Патент USA US2113530код для вставки
April 5, 1938. H. PAXTON> 2,113,530 >AUTOMATIC CONTROL FOR NAILING MACHINES Filed Dec. 28, 1956 FIG. 1. w 75 /53 /5/ /50 ,___ ____..._.________, ATTORNEY. Patented Apr. 5, 1938 2,113,530-v UNITED ?sTATlazs PATENT OFFICEy 2,113,530 AUTOMATIC CONTROL FOR NAILING MACHINES Hale Paxton, Santa Ana, Calif., assignor to Food Machinery Corporation, San Jose, Calif., a cor poration of Delaware Application December 28, 1936, Serial No. 117,724 2 Claims. This invention relates to safety devices and has particular utility in nailing machines.` In nailing machines for making boxes auto matically the component parts of a woodenA box 5 are fed from suitable magazines by various feed ing mechanisms into the proper relation to» be nailed together to form a box and are there suit ably assembled by a nailing mechanism nailing the sides and the bottom of the box to the ends 10 thereof. In such an automatic machine all of the mechanisms contributing to the assembling of the box are operated coordinately from one source of power. In the past it has been cus tomary in operating these automatic machines to 15 control their stopping and starting with a clutch. Owing to box parts occasionally being warped and jamming one or more of the feeding mech anisms, it has been necessary for the operator of the machine to run it With one hand on the 20 clutch lever so that he could stop the machine immediately upon observing the malfunctioning of any mechanism therein. As these automatic machines produce boxes at a rate of over four hundred and ñfty an hour 25 the strain on the operator of having to watch each operation of the machine to see that it was performed correctly was a considerable handi cap in continuous operation of these machines. Furthermore, it was almost impossible for the op 30 erator to notice that things were going wrong until the diiîiculty had proceeded to such a point that a box was improperly nailed together in the machine, thus making it necessary to remove this box from the machine and rebuild it by hand. 35 In other cases the delay necessarily incident to observing the malfunctioning of certain mech anisms in the machine would result in box parts becoming jammed in the machne so tightly that the operation of the machine would have to be 40 interrupted for a long period while removing the damaged box material and resetting the machine for automatic operation. It is an object of this invention to prevent mal formation of boxes or the serious jamming of box 4.5 material in an automatic box making machine. One of the principal causes of jamming in automatic box making machines is the locking to gether of adjacent box ends by virtue of the fact in such a knot hole and keys the two pieces of shook together. Thus when the machine under takes to feed one of these pieces of shook from the magazine it is locked to a piece next thereto which is disposed back in the magazine and thus prevents the foremost piece from responding to the feeding mechanism. 5 , v One way this situation was formerly taken care of was to form a portion of the feeding mech anism feeding these box ends of such light ma- 10_ terial that it would break in case of jamming from the cause just described. The first evidence that the operator would have if he was alert would be the failure of one of the box ends to be fed into the machine at the commencement of a 15 box assembling cycle. If the operator failed to notice this omission immediately the manufac ture of an incomplete box was started before the clutch could be thrown out and the machcine stopped. Before the machine could again be started themissing box end would have to be N 0 supplied to the assembling mechanism and the broken feed device would have to be replaced. It is another object of this invention to not only eliminate the necessity of the operator hav ing to» constantly observe the operation of the 25 mechanism feeding box ends in an automatic box making machine but also to eliminate the break ing of the mechanism feeding these ends and the starting of incomplete boxes by failure of such mechanism to feed an end when required. The manner of accomplishing the foregoing objects, as Well as further objects and advan tages, will be made manifest in the following de scription taken in connection with the accom panying drawing, in which: Fig. 1 is a fragmentary side elevational view of the box end feed mechanism on one side of the automatic box making machine shown in U. S. Letters Patent No. 1,844,333 issued to Elmer C. Northrup on February 9, 1932, said view show ing said box end feed mechanism with the pres ent invention embodied therewith. . Fig. 2 is a plan view of the feed mechanism shown in Fig. 1. 45 Fig. 3 is a cross sectional view taken on the line 3_3 of Fig. 2. Fig. 4 is an enlarged fragmentary cross sec that these adjacent pieces have been sawed from Y tional view taken on the line 4-4 of Fig. 3. 50 a log at the mill without changing the relative As the particular mechanism shown in the 50 position of the material in these pieces as it ex drawing for feeding box ends into an automatic isted in the log. This circumstance often re box making machine is, with the exception of suits in such adjacent vpieces having a com the new parts therein embodying the present in mon knot hole extending through the two pieces. vention, shown and described in the aforesaid 55 Sometimes a section of the knot becomes loose Northrup patent, the disclosure in the North 55 2 2,118,530 rup patent will, to simplify the present specifica tion, be embodied therewith by reference. For convenience the letter E will be used to designate said box end feeding mechanism and the letter N to designate the nailing machine with which this feeding mechanism is embodied. Attention will ñrst be directedto the old parts of the mechanism E by use of the same reference characters by which these parts are identified in 10 the aforesaid patent. Thus it is seen that the> mechanism E is supported on frame 2 of the nailing machine N and carries a stack of box ends 6 which individually are disposed vertically, the stack itself being echeloned by the fact that 15 it is supported in a downwardly sloping hopper 1. The box ends 6 are adapted to be fed forwardly |30 is mounted for idle rotation. The clutch |3| also includes a sleeve |33 which surrounds the clutch base |32 and is integral with the sprocket |30. Sleeve |33 has a tube |34 extending radially therefrom this tube having a cap |35 through which a plunger |36 extends. The plunger |36 has a head|31 on its inner end and a nut |38 on itsouter end and a spring |39 is coiled about the plunger |36 between the cap |35 and the head |31. Provided in the clutch base |32 is a recess 10 |40 into which a steel ball |4| is continually urged by contact of the head |31 with this ball under pressure of the spring |39. Being integral with the sprocket |30, the sleeve |33 and other parts mounted thereon rotate with 15 the Sprocket |30 as long as the power mechanism of the nailing machine N to which the chain 18 one at a time by a lug 14 which is pivotally sup ported on a vertical axis on a horizontally recip is connected, continues to function. This power rocating carriage Il, the movement of which is mechanism is run by an electric motor (not 20 imparted thereto by an arm I2 connected with the power mechanism of the machine N. The carriage || in each of its horizontal reciproca tions feeds slats into the machine for forming one of the sides or the bottom of the box being 25 assembled in the nailing machine N, but only one set of box ends 6 is required during all three of these side and bottom assembling operations. It is necessary, therefore, for the carriage || to make three horizontal reciprocations and feed 30 a set of box ends 6 into the assembling appa ratus of the nailing machine N only during the first of each such group of three reciprocations. To prevent the feeding of box ends 6 excepting during the first of each group of three slat feed 35 ing reciprocations by the carriage I I, the box end hopper 1 is provided with a forward plate 1a which guides the box ends 6 as they slide down wardly in the hopper 1 toward the lug 14 so that the rear edges of the ends 6 are disposed to the 40 L: rear of the forward edge of the lug 14 when the carriage I I is in its rearwardmost position. This relationship between the box ends 6v and the lug 14 effectively prevents the feeding of a box end from the` hopper 1 excepting when the foremost 45 .i box end 6 is fed forwardly a sufficient distance so that its rear edge is in advance of the front edge of the lug 14 thereby permitting the latter to be swung by its spring 14a behind the foremost box en_d 6 so that upon the next forward move lment of the carriagevII the lug 14 thereon will feed this foremost box end 6 into the assembling mechanism of the machine N. , , To accomplish this initial feeding movement of the foremost of the box ends 6 so that one of 55 these box ends is fed forwardly lby each third shown) the circuit of which, in this invention, 20 includes a switch _|50 which is adapted to be acuated by a control arm |5I, the latter being connected by a link_,|52 to a cam arm |53, the other end of the latter arm being pivoted at |54 to the frame 2. The cam arm |53 has a curved portion, |55 the. curvature of which is formed about the axis of the shaft 11 with a radius just slightly longer than that at which the outer ex tremity of the plunger |36 normally revolves. When the box making machine N is operated to make a box the box ends 6 are advanced one at a time by the lever 15 so as to be fed forwardly by the carriage I | with each set of slats for form ing the first side to be assembled with the box. In case the foremost of the box ends 6 in the magazine 1 were for some reason to jam, as would be the case if they were keyed together by a loose knot in a common knot hole, there would be such a resistance setup to the forward move ment of the lever arm 15 by the cam 16 that the 402 torque clutch base |32 would be held still with the shaft 11 and the steel ball |4I would be forced from the recess |40 by the increased torque set up between the sleeve |33 and the clutch 45.. base |32. The angular relation of the clutch tube |34 to the cam arm 16 when the ball I4| is located in recess |40 is as illustrated by the full line posi tions of these elements in Figs. 1 and 3. In the event of the jamming of the Vforemost box end 56:1 6 in the magazine 1 and the dislodging of the ball |4I from the recess |40, a radial outward move ment of this ball would result which pushes the plunger |36 outwardly, as shown in its dotted line position |10 in Fig. 3. Although still rotat forward movement of the' carriage II, a lever 15 ing with the sprocket wheel |30 the plunger |36 is pivotally mounted on the frame 2 and this lever is moved by a cam arm 16 on a shaft 11. is, by its outward movement, caused to lift cam arm |53 thereby swinging the switch arm |5| from its full line position in Figs. 1 and 3 to its broken line position in Fig. 3 which opens the switch |50 and stops the power mechanism which drives the nailing machine N. Thus the entire which is rotated by a chain 18 one revolution for 60 each three reciprocations of the carriage I I. The rotating of the shaft 11 is so timed by the man ner in which the chain 18 is connected to the power mechanism of the nailingmachine N that a box end 6 is fed forwardly into its dotted line 65 position 6a just in time to be caught by the lug 14 as the carriage || starts forward to feed the side slats into the machine for forming the first side of a box. The parts described hereinabove are old in the 70 aforementioned Northrup patent, the addition to the art provided by the present invention being described as follows. Chain 18 is connected to the shaft 11 through a sprocket |30 with which is embodied a torque clutch |3|. This torquev 75 lclutch includes a base |32 on which the sprocket machine is stopped automatically and without the intervention of the operator and without there being any necessity for his even observing the 65 jamming of the box ends 6. The stopping of the machine of course immedi ately calls itself to the operator’s attention. When upon examination he discovers the source of the trouble it is only necessary to lift the jammed box ends 6 from the hopper 1, reset the clutch |3| by seizing thecam arm 16 and rotating this into the position which it would have had if the jamming had> not occurred and then imme diately start the machine to continue with the 754 2,113,530 manufacture of boxes. It is thus seen that a resumption of full automatic operation of the nailing machine N after being interrupted by a jamming of the box ends when this machine is equipped with my invention is an extremely simple and short process compared with the ardu ous repairs formerly needed before operations could be resumed. It is also apparent that when the nailing ma 10 chine N is equipped with my invention the need for the operator constantly observing the func tioning of the two box end feed devices E on the machine is done away with as with my invention the operator may depend upon it that Whenever 15 any jamming of these box ends occurs it will be called to his attention immediately by the Stop ping of the machine. While the drawing of this application does not show the entire Northrup machine, it is to be 20 understood, as previously mentioned, that the Northrup patent disclosure is included by refer ence in the disclosure of this application. It is also to be understood that the scope of this in vention is not to be considered as limited to the 25 specific embodiment illustrated herein, as the safety device of my invention is not only appli cable to a mechanism for feeding box ends into an automatic box making machine, but is also applicable to the feeding of the slats into such 30 machine for forming the sides and bottom, of the box. It is further applicable to the controlling of individual mechanisms in various machines in which a plurality of mechanisms is operated by a unitary power means for cooperatively achieving a single result. One of the particular advantages of this inven tion is that the individual mechanism is protected from being damaged by the power means of the 3 machine, when the individual mechanism jams, by the severing of the drive connection with this mechanism and at the same time the destructive operation of the other mechanisms in the ma chine, while the jammed mechanism is stopped, is prevented by the automatic stopping of the uni tary power means, which in this case is the motor driving the machine. What I claim is: , 1. In a box nailing machine, the combination of: means for transmitting an initial feeding movement to a box part to start the feeding of Said part into proper relation for assembly with other box parts; power means for actuating said feeding means; a torque clutch connecting said feeding means and said power means, said clutch being automatically disengaged when thetorque required for the operation of said feeding means rises above a given value; and means for stopping the operation of said machine, said means being responsive to the throwing out of said torque clutch to stop said machine. 2. In a box nailing machine, the combination of: power means for operating said machine; means for transmitting an initial feeding move ment to a box part to start the feeding of said part into proper relation for assembly with other box parts, said means including a shaft, a torque clutch mounted on said shaft and said power means, said torque clutch automatically opening 30 to disconnect said power means from said shaft when the torque transmitted through said clutch rises above a given value; means for stopping the operation of said power means; and means actu ated by said power means and responsive to the opening of said clutch to actuate said means for stopping the operation of said machine. HALE PAX'I‘ON.