US3210072A

US3210072A - Blank feeders for folding box machines

Info

Publication number: US3210072A
Application number: US319716A
Authority: US
Inventors: Thomas R Baker; Jr Chester J Pierce
Original assignee: BRADFORD SPEED PACKAGING AND D
Current assignee: BRADFORD SPEED PACKAGING AND D; BRADFORD SPEED PACKAGING AND DEVELOPMENT CORP
Priority date: 1963-10-29
Filing date: 1963-10-29
Publication date: 1965-10-05
Anticipated expiration: 1982-10-05
Also published as: DK115906B; SE307885B; GB1011180A

Description

Oct.5, 1965 M KER ETAL 3,210,072

' Filed Oct. 29', 1963 BLANK FEBDERS FOR FOLDING B OX MACHINES s Sheets-sheaf].

INVENTOR. Thomas R. flake/- Y Chesfer .1 fierce, Jr.

nu-MM ATTORNEY 'r. R- BAKER ETAL BLANK FEEDERS FOR FOLDING BOX MACHINES 6 Sheets-Sheet 2 Filed 00's. 29, 1963 INVENTOR. Thomas R. Baker Chesfer J. Pierce, Jr.

W ATTORNEY 1965 'r. R. BAKER ETAL 3,210,072

BLANK FEEDERS FOR FOLDING BOX MACHINES Filed Oct. 29,1963 e Sheets-Sheet s INVENTOR. Thomas R. Baker Chesfer J. Pierce, Jr.

#v-w-ML M 194.41 A TTORNEY Dot. 5, 1965 'r. R. BAKER ETAL 3,210,072

BLANK FEEDERS FOR FOLDING BOX MACHINES Filed Oct. 29; 1963 6 Sheets-Sheet 4 INVENTOR. 7/10/1705 A. Baker BY Chesfer J Pierce, Jr.

w ATTORNEY Oct; 5, 1955 1-. R. BAKER ETAL Filed Oct. 29, 1963 6 Sheets-Sheet 5 mmummmmnmmnunmmllllllilllIIHIJ-IIJIIIIIIIIIIEI ll -II" N I I 3 an 1 In. i

mmm mm Fig. 6

INVEN TOR. T/mmas R. Baker BLANK FEEDERS" FOR FOLDING BOX mcnmms Oct. 5,1965 T. R. BAKER ETAL 3,210,072

BLANK FEEDERS FOR FOLDING BOX MACHINES Filed Oct. 29, 1963 6 Sheets-Sheet 6 Fig.7 7

INVENTOR. Thomas R. Baker Chesfer J. Pierce, Jr.

BY WW ATTORNEY 3,210,072 BLANK FEEDERS FOR FOLDING BOX MACHINES Thomas R. Baker, Los Altos, and Chester J. Pierce, Jr., Palo Alto, Calif., assignors, by mesne assignments, to Bradford Speed Packaging and Development Corp., New York, N.Y., a corporation of Delaware Filed Oct. 29, 1963, Ser. No. 319,716 9 Claims. (Cl. 271-30) This invention relates to improvements in blank feeders of .the type in which a periodically operated blank transport means fitted with one or several suction cups removes individual folding box blanks through the withdrawal gate of a magazine containing a stack of blanks.

The magazine gate comprises appropriate means, for example one or several lips which marginally overlie the foremost blank of the stack, for preventing the blank from dropping out under the pressure of the stack of blanks behind it. The foremost blank is distorted or flexed when the suction cup of the transport means attaches itself to the blank and begins to pull it away from the stack, the degree of flexing or distortion being sufficient for the blank to clear the retaining element or elements.

Blank magazines are known in which the stack is vertical, or nearly so. The disadvantage of this arrangement is that the force required for withdraw-a1 of the foremost blank varies in direct proportion to the height of the stack. The permissible height is generally low and must be kept within close limits to insure proper feeder operation. This, in turn, requires frequent reloading of the magazine.

Magazines are alsoknown in which the stack is nearly horizontal or slightly inclined. This arrangement offers ,theadvantage that the pressure of the stack on the magazine gate varies little with the height, or rather length, of the stack. A greater number of blanks may therefore be loaded at one time into a blank magazine of the latter type. The running time of the box machine between periods of reloading is long, and one operator can supervise a greater number of machines than in the case of vertical stacks.

Blank feeders with horizontal or slightly inclined magazines have undergone considerable refinement to eliminate the friction between the blanks and the magazine. It

is known in this connection to rest the blanks on ,edge or cylindrical rods which are either rotated or oscillated to reduce friction. This, however, isnot enough to cause the stack to advance towards the gate where blanks are continuously being withdrawn. It has therefore been necessary to employ a pusher, also called follower, at the back of the stack to push the stack towards the gate, either by the force of a spring pulling the pusher towards the gate, or by a pull-cabIe-and-weight arrangement. the latter offering the advantage of exerting a forceof equal magnitude for close and distant positions of th pusher with respect to the gate.

The presence of a pusher is a considerable inconvenience in reloading the magazine, as the pusher must be separated from the rearmost blank in the stack to permit a batch of blanks to be inserted in the space so created.

During the period of separation of the pusher from the stack of blanks in the magazine the pressure on the magazine gate is greatly diminished and misfeeding may result from failure of the blanks to advance properly.

In addition, the entire reloading operation is awkward for the operator who needs both hands to handle the new batch of blanks to be inserted.

According to the invention the need for a pusher is eliminated, 'so that a magazine of great blank capacity may be reloaded at anytime and without inconvenience. The invention is based on the discovery that there is a range of inclinations of the magazine rods within which range the weight of the blanks is sufiicient to cause the blanks to advance towards the gate under the action of gravity, yet the angular inclination is small enoughso as not to result in an appreciable dilference in pressure on the gate between the condition in which the magazine is almost empty and the stack is short, and the condition in which the magazine is fully loaded and the stack is long.

The invention further deals with the problem which arises from the pounding of the oscillating blank transport means against the front end of the stack. In pusherequipped magazines the pounding causes no difiiculties, but in a pusherless assembly there -is the danger that the pounding causes the blanks in a short stack to be knocked over into the fiat and shingled position on the supporting rods, in which position they cannot be grasped by the suction cup and also fail to advance.

The invention will appear more fully from the detailed description which follows accompanied by drawings showing, for the purpose of illustration, a preferred embodiment of the invention. The invention also resides in certain new and original features of construction and combination of elements hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to be novel will be particularly pointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it may be carried out may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of it in which:

FIG. 1 is a perspective view of a blank magazine and transport mechanism embodying the invention;

FIG. 2 is a perspective closeup view of a portion of the mechanism of FIG. 1;

FIG. 3 is a perspective view of the magazine gate portion of the device;

FIG. 4 is an elevational view showing adetail of the blank transport mechanism;

FIG. 5 is a perspective view of the magazine operating mechanism underneath the rear portion of the magazine;

FIG. 6 is a perspective view of another portion of the operating mechanism; and

FIG. 7 is a perspective closeup view of the magazine gate and a short stack of blanks illustrating a specific operating condition.

In the following description and in the claims various details will be identified by specific names for convenience. These names, however, are intended to be generic in their application. Corresponding reference characters refer to corresponding parts in the several figures of the drawings.

The drawings accompanying, and forming part of, this specification disclose certain specific details of construction for the purpose of explanation of broader aspects of the invention, but it should be understood that structural details may be modified in various respects without departure from the principles of the invention and that the invention may be incorporated in other structural forms than shown.

The folding box machine shown in FIG. 1 comprises a machine base or frame 11 on which a magazine gate 12 is mounted at 13 and 14. Four

rods

15, 16, 17 and 18 extend rearwardly from the gate 12 and are supported in a rear bracket 19 on the machine base 11.

The

inner pair

15,16 of the rods are rotatably mounted on the gate 12 and the rear bracket, respectively, and support a stack 20 of folding box blanks B which rest on the

rods

15, 16 on edge.

The outer pair of

rods

17, 18 lie slightly above the

rods

15, 16, are stationary, and engage the blanks B laterally, so as to keep them lined up (see also FIG. 2).

The gate 12 is fitted with lip elements 21 marginally overlapping the leading surface of the foremost blank adjacent its upper edge, and lateral lip elements 22 which marginally overlap the foremost blank at its lateral edges .in' order to prevent the blank from dropping out of the magazine gate under the pressure of the stack of blanks behind (see also FIG. 3

A reciprocating blank transport means is provided for grasping the foremost blank of the stack 20 and pulling it out of the gate past the retaining lips 21, 22. In the illustrated form of device the transport means comprise two vacuum cup assemblies 23 mounted on a common mounting plate 24 which, in turn, is secured to an arm 25 on an oscillating shaft 26 to'which the arm 25 is keyed at 27 and clamped at 28. A flexible vacuum line 29 extends to the suction cups and applies vacuum at regular intervals, as is known in'the art (see FIG. 4).

FIG. 2 shows the transport means at the moment of engaging and withdrawing a blank, FIG. 1 shows the transport means in the act of moving the withdrawn blank .gate,'as blanks are being removed therethrough.

For this purpose the inclination of the rods angle a was varied, and it was found that for inclinations exceeding degrees the pressure produced by the weight of the stack on the retaining lips on the gate becomes so great when the stack is long, ortall, as to interfere with the proper removal of blanks, Furthermore, the pressure varies too greatly, depending on the size of the stack, to make the operation dependable. At the other end of the range it was found that an inclination of less than 15 degrees causes unreliable advance-of the stack in spite of agitation of the

rods

15, 16. The range of 15 to 40 degrees was found to be satisfactory for large as well as short stacks'of blanks and no feeding difficulties are encountered. The-absence of a pusher. or follower at the rear of the stack is a great improvementand convenience in that a great number of blanks may be loaded at once without interference by, or need for removal of, a pusher.

The 15 to 40 degree tilt permits long operating periods without supervision.

In the event the stack is permitted to become nearly exhausted. before reloading, a condition arises in which the pounding of the reciprocatingtransport means causes the rearmost blanks to be tipped over- This condition is .shown in'FIG. 7.

towards a conveyor 30 which is of no further importance in considering the present invention and improvement, and FIG. 3 shows the transport meansat about the end of its withdrawal stroke, which is the beginning of its return stroke toward the magazine.

The inner pair of

rods

15, 16 which support the weight of the blanks is agitated for the purpose of reducing the friction between the blanks of the stack and the rods.

To this end the-rods are given-a rotary motion about their axes. It is sufficient to limit the rotation to a fraction of one revolution, in other words, it is sufiicient to oscillate the rods through a predetermined are.

As seen in FIG. 1, an arm 31 is attached to the rod 15 near its upper end and a link 32 extends from the arm 31 to a further arm 33 on an oscillating square bar 34 pivotally-mounted at 35. A similar arm and link assembly connects the rod 16 with the oscillating bar 34, but is obscured in FIG. 1 by the stack of blanks 20.

Another arm is connected to the square bar 34 at 36 (FIG. I). The other end of the arm is seen at 37 in FIG. 5. A connecting rod 38 extends from the lower portion of 37 of the arm to a pendulous lever 39 secured to a transverse shaft 40 in the machine base. A connecting rod 41 leads from the end of the lever 39 to a crank 42 on a rotating shaft 43.

As the crank 42 is rotated, the lever 39 moves back and forth in a pendulous fashion and causes the blank trained over a sprocket gear 46 on the shaft 43. The

shaft is supported in a bearing 47 on a mounting plate 48 and carries an outer crank 49 from which a connecting rod 50 extends to an arm 55 on the keyed shaft 26 which carries the blank transport assembly including the suction cups 23. k

As the chain 45 is driven, the shaft 26 oscillates,-the suction cups 23 move back and forth, the shaft 43 ro- Means may be provided for'retaining the blanks upright. Basically the means comprises a catch or finger element which is movable either into one position to engage a blank adjacent an edge, preferably the top edge at the trailing surface of the blank, or into another position in which it clears the blank. The movement of the element is controlled in dependence on the presence or absence of blanks rearwardly, i.e., upstream,.of the catch or finger. Thus the device comes into operation when the stack of blanks becomes short which is the condition in which the danger arises of blanks being tipped over, as shown in :FIG. 7.

'A representative form of assembly is shown in FIGS. 13. The catch proper or tip of the arresting finger is the end 51' of a flat spring havinga body portion 52 and a mounting end 53 at which it is secured to .a bracket 54 attached to the gate 12 and exending rearwardly of the gate over-the magazine rods and the stack '20 of blanks thereon.

As seen in FIG. 2, the spring, when relaxed, assumes a position in which its free end or tip 51 lies behind the trailing surface of the last blank of the stack adjacent the top edge of the blank. Pounding of the reciprocating blank transport means cannot knock the blanks over, as they come to rest against the catch finger 51. If the magazine is reloaded, blanks upstream of the tip 51 engage the body portion 52 and deflect the catch into disengaged position (FIGS. 1 and 3). In this condition the mass of the long stack ofblanks is sufiicient to absorb the pounding of the blank transport means without danger of blanks tip ing over.

What is claimed i5;

1. 'A pusherless blank magazine and feeder for folding box machines, comprising, in combination, a pair of blank supporting rods of circular cross section adapted to support a stack of blanks resting on the rods on edge, the rods having an inclination to the horizontal of not less than 15 and not more than 40 degrees; means for agitating the rods about their axes; a magazine gate at the lower endof the rods including lip'mcans for marginally overlying, and retaining, the foremost hlunk of the stack in the gate against dropping out under the force of gravity; a reciprocating blank transport means comturn stroke the foremost blank and withdrawing the said blank during the subsequent feed stroke; and a barb type catch above said rods in advance of said gate for engaging, and retaining upright, blanks closer to the gate than the position of said catch.

2. A pusherless blank magazine and feeder for folding box machines comprising, in combination, a pair of blank supportingrods of circular cross section adapted to support a stack of blanks resting on the rods onedge, therods having an inclination to the horizontal of not less than and not more than 40 degrees; means for agitating the rods about their axes; a magazine gate at the lower end of the rods including lip means for marginally overlying,.and retaining the foremost blank of the stack in the gate against dropping out under the force of gravity; a reciprocating-blank transport mean-s comprising a suction cup for engaging .at the end of its return stroke the'foremost blank and withdrawing the said'blank during the subsequent feed stroke; a catch mounted above said rods in advance of said gate for marginally engaging the top edge of blanks on said rods, said catch being movable into and out of blank-engaging position; and means operable by blanks on said rods ata distance from said gate greater than the distance from the catch to the gate formoving said catch into disengaging position.

3. A pusherless blank magazine and .feeder for folding box machines comprising, in combination, a pair of blank supporting rods of circular cross section adapted to support a stack of blanks resting on the rods on edge, the rods'having an inclination to the horizontal of not less than 15 and not more than 40 degrees; means for agitatingthe rods about their axes; a magazine gate at the lowerend of the rods including lip means for marginally overlying, and retaining, the foremost blank of the stack in the gate-against dropping out under the force of gravity; a reciprocating blank transport means comprising a suction 'cup for engaging at the end of its return stroke the foremost blank and withdrawing the said blank during the "subsequent feed stroke; a movable catch mounted above said rods at a certain distance from said gate for engaging the trading surface of a blank on said rods adjacent its upper edge; means for biasing said catch into blank engaging position; and means responsive to the presence of blanks on said rods at a distance from said gate greater than said certain distance for moving said catch into disengaging position.

4. A pusherless blank magazine and feeder for folding box machines comprising, in combination, a pair of blank supporting rods of circular cross section adapted to support a stack of blanks resting on the 'rods onedge,

- the'rods having an inclination to the horizontal of'not less than 15 and-not more than 40 degrees; means for agitating the rods about their axes; a magazine gate at the lower end of the rods including lip means for marginally overlying, and retaining, the foremost blank 'of the stack in the gate'against dropping out under the force of gravity; a reciprocating blank transport means comprising a'suction cup 'for engaging at the end of its re turn stroke theforemost blank and withdrawing the said blank during the subsequent feed stroke; a movable finger mounted above said rods in advance of said gate, said finger pointing towards the gate, its tip being spaced from the'rods less than the height of the blanks when extended and more than the height of the blanks when the finger is retracted; and means responsive to the presence and absence, respectively, of blanks on said rods in advance of said'tip for retracting and extending, respectively, said finger.

5. A pusherless blank magazine and feeder for fold- .ing box machines comprising, in combination, a pair of blank supporting rods of circular cross section adapted to'support a stack of blanks resting on the rods on edge, the rods having an inclination to the horizontal of 'not less than 15 and not more than 40- degrees; means for agitating the rods about their axes; a magazine gate at the lower end of the rods including lip means for marginally overlying, and retaining, the foremost blank of portion adapted to engage the rear surface of a blank on the said rods, and a body portion adapted to be engaged by blanks present on said rods at a distance greater than the distance of the said tip portion from the gate,

for deflecting the finger into blank clearing position when said body portion is so engaged.

6. A pusherless blank magazine and feeder for folding box machines comprising, in combination, a pair of blank supporting rods of circular cross section adapted to support a stack of blanks resting on the rods on edge, the rods having an inclination to the horizontal of not less than 15 and not more than 40 degrees; means for agitating the rods about their axes; a magazine gate at the lower end of the rods including lip means for marginally overlying, and retaining, the foremostblank of the stack in the gate against dropping out under the force of gravity; a reciprocating blank transport means comprising a suction cup for engaging at the end of its return stroke the foremost blank and withdrawing the said blank during the subsequent feed stroke; a bracket extending rearwardly from said gate over said rods; and a flat spring mounted on said bracket to point with its free end toward said gate, said spring being adjusted resiliently to snap behind the top edge of the terminal blank of a stack which has moved beyond the spring in its travel towards the gate, and to be deflected into blank clearing position when engaged by blanks at portions of the spring in advance of the free end of the spring.

7. A pusherless blank magazine and feeder for folding box machines comprising, in combination, a pair of blank supporting rods of circular cross section adapted to support a stack of blanks resting on the rods on edge, the rods having an inclination to the horizontal of not less than .15 and not more than 40 degrees; means for agitating the rods about their axes; a magazine gate at the lower end of the rods including lip means for marginally overlying, and retaining, the foremost blank of the stack in the gate against dropping out under the force of gravity; a reciprocating blank transport means comprising a suction cup for engaging at the end of its return stroke the foremost blank and withdrawing the said blank during the subsequent feed stroke; anda flat spring mounted above said rods to extend with its free end toward said gate, said spring being adjusted to clear blanks thereunder when deflected by such blanks and to 'move by resiliency into a position in which it snaps behind the top edge of a terminal blank of a stack, when said terminal blank has cleared the free end of the spring.

8. A pusherless blank magazine and feeder for folding box machines comprising, in combination, a pair of blank supporting rods of circular cross section adapted to support .astack of blanks resting on the rods on edge, the rods having an inclination to the horizontal of not less than 15 and not more than 40 degrees; means for agitating the rods about their axes; a magazine gate at'the lower end of the rods including lip means for marginally overlying, and retaining, the foremost blank of the stack in the gate against dropping out under the force of :gravity; and a'reciprocating blank transport means comprising a suction cup for engaging at the end of its return stroke the foremost blank and withdrawing the said 'blank during the subsequent feed stroke.

9. A pusherless blank magazine and feeder for folding box machines comprising, incombination, a pairof blank supporting rods of circular cross section adapted to sup- 7 8 rods having an inclination to the horizontal of not less means for oscillating said rods and'reciprocating said than 15 and not more than 40 degrees; means for osciltransport means in timed relationship. lating the rods about their axes; a magazine gate at the lower end of the rods including lip means for margin- Refel'emes Cited y Examine! ally overlying, and retaining, the foremost blank of the 5 UNITED STATES PATENTS stack in the gate against dropping out under the force of gravity; a reciprocating blank transport means com- 523 1;: 2 5 15 prising a suction cup for engaging at the end of its re- 3l30'967 4/64 Bren turn stroke the foremost blank and withdrawing the said blank during the subsequent feed stroke; and power 1 M. HENSON WOOD, JR, Primary Examiner.

Claims

1. A PUSHERLESS BLANK MAGAZINE AND FEEDER FOR FOLDING BOX MACHINES, COMPRISING, IN COMBINATION, A PAIR OF BLANK SUPPORTING RODS OF CIRCULAR CROSS SECTION ADAPTED TO SUPPORT A STACK OF BLANKS RESTING ON THE RODS ON EDGE, THE RODS HAVING AN INCLINATION TO THE HORIZONAL OF NOT LESS THAN 15 AND NOT MORE THAN 40 DEGREES; MEANS FOR AGITATING THE RODS ABOUT THEIR AXES; A MAGAZINE GATE AT THE LOWER END OF THE RODS INCLUDING LIP MEANS FOR MARGINALLY OVERLYING, AND RETAINING, THE FOREMOST BLANK OF THE STACK IN THE GATE AGAINST DROPPING OUT UNDER THE FORCE