a chain and sprocket as indicated at 42 in FIG. 1 to cause rotation of the shaft 37. Preferably the motor 41 is reversible and has a gear reduction unit on it so that the shaft 37 is caused to rotate at a relatively slow rate of speed. After the carrier is inserted into the etching chamber the motor is caused to drive the carrier in one direction for a predetermined period of time and then in the opposite direction for the same length of time to insure that all portions of the plates to be etched are subjected to equal action by the etching fluid. A driving connection is obtained between the carrier and the shaft, for example, by means of a pin 4-3 fixed to the inner end of the carrier and adapted to be received in an opening 4-4 in a drive plate 45 secured to the shaft 37. After the carrier is inserted into the etching chamber a cover 47 which is slidably mounted on the shaft 37 is positioned over the access opening 24 to the etching chamber and locked in place for example by means of

latches

48, 48. The cover 47 may be counter-balanced, for example, by means of a counter-weight 49 so that the cover will always engage the opening in the desired position. As a safety feature and to prevent injury to the operator of the machine, a safety switch 51 may be secured to the forward walls of the housing adapted to be engaged by a switch actuator 52 secured to the cover. The safety switch 51 may be in the control circuit to the motor 21 for the

agitators

18, 18 to prevent rotation of the agitators until such time as the cover 47 is in a closed position with the switch actuator 52 in engagement with the switch 51.

From the foregoing, it will be observed that the present invention provides a novel etching machine for etching curved or arcuate plates and cylinders wherein the plates and cylinders may be secured to a carrier which is adapted to carry the plates and cylinders along a horizontal path in the machine between a washing or treating station and an etching chamber. Additionally, it will be observed that the present invention provides a novel etching machine wherein the plates to be etched may be mounted at convenient height so that the operator may treat or wash the plates before the etching operation and after the etching operation and wherein the plates are prevented from being contacted by the etching fluid during insertion of the plates into the etching chamber.

While a particular embodiment of the present invention has been illustrated and described herein it is not intended to limit the invention to such a disclosure and changes and modification may be incorporated and embodied therein within the scope of the following claims.

I claim:

1. An etching machine adapted to etch arcuate plates, comprising in combination, an elongated enclosed housing having a bottom chamber adapted to hold a body of etching liquid and front, rear, side and top walls, means in said chamber for throwing etching liquid upward against an article to be etched, said housing having in the front wall an opening of a size to permit passage therethrough of an article carrier, a closure movable across said opening, a trough located in front of said housing and extending forward from said front wall, said trough being located at an elevation below the bottom of said opening to permit the article carrier to be moved out thereover, a shaft extending from a support on the rear wall of said housing through said opening and to a support on the front end of said trough, an article carrier slidably supported on said shaft, rotatable article-supporting fixtures mounted on said carrier, said carrier being of a size to move in and out of said opening and over said trough while the carrier is sliding on said shaft and said shaft is mounted on its end supports, and means for rotating said article-supporting fixtures when the work carrier is positioned within said housing, said shaft being rotatably mounted on said end-supports and at its rear end carrying a rotatable member which engages elements on said article-supporting fixtures when the article carrier is located in its rear position in said housing.

2. An etching machine as set forth in claim 1, in which said article-supporting fixtures include parts having circumferential and axial slots therein, and article clamps slidably mounted in said slots.

3. An etching machine as set forth in claim 1 in which said top wall is inclined throughout its length downward from a line above the middle of said article carrier to carrier.

References Cieal in the file of this patent UNITED STATES PATENTS Robertson Dec. 2, 1930 6 Robertson Jan. 12, 1937 I-Iampel Oct. 1, 1940 Arey Dec. 24, 1940 Diehm Sept. 19, 1950 Powers Aug. 28, 1951 Guenst Feb. 1, 1955