US1802109A - Car-stopping apparatus - Google Patents

Description

INVENTOR a (6 3W) 5 Sheets-Sheet '1 A. E EVANS ET AL CAR STOPPING APPARATUS Filed Feb. ll, 1930 April 21, 1931.

J $2 w Y L A ril 21, 1931. A. E. EVA-NS ET AL CAR STOPPING APPARATUS Filed Feb. 11. 1930 5 Sheets-Sheet 2 April 21, 1931.

CAR STOPPING APPARATUS 5 Sheets-Sheet 3 Filed Feb. 11. 1930 INVENTOR6 April 21, 1931. EVANS ETAL 1,802,109

CAR STOPPING APPARATUS Filed Feb. 11, 1930 5 Sheets-Sheet 4 law wind INVENTORE) April 21, 1931. A. E. EVANS ET AL CAR STOPPING APPARATUS Filed Feb. 11. 1930 5 Sheets-Sheet 5 2% it I INVENTOR5 Patented Apr. 21, 1931 UNITED STATES PATENT OFFICE ALBERT E. EVANS, OF PITTSBURGH, AND GUSTAVUS I. NAMECHE, OF FORD CITY, PE-1\Tl l'..

SYLVANIA, ASSIGNORS TO PITTSBURGH PLATE GLASS COLIPANY, A CORPORATION OF PENNSYLVANIA oAa-s'rorrine APPARATUS Application filed February 11, 1930; Serial No. 427,547.

The invention relates to car stopping apparatus for use on the return track of a plate glass surfacing system. In a system of this kind, the glass to be surfaced is secured to the tops oi cars or tables, which form a train and are moved on the work track slowly beneath a series of grinding and polishing runners. The cars are then returned to starting position on a return track which parallels the wor: track, this being accomplished by an endless cable or drag chain, which is provided with dogs.

which engage the racks on the bottoms of the cars. During the period of return, each' car must be stopped whilethe workmen remove the sheet of polished glass held in po sition on the bed of the car by means of plaster. This requires several minutes during which time it is necessary for the workmen to stand between the car tracks as well as at the sides. The purpose of the present invention is to provide improved means to stop the cars for the glass removing or stripping operation, which includes means "for releasing the dogs bywhich the cars are secured to the drag chain and means for braking the cars. A further object is to provide means of the character specified which is automatic or semi-automaticin operation and so arranged as to afford protection for the workmen, and eliminate the possibility of any of them being caught between the car which is being stripped of its glass, and the next car of the series which is being moved along by the drag chain. Certain embodiments of the invention are illustrated in the accompanying drawings, wherein:

Figure 1 is a plan view showing the gen eral arrangement of the apparatus. Fig. 2

and polishing machines, this being a means well known in the art for accomplishing'this purpose. Extending longitudinally of the work When the cars are track 1 is an endless drag chain for giving 7, thecars their'movement along the track,

such drag chain passing around a pair of sprockets at the ends of the track, a suitable means being provided for driving one of the sprockets. The drag chain constitutesthe means for moving the cars along the track and to this end is provided with a series of spaced dogs 6,6, 6, etc. adaptedto engage the rack oars 4 and move the cars along the track. These dogs are preferably constructed as indicated in Fig. 4; with an end? adapted to fit between the teeth oi? the rack. The dogs are pivoted upon the pintlesS oi the drag chain and eachhave an end 9 which is heavier than the end 7, so that normally the end '7 is held in position to engage theteeth of the rack 4;. 'VVhen the dog is in this position therefore, the car l is moved along its track at a relatively low rate of speed.

As heretofore pointed out, it is necessary to stop the cars successively for limited periods in order to remove the glass sheet carried thereby, and in order to thus stop the car, the dog 6 must be moved to the release position shown in Fig. l. This is accomplished by means of a cam 10 having its ends turned down, as indicated in Figs. 2 and l, normally held in the position indicated in these figures. The cam is prefer ably formed of two angles placed backto back, as indicated in Figs. 5 and 6, and supported by a series of arms-11, 12, 13, 14 and 15 pivoted at their upper ends to the cam and carried at their lower ends on pivots 16, 16, 16. 16 and to the shaft 17. and the shaft 17 are carried in suitable frame members, such as 18, 18 and 19, 19 shown in Figs. 6 and 7, such members being suitably anchored to the foundation 20 by means of the bolts 21, 22, etc. The shaft 17 which carries the arm 13 is supported in suitable bearings 23, 23 (Fig. 7) and is extended laterally and provided with a squared end 2-1. for the application of a wrench or other suitable tool whereby the lever 13 may be rocked so as to raise and lower the cam 10. Power means are also provided for rocking the lever 17 to raise and lower the cam in the form of the air cylinder provided with a suitable plunger and piston rod 26, the end of which is pivoted at 27 to the lower end of the lever 13. When the cam 10 is in the position of Fig. 2, and the table 2 is carried over the cam by the drag chain 5, the cam engages the end of the dog 6 and swings it to unlocked position, as indicated in Figs. 2 and 4, thus releasing the table from the motive power tending to carry it forward. hen it is desired to again couple up the table to the drag chain, the cam is swung forward by admitting air to the air cylinder 25, which causes the upper end of the lever .13 to swing forward. The cam is in this manner lowered and any dog 6 which happens to be beneath. the table 2 swings to operative position, so that its end 7 engages the rack +1, thus coupling the table to the drag chain.

In order to overcome the inertia of the table and cause it to stop within a short distance after the dog 6 has been released, suitable braking means are provided along the line of movement of the :ars adjacent the cam .10 which releases the dog. This means comprises a pair of opposing brake shoes 28, 28 located on opposite sides of the cam and spring pressed inward so that they frequently engage surfaces on the lower side of the car body. The :-:urfa 'e:-; which the brake shoes engage are preferably the sides of the rack bars 4, the shoes being shown in engagement with such rack bars in Fig. 6. The shoes are preferably Tshape in cross section and are provided with wear plates 29, 29. The shoes are mounted for moven'ient toward and from each other upon crank arms 30, 30 and 30, 30 carried upon the vertical shafts 31, 31, and 32, 02s journalled in the frame members 18. The lower ends of the shafts 31, 31 and 32, 82 are provided with crank arms 33, 33 and 38, 33 connected to the rods 34, 34; and 3t, 3 1- The rods are mounted slidably at their outer ends in sleeves Fig. 6) and adjusting nuts 36 are threaded to these sleeves inside the brackets 37 through which the sleeves extend. A washer 38 is carried adjacent the The pivots 16 inner end of each of the rods 34, and be tween such washer and the sleeve 35 a spring 39 is positioned. By adjusting the sleeves 35, the springs 39 are placed under any desired degree of compression and this presses the shoes 28 inward so that when they engage the rack bars 4-, the cars will be stopped as soon as may be desired. "he degree of compression which is required in the springs 39 is easily determined by trial. The sleeves are adjusted by means of the rods 40 which have their inner ends squared and fitting into the sleeves 35 and also have their outer ends squared for the reception of a wrench or other suitable adjusting tool.

After the table has been stripped of the glass plate carried thereby and it is desired that the table should continue its forward movement, the brake shoes must, of course, be released and this is accon'iplished by the actuation of the means which lowers the cam 10 in order to permit one of the dogs 6 to swing by gravity so that it will engage the rack bar 4. as heretofore described. The movement of the brake shoes to disengage them from the sides of the rack bar is accomplished by means of the pairs of toggle links i1, i1 and 41, 41 (Fig. 3) which are connected at their outer ends to the pairs of' lever arms 42, -12 secured to the lower ends of the vertical shafts 31, 31 and 32, 32. The inner ends of the toggle links 11, 1:1 and 4:1, 41 are pivotally connected to a release member comprising the two end brackets d3, 43 connected together by the link M. The right hand. bracket (Figs. 3 and 4) is connected by means of the link it with the lever 13, which lever serves to move the cam member 10 up and down, as heretofore explained. It follows that when the lever 13 is rocked around the shaft 17 to lower the cam, the links 11, 1-1 and -11, 41 are moved inward, thus rotating the shafts 33', 31 and 32, 32, so that the arms 33, 33 and 33, 33 are swung outward, thus releasing the brake shoes. At the same time the downward movement of the cam member 10 permits the dog (3 lying beneath the rack 4: to engage such rack so that the forward movement of the drag chain carries the table ahead.

As shown in Figs. 1 and 2, two sets of cams and brake shoes are provided so that the two tables 2 and 3 are stopped in the position shown. The cam and braking devices for stopping the car 3 are precisely the same as those for stopping the car 2 heretofore described and the purpose of providing the second set of aims and brake shoes for stopping the car 3 is to protect the workmen who are engaged in removing the glass from the table 2. The table 3 will always be stopped in the position shown, preferably about six feet from the table 2, although this may be modified to meet varying conditions. After the glass has been removed from the table 2, as heretofore described, the cam and braking devices are released by admitting air to the cylinder 25, and after this has been done, one of the operators similarly releases the table 3 by operating the valve which admits air to the cylinder 25a. lhe two tables are then moved forward by the drag chain and when the table 3 reaches the position formerly occupied by the table 2, it is automatically stopped as heretofore described, while a third table which is approaching from the right takes the place of the table 3 being automatically stopped in the position formerly occupied by the table 3. If desired, the cam and brake-releasing devices may be operated by hand by applying a tool to the shaft 17 (Fig. 7), as heretofore described, although the amount of force required to move the parts is very considerable so that the cylinder 25 is ordinarily used.

Fig. 8 illustrates a modification showing how the operation of the apparatus may be made entirely automatic, thus dispensing with the requirement by the workmen to operate the valves of the cylinder 25 or the shaft 17. In this construction, the means for supporting and operating the cams l0 and the brake shoes is substantially the same as that described in connection with Figs. 1 to 7, but instead of having the lever '13 operated from the air cylinder, this lever 13 is operated by a lever 45 connected to the lever 13 by a link as. The lever 45 is provided at its upper end with a roller which lies in the path of movement of the table 47 which is following the table 48. ,A similar arrangement is provided immediate the table 48 and the table 47 which precedes it. The forward movement of the table L7 serves to release the table 48, and as soon as this table is released, it moves forward and causes the release of the table 4 7, the latter table being the one upon which the workmen operate to remove the glass. EBy this arrangement the tables are kept spaced apart a uniform distance and the workmen are relieved of the labor incident to the starting and stopping of the tables.

\Vhat we claim is:

1. In combination with a return track, a seriesof cars thereon, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals'normally engaging the cars for moving them along the track, and a movable cam located along the path of movement of the dogs and adapted, when in one position,'to engage the dogs and move them to release position, and when in another position, to "be free of operative engagement with the dogs.

2. In combination with a return track, a series of cars thereon, and a driven endless drag-member beneath the cars, releasable dogs on the drag member at spaced intervals normally engaging the cars for moving them along the track, and a pair of movable cams located at spaced intervals along the path of movement of the dogs and each adapted, when in one position, to engage the dogs and move them to release position,and when in another position, to be free of operative engagement with the dogs.

3. In combination with a return track, a'

series of cars thereon, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals normally engaging the cars for moving them along the track, a movable cam located along the path of movement of the. dogs, and adapted, when in one position, to engage the dogs and move them to release position, and when in another position, to be free of operative engagement with the dogs,=,braking means for the cars which become effective to check the movement of the cars when the dogs are released, and means formoving the cam to position to release the dogs and also moving the braking means to release position.

4. In combination with a return track, a series of cars thereon, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals normally engaging the cars for moving them along the track, a movable cam located along the path of movement of the dogs, and adapted, when in one position, to engage the dogs and move them to release position, and when in another position, to be free of operative engagement with the dogs, braking means for the cars located along the path of movement of the c; adjacent said cam and yieldingly held in position to engage a car and check its forward movement when the dog-which moves the car is released by the cam, and a common means for moving the cam to position to release said dog and also moving the braking means to release position.

5. In combination with a return track, a series of cars thereon, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals normally engaging the cars for moving.

them along the track, a pair of movable cams located at spaced intervals along the path of movement of the dogs, and each adapted,when in one position, to engage the dogs and move'them to release position, and when inanot-her position, to be free of operative engagement with the dogs, a braking means located along the'path of movement of the cars adjacent each of said cams and each yieldingly held in position to engage a car and check its forward movement when the dog which moves the car is released by its cam and a common means for moving each cam and the braking means adjacent thereto.

(5. In combination with a return track, a series of cars thereon, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals normally engaging the cars for moving them along the track, a movable cam located along the path of movement of the dogs, and adapted, when in one position, to engage the dogs and move them to release position, and when in another position, to be free of operative engagement with the dogs, a brake shoe extending along the path of movement of the cars adjacent the cam, means for normally pressing the shoe yieldingly toward a part of the car so that it will frictionally engage such. part as the car moves past the shoe, and operating means connected to the cam and to the shoe so that when moved in one direction it will move the cam from its dog engaging position and will also move the brake shoe to release position.

7. In combination with a return track, a series of cars thereon, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals normally engaging the cars for moving them along the track, a movable cam located along the path of movement of the dogs, and adapted, when in one position, to engage the dogs and move them to release position, and when in another position, to be free of operative engagement with the dogs, a pair of opposing brake shoes extending along the path of movement of the cars adjacent the cam, means for normally pressing the shoes yieldingly toward each other and against the sides of a part of the car lying therebetween, so that they will frictionally engage such part as the car moves past the shoes, and operating means connected to the cam and to the shoes so that when moved in one direction it will move the cam from its dog engaging position and will also move the brake shoes apart to release position.

8. In combination with a return track, a series of cars thereon, each having a downwardly facing rack extending longitudinally of the car body on its lower side, and a driven endless drag member beneath the cars, releasable dogs on the drag member at spaced intervals having engaging parts which normally engage the racks on the cars when such racks lie over the dogs, and a vertically movable cam located beneath the path of movement of the drag member, and adapted, when in one position, to engage the dogs and move them to position of disengagement with respect to the racks, and when in another position, to be free of engagement with the dogs so that such dogs will engage the racks.

In testimony whereof, we have hereunto subscribed our names.

ALBERT E, EVANS. GUSTAVUS J. NAMECHE.

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