US3089687A

US3089687A - Walking beam mechanism

Info

Publication number: US3089687A
Application number: US70221A
Authority: US
Inventors: William H Peck
Original assignee: Selas Corp of America
Current assignee: Selas Corp of America
Priority date: 1960-11-18
Filing date: 1960-11-18
Publication date: 1963-05-14
Anticipated expiration: 1980-05-14

Description

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May 14, 1963 Filed Nov. 18, 1960 W. H. PECK WALKING BEAM MECHANISM FIG.

5' Sheets-Sheet 1 INVENTOR. WILLIAM H. PECK ATTORNEY.

w. H. PECK WALKING BEAM MECHANISM May 14, 1963 5 Sheets-Sheet 2 Filed NOV. 18, 1960 INVENTOR. WILLIAM H. PEcK ATTOR NEY.

May 14, 1963 w. H. PECK 3,089,587

WALKING BEAM MECHANISM Filed Nov. 18, 1960 3 Sheets-Sheet 3 INVENTOR. WILLIAM H. PECK ATTORNEY.

Unite tates 3,@893587 Patented May 14, 1963 ine Filed Nov. 18, 1960, Ser. No. 70,221 9 Claims. (Cl. 263-6) The present invention relates to furnaces, and more particularly to a walking beam mechanism for moving work to be heated -through the furnace. This mechanism is so designed that the work supporting and moving members are periodically rotated so that they will be kept straight, and will wear evenly, thus prolonging their life and efficiency.

In walking beam mechanisms, there is provided one or more work supporting members that are periodically raised above the level of the hearth and moved lengthwise thereof to shift the work lthrough the furnace. These members are generally of refractory construction to withstand the 4temperatures that are encountered. Such a construction is heavy, and is subject to rapid wear due to the action of the work thereon as the work is repeatedly raised and lowered. Metallic members, which would withstand the abrasion of the work, are not satisfactory because they will warp or bend under the combined effect of the heat `and the weight of the work.

It is an object of the invention to provide a walking beam mechanism for a furnace in which the work engaging portion of the mechanism is periodically rotated to .present a different surface to the work.

It is a further object of the invention to provide mechanism for moving work through a furnace in which the work supporting members are kept straight by the action of the work on them, and one in which the Work supporting members can readily be changed, if necessary.

In carrying out the invention, there is provided a walking beam mechanism, that may have conventional actuating elements, for moving work to be heated through a furnace. The work supporting and moving members of this mechanism, however, extend the length of the furnace, and they are periodically rotated for a portion of a revolution. Thus, these members present different surfaces to the work, -so that, if one portion of a member is distorted due to heat or work, it will be bent back into shape when it again lifts the Work.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its advantages and specific objects attained with its use, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and descri-bed a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a section View taken generally on line 1 1 of FIG. 2.

FIG. 2 is a section through the furnace taken on line 2 2 of FIG. 1,

FIG. 3 is an end view of the furnace from the entrance end taken on line 3 3 of FIG. 1,

FIG. 4 is a plan view of the entrance of the hearth taken on line 4 4 of FIG. 1,

FIG. 5 is a View of the work supporting member rotating means taken on line 5 5 of FIG. l,

FIG. 6 is a section taken on line I6 6 of FIGS. 4 and 5, and

FIG. 7 is a diagrammatic view of the work supporting member rotating mechanism.

Referring to the drawings, there is shown a furnace 1 having a furnace chamber 2 in which the work, which may take the form of slabs or plates, for example, may

be heated. The chamber is provided with a roof 3 and a hearth 4, and is heated by any conventional burners 5 that will give the desired temperature and atmosphere.

In Ithe operation of the furnace, work is moved from a loading platform through an entrance 6 to the left, along the `furnace through a discharge opening 7 to a discharge platform which comprises an extension of the hearth.

Work is moved through the furnace by means of a walking beam mechanism, which includes longitudinally extending work supporting members or rails 8 of alloy steel. These members rest on `supports 9 extending upwardly from a rigid frame 11 located below the hearth. In order for the work supporting members to be given their proper movements, which will be described below, the hearth is provided with a plurality of longitudinally extending grooves 12 in which the members 3 are received, and is provided with a plurality of slots 13 through which the supports 9 extend between the members 3` and frame 11.

Vertical movement is given to the frame and the supporting members to move these members from a position in grooves 12, below the level of the hearth, to a position above the hearth, by means of a plurality of bell cranks 14 that are pivoted at 15. These bell cranks are provided with rollers 16 that engage plates 17 fastened to the bottom of frame 11. It is noted that a weight 18 may be used in connection with each bell crank, in order to help counterbalance frame 11 andy parts attached thereto. The bell cranks are moved in unison, in order to raise and lower the frame, by means of a link 19' that is attached to the vertical leg of each bell crank, with the right end of the link being fastened to one `arm of a bell crank 21 that is pivoted at 22. Bell crank 21 is positively moved in a clockwise direction to raise lthe hearth by means of an engagement between a roller 24 on its horizontal arm and a positively rotated cam 23.

Horizontal movement is given to frame d1 and the parts carried thereby by means of a link 25 that is pivoted to the frame by a pin 26 extending between a pair of projections 27 on the end of Ithe frame. The right end of link 25 is provided with a slot 28 that receives a drive pin 29 extending from the face of a rotating disc 31.

In the operation of the apparatus, the frame 11 and the members 8 carried thereby are moved in a substantially rectangular path. With the parts, as shown in FIG. l, the frame is moved vertically, so that members 8 are raised above the level of the hearth to lift the work from the hearth. The frame is then moved to the left to shift the work from the entrance toward the discharge end. The frame is then moved vertically downward to the level shown in FIG. 1, and returned to the right to that position. This movement is accomplished by means of disc 31 and cam 23 that are rotated in synchronism by some means, not shown. The cam is so formed that the bell crank levers will be moved to raise the hear-th by cam 23, while pin 29 is moving through the upper quadrant of its travel from the right to the left end of slot 28. Continued rotation of disc 31 will bring the pin into engagement with the left end of slot 28 to move the frame to the left. During this time, the cam 2.3` will keep the frame in its elevated position. Continued rotation of the cam will lower the frame while pin 29 is moving from the left to the right end of slot 28. By the time this has taken place, frame 11 will have been lowered by cam 23, so that the action of pin 29 on link 25 will move the parts back to the position' shown in FIG. 1, thus completing a cycle.

A loading platform is made to the right of entrance 6 of the furnace by bars `55. iBars 55 each have one end resting on the hearth, with the top of the bar flush with spaans? the hearth surface. The outer end of each bar is supported by braces 55. The right ends of members 8 4also extend beyond the furnace entrance to move work from the bars. Also, the member rotating apparatus, to be described, is located away from the heat of the furnace.

The supporting members 8 are periodically rotated to bring new or different portions of their surfaces into work engaging position as the work is being moved through the furnace. For this purpose, the upper end of each of the supports 9 is formed as an open yoke 32, as shown best in FIG. 2, so that the members 8 merely rest on and can rotate freely in the yoke. The rotation of members 8 is accomplished by a one-way drive on their right ends, which extend beyond the entrance 6 of the furnace, and each of which is received in -a socket formed in a drive member 33. Each member 8 can be tack welded in the socket, so that it will rotate Vwith the drive member, and so that it can easily be removed for replacement when this becomes necessary. Each drive member is received in a bearing 35 on the upper end of a support 36 that is also rigidly attached to frame 11. A ratchet driving mechanism is provided, which includes a ratchet member 3'7 received on Ia square end 34 of member 33, with a pall 33 cooperating with the ratchet teeth, as best shown in FIG. 5. The pall is `carried by a ring 39 that has a downwardly extending handle or arm 4l. `It will be seen that, `as the arm and ring are oscillated, each of the drive members -33 and the work supporting member S attached thereto will be rotated an amount depending upon the angle through which arm 41 is oscillated and the number of teeth on the ratchet.

Each of the members 8 is provided with a similar ratchet drive mechanism, and all of them are moved in unison. For this purpose, the lower ends of the arms 41 are attached to a connecting rod 42 that is reciprocated by a drive member 43 attached to the end of -a piston received in a double acting -air cylinder 44.

Air is admitted periodically to opposite ends of this cylinder -by means that `are shown diagrammatically in FIG. 7. It will be seen that air is supplied to the left end of the cylinder 44 through a pipe 45 and to the -right end of the cylinder through a pipe 46, both of which are supplied `from a suitable source of air under pressure from pipe 47. Pipe 45 has a three-way solenoid valve in it that, when energized, will connect pipe 45 with the atmosphere. Similarly, pipe 46 has a three-way solenoid valve 49 in it which, when energized, connects pipes 46 and 47, and which, when de-energized, will connect pipe 46 with the atmosphere. The

valves

43 and 49 are alternately energized by means of a timer 51 of the type I which periodically closes first one `switch and then the other when the timer is operating. This timer is controlled so that it will be operating to rotate -members S when these members are below the level of the hearth and no load is on them. To the end there lis provided a switch 52 having an actuating arm 53 that is engaged by a plate 54 fastened to the bottom of the side of frame '11, as shown in FIG. l. Whenever the frame is in its lowermost position, so that the ymembers 8 are received in grooves 12 of the hearth, switch 52 will be closed to operate the timer. During this time, air will be admitted alternately to the opposite ends of cylinder y4lito reciprocate connecting link 42. As this link reciprocates, it will Work arms 41 to rotate members 8 by means of the ratchets. It is noted that the level at which members S will start being rotated will depend upon the vertical location of switch 52.

In the overall operation of the apparatus, work is placed on the projecting ends of bars 55 that extend to the r-ight in `front of the furnace entrance. The walking beam mechanism is started, so that the members 8 will lift the -work from the bars and carry them step by step through the furnace lfor the heating. During such times as the members 8 are above the surface of the hearth and supporting the work, the members will not be rotated. As soon as the walking beanr mechanism has been operated to a point that the members are moved below the surface of the hearth, in channels 12, switch 52 will be closed to start timer 51. Thereafter, members S will be rotated a number of steps, depending upon the speed of the timer, so that a new or different surface of each member 8 is presented to the work each time the walking beam mechanism is raised.

Members 8 are and have the usual characteristics of expanding under heat. Since only one end of each of the members is held, they can expand freely in yokes 32 toward the exit end of the furnace. Thus, there will be no bending due directly to furnace heat. lf, due to the `load they carry, these members 8 are bent slightly, they are immediately bent back to proper shape by the work as they are rotated, since the work load is placed on different portions of the surface of these members during each operation. When, after a period of time, the members have become worn to the extent that they must be replaced, it is easy to break the tack weld between a drive member 33 and the members. Then a member can be moved to the left out of the furnace, and a new one inserted.

As shown herein, the lightweight work supporting members extend lengthwise of the furnace. In many cases, this is desirable because of the shape or type of work that is being heated. It is obvious, however, that the members could extend transversely of the furnace through suitable openings in the sides thereof, and still operate in exactly the same fashion with the same advantages. The rotation of members 8 also has the advantage of insuring that these members are heated evenly throughout. This aids in reducing distortion and increasing their life.

Jhile in accordance with the provisions of the statutes, I have illustrated and described the best form of embodiment of -my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the lform of the apparatus disclosed without departing from the spirit and scope of the invention set forth in the appended claims, and that in some cases certain features of my invention may be used to advantage Without a corresponding use of other features.

What is claimed is:

l. ln combination, a furnace having a hearth therein along which work is moved to be heated, said hearth being provided with a plurality of elongated and parallel spaces, an elongated work supporting member in each space, means simultaneously to move said members from a position in said spaces below said hearth to a position above said hearth, means to reciprocate said members in the direction of work movement along said hearth, means to coordinate said moving means and said reciprocating means whereby when said members are above said hearth they will be moved in the direction of work movement along said hearth, means to rotate said members around their axes, and means operated when said members are in their low position to actuate said rotating means.

2. The combination of claim 1 in which said means to rotate includes a drive device, and means to operate said drive device intermittently.

3. In a walking beam mechanism to be used with a furnace, a frame, a plurality of parallel rows of posts extending upwardly from said frame, a plurality of elongated work supporting members, means to mount one of said members for rotation on each row of posts, a oneway rotating device on one end of each member, an oscillatable arm connected to actuate each device, a reciprocating bar connected to said arms to oscillate them in unison as said bar is reciprocated, reciprocating means operatively connected to said bar, means to raise and lower said frame, and means operated by said frame when it is lowered to a given level to actuate said reciprocating means.

4. A walking beam mechanism for use in a furnace comprising a frame, aligned posts extending upwardly from said frame, an elongated supporting member, means to mount said supporting member for rotation on the upper ends of said posts, a one-way rotating device on an end of said member including an arm extending radially from said device, means mounted on said frame to oscillate said arm and thereby operate said device to rotate said member, means to raise and lower said frame, and means actuated by lowering of said frame to aotuate said oscillating means.

5. The combination of claim 4 in which there are a plurality of parallel supporting members on said frame each of which has on its end a one-way rotating device having an arm extending therefrom, means to connect said arms for movement together, and means to move said connecting means by said means to osciiiate.

6. In combination with a furnace having a hearth, mechanism to move Work to be heated along said hearth including a plurality of elongated work supporting members, means to move said supporting members from above said hearth to below lsaid hearth, means to rotate said supporting members around their axes, and means operative in response to lowering of said members to actuate said means to rotate.

7. A walking beam mechanism including a frame, means to move said frame through a substantially rectangular path including an upper and a lower position, aligned supports extending upwardly from said frame, elongated work moving members rotatably mounted on said supports, means to rotate said members intermittently, and means operated by said frame to prevent operation of said rotating means when said frame is in its upper position.

8. In a furnace structure, a heanth, a walking beam mechanism to move work along said hearth, means to move said mechanism through substantially a rectangular path having a high portion and a low portion, a work supporting member, means to mount said member for rotation on said mechanism, said member being above said hearth at the high portion of its path and below said hearth at the low portion of its path, means to rotate said member, means to operate said rotating means, and means to control the operation of said voperating means as said mechanism yis moving through a portion only of its path.

9. A walking beam mechanism to move work in a given direction, said mechanism being provided with a frame, means -to move said frame through a substantially rectangular path having Ihorizontal movement in a direction of movement of the work and having a high position and a low position, supports extending upwardly from said frame, work supporting members mounted for rotation on the upper ends of said supports, means intermittently to rotate said members, and means to operate said means to rotate only when said frame is not in the high position of its path.

References Cited in the iile of this patent UNITED STATES PATENTS 805,041 Turner Nov. 2l, 1905 2,039,203 yOgilvy-Webb Apr. 28, 1936 2,883,171 Munford Apr. 2l, 1959

Claims

8. IN A FURNACE STRUCTURE, A HEARTH, A WALKING BEAM MECHANISM TO MOVE WORK ALONG SAID HEARTH, MEANS TO MOVE SAID MECHANISM THROUGH SUBSTANTIALLY A RECTANGULAR PATH HAVING A HIGH PORTION AND A LOW PORTION, A WORK SUPPORTING MEMBER, MEANS TO MOUNT SAID MEMBER OF ROTATION ON SAID MECHANISM, SAID MEMBER BEING ABOVE SAID HEARTH AT THE HIGH PORTION OF ITS PATH AND BELOW SAID HEARTH AT THE LOW PORTION OF ITS PATH, MEANS TO ROTATE SAID MEMBER, MEANS TO OPERATE SAID ROTATING MEANS, AND MEANS TO CONTROL THE OPERATION OF SAID OPERATING MEANS AS SAID MECHANISM IS MOVING THROUGH A PORTION ONLY OF ITS PATH.