US3889450A

US3889450A - Methods and apparatuses for making strips of nails for use in nail driving tools

Info

Publication number: US3889450A
Application number: US305419A
Authority: US
Inventors: Claes Otto Sigfrid Danielson; Claes-Goran Staffan Andersson; Hans-Ake Christian Gram
Original assignee: HELSINGBORGS SPIKFABRIKS AB
Current assignee: HELSINGBORGS SPIKFABRIKS AB
Priority date: 1972-11-10
Filing date: 1972-11-10
Publication date: 1975-06-17
Anticipated expiration: 1992-06-17

Abstract

The invention relates to an improved method of making strips of fasteners disposed between and adhesively bonded to at least two opposed parallel tapes, especially simplifying guiding and gripping of the fasteners during operation such that the fasteners, when in the tape applying station, are properly oriented with respect to their angle of inclination and, for the production of strips of fluted fasteners, also with respect to the angular position about their longitudinal axis, all in a manner that in a substantial degree facilitates automatic production of such strips, and by using relatively simple equipment capable of giving high performance and eliminating operational breakdown.

Description

United States Patent n 1 Danielson et al.

[ June 17, 1975 [22] Filed: Nov. 10, 1972 [21] Appl. No.: 305,419

Baum et al.. 53/35 Hein 214/6 FS 3,422,968 l/1969 Martin 214/6 D 3,432,985 3/1969 Halstead..... 53/200 3,616,083 10/1971 Mohr.......... 53/196 X 3,707,425 12/1972 Jamal 156/552 X 3,729,885 5/1973 Mosetitch et al. 53/3 3,736,198 5/1973 Leistner 53/3 X Primary Examiner-Travis S. McGehee Assistant Examiner-John Sipos [57] ABSTRACT The invention relates to an improved method of mak ing strips of fasteners disposed between and adhesively bonded to at least two opposed parallel tapes, especially simplifying guiding and gripping of the fasteners during operation such that the fasteners, when in the tape applying station, are properly oriented with re spect to their angle of inclination and, for the production of strips of fluted fasteners, also with respect to the angular position about their longitudinal axis, all in a manner that in a substantial degree facilitates automatic production of such strips, and by using relatively simple equipment capable of giving high performance and eliminating operational breakdown.

10 Claims, 14 Drawing Figures PATENTEDJUN 1 SHEET 5 FIGZD PATENTEDJUN 1 7 ms SHEET PATENTEDJUN 17 I975 SHEET mm k SHEET PATENTEDJUN 17 ms 1 METHODS AND APPARATUSES FOR MAKING STRIPS OF NAILS FOR USE IN NAIL DRIVING TOOLS This invention relates to a method of making strips of fasteners fixed parallel to and spaced regular distances from each other between tapes of paper, plastics or like material adhesively adhered to the fasteners which are of the type having a shank with a head at one end and a point at the other end and which are fed from a sup ply, arranged in a row with the shanks parallel and the points directed in the same sense and are delivered to a tape and adhesive applying station to which at least two tapes are fed from a supply of such tapes which are joined by adhesive in parallel relationship on either side of the row of nails.

For driving nails into various materials it is previously known to use relatively light-weight, usually hydraulically or pneumatically operated portable tools which are loaded with strips of nails of the above type, that is usually strips of nails comprising a row of nails between two paper tapes adhesively adhered on either side of the row of nails. These paper tapes hold the nails equidistantly spaced in parallel positions and with the points directed in the same sense. Earlier, the diameters of the nail heads were determinative for the minimum distance between the nails in these strips of nails, considering that the outermost nail in a strip of nails when driven in by means of the portable tool shall go free from the head of the adjacent nail in the strip of nails.

In such an arrangement the nails can be placed with the upper faces of the nail heads situated in the same plane, the shanks of the nails extending at right angles to the paper tapes adhered on either side of the row of nail shanks. From this arrangement one has turned to disposing the nails obliquely with respect to the tapes adhered thereto and with the nails head located in different, parallel and equidistant planes. A characteristic feature of this arrangement is that the nail head overlap, the head of the first nail in the strip of nails bearing with its edge against the shank of the subsequent nail in the strip below the head of said nail which in turn is disposed in a corresponding manner with respect to the following nail, and so on in the entire strip. By this arrangement the nails in principle can be placed with the shanks at a distance from each other that corresponds to the distance from the edge of the nail head to the shank of one and the same nail. The angle between the nail shanks and the longitudinal direction of the adhesive tapes is determined for practical reasons with due regard to the portable nail driving tool.

For making such strips of nails it is previously known to use continuously operating machines equipped with a conveying mechanism which is driven continuously to convey nails from an orienting and feed station to a tape and adhesive applying station in which paper tapes are continuously adhered by means of adhesive to the shanks of the continuously advancing row of nails. From this station the continuous strip of nails formed in this manner is moved past a cooling station in which the adhesive is caused to set, and then to a fault detecting and strip severing station in which strip sections of predetermined lengths are severed from the continuous strip of nails held together by tapes adhered thereto, whereupon the strip lengths are discharged for packing.

Prior art machines of this type are very complicated and consequently expensive. The complicated construction of the prior art machines is due to the difficulty of coordinating the operating phases of the work stations in such a way that the entire operation can be performed at a smooth rate without disturbances. If a disturbance occurs in some station this naturally affects the entire course of operation in the machine. Particu larly sensitive operations are that of feeding the nails to the tape and adhesive applying station in the exact orientation necessary during the adhering of the paper tapes to the nails, and that of holding the nails while simultaneously moving them in a continuous motion during the course of the tape applying operation. Moreover, the cutting of the continuous strip of nails into predetermined lengths and, as the case may be, ranging the severed lengths of strips of nails for packing constitutes an operation apt to be disturbed.

The main object of the present invention is to overcome the disadvantages outlined above by providing a method that enables simple, undisturbed and well coordinated operations to be effected by means of a continuously operating simple and inexpensive machine of reliable function.

Further objects of the invention are to permit making strips of wire nails of rectangular section (brads), which has not been possible in the prior art machines.

To this end, the fasteners are conveyed in the ranged position from the supply to, and are suspended in, an inclined guide so as to depend with free inclination and with downwardly directed points, whereby the angular position of the shanks with respect to the plane of the guide is determined by gravity, and the fasteners are conveyed in this position to the tape and adhesive applying station where they are grasped in turn of order, kept the desired relative distance apart, and fed in between the tapes likewise supplied to said station, while the fasteners are still retained in the inclined guide and the tapes are adhered along the row of fasteners in parallel with the guide, whereupon the resulting continuous strip of nails is advanced along the guide to a severing station and cut in a known manner into predetermined lengths which are transferred to a stacking station for packing.

According to the invention, the machine for carrying out the method described above of making strips of nails comprises means for orienting the fasteners into a row with the points facing in one and the same sense and with the shanks placed in an angle of or less relative to the longitudinal direction of the row, a tape and adhesive applying station for adhering said tapes on either side of the shanks, conveying means for conveying the fasteners arranged in said row to the tape and adhesive applying station which includes two tape unwinding means for rolling the adhesive tapes onto said shanks and two fixation means for holding the fasteners in a predetermined position during the tape and adhesive applying operation at the same time as the fasteners are continuously advanced to a severing station which includes cutting means for cutting the continuously fabricated strip of nails into predetermined lengths. The conveying means is an inclined guide which is adapted to support the row of fasteners freely suspended with downwardly directed points during conveyance of the fasteners up to and into the tape and adhesive applying station so that gravity determines the angle of inclination a between the fasteners and the guide which is adapted, in conjunction with the fixation means, to guide the fasteners in this inclined position in between the tapes supplied to the tape and adhesive applying station with the fasteners still situated in the inclined guide during adhering of the tapes to the shanks, the tape unwinding means for rolling the tapes onto the shanks of the fasteners with the same inclination in relation to the horizontal plane as the inclined guide preferably being connected to the guide.

The invention will be more fully described hereinbelow with reference to the accompanying drawings in which:

FIG. I in a heavily diagrammatic representation shows the method of making strips of nails;

FIG. 2A-2F together show a plan view of a machine for making strips of nails;

FIG. 3 is a diagrammatic perspective view of the tape and adhesive applying station in FIG. 28;

FIG. 4 is a longitudinal section taken on line IVIV in FIG. 2B and shows a nail distributing and holding wheel and a pressure roller in the tape and adhesive applying station;

FIG. 5 shows the tape and adhesive applying station in cross section taken on line VV in FIG. 28;

FIG. 6 is a horizontal section taken on line VlVl in FIG. 5;

FIG. 7 shows the feed assembly for the strips of nails in a cross section taken on line VIIIVIII in FIG. 2D;

FIG. 8 is a side view of the strip catching and strip stacking unit shown in FIG. 2F;

FIG. 9 shows a strip of nails immediately before discharge thereof from the machine.

In the nail strip making machine diagrammatically illustrated in FIG. I nails are fed from a supply of randomly oriented nails in a magazine I which is a known vibration feed means in which the nails from a randomly oriented stack are oriented during discharge by vibration caused by an electromagnetic vibration generator and transferred to a guide 2 with the points directed downwards and carried in this position to a conveying chute 3 which is illustrated in the form of two parallel bars spaced apart a distance that corresponds to the diameter or width of a nail shank. The nails are advanced along the conveying chute 3 suspended in a row 4 with the nail heads resting on the upper face of the chute to a tape and adhesive applying station 5 in which a paper tape 6 having two strands of molten thermoplastic resin 7 placed on it, is adhered to either side of the nail shanks which in this station 5 pass between two wheel and roller means advancing the nails at correct relative distances and in correct angular position and rolling out the tapes 6 onto the shanks of the nails at the rate at which the row of nails pass between the roller means. Immediately before application of the adhesive tapes the adhesive strands 7 are molten by a heating device 8. After the passage of the row of nails between the roller means the adhesive strands are cooled to a set state by a cooling device 9. The strip of nails 4' made in the tape and adhesive applying station 5 is pulled forward by a feed assembly 10 along the conveying chute 3 and transferred to a severing station II in which the continously advanced strip of nails is cut into predetermined lengths which are fed from the chute 3 into a strip catching and stacking station 12 partly shown in FIG. 2F on section line 2F-2F in FIG. 8.

The above mentioned work stations are shown more in detail in plan view in FIGS. 2A-2F. As already mentioned, the vibration feeder 1 is an apparatus of a known type for feeding nails from a randomly oriented stack to a peripheral chute 2 which as shown in FIG. 2A is connected to the conveying chute 3 which is formed by two bars 3a. According to the invention, gravity and the inclination of the conveying chute 3 (which is adjustable) in relation to the horizontal plane is exploited to determine the angle of the nail shanks to an assumed plane extending through the nail heads or nail points in the row of nails, that is in FIG. 9 the angle a between the nail shanks and the tapes 6 applied in the tape and adhesive applying station and adhered in parallel with the bars 3a. This simplifies the introduction of the nails in correct position into the tape and adhesive applying station 5 and permits a simple setting of the angle between the nail shanks and the longitudinal direction of the tapes 6 adhered thereto in that the chute 3 has one of its ends pivotally mounted in the machine frame.

In FIG. 2A there is shown at 15 a magnetic type sensing means which is mounted on the bars 3a and which magnetically senses the presence of nails in the chute and is adapted, via electrical leads 16, to sense a feed pulse to the vibration feeder I if the sensing means senses a condition in which no more nails are advanced in the chute beneath it. A sensing means 17 in the form of a photoelectric cell assembly is mounted on the rails 3a in a position between the sensing means I5 and the tape and adhesive applying station 5. This sensing means 17 is arranged so as to have its photoelectric cell sense the height position of the nail heads on the bars 30. If for some reason a nail head has been caught on the heads of two adjacent nails this may disturb the op eration of the tape and adhesive applying station. The sensing means upon arrival of such a wrongly positioned nail delivers an electrical signal and transmits it via electrical leads 18 to a solenoid valve (not shown) by which air is admitted to a cylinder 19 for moving a piston 19' between the nails in the row of nails 4 at the moment when the wrongly positioned nail arrives in the region of the piston 19. The piston 19' moves the nails apart and thus causes the wrongly positioned nail to fall into correct position. The two assemblies 17, 19 thus automatically correct wrong nail positions during the movement of the nails towards the tape and adhesive applying station 5. These two assemblies 17, 19 may naturally be replaced by equivalent means giving the corresponding result.

The nails are advanced along the conveying chute to the tape and adhesive applying station 5 by sliding along said chute. Said chute can be so arranged as to be given vibration pulses by means of a separate vibration generator or by means of the vibration feeder l to facilitate conveyance of the nails.

The tape and adhesive applying station 5 includes as main constituents two

wheels

20, 22 mounted for rotation in the machine frame 14 (see FIG. 5), and at least one of said wheels 20 has a configuration similar to a gear wheel in that its periphery is formed with obliquely cut grooves 21 which have a groove division corresponding to the distance between the nails 4 to be joined by means of the tapes 6. The angle between the grooves 21 and the longitudinal axis of the wheel 20 corresponds to the angle of inclination of the chute 3. The

wheels

20, 22 are adapted, upon arrival of the nails, to catch the shanks of the nails in turn of order and to move them into the groove 21 of the rotary wheel 20. The grooves 21 are so disposed as to extend, when they occupy the position opposite the nails 40, at right angles to the bars 3a in order to keep the nails in correct position during the adhering of the tapes 6. The order wheel 22 may have a smooth periphery and serves as a counterwheel for pressing the nails into the grooves 21 of the wheel 20 and for holding the nails in said grooves during the movements of the nails through the tape and adhesive applying station. The grooved wheel 20 is adapted to be driven in synchronism with two pulling rollers 23, 24 in the feed assembly which will be described later on.

In FIG. 3 the grooved nail fixation wheel and the smooth counterwheel 22 are shown holding a nail 4a which depends from the chute 3 in vertical position between two

tape pressure rollers

25, 26 which like the

wheels

20, 22 are mounted in the frame 14 on either side of the nails 40.

In FIG. 3 the nails are assumed to move towards the plane of the paper which is indicated by the arrows for the movement of the

wheels

20, 22 and the

pressure rollers

25, 26. The

nail fixation wheeIs

20, 22 are mounted each on one

shaft

27, 28, and coaxially with each

shaft

27, 28 there is carried beneath the respective wheel 20, 22 a

tape guide roll

29 and 30, respectively, over which a paper tape 6 with glue strands 7 applied to the outer side thereof is passed to the row of nails (represented in FIG. 3 by a nail 4a) and the

respective pressure roller

25, 26. Each nail 4a which moves in between the

nail fixation wheels

20, 22 and is grasped by them is held in correct position when the

pressure rollers

25, 26 press the adhesive tapes 6 to the shank of the nail. The advance of the nails and the tapes 6 through the tape and adhesive applying station, which is realized by the

wheels

20, 22 and the

rollers

29, 30, is aided by the feed assembly 10 which pulls forth the finished strip of nails with the aid of the two pulling rollers 23, 24 which are driven by an electric motor 31 (only diagrammatically shown in FIG. 1) via a chain transmission 32 which also drives the grooved nail fixation wheel 20 and the corresponding roller 29 and, if desired, also the smooth nail fixation wheel 22.

Already before the initiation of the operation the tapes 6 are extracted from tape rolls 35 (FIG. 2C) in the frame and moved in between the pulling rollers 23, 24 of the feed assembly 10, whereby pull power is exerted from the very beginning on the row of nails over the entire distance from the feed assembly 10 to the tape and adhesive applying station 5. As the tapes 6 are pulled forth two parallel strands 7 of adhesive are applied on each tape by means of a known adhesive applicator 36. As already mentioned the adhesive is a thermoplastic resin which is fed in molten condition through two nozzles one for each tape. This device will be more fully described later on.

The tape and adhesive applying station 5 includes a guide member 38 (FIG. 3) which is mounted in an oblique position in the frame on the same side of the row of nails as the wheel 20 and serves to guide the nails in between the

fixation wheels

20 and 22 and the

pressure rollers

25, 26 in cooperation with a jet of air blown from a nozzle 39 disposed on the other side of the row of nails and connected to a source of air under pressure, directing the air jet towards the row of nails and the guiding member 38 to move the shanks of the nails apart so that they will readily fall one into each groove 21 of the wheel 20. As shown in FIG. 2B, the heating device generally designated 8 in FIG. 1 comprises two hot air blowing nozzles 40 disposed on either side of the row of nails 4 at the inlet side of the

pressure rollers

25, 26 by means of which nozzles the adhesive strands are heated to a suitable condition immediately before their arrival at the application point. The cooling device 9 also comprises two blowing nozzles 41 which are mounted on the outlet side of the

pressure rollers

25, 26 to blow cold air towards the adhered paper tapes whereby setting of the strands of adhesive is accelerated.

The smooth fixation wheel 22 is carried on the lower end of the shaft 28 provided therefor, which is movable towards the row of nails by means illustrated in FIGS. 2B and 5. These means include a frame 46 which is movable on two parallel guide rods 45 and carries a bearing housing 26 in which the shaft 28 has its upper end mounted. The frame 46 is spring-loaded towards the row of nails by two springs 47 on the rods 45. These springs are interposed between the frame 46 and a bar 48 which is connected at its ends to two sleeves 49 slidable on the guide rods 45. The bar 48 is connected to the frame 46 by means of a screw 50 which freely passes through the frame 46 against which it bears with a head formed as a hexagon nut 51, and is screwed into a threaded bore in the bar 48 against which a stop nut 52 bears. The bar 48 is further connected to a shaft 53 which is placed beneath the screw 50. The shaft 53 is movably mounted in a block 54 connected to the frame 14 and carries in a fork-shaped end portion a guide roller 55 which engages in an eccentrically arranged slot 56 in a sector-shaped disk 57 which is rotatably mounted on a shaft 58 and is operable by means of a handle 59. By rotation of the disk 57 by means of the handle 59 the shaft 53 can be moved in the one or other sense by engagement of the guide roller in the slot, and as a result of the frame 46 and the wheel 22 can rapidly be retracted to a free position with respect to the row of nails to facilitate access should the paper tapes rupture or other faults occur. In normal operating position the wheel 22 is preloaded by the springs 47 on the guide rods 45 towards the grooved wheel 20. The spring load is adjustable by means of the screw 50 in the manner that will be apparent without difficulty from the foregoing.

As is shown in FIG. 1 the

tape guide rollers

29, 30 mounted on the shaft 27 of the grooved wheel 20 and on a separate shaft 28' are vertically adjustable to permit changing the position for the application of the tapes 6 (omitted in FIG. 5) on the shanks 4a on the nails. To this end, the shafts 27, 28' in the area above the

columns

60, 61 in which they are mounted, are of a length considerably greater than the width of the

guide rollers

29, 30, and the guide rollers are movably mounted on the

shafts

27, 28. The shafts and the

rollers

29, 30 are formed with keyways 62 and are coupled by means of coupling keys 64 (see FIG. 4) so that specifically the wheel 20 can be rapidly exchanged for another wheel having other grooves 21. To fix the guide rollers in the height position set each guide roll has a threaded radial bore in which engages a fixation screw 63 which is countersunk in said bore so as not to damage the paper tape. The two

pressure rollers

25, 26 are mounted on arms 65, 66 which are pivotally mounted in fastenings 67, 68 on the

columns

60, 61 and are pivoted each to a spring loading device comprising a rod 69 which freely passes through a bore in a fastening 70 on the

respective column

60, 61 and is adjustable by means of a nut device 71 for changing the tension of a spring 72 which is interposed between the fastening 70 and a spring support at a head 73 on the rod 69.

FIG. 2C shows part of the frame between the tape and adhesive applying station and the feed assembly which carries the adhesive applicator 36 and an electric drive motor 80 for operation of an adhesive feed means. Via a chain transmission 81, an adjustable gearing 82 and a chain transmission 83 the electric motor drives the feed means 84 for pulling forth a strand of solid thermoplastic adhesive from a supply thereof.

The adhesive applicator 36 is of a known type. Therefore. it will not be necessary to describe this applicator in detail. It should be mentioned, however, that it includes a heating cabinet 88 and a device on which is carried a roll of adhesive strand in solid condition. This strand is pulled off the roll by the drive 80-83 and moved to a channel in the heating cabinet where the strand is molten by heat from one or more electric elements in the form of so-called heat cart-ridges 89. The molten resin adhesive is led through distributing channels 90 to two double nozzles 91 each delivering two parallel strands 7 (see FIG. 3) of liquid resin binder to each paper tape 6 at the point where said tape is pulled off the respective tape roll 35. When the tape is pulled off the respective roll 35 the tape is turned at 6' and then passes over a guide roller 92 (FIG. 2B) to a

corresponding guide roller

29, 30 beneath the wheel and 22, respectively, so that the strands of adhesive upon arrival at the tape and adhesive applying station 5 are facing the nail conveying path. Melting of the adhesive can be controlled automatically by means of a thermostat 93.

The entire adhesive applicator 36 in FIG. 2C is movably suspended in the frame by means of double acting cylinders 93 for shutting off the supply of adhesive.

FIGS. 2D and 7 show the feed assembly 10 for pulling forth the strip of nails 4 made in the tape and adhesive applying station 5. The feed assembly includes said pulling rollers 23, 24 which bear against the strip of nails 4' and are driven by the electric motor 31, and ad justable gearing 100 with slipping clutch, and a chain transmission 101 which may be part of the transmission 32 driving the grooved nail fixation wheel 20.

The drive shafts 102, 103 for the pulling rollers are rotatably mounted each in a hollow column 104 on the frame. Each of the two shafts carries at the lower end projecting from the frame 14 a sprocket wheel which is part of the chain transmission 101. In the embodiment illustrated one pulling roller 24 is not mounted directly on the main drive shaft but instead carried on the lower end of a vertical shaft 105 which is mounted in a bearing housing 106 supported on a horizontal arm 107. Said arm is pivotally mounted in a bearing in a bearing housing 108 on the upper end of the main shaft 102 in the manner clearly apparent from FIGS. 2D and 7 so as to permit being swung towards or away from the row of nails 4'. Moreover, the arm is connected by rod means 109 to a tension spring 110 which is connected to a lever system 111 by means of which the spring can be slackened to move the pulling roller aside. The spring tension is adjustable by means of a threaded bar and an adjusting nut 112. Driving power from the main shaft to the pulling roller 24 is transmitted by means of a sprocket wheel 114 on the main shaft beneath the bearing housing, a short chain 115 and a sprocket wheel 116 to the shaft 105 carried by the arm 107. As the arm can be swung about the center of the sprocket wheel and the main shaft the chain tension is not altered upon position changes of the arm.

If considered suitable or desirable the other main shaft and the corresponding pulling roller 23 can be mounted in the same way in the frame. In the embodiment illustrated it is possible not only to adjust the pressure of one pulling roller but also to swing said pulling roller completely away to permit access to the area of the row of nails. However, the embodiment illustrated has been chosen to ensure or facilitate centering of the pulling rollers with respect to the row of nails.

FIG. 2E shows a strip severing means which comprises a knife blade 120 fixedly mounted in the frame 14 on one side of the row of nails, and a guide 121 fixedly mounted on the other side of the row of nails and formed in its end with a slot containing a knife blade 120'. The knife blade 120' is movable towards the row of nails by means of a pneumatic cylinder 122 mounted in a holder in the frame and connected to a solenoid valve 123 which is electrically connected to a counter 124 and via this counter to a photoelectric cell unit 125. The photoelectric cell unit senses the arrival of the end of the strip of nails (not shown in FIG. 2E) and sends a pulse to the counter which then receives one pulse for each nail passing the photoelectric cell. After a given number of pulses corresponding to the desired number of nails the counter sends a pulse to the solenoid valve, the cylinder 122 being operated to sever the strip. Severing takes place with a short delay or by such a time adaptation of the pulse from the counter that the knife blade always cuts through the strip between two nails.

By a simple adjustment of the counter the severing means in FIG. 2E can be set for different lengths of strips of nails and different sizes of nails.

The strips of nails are passed along the chute 3, as for example under the influence of the force of gravity from the severing means in FIG. 2E to the strip catching and stacking station 12 in FIG. 2F. This station includes a strip catching means which is positioned at a lower level than the conveying chute and comprises two electromagnets 131 which are adapted to be energized every second time for catching the strip of nails 4" (FIG. 8) which they arrive at this station 12 and are allowed to fall from the chute between the two magnets. The magnets are supported by arms 132 which are connected to a turning mechanism which is driven by two pairs of double-acting

cylinders

133, 134 via a lever system. The

cylinders

133, 134 cooperate with one another and with a fifth cylinder 136 in the following manner.

The last section of the conveying chute 3' is separated (see FIG. 8) from the remaining part 3 of the chute and consists of two short bars 3a each of which is hung on the ends of one link in a linkage 140 which is carried by a frame 141 and is connected to the cylinder 136 (double-acting) by means of which the linkage is operable so as to move the rails 30' apart and together. The cylinder is controllable via a solenoid valve (not shown) which is electrically connected to a limit switch 143. When a strip of nails 4" arrives at the limit switch it delivers an opening pulse via the solenoid valve to the cylinder 136 which via the linkage 140 moves the bars 30 apart. The switch 143 is adapted, every second time it is operated by a strip of nails 4", to energize one magnet 131a and every second time the other magnet 131k for catching a falling strip of nails 4 when the bars 3a are opened. The magnet which is energized and catches a strip of nails is swung downward in that one of the two cylinders 133 in FIGS. 2F and 8 is activated and via the lever arm 13S lowers the magnet support arm 132. This will actuate one of the cylin ders 134 and said cylinder then rotates the magnet sup port arm through 90 via a crank arm system shown at 144, a limit switch 145 being actuated and breaking the circuit of the operated magnet 131a of 13115. In this way the strips of nails are deposited in a box placed beneath the turning mechanism described so that every second strip of nails is placed with the heads in one direction and every second strip of nails in the opposite direction, as is indicated in FIG. 8.

For fault detection fault sensing means, for instance of the photoelectric cell type, may be placed at points spaced along the conveying track. Such a fault sensing means can be combined with the severing means to order it to become operative when a defective nail strip portion is sensed, and in that case the severing means shall become operative to cut away the defective section. In this operation the limit switch 142 is disabled and thus allows the defective nail strip portion to pass for discarding. FIG. 9 shows a strip of nails 4" made in the machine. The angle a between the horizontal plane and the conveying chute 3 determines the angle a between a line at right angles to the longitudinal section of the tapes 6 and the shanks of the nails. By a simple alteration of the inclination of the nail conveying chute 3 and angle a can be altered to fit different nail driving tools. The chute may be pivotally suspended in the frame 14 at its lower end at a point 150 in FIG. 8, permitting the entire chute including the

work stations

1, 5, 10, ll, 12 to be swung about this point. Alternatively, the magazine and the chute may be pivoted to the frame 14 at the upper end for the same purpose. A simple operating means 115 can be arranged at the magazine for realizing the angular positioning of the chute. A further possibility is to make part of the frame 14 swingable in relation to a foundation.

As is apparent from the foregoing, the relatively complicated operations can be effected by means of a relatively simple machine the operating cycles of which are controlled and realized in a simple manner by mechanical transmission elements, electronic control means and pneumatic operating means. Particularly the advance of the nails to the tape and adhesive applying station implies an extraordinarily great simplification and the same can be said of the applying station proper with its fixation wheels, tape guide rollers and tape pressure rollers. A further essential advantage is that nails of rectangular section as well as of round section can be handled in the machine according to the invention and that an adjustment between different types of nails and sizes of nails can be effected in a short time and by simple changes.

We claim:

1. Apparatus for continuously producing strips of spaced fasteners, comprising in combination first guide means, means for continuously aligning individual fasteners in a row with the fasteners extending generally parallel to and spaced from each other, means for moving said aligned fasteners along a path determined by said first guide means tape applying and securing means for applying tape means in engagement with said aligned fasteners in the longitudinal direction of the row and for securing together said tape means and aligned fasteners for producing a web of fasteners fixed in space relationship by said tape means, means for moving said web along a path from said tape applying and securing means, to a cutting means, said cutting means cutting said moving web into individual strips, second means for moving said individual strips to a stacking station, the apparatus further comprising strip catching and stacking means located at said stacking station for catching each of said strips received from said second means and stacking it in a stack at said stacking station, said strip catching and stacking means being adapted to selectively release said strips and turn each released strip around an axis parallel with the longitudinal axis of said strip to stack every second strip on its right side and the other strips on their left side in said stack, wherein said strip catching and stacking means includes second guide means receiving said strips from said second means moving said strips, said second guide means being movably mounted to move between a first position supporting said strips within said second guide means and a second position wherein said strips are released to fall by gravity from said second guide means, and third means actuated by a one of said strips received in said second guide means and moving said second guide means respectively between first and sec ond positions.

2. Apparatus as defined in claim 1 wherein said third means includes a switch which is activated by contact with a one of said strips received in said second guide means and a double-acting cylinder connected to said second guide means and operating in response to sig nals received from said switch.

3. Apparatus as defined in claim 1 further comprising a pair of electromagnetic means rotatably disposed below said second guide means to be, in a first position, in the path of fall of said strips released from said sec ond guide means, said third means, when actuated, alternately actuating a one of said pair of electromagnetic means whereby said electromagnetic means, in said first position catches a strip falling in said path of fall, fourth means, actuated by said third means, said fourth means being operatively disposed with said pair of electromagnetic means and rotating, respectively, the one of said pair of electromagnetic means holding a strip through an angle of away from a medial plane of said second guide means to a second position and then releasing said strip to fall by gravity to the top of said stack, said fourth means, after release of said strip, returning said electromagnetic means to said first position.

4. Apparatus as defined in claim 3 wherein said fourth means includes a pair of cylinders operative associated with each of the said pair of electromagnetic means and moving said electromagnetic means, a second switch operated when said strip is rotated to said second position, said second switch, when operated, signalling said pair of cylinders to operate in a manner to return said electromagnetic means to said first position.

5. Apparatus as defined in claim 1 wherein said first and second guide means are adjustably mounted over a support base, which is generally horizonally disposed,

Claims

1. Apparatus for continuously producing strips of spaced fasteners, comprising in combination first guide means, means for continuously aligning individual fasteners in a row with the fasteners extending generally parallel to and spaced from each other, means for moving said aligned fasteners along a path determined by said first guide means tape applying and securing means for applying tape means in engagement with said aligned fasteners in the longitudinal direction of the row and for securing together said tape means and aligned fasteners for producing a web of fasteners fixed in space relationship by said tape means, means for moving said web along a path from said tape applying and securing means, to a cutting means, said cutting means cutting said moving web into individual strips, second means for moving said individual strips to a stacking station, the apparatus further comprising strip catching and stacking means located at said stacking station for catching each of said strips received from said second means and stacking it in a stack at said stacking station, said strip catching and stacking means being adapted to selectively release said strips and turn each released strip around an axis parallel with the longitudinal axis of said strip to stack every second strip on its right side and the other strips on their left side in said stack, wherein said strip catching and stacking means includes second guide means receiving said strips from said second means moving said strips, said second guide means being movably mounted to move between a first position supporting said strips within said second guide means and a second position wherein said strips are released to fall by gravity from said second guide means, and third means actuated by a one of said strips received in said second guide means and moving said second guide means respectively between first and second positions.

2. Apparatus as defined in claim 1 wherein said third means includes a switch which is activated by contact with a one of said strips received in said second guide means and a double-acting cylinder connected to said second guide means and operating in response to signals received from said switch.

3. Apparatus as defined in claim 1 further comprising a pair of electromagnetic means rotatably disposed below said second guide means to be, in a first position, in the path of fall of said strips released from said second guide means, said third means, when actuated, alternately actuating a one of said pair of electromagnetic means whereby said electromagnetic means, in said first position catches a strip falling in said path of fall, fourth means, actuated by said third means, said fourth means being operatively disposed with said pair of electromagnetic means and rotating, respectively, the one of said pair of electromagnetic means holding a strip through an angle Of 90* away from a medial plane of said second guide means to a second position and then releasing said strip to fall by gravity to the top of said stack, said fourth means, after release of said strip, returning said electromagnetic means to said first position.

5. Apparatus as defined in claim 1 wherein said first and second guide means are adjustably mounted over a support base, which is generally horizonally disposed, to be selectively disposed in a plurality of inclined positions with respect to said support base.

6. A device for stacking strips of fasteners fed from such apparatus for producing strips of fasteners fixed in spaced relationship by tape means as have guide means by which said produced strips are guided, said stacking device comprising strip receiving means for receiving, temporarily holding and releasing each strip fed from said apparatus through said guide means and a strip catching and stacking mechanism comprising rotatable supported means for catching each strip released from said receiving means, rotating means for turning said stacking means substantially 90* in opposite directions from a catching position around an axis substantially parallel with the longitudinal axis of each strip caught thereby to a stacking position such that every second caught strip is turned on its right side and the other strips on their left side, and means connected to said catching means and adapted to cause said catching means to drop said strips on a stack.

7. A device as defined in claim 6, whererin said strip receiving means comprising separable guide members defining a guide for receiving said strips fed from said guide means of said apparatus, said guide members being relatively movable between a first position supporting a strip received in said guide and a relatively separated second position for releasing said strip and permitting it to fall by gravity from said guide, operating means for moving said guide, operating means for moving said members relatively to each other between first and second positions and activating means adapted to be actuated by each strip received in said guide between said members and to actuate said operating means.

8. A device as defined in claim 7, wherein said activating means includes a switch adapted to be actuated by contact with each strip received in said guide and wherein said operating means comprises a double-acting cylinder connected to one of said guide members and adapted to operate in response to signals received from said switch.

9. A device as defined in claim 7 and further comprising a pair of electromagnetic means rotatably disposed below said guide defined by said members, each of said electromagnetic means having a first position close to the path of fall of said strips released from between said members when moved apart, said activating means being adapted, when actuated, to actuate said pair of electromagnetic means alternatively such that each of them in said first position catches every second strip falling in said path of fall, rotating means actuated by said activating means and operatively disposed with said pair of electromagnetic means to rotate, respectively, the one of said pair of electromagnetic means holding a strip through an angle of 90* away from a medial plane of said guide defined by said members to a second position and then releasing said strip to fall by gravity to the top of said stack, said rotating means, after release of said strip, returning said electromagnetic means to said first position.

10. A device aS defined in claim 9, where in said rotating means includes a pair of cylinders operatively associate with each of the said pair of electromagnetic means for moving said electromagnetic means between said first and second positions, a second switch operated when said electromagnetic means are rotated to said second position, said second switch, when operated, signalling said pair of cylinders to operate in a manner to return said electromagnetic means to said first position.