Hand riveting tool for blind rivets

Abstract

Hand riveting device (1) for blind rivets (2), comprising a nozzle (4) which can be attached to the component to be riveted and which has a receiving channel (10) for the rivet mandrel (16), and an actuator (5) which applies tensile force to the rivet mandrel (16) until it breaks off, characterized in that the rivet mandrel break-off (17) in the position released by the actuator (9) in the receiving channel (10) is fixed against falling out by a holding magnet (18) arranged in the area of ​​the receiving channel (10) and can be displaced by the subsequently inserted rivet mandrel (16) against the magnetic holding force in the direction of the outlet end of the receiving channel (10).

Description

[0001] The invention relates to a hand riveting device for blind rivets, comprising a nozzle which can be attached to the component to be riveted and which has a receiving channel for the rivet mandrel, and an actuator which applies tensile force to the rivet mandrel until it breaks off, according to the preamble of claim 1.

[0002] To prevent the rivet mandrel fragment from falling out of the mouthpiece opening under the influence of gravity when the mandrel fragment is released from the clamping jaws of the actuator after the setting process and the riveting tool is lifted from the component, the riveting tools known, for example, from DE 24 41 707, DE 10 2010 039 661 A1 or DE 10 2011 001 198 A1 are equipped with a relatively complex and mechanically vulnerable holding or ejection mechanism that pushes the rivet mandrel fragment laterally into the open air or into a collection container connected to the outlet end of the receiving channel.

[0003] Document DE 10 2010 039 670 A1 discloses a riveting device comprising a housing, a holder for a rivet to be set arranged in the housing, a pulling device for engaging a rivet mandrel of the rivet arranged in the holder, a drive for the pulling device, a receiving space for at least one broken-off mandrel formed in the housing behind the rivet holder and extending from the holder, and at least one magnet associated with the receiving space for the broken-off mandrel. The magnets of the riveting device from document DE 10 2010 039 670 A1 serve to pull the broken-off mandrel out of the holder as soon as it moves slightly from the rear end of the holder into the influence of the two magnets, and to pull it completely into the space between the two magnets until its front end rests against the stop.

[0004] Document DE 1 217 175 A discloses a pneumatic-hydraulic hand tool for setting blind rivets, comprising a pneumatic cylinder in which a pneumatic piston with a piston rod, which is guided sealingly in the subsequent hydraulic chamber, slides, and a working cylinder arranged thereon, the working piston of which carries the chuck mechanism for gripping the mandrel and which is connected to the hydraulic chamber by a bore opening below the working piston, wherein the high working pressure is obtained by the pneumatic-hydraulic pressure intensification, for whose control a compressed air valve operated by a hand lever is provided, and wherein furthermore a return spring is arranged between the working piston and the cylinder end, wherein only a short connecting bore between the working cylinder and the hydraulic chamber is provided for the sole purpose of returning to the initial position by the spring.wherein the piston shaft of the pneumatic piston is smaller in diameter than the hydraulic chamber, the pneumatic cylinder has a suction bore to the atmosphere on the shaft side, and a short connecting bore connects the other end of the pneumatic cylinder to the outlet side of the compressed air valve arranged on the pneumatic cylinder. The blind riveting tool from document DE 1 217 175 A essentially consists of a single, elongated, tubular housing body in which the pneumatic system, the hydraulic system, and the chuck with the working piston are housed. The working cylinder for the chuck and its actuating device are arranged almost perpendicular to the normal, elongated shape. The chuck consists of a sleeve part, at the lower end of which a magnetic nozzle with an axial bore can be screwed concentrically into the chuck housing.

[0005] The object of the invention is to design a hand riveting device of the type mentioned above in such a way that the rivet mandrel breakages are retained inside the device in a structurally simple and reliable manner.

[0006] This problem is solved according to the invention by the hand riveting device characterized in claim 1. Advantageous embodiments of the invention are described in dependent claims 2 to 5.

[0007] According to the invention, the rivet mandrel break-off is secured against falling out of the receiving channel by a structurally very simple holding magnet, taking advantage of its magnetizable material properties. This secures the mandrel without clamping force after the clamping jaws of the actuator have been released. During the subsequent setting process, the mandrel, which is then inserted into the receiving channel on the inlet side, is automatically and easily transported past the holding magnet in the direction of insertion. This has the further advantage that the magnetic fixation functions reliably over long periods of time, whereas mechanical fixing devices are comparatively prone to failure, not least due to the abrasion of the rivet mandrels, which usually consist of a galvanized steel pin.

[0008] Preferably, the holding magnet is arranged in the mouthpiece of the riveting tool, i.e., in the insertion direction of the rivet mandrel before the clamping jaws, so that conventional riveting tools can be converted to the design according to the invention by simply removing the existing mouthpiece and replacing it with one with an integrated holding magnet.

[0009] As is still preferred, the rivet mandrel fragments are not ejected into the open air, but are collected in a collection container arranged on the outlet side of the intake channel, and for reasons of easier handling of the riveting device, the actuator is electrically powered, namely battery-operated.

[0010] In a particularly preferred embodiment of the invention, in conjunction with the holding magnet, a very simple, contactless control of the setting process is achieved by a sensor arrangement that detects the magnetic field changes of the holding magnet and responds when a rivet mandrel is inserted into the receiving channel or a mandrel fragment is ejected to the collection container.

[0011] The invention will now be described in more detail with reference to an exemplary embodiment in conjunction with the drawings. These show, in a highly schematic representation: Fig. 1 a hand riveting device designed according to the invention in the setting position after the insertion of a rivet mandrel; Fig. 2 the in Fig. 1 Hand riveting tool shown in the upper stroke end position of the actuator after the rivet mandrel has been detached; and Fig. 3. the riveting tool according to the Fig. 1 and Fig. 2 in the state removed from the rivet point with the rivet break fixed in the receiving channel.

[0012] The hand riveting tool 1 shown in the figures is used for setting blind rivets 2 and comprises as its main components a nozzle 4 fixed in a housing 3 and a battery-operated actuator 5 including a drive 6 for a slidably guided element in the housing 3, between a lower ( Fig. 1 and Fig. 3) and an upper end position ( Fig. 2) a lifting-movable driven tie rod 7, which is conically tapered at its lower end section and interacts with the correspondingly tapered outer surfaces 8 of a clamping jaw set 9.

[0013] The riveting device 1 is permeated by a rivet mandrel receiving channel 10 extending continuously from the nozzle 4 over the drawbar 7 and the drive 6, which leads into a collection container 11 on the top of the riveting device 1.

[0014] Inside the drawbar 7, a pressure piece 12 is guided axially for movement, which is pressed against the clamping jaws 9 by a preload spring 13 via frustoconical contact surfaces 14. Likewise, the mouthpiece 4 and the clamping jaws 9 are provided with corresponding conical surfaces 15.

[0015] During the downward stroke of the drawbar 7, the clamping jaws 9 come into contact with the nozzle 4 in the area of ​​the conical surfaces 15, while the drawbar 7 continues to move to its bottom dead center position, so that the clamping jaws 9 with their conical outer surfaces 8 slide along the drawbar 7 in the direction of expansion of the drawbar's inner surfaces and, under the action of the preload spring 13, the pressure piece 12 and the inclined contact surface pairs 14, 15 between the pressure piece 12 and the clamping jaws 9 on the one hand and between the clamping jaws 9 and the nozzle 4 on the other, are retracted laterally out of the receiving channel 10. This corresponds to the normal rest state of the riveting tool 1, in which it is moved to a riveting point and pushed onto the mandrel 16 of a pre-installed blind rivet 2 with the receiving channel 10 ( Fig. 1).

[0016] Subsequently, the tie rod 7 is abruptly pulled into the upper stroke end position by actuating the electric drive 6. During this process, the clamping jaws 9 are lifted from the assembly at the conical surfaces 15 of the nozzle 4 and, supported by the axial pressure of the pressure piece 12, are pressed so firmly against the rivet mandrel 16 from the sides of the tie rod end section, which is tapered to conform to the surface of its inclined outer surfaces 8, that the mandrel is coupled to the tie rod 7 in a movement-resistant manner and, during the further upward stroke of the tie rod 7, is cut at the predetermined breaking point of the blind rivet 2, whereupon the rivet connection is completed. Fig. 2) Immediately after reaching the top dead center position, the tie rod 7 is retracted into the rest position, thereby releasing the rivet mandrel fragment 17 remaining in the receiving channel 10 from the clamping jaws 9.

[0017] The riveting device 1 is completed by a permanent magnet 18 integrated into the nozzle 4, which reliably fixes the break-off 17 of the magnetizable rivet mandrels 16, usually consisting of galvanized steel pins, in the receiving channel 10 in the retracted position of the clamping jaws 9, so that the riveting device can be lifted from the riveting point after the setting process ( Fig. 3), without the rivet break 17 escaping uncontrollably into the open air via the mouthpiece 4.

[0018] The rivet mandrel fragment 17 remains fixed in the receiving channel 10 until the next setting operation and is pushed by the then inserted rivet mandrel 16 against the holding force of the magnet 18 past the clamping jaws 9 towards the collecting container 11, thereby also pushing along any further mandrel fragments 17.1, 17.2... that may have remained in the receiving channel 10 from previous setting operations ( Fig.1) In general, however, the rivet mandrel fragment 17 is already ejected into the collection container 11 under the impact of the subsequently severed rivet mandrel 16.

[0019] Since the holding magnet 18 – unlike a spring-loaded locking element – ​​has no edges protruding into the receiving channel 10, the described fall-back protection of the mandrel break-off 17 operates largely without abrasion or wear. Furthermore, the placement of the holding magnet 18 in the area of ​​the receiving channel 10 allows for simple monitoring of the setting process by means of a sensor arrangement (not shown) that responds to changes in the magnetic field when a rivet mandrel 16 is inserted into the receiving channel 10 or a mandrel break-off 17 is ejected to the collection container 11.

Claims

[1] Hand riveting tool (1) for blind rivets (2), with a nozzle (4) which can be attached to the component to be riveted and which has a receiving channel (10) for the rivet mandrel (16) and an actuator (5) which applies tensile force to the rivet mandrel (16) until it breaks off, characterized by , that the rivet mandrel break (17) in the position released by the actuator (9) in the receiving channel (10) is fixed against falling out by a holding magnet (18) arranged in the area of ​​the receiving channel (10) and can be displaced by the subsequently inserted rivet mandrel (16) against the magnetic holding force in the direction of the outlet end of the receiving channel (10). [2] Hand riveting device (1) according to claim 1, characterized by , that the holding magnet (18) is a permanent magnet arranged in the mouthpiece (4). [3] Hand riveting device (1) according to claim 1 or 2, characterized by , that a collection container (11) for the ejected rivet mandrel fragments (17) is provided on the outlet side of the intake channel (10). [4] Hand riveting device (1) according to any one of the preceding claims, characterized by , that the actuator (5) is electrically driven. [5] Hand riveting device (1) according to any one of the preceding claims, characterized by a sensor arrangement that responds to changes in the magnetic field of the holding magnet (18).

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