DE2603439A1 - PUNCH HEAD FOR FASTENING NUTS - Google Patents

Description

Dipl.-Ing. H. Sauerland · Dn.-Ing. R. König · Dipl.-Ing. K. Bergen Patent Attorneys · 4ood Düsseldorf 3D · Cecilienallee ve. ■ Telephone 43273s

29 ', January 1976 30 355 B

MULTIFASTENER CORPORATION, 12668 Arnold Avenue, Detroit , Michigan 48239 (V ₀ St.A ₀ )

"Punch head for fastening nuts"

The invention "relates to a punching head for fastening of nuts, in particular punch nuts and rivet nuts, with two telescopic housing parts, one of which is one Stamp and the other a transverse to the stamp axis extending channel for receiving the nuts and one has another channel for the stamp, which is in communication with the first channel, further with holding members for moving the housing parts apart and with a feed for the nuts from the first into the second Channel under the stamp

Such punch heads are known and are generally only designed for processing one type of nuts, either for nuts as bulk material or for those in strip form _o Force-fed punch heads in which the nuts are conveyed into the channel of the punch with a pawl moved to and fro , are generally limited to processing nuts in strip form. The strip is inserted into the stamp channel; the punch then shears off the last nut from the strip. However, problems have arisen with the known positive feed systems. A reliably functioning interruption system had to be in place.

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can be seen to prevent the nut strip from being fed prior to actuation of the ram Avoid jamming or breaking of the feeding system. Furthermore, the nuts must be brought exactly under the punch in order to only partially feed or to prevent the punch head from jamming. Finally, nuts cannot be selected with the known punching heads processed in bulk or in strips.

For example, a punch nut that can be fastened with the punch head described herein is disclosed in U.S. Patent 3,152,628 disclosed. Punch nuts are generally square fasteners with a shoulder on one end and one of these oppositely arranged perforated guide part and punch into a sheet metal ode.r Like. The opening required for its attachment itself. A rivet nut, however, is usually in given a pre-punched sheet metal opening and deformed to the bracket. A suitable rivet nut that with the invention The punch head is described in U.S. Patent 2,750,660. There are also punching and rivet nut systems have been developed in which the nut punches out a sheet metal opening and then to the Bracket and fuse is compressed or riveted.

More recently, punch nuts and rivet nuts have been developed in the form of strips, the nut strip being arranged in the nut channel and the punch shears off the respective end nut from the strip in order to attach it to a sheet metal _{or the like} under the punch channel to attach. The feed mechanism advances the nut strip, one at a time

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Bringing a single nut under the punch for shearing and punching. A punch nut strip system is shown in U.S. Patent 3,711,931. Combined punch and rivet nut strips are also available in which the nuts are connected on a continuous strip by shoulder-forming sections ₀

A punch head that is used in particular for feeding and fastening punch nuts in bulk is described in U.S. Patent 3,089,360. From US Pat. No. 3,108,368 there is a method of fastening of punch nuts known by size. The feed used for this cannot be referred to as a forced feed because the punch nuts are resiliently brought into their punching position. A punching head that works without forced feed for a nut strip is in U.S. Patent 3,810,290 and a positive feed for nut strips is disclosed in U.S. Patent 3,811,171.

A particular problem when feeding punch nuts or rivet nuts in strip form is the adaptation of the usual ones Strip tolerances, including the spacing between the nuts, the nut tolerances and the like., whereby the latter also applies to nuts present as bulk goods «, The dimensional deviations can also add up and cause only partial feeding of nuts and the like as well as breakage or jamming of the punch head. In addition, a forced feed was previously only possible when using nuts in Strip shape possible

The object of the invention is to provide a punching head of the type mentioned, in which the punching or Rivet nuts optionally as bulk goods or in strip

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form can be used, and the more reliable operation compared to known designs the compulsory introduction allows or enables;

This object is achieved in a punching head of the type described in that the feed is a Drive linkage articulated with the first housing part and having a free end, one with the second housing part articulated feed rod with a guide slot directed towards the free end and receiving this when the housing parts are moved apart, a guide device for converting the arcuate movement of the free end around the articulated connection in relation to the second housing part rectilinear movement during a closing movement of the housing parts and an articulated movement with the feed rod Pawl for feeding the fastening elements from the nut channel into the punch channel under the punch has when the feed rod rotates.

A kind of closing movement of the two housing parts, with the housing parts being pushed further into one another, presses the free end of the drive linkage against one side of the slot and rotates the drive linkage to advance the pawl in the nut channel and a nut to bring under the stamp. The driven or feed rod in the guide slot can be advantageous parallel to the linear movement of the free end of the drive linkage controlling the feeding of a nut under the punch have a contact surface that the pawl up to the end of the nut installation cycle in their in the extended position. When there is an opening movement between the housing parts, the feed rod rotates

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in the opposite direction and brings the drive mechanism in operational position.

The feed rod can expediently have a coupling mechanism that prevents damage to the feed rod or the pawl, "This situation can occur when a nut strip is processed after it has been inserted into the punching head," If the nut strip is inserted into the punch channel before actuation of the punch, the feed mechanism tries to introduce a nut into the punch channel and thereby jams _{the feed pawl β.} According to the invention, the feed rod can have two parts connected to one another via the coupling mechanism. These can have intermeshing projections with pitch angles that allow relative movement of the parts of the feed rod in one direction when the nuts are blocked in the nut channel. The parts are held in place by resilient spring washers that press the projections against one another.

Furthermore, the punch head can have a component that forms an inhibition threshold for a certain nut and prevents that a ready-to-use nut that has arrived next to the punch channel is withdrawn into the nut channel «, The reciprocating pawl then engages the second nut, which is spaced from the punch and moves in the direction of the punch, when the pawl moves backwards, the nut resistance holds the next one Nut ready for punching next to the punch channel. In a preferred embodiment of the invention, the The stroke length of the pawl is particularly important in order to bring one nut exactly under the punch and one only partially Prevent nuts from entering the punch channel.

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The stroke of the pawl should be equal or greater than the sum of the gaps between the nuts in the channel, des Distance by which the nut adjacent to the punch is withdrawn until it comes into contact with the nut resistance the smaller diameter of the nut openings and twice the width of the nut edges, measured from the nut opening to the adjacent nut side ο Furthermore, the stroke should be smaller than twice the length of the nuts placed in the channel, measured from opposite nut sides. These conditions ensure a precise arrangement of a nut under the punch.

Furthermore, the punching head can have a stop near the confluence of the nut and punch channel, which allows nuts to be fed into the punch channel only when the punching head is actuated. The stopper can be made in addition to the stamp _e of an elongated, articulated between its ends on the housing stop lever One end of the lever extends at an angle to the longitudinal axis of the reciprocating plunger when the plunger is located above the mouth of the channels, and blocks the nut channel. When the ram is actuated, the stop lever is pushed out of its blocking position. In another embodiment, a pair of resilient pins can be provided on opposite sides of the nut channel adjacent the entry to the punch channel. When the feed pawl is actuated, the nut is pushed through between the stop pins.

A measuring sensor can preferably be provided in the punch head housing to prevent actuation of the punch head if there is no ready-to-use nut.

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The sensor can have a channel-like shaped arm, which in the direction of each in the nut channel next to the nut lying on the punch channel is open and is in contact with this «, the arm scanning the nut is articulated to a switch and closes the switch when the nut is ready for use. Of the The ratchet arm can move into the channel-like shaped probe arm to unhindered nuts under the punch to promote. In another embodiment, the feeler arm is biased against the latch arm.

When a nut has got into the punch channel, it is preferably supported by guide rails which are arranged on opposite sides of the punch channel. The guide rails are held in grooves in the punch channel and are held by a flexible insert so that they protrude into the punch channel. Finally, the punching head can have a device which prevents a fastening element provided for punching from being withdrawn into the nut channel and / or a partial supply of nuts from occurring. The device has egg nen articulated to the - punching head bandaged arm with a finger on which is resiliently pressed into the nut channel. The end portion of the arm has a control surface which faces the nuts entering the punch channel, so that the device is brought out of its locking position by the nuts fed to the punch channel.

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In the following, the invention is explained in detail with reference to the exemplary embodiments shown in the drawing explained. Show it:

FIG _o 1 is a partially sectioned side view of a punch head, which is ready for mounting of a fastening element;

FIG. 2 shows a section in the direction of arrows 2-2 through the object according to FIG. 1;

3 shows a partially sectioned side view of the object according to FIG. 1 after a fastening element has been attached;

Fig. 4 shows a section in the direction of the arrows 4-4 through the article of Figure 1 _o;

FIG. 5 shows a section in the direction of arrows 5-5 through the object according to FIG. 1;

FIG. 6 shows a partially sectioned side view of another embodiment of the object according to FIG. 1;

7 shows a section in the direction of arrows 7-7 through the object according to FIGS. 6;

8 shows a section in the direction of arrows 8-8 through the object according to FIG. 6;

9 shows a schematic representation of a feed pawl to illustrate the pawl path and the dimensional relationships; and

FIG. 10 shows a schematic illustration, similar to FIG. 9, to illustrate the dimensional relationships between the nuts fed in and the nut holding arm.

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The punch head according to the invention is used in particular Feeding and fitting of rivet and punch nuts, which are either in bulk or in strip form. The punch head shown in Figures 1 ″ to 5 conveys and processes a plurality of conventional punch nuts 22. The punch nuts shown are essentially rectangular and have a shoulder 24 formed end as well as a punching guide part and a groove 28 for receiving and fastening the sheet metal after the punching process. A detailed description of pierce nuts is contained in the US patent 3 152 628. The punch head according to the invention can also be used to fasten punch nuts or rivet nuts as disclosed in US Pat. No. 3,711,931 ",

The illustrated version of the punching head for fasteners has two telescopic housing parts, namely a stationary housing part 32 and a relative housing part 34 movable for this purpose. The punching head can be used in combination with a conventional forming tool are so that at the same time a sheet is formed in the desired manner and the punch or rivet nuts on Sheet metal to be attached. The illustrated embodiment then has a connecting plate 36 which is attached to the stationary Housing part with suitable screws 38 or the like. is attached. The component designated by the reference numeral 40 can be a part of a forming die in which the Punch head is attached, or represent a conventional battering ram, which is on the sheet metal or another Component 42 for receiving the fastening elements or punch nuts 22 is moved towards and away from it.

In the embodiment shown, the telescopic housing parts are secured by a bolt or pin

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held together, which extends through the movable housing part 34 and is held in a slot 46, which is arranged in the stationary housing part 32 to allow relative mobility between the housing parts to enable. The housing parts are normally "elongated" with respect to one another, i. apart position, as shown in Fig. 1, under the action of a helical spring 48; one end of the coil spring is in a pocket 50 in the stationary housing part 32 and the opposite End held in a chamber or pocket 52 of the movable housing part 34. It goes without saying that the type of spring or the device for pushing the housing parts apart depends on the specific application, in particular depends on the distance between the housing parts and the spring strength that is desired to to stretch the housing parts. The illustrated embodiment of the punching head also has a separate one Nose 54, which is attached to the movable housing part 34 with a suitable bolt or pin 56.

The sheet metal 42 for receiving the fastening elements punched with the punching head 20 is, as shown, held against the nose 54 by a die part 58. The Matritzenteil 58 supports the sheet 42 during stamping of the fasteners and takes on the punched Wandpfropfen, as will be described further below ₀

The illustrated embodiment of the punching head also has a nut channel 62 for receiving several Nuts and a perpendicular to this punch channel 64, which is in connection with the nut channel stands and a stamp 66 receives the relative to

movable housing part 34 in the stamp channel 64 is movable back and forth. The stamp is in the stationary housing part and in the illustrated embodiment by a pin extending transversely to the punch 68 held. The punch nuts 22 that have got into the nut channel 62 are fed with a feed mechanism 70 brought into the punch channel 64 under the punch 66. A stop lever 72 is provided to prevent that the pierce nuts enter the punch channel 64, except for a downward movement of the Stamp 66, Furthermore, the embodiment shown has a holding arm 74, which prevents the nut channel 62 nuts lying close to the punch channel 64 are withdrawn into the nut channel. A probe is provided to the position of a located next to the punch channel, and thus ready for installation nut to grasp ,, The structure and mode of operation of each Components of the punch head are described below.

The feeding mechanism of the illustrated embodiment has a drive linkage 80, a guide part 94 to Cross guide, a powered or feed linkage 102 and a ratchet arm 112. The drive linkage 80 is articulated to the stationary housing part 32 via a pin 82. In the upper section of the stationary housing part is a slot 84 to allow pivoting of the drive linkage about the Pin 82 to allow, and a stop 86 is provided to prevent the drive linkage rotates clockwise beyond the position shown in FIG. The free end of the drive linkage is is fork-shaped, as shown in FIG. 4, and receives a guide pin 90. The leadership

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pin is in a guide slot 92 in the guide part 94 held as shown in FIG. The guide part thus sets the normally arcuate movement of the free end 88 of the drive rod 80 in a relative to the movable housing part 34 linear Movement that is directed generally transverse to that of the punch 66. The related linear movement of the guide pin 90 can best be from one Recognize the comparison of FIGS. 1 and 3.

In the illustrated embodiment, the guide part 94 is a separate part that can be secured with suitable fasteners, like screws 98, is attached to the stationary housing part 34. The guide pin 90 will introduced into the closed guide part 94 through an opening 100, as can best be seen from FIG.

The driven or feed rod is articulated with connected to the movable housing part 34 via a pivot 104. The driven end of the pushrod 102 has a slot 106 best seen in Figures 3 and 4 and one across extending contact surface 108, which merges into the slot 106 o

The pawl arm 112 is articulated between its ends connected to the downwardly extending end of the pushrod 102 via a pin 114. A The end of the pawl arm has a protruding finger 116 which presses elastically against a nut 22 and is held with a spring 118 in the nut channel 62. The latch finger 116 engages in nut openings, as shown in FIGS. 3 and 5. The swivel

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As can be seen from FIG. 5, the end of the latch arm is fork-shaped and takes the outer or lower one End of the feed rod. One end of the spring 118 is connected to the movable housing part via a pin 124 connected; the opposite end of the spring is between the forked ends of the latch arm a connecting web 126 held, as shown in FIG.

The function of the feed mechanism 70 results on best from a comparison of FIGS. 1 and 3. When the piston or the molding tool 40 moves downwards the nose 54 of the punching head meets that of the die part 58 supported sheet metal 42. The movable housing part 34 is against the stationary housing part 32 pressed, with both housing parts telescopically perform a closing movement relative to one another. During the closing movement, the drive linkage 80 rotates counterclockwise around the hinge pin 82. The resulting arcuate movement of the guide pin 90 is through the guide slot 92 of the Guide part 94 translated into a linear movement relative to the movable housing part 34. The guide pin first engages a push edge 110 of the slot 106 and rotates the feed linkage 102 clockwise about the pivot pin 104, as in FIGS shown. The rotational movement of the feed rod thus causes the ratchet arm 112 to be in the nut channel Advance 62 in the direction of the punch channel 64 in order to bring a nut under the punch 66, As will be described in more detail below, the guide pin 90 finally comes into contact with the abutment surface 108 of the feed rod 102, as shown in Figo, and holds the feed rod and the

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Ratchet arm in the position shown in Fig. 3, while the nut is gripped by the punch 66 and fastened. The contact surface 108 now runs parallel to the Guide slot 92, as shown in Fig. 3, so that the feed rod 102 is not caused to move any further.

After attaching the nut under the punch, the movement of the feed mechanism is reversed. The piston or die 40 is moved upwards (Fig. 1) and rotates the drive linkage clockwise, until the guide pin 90 enters the slot. The pen then lies against the opposite one Side of the slot 106, rotates the pushrod 102 counterclockwise and pulls the pawl arm 112 back to the right. The pawl finger 116 has a control surface 128 that is in contact with the wall of the nut opening and lifts your finger out of the nut opening when the pawl arm 112 is in the position shown in FIG. 1 is withdrawn position in which it is ready for the next cycle.

As mentioned, the stop lever 72 prevents punch nuts 22 at the entry into the punch channel 64, except for a downward movement of the punch 66. The stop lever 72 is articulated with the movable housing part 34, near the punch 66, via a pin 132 connected. In the case of the extended housing position shown in FIG. 1, the upper arm 134 is between a wall of the stationary housing part 32 and the punch 66 enclosed. The lower arm 136 extends at an angle into the punch channel 64 to prevent the entry of punch nuts 22 into the punch channel to prevent. The stamp shows a tax

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surface 138, which extends parallel to the lower arm 136, which is located in the region of the lower end of the punch. A slot or recess 140 for receiving the upper arm of the stop lever is provided in the punch at some distance from the control surface 138, as described in more detail below. In addition, a recess 142 is provided in the upper arm 134 of the soleplate lever to enable the upper arm 134 to rotate freely into the recess 140, _{or the like}

When the punch head is actuated, i.e. when the piston or forming die 40 moves downwards, it hits the control surface 138 of the ram on the lower arm 136 of the stop lever 72 and rotates the stop lever 72 around the pin 132. When attaching nuts, a nut first hits the lower arm 136 and rotates when the ram 66 and the feed mechanism 70 are actuated, the stop lever moves out of its blocking position. When the ram 66 moves downward relative to the movable housing part 34, as shown in FIG. the upper arm 134 of the stop lever is received by the recess 140, as shown in FIG. 3. the Recess 142 allows the stop lever to rotate freely about a control surface 144 “Finally the lower arm of the stop lever is received by a space formed by the nose 54 and the punch 66.

When the housing parts spread under the action of the spring 48, the upper arm 134 strikes the control surface 144 of the punch recess 140 and turns the stop lever 72 counterclockwise until it finally moves into the in Fig. 1 shows the blocking position, the Prevents the upper arm 134 from striking the punch, that a nut enters the punch channel 64 adjacent the lower end of the lower arm 136. This

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This feature is particularly important with a punch head having a positive feed mechanism 70, particularly when using fasteners in the form of strips. When a new strip of fasteners is inserted into the nut channel 62, the strip can extend into the punch channel 64 under the punch 66 unless a positive stop is provided is arranged in the plunger channel, causing a downward movement of the plunger forward movement of the pawl arm 112 in the direction of the plunger channel, wherein the mother strip would, however, then blocked at the opposite wall of the plunger channel _e in such a situation could be the supply -Mechanism damaged in such a way that the punch head needs to be repaired ₀

The holding arm 74 extends substantially parallel to the nut channel 62 and is articulated on the movable housing part via a pin 144. As shown, an arm 146 extends toward the punch channel 64 at an angle relative to a oppositely arranged arm 148. The holding arm is relatively thin and consists of elastic metal. Laterally extending shoulders 150 and 151 are supported against the movable housing part 34, to resiliently push the arm 146 into the nut channel 62 while a retaining finger 16O is biased engages elastically through an opening in the bottom wall of the nut channel 62. In a preferred embodiment of the retaining arm, the finger 160 is shaped to fit into nut openings 120. The retaining arm goes so far that the finger is in a near the

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The nut located in the punch channel 64 engages in order to prevent a nut ready for processing from being withdrawn into the nut channel 62, as will be described in more detail elsewhere. Thus, when a nut strip is used, the retaining arm prevents the strip from being withdrawn into the nut channel. The finger further comprises a control surface 162, which permits that the nuts upon actuation of the feeding mechanism in the nuts channel are inserted ₀ In the event that a mother strip from the punching head must be removed, such as during a repair, the Retaining arm 74 can be withdrawn from the movable housing part, the finger 160 being resiliently withdrawn from the retaining engagement in order to enable the nutstrip to be withdrawn «,

In the preferred embodiment, the nut in the nut channel 64 is supported by guide rails 166 and vertical Guides 168 supported and guided. The guide rails are best seen in Fig. 2. In the embodiment shown, the guide rails horizontal pins or rods 170 lying substantially in the plane of the fastening elements supporting Walls of the nut channel 62 are arranged. Resilient pads 172 press the pins into the Stamp channel as shown in FIG. The pens are

held in substantially circular recesses 174 formed in the opposing walls of the nose 54. The width of the openings of the recesses to the parent channel out is less than the diameter of the pins, and the semi-circular documents 172 push the pins resiliently in the area of the nut channel to respectively hold a nut below the punch, as shown in FIG _o 2 Darge -

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posed. The pins 170 are preferably made of a relatively hard metal and the resilient pads 172 are preferably made of a relatively tough, resilient plastic. A suitable plastic for the pads is a relatively hard polyurethane, such as that sold by J ₀ P. Stephens & Co., Inc. under the trade name "hi-tuff" 75 - D. The respectively ready nut 22 is thus taken up by the guide rails and held by the pins 170 below the punch. Upon contact with the punch, the pins 170 are pressed resiliently into the recesses 174 and allow a nut to pass through the nut channel 64 for installation, which will be explained later.

The vertical guide 168 ensures a trouble-free guidance of the nut by the nut channel and prevents the nuts after passing through the guide rails 166 falls through the channel _o is the vertical guide 168 is cylindrical in the illustrated embodiment, and extends parallel to the movement axis of the punch 66. In known designs of punch heads for rivet and punch nuts, a number of ball bearings were arranged in the wall of the nose 54, which were elastically pressed into the stamp channel by springs. The ability of an elastic base to replace resilient ball bearings without premature wear or premature failure was surprising, since it was not foreseeable, especially not in the case of a punching head for rivet or punch nuts in which hard metal nuts are brought under the punch. The preferred material for the cylindrical base is again a relatively tough, extremely impact-resistant polyurethane such as the above-mentioned polyurethane «,

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• Λ-

In a preferred embodiment, the probe 76 is located in the housing to avoid damage or Preventing pollution and intended for identifying and displaying a ready-to-use nut. As described above, this ensures the supply of all nuts arranged in the nut channel and ensures that a nut is detected each time the punch head is actuated. This is especially important when the punch head, as described above, in combination with a sheet metal deforming tool or the like. used will. In addition, in many applications, the deforming tool has a plurality of punching heads that Fasten nuts at different points on the workpiece. The sensor can in this embodiment can also be electrically coupled to the actuation of the die 66 or forming die, and their actuation stop to ensure the punching of one nut each time the punch is pressed "

The illustrated embodiment of the sensor has a switch. 178, which is fastened to a housing 180 and to the movable housing part 34 with screws 182. The switch has an arm or tongue 184 which is in contact with a switch button 186 to complete the circuit as shown in FIG. The probe further includes an articulated manner to the switch housing 180 connected to sensing arm 188 which has a side in contact with the switch tongue 184 stop, as shown in Fig _s 3 of the feeler arm ends in a channel-shaped portion 192, which is intended, to feel a nut located in the nut channel 62 near the punch channel 64 and ready for installation »

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When a nut comes near the punch channel 64, as shown in Figures 1 and 3, the channel-like section 192 of the probe arm in the Pivoted clockwise about its axis of rotation to touch the switch tongue 184 and the circuit of the Switch 178 to close. If a nut is not yet ready for processing, it rotates Probe arm 188 counterclockwise in the direction of the nut-supporting wall of the nut channel 62 and causes the switch button 186 to exit the housing and open the circuit of the switch. As already mentioned, the circuit can be connected in series with an actuation circuit of the piston or plunger 40 and thereby stop actuation of the punch head when a nut is not yet in the installation position. On the other hand, the switch can be connected to a display device that activates a light or alarm signal, if there is no ready-to-use nut, thereby informing an operator that the punch head Nuts or requires repair.

The funct term of the punch head 20 when inserting a Nut in a sheet then proceed as follows: The nuts are picked up by the nut channel 62 and touch the arm 136 of the stop lever 72. The punch head is brought into the position shown in Fig. 1, wherein the nose 54 the plate 42 to which the nut is to be attached, touches. The die part 58 supports the sheet metal for installing the nut. The piston or die 40 is pressed down in the direction of the sheet metal, thereby closes the two housing parts relative to one another and actuates the feed mechanism 70. Thus the feed rod 102 is rotated clockwise, causing the pawl arm 112 toward the

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Stamp channel 64 "is moved. When the latch arm is moved Moved towards the punch, the pawl finger 116 engages the second nut, which is in some Distance from the stamp channel 64 is located. The finger is pressed onto the nuts by the spring 118. With further Movement of the ratchet arm 112 brings the nut adjacent to the punch channel under the punch The stop lever 72 is turned clockwise by the nut entering the punch channel and enabled thus a mother to enter the stamp channel. The nut is then on the guide rails 166 as shown in FIG. The lower end of the punch then engages the shoulder 24 of the Nut and presses the nut down through the punch channel 64 until it hits the sheet metal 42 and then Fasten the nut in the punched sheet metal opening. As from the patents mentioned at the beginning, in which punch nuts and rivet nuts are disclosed, it emerges that the guide part 26 of the punch nut punches a piece 196 from the sheet metal and the nut is inserted into the punched opening, with the sheet metal in the Groove 28 engages. The punched-out piece 196 falls through the opening 198 into the mattress part 58. Towards the end of the Punching process is the guide pin 90 of the drive linkage in contact with the contact surface 108 of the Feed rod 102. The contact surface 108 then runs parallel to the guide slot 92 in the guide part During installation of the nut, the lower end of the pawl arm is channeled from the End section of the feeler arm added.

After the end of the punch cycle, the spring 48 spreads the telescopic housing parts and rotates the stop lever 72 counterclockwise to the position shown in FIG.

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Set position Lind pulls the pawl arm 112 to the right (Figures 1 and 3) back. The pawl finger 116 has a control surface which lifts the finger out of the nut opening and finally into a position shown in FIG. 1 in which it normally rests on the nut surface of the second nut, which is arranged at a distance from the punch channel In further detail, the punch head has a locking mechanism 202 which is used to relieve the pawl arm during repair or maintenance of the punch head. For this purpose, the bolt has a spring-loaded bolt 204 which is held in a cylindrical opening in the movable housing part 34. The pin 204 can be shifted so that it detects the end of the pawl arm 112 when the finger is held in a nut opening, whereby the ratchet arm 112 is rotated clockwise and the nut or nut strip releases _o The housing parts 32 and 34 may by pulling of the bolt or pin £ 4 must be separated from each other.

The length of the stroke of the back and forth movement of the ratchet arm is of great importance for the operation of the punch head, so that an exact positioning of each nut below the punch is guaranteed and only one The nut partially pushed under the punch, which would lead to breakage and thus to considerable disturbances, is avoided.

As shown in Fig ₀ 9, the latch arm two possible guide surfaces on the edge 210 of the pawl finger 116 which usually detects the opening of a nut, and the edge 212 which can feed a mother if a particularly large gap between the Nuts or the last nut in the channel

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appears. A feed with the edge 212 is also possible with a nut strip when the nuts are on the bracket are arranged at a distance from one another.

It has been found that there is a relationship between the distance traveled by the pawl arm, as shown in FIG Thread, and the edge width of the nut results in »This relationship is summarized in the following equation: Distance or stroke = X + B + D _M + 2N: where" X "equals the length of the gap between the nuts or the distance between the nuts the drift is; "B" is the slip, which results mainly from the play between the threaded hole and the support arm; "D _M " is the inside diameter of the threaded hole; 2 N is twice the edge width of the nut. The relationship between these dimensions is shown in FIGS

Four additional conditions should also be considered in order to satisfy the path equation and ensure accurate positioning of the feeder, namely: 1) The path must be less than twice the nut length minus once the edge width "N" of a nut. 2) The path must be greater than the gap "X ^R between the nuts when a strip is fed. 3) The effective length ^M Z ^{M of} the pawl must be equal to or less than the length of the gap" X "in the strip. 4 ) The effective length ¹¹ Z "or the width" W "of the feed pawl must be greater than the inner diameter" D _M "of the thread. If the effective length "Z" of the feed pawl were less r than the diameter "D _M ^{n" of} the threaded hole, the control surfaces of the pawl would engage the threaded hole and advance the strip too far by the length "Ny".

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A typical commercially available punch nut has a cutting length of approx. 1.27 cm, the gap "X" being approx. 0.71A- cm, the slip ^U B "0.112 cm, the diameter" ^ · ^{1 of} the threaded hole 0.673 cm and the edge width "N" of the nut is approx. 0.298 cm. Under these conditions, the stroke is approximately 2.08 cm according to the equation given above.

It will be understood that the equation given above is developed primarily for the advancement of nut strips where the gap between the nuts is of particular importance. However, the equation is alike applicable to the supply of nuts present as bulk goods, with the difference that the gap "X" is usually 0.

The embodiment of the punching head shown in FIGS. 6 and 7 has certain modifications compared to the embodiment shown in FIGS. These changes mainly affect the feed mechanism and the probe. As shown in Figures 6 and 7, the punching head 220, a stationary housing 232 which is substantially identical to the above-described housing part 32. The stationary housing part comprises a punch 226 that is slightly modified as described below _o The movable Housing part 234 has been lengthened, whereby the length of the punch path "a ^M" up to the contact with the nut has been increased. The spring 24β normally pushes the two housing parts apart, around the punch 226 above the opening of the nut channel 262 into the punch channel 264 to position.

The feed mechanism is in this embodiment designed similarly and has a drive linkage 280

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that is articulated to the stationary housing part 232 is connected and has a guide pin 290 at the free end, which is arranged in a guide component 294 and is guided that the arcuate movement of the guide pin 290 in a relative to the movable housing part 234 implements linear motion. The ■ feed linkage consists of two parts 302, 303 which are connected to one another via a coupling 400. The components of the punching head shown in Fig. 6 are in the same way as the components of the punching head according to 1 to 5 denoted or numbered. In comparison, the clutch is a new component. The feed rod is articulated with the movable one

Housing part connected by a journal 304 which extends through the coupling, as in FIG. 7 shown.

The coupling has a shouldered outer hub 402 and one threaded therein inner hub 404 that holds the assembly together. A plurality of spring washer-like spring washers (Belleville-type thrust washers) are between the shouldered end of the inner hub and the upper part 302 of the pushrod. The spring washers normally hold parts 302 and 303 together as a unit so that the feed mechanism 270 is normally essentially as described above is working. However, it should be pointed out that the contact surface of the upper part 302 is somewhat different here is designed to sdJe the greater distance between to adapt to the guide pin 290 and the articulated connection on the journal 304 ”, This resulted from the enlargement of the stamp path "a".

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During operation, a closing movement of the housing parts 232 and 234, the drive linkage 280 pivoted counterclockwise, rotating the feed linkage clockwise and advancing the pawl arm 312 toward the punch channel 264. In the embodiment in the figures 1 to 5 shown stop lever 72 can be omitted in this embodiment, because the coupling is such makes redundant. If individual nuts or a nut strip 222 gets into the punch head, can the nuts in this embodiment are placed directly into the punch channel 264, with the first nut is placed under the punch 226. When the feed mechanism 270 is actuated, the pawl finger grips 316 into the second mother as described above. The pawl arm 312 cannot, however, point towards the punch channel 264 because there is already a nut in the punch channel. In this situation it pans the upper part 302 of the driven member clockwise about the pivot axis of the pin 304 and the lower part 303 remains. This is made possible by the coupling 400.

After the nut located in the punch channel 264 has been attached, the spring 248 presses the two housing parts apart, with the pushrod 302 rotated counterclockwise and the end of the pawl arm 312 pressed against the housing from section 40 6 and the feed mechanism in its operational position in Fig. 6 is returned. As shown in Fig. 7, the parts 302 and 303 are circular with each other cooperating projections with a control surface 401, the relative movement of the part 302 in a counterclockwise direction relative to part 303 prevented. When loading

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movement of the pawl arm 312 against the housing section 406, the parts 302 and 303 are returned to their position shown in FIG.

The holding device shown in Fig. 8 can "in the 6 or the stop lever shown in FIGS. 1 to 3 can be used 72 replace. It goes without saying that the stop lever shown in FIGS. 1 to 3 works inevitably 72 is preferable for a positive feed mechanism because the nuts in use of the stop lever 72 can only be supplied when the plunger 66 is actuated.

As shown in Fig. 8, the nose 254 supporting guide rails 366 and a vertical guide 368 to _0, the guide rails 366 könim identical to the guide rails 166 of the embodiment and represented in the figures 1 to 5 the vertical guide 368 may be similar to the vertical guide 166 The embodiment shown in Figures 1 to 5, with the difference that the guide 368 extended beyond the mouth of the nut and punch channel are pressed into the area of the nut channel "As shown, the pins 410 extend perpendicular to the nut channel and essentially parallel to the axis of the reciprocating punch 226" The pins are in semicircular grooves next to the mouth between the nut channel Channel 262 and the stamp channel 264 arranged. The pins 410 are preferably made of hard metal and the pads 412 can be flexible polyurethane, as has been described in connection with the guide rails 166. As shown, the distance is between

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-af-

the pins 410 are normally slightly less than the width of the nuts 22 so that the entry of nuts into the punch channel 264 is blocked. Upon actuation of the feeding mechanism 270 in Fig. 6, the nuts 22 push the pins 410 elastically in the formed in the nose 254 grooves against the compliant documents 412, so that a nut into the plunger channel is introduced 264 ₀ The nut is on Guide rails 366 held until they engage the punch 66 and are secured.

This embodiment of the punch head also has a modified sensor 276 which has a switch 378 has a switch button 386 which is connected to the circuit for the stamp actuation or a display device in Can be connected. The shift lever or tongue 384 in this embodiment has a roller 387, which unrolls on the latch arm on the side opposite finger 316,

The Fig * 6 shows none in the vicinity of the stamp channel located mother. The ratchet arm therefore rests on the wall of the nut channel 262 that carries the nut and the button 386 of the switch 378 is extended so that the circuit of the switch is opened. As soon as a nut comes close to the punch channel, the pawl arm 312 is pivoted clockwise, whereby he grasps the roller 387, pushes the switch tongue 384 in the direction of the switch 378 and this closes. The roller engages the thicker portion of the pawl arm 312 when the finger 316 is in a nut opening is located? the pawl arm 312 is advanced to advance a nut into the punch channel 264,

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while the probe circuit remains closed.

In the embodiments in Figures 1 to 5 and The switch used in Figures 6 and 7 can be a commercially available conventional normally open switch Microswitches of the type shown in Figures 1 and 6 as well as other types are commercially available.

The mode of operation of the embodiment of the punching head shown in FIG. 6 is therefore the same as that of the embodiment described with reference to FIGS. The unmarked components of the punching head according to FIG. 6 can be identical to the components of the embodiment according to FIG. ₀ 1.

It will be understood that various modifications have been made to the illustrated embodiments of the punch head can be, for example, the movable housing * part 34 according to FIGS. 1 and 3 can be extended, as shown in FIG. 6, by the path of the punch 66 in the embodiment shown in FIGS. 1 to 5, the slot 106 and the contact surface 108 of the Feed linkages 102 can also be varied to control the reciprocating motion of the pawl arm 112. The spring 248 can be configured differently depending on the requirements of a punch head. To the For example, two or more springs can be used or some other suitable pressure device can also be used be used. Furthermore, various components of the illustrated embodiments of the punch head for different uses of the punch head among each other be replaced.

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Claims (1)

MOLTIFASTEiNER CORPORATION, 12668 Arnold Avenue, Detroit , Michigan 48239 (V.St.A.) Claims; 1.) Punch head for fastening nuts, especially punching and rivet nuts, with two telescopically movable housing parts, one of which is a punch and the other a channel extending transversely to the punch axis for receiving the nuts and another Has channel for the stamp, which is in communication with the first channel, further with holding members for holding apart the housing parts and with a feed for the nuts from the first into the second channel below the stamp, characterized in that the feed for supplying the Nuts a drive rod (80, 280) hinged to the first housing part (32, 232) with a free one End, a with the second housing part (34, 234) articulated feed rods (102, 302) with a for directed towards the free end and receiving this when the housing parts (32, 34; 232, 234) are moved apart Guide slot (92), a guide device for converting the arcuate movement of the free end about the articulated connection (pin 82) in relation to FIG the second housing part (34) rectilinear movement during a closing movement of the housing parts (32, 34) and a pawl articulated to the feed rod (102, 302) for feeding the nuts (22, 222) out of the nut channel (62) in the punch channel (64) under the punch (66) when the feed rod (102) rotates. 609849/0240 2ο punching head according to claim 1, characterized that the free end of the drive linkage (80, 280) has a transversely extending Has a pin (90, 290) for engaging the guide slot (92) » 3. punching head according to claim 1, characterized in that the pawl consists of a elongated ratchet arm (112, 312) "exists between its ends on the driven or feed linkage (102, 302) is articulated and near one of its ends a transversely extending shoulder for feeding of nuts (22, 222) in the second channel (64, 264) and a shoulder on those in the first channel Has nuts pressing spring (118). 4. punching head according to claim 1, characterized in that the guide slot (92) of the feed linkage (102, 302) has a control surface, one side of the slot (92) and one Contact surface (.108) includes which the free end of the drive rod (80, 280) receives when the housing parts are in the closed position. 5. punching head according to one or more of claims 1 to 4, characterized by a stop (72) for the nuts (22, 222) and a ratchet arm (112, 312) with one on the nuts {22, 222) in Nut channel (62, 262) facing shoulder whose path is equal to or greater than the sum of the gaps (X) between the nuts (22, 222) in the channel, the distance by which the nut (22) adjacent to the punch (66, 226) returned to contact with a holding device 609849/0240 -y - can be drawn, the smaller diameter (D ™) of the Nut openings (120) and twice the edge width (N) the nuts (22), and is less than twice the length of the nuts (22) located in the channel. 6. punching head according to claim 5, characterized that the shoulder of the pawl (112) has an arcuate edge (212) leading to the Stamp (66, 226) indicates. 7 · punching head according to one or more of claims 1 to 6, characterized in that the at the free end of the drive rod (80, 280) arranged pin (90, 290) slidably held in a slot (92) of the movable housing part (34, 234) is. 8. punch head according to one or more of claims 1 to 7, characterized in that the pawl (112, 312) in the nut channel (62, 262) is arranged, wherein one end of the pawl (112, 312) is resiliently biased and the other end the Nuts (22, 222) detected. 9. punch head according to one or more of claims 1 to 8, characterized in that the feed rod two each with the movable Housing part (234) hinged parts (302, 303) and a coupling (400) between them Has parts (302, 303). 10. punching head according to one or more of claims 1 to 9, characterized in that 109849/0 w 2603Λ39 • w that the parts (302, 303) have projections lying on top of one another with cooperating inclined surfaces and are resiliently pressed against one another by the coupling (400). 11. Punch head according to one or more of claims 1 to 10, characterized in that the drive linkage (80, 280) and the feed linkage (102, 302) are designed as pivot levers ₀ 12. Punch head according to one or more of claims 9 to 11, characterized in that the coupling (400) has several spring washers, which are pressed together against the second part of the lever and normally a relative movement between prevent the parts of the lever while allowing relative movement with a force sufficient to to overcome the contact between the panes «, 13. Punch head according to one or more of claims 1 to 12, characterized in that the stop (72) consists of an elongated arm (136) which is articulated between its ends on the housing is mounted near the punch (66) with one end of the arm (136) extending at an angle into the path of the reciprocating punch (66) extends when the punch (66) extends over the mouth of the channels (62, 64) is to block the nut channel (62) at its mouth in the punch channel (64), while the second End of the arm (136) with the punch (66) is in contact that the punch (66) has a beveled im control surface substantially parallel to the arm (136) (138) and one above the control surface (138) 609849/0240 arranged recess (140), wherein the control surface (138) and the recess (140) of the stamp with each end of the stop (72) cooperate, and that the recess (14O) has a control surface (144) for one end of the stop (72) has " 14. punching head according to claim 13, characterized in that both arms (134, 136) of the stop (72) from the hinge connection designed as a pin (132) extend at an angle, and that an arm (134) has a groove or recess (142) opposite the punch (66). 15. punching head according to claim 13 or 14, characterized characterized in that one arm (136) of the stop (72) is wider than the other arm (134), and that a slot is formed in the channel (64) for the arm (136). 16. Punch head according to one or more of claims 13 to 15, characterized in that the two arms (134, 136) extend at an angle to one another and the second leg has a greater width than the first leg, and that the housing has a in the wall of the punch channel (64) formed recess which is arranged opposite the punch is and for receiving the holding lever next to the stamp serves «, 17. Punch head according to one or more of claims 13 to 16, characterized in that the groove or recess (142) of the arm (134) of the Opposite punch recess (14O) and the 609849/02 The edge delimiting the punch recess takes up during the downward movement of the punch, 18. Punch head according to one or more of claims 1 to 17, characterized by a retainer which prevents one in the first or nut channel (62, 262) from being near the punch channel (64, 264) arranged nut ready for installation from the punching position into the nut channel (62, 262) is withdrawn, and one arm (74, 274) pivoted on the housing with a flexible arm in the Nut channel (62, 262) near the punch channel (64, 264) engaging retaining finger (16O) with one of the channel mouth facing control surface (162) has » 19. punching head according to claim 18, characterized in that the arm (74, 274) extends substantially parallel to the nut channel (62, 262) and close to this with a transversely extending Hinge pin (144) is pivotally connected to the housing «, 20. Punch head according to claim 18 or 19, characterized in that the fastening elements supporting wall of the nut channel (62, 262) has an opening through which the retaining finger (16O) extends into the nut channel " 21. Punch head according to one or more of claims 18 to 20, characterized in that the arm (74, 274) is articulated between its ends is mounted on the housing and the Hai te finger (160) having Arm (146) as well as the arm (148) opposite this with respect to the joint yieldable against the 609849/0240 Housing are pressed so that the retaining finger (160) is pressed resiliently into the nut channel. 22. Punch head according to one or more of claims 18 to 21, characterized in that the ends of the arm (74, 274) from the hinge pin (144) from run at an angle to each other. 23. Punch head according to one or more of claims 18 to 22, characterized by an opening in the punch head for receiving the central section of the arm (74, 274). 24. Punch head according to one or more of claims 1 to 23, characterized by a pair of parallel guide rails (166, 366) which are in Stamp channel (64) are arranged substantially perpendicular to the axis of the reciprocating stamp (66) and which are essentially aligned with the wall of the nut channel (62) carrying the nuts (22), wherein the distance between the rails (166, 366) is somewhat smaller than the width of the nuts (22) and the rails (166, 366) are resiliently supported «, 25. Punching head according to claim 24, characterized that the rails (166, 366) are cylindrical metal pins (170) which are in elastic Documents (172) are embedded. 26. Punch head according to claim 24 or 25, characterized characterized in that the side walls of the punch channel (64) opposite recesses (174) for the rails (166, 366) which 609849/0240 is essentially perpendicular to the axis of the back and forth extending stamp, and that the rails are arranged in the recesses, the resilient Pads are placed between the walls and the rails o 27ο Punching head according to one or more of Claims 1 to 26, characterized in that a leading, flexible guide (168) or base (412) in the punch channel (64, 264) parallel to the axis of the reciprocating punch ( 66, 226) is arranged, which supports the alignment of a nut when it is pushed through the punch channel _{or the like} • r 28. Punch head according to claim 27, characterized in that the guide or base (168, 412) is an elongated, cylindrical insert _o 29. Punch head according to one or more of claims 1 to 28, characterized by a Sensor (76, 276) for a nut (22, 222) that is ready for use in the nut channel (62, 262) with a button that detects the presence or absence of a mother next to the stamp channel and the actuation of the punch if there is no ready-to-use nut available. 30. Punch head according to claim 29, characterized in that the sensor has a connected to the actuation circuit of the ram (66, 226) electrical switch (178, 378) has that the button normally the circuit for actuation 609849/0240 -Vt- of the punch keeps closed if there is a ready-to-use nut in the nut channel next to the punch channel is located, and that the button opens the circuit for actuating the stamp and the actuation of the stamp prevented if there is no ready-to-use nut next to the punch channel. 31. Punching head according to claim 29 or 30, characterized in that the button consists of a flexible probe arm or tongue (188, 384) extending essentially parallel to the nut channel (62) for grasping a nut (22) located next to the punch channel (64). 32ο punching head according to one or more of claims 29 to 31, characterized in that the sensor (76, 276) within the housing in Nut channel (62, 262) is arranged. 33t punching head according to one or more of claims 29 to 32, characterized in that that the probe arm (188) is attached to the housing at the end opposite the probe end in an articulated manner. 34. punching head according to one or more of claims 29 to 33, characterized in that the feeler arm (188) has a section shaped like a channel (192) that extends in the direction of the nut channel (62) held nuts (22) opens and detects them, and that the pawl arm (112) in the channel-like shaped, downwardly open section (192) is movable. 35ο punching head according to one or more of claims 29 to 34, characterized in that 609849/0240 that the feeler arm (188) is in contact with the free end of the pawl arm (312) when the pawl arm is held by a nut located in the nut channel at a distance from the nut channel _o 36. punching head according to claim 35, characterized in that the probe arm (188) has a Roller (387) carries, which touches the ratchet arm (312) in the normal state. 37. punching head according to one or more of claims 1 to 36, characterized by a holding device consisting of two cylindrical pins (410) attached to opposite sides of the Nut channel (62) at its mouth in the punch channel (64) substantially perpendicular to the nut channel are arranged with the distance between the pins is slightly smaller than the width measured across the Nuts channel, the nuts. 38ο Punching head according to claim 37, characterized in that the pins (410) are made of metal and are held in grooves (368) in the opposite side walls of the nut channel with the interposition of flexible supports, _o 39. punching head according to claim 38, characterized in that the documents are semicircular Have cross-section and are made of flexible plastic. Punching head according to one or more of Claims 37 to 39, characterized in that 609849/0240 -ή- that the opening of the grooves (368) towards the channel is narrower than the diameter of the pins (410), and that the Pins (410) protrude into the nut channel (62). 41. Punching head according to one or more of claims 37 "to 40, characterized in that the guides or pads are made of polyurethane" ₀ 609849/0240