EP0336136B1 - Screw driver bit - Google Patents

Screw driver bit Download PDF

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Publication number
EP0336136B1
EP0336136B1 EP89104230A EP89104230A EP0336136B1 EP 0336136 B1 EP0336136 B1 EP 0336136B1 EP 89104230 A EP89104230 A EP 89104230A EP 89104230 A EP89104230 A EP 89104230A EP 0336136 B1 EP0336136 B1 EP 0336136B1
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EP
European Patent Office
Prior art keywords
section
intermediate section
length
screwdriver bit
screwdriver
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP89104230A
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German (de)
French (fr)
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EP0336136B2 (en
EP0336136A1 (en
Inventor
Karl Lieser
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Wera Werk Hermann Werner GmbH and Co KG
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Wera Werk Hermann Werner GmbH and Co KG
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Application filed by Wera Werk Hermann Werner GmbH and Co KG filed Critical Wera Werk Hermann Werner GmbH and Co KG
Priority to AT89104230T priority Critical patent/ATE75982T1/en
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Publication of EP0336136B1 publication Critical patent/EP0336136B1/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B23/00—Details of, or accessories for, spanners, wrenches, screwdrivers
    • B25B23/14—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers
    • B25B23/142—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B15/00—Screwdrivers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B15/00—Screwdrivers
    • B25B15/001—Screwdrivers characterised by material or shape of the tool bit
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B23/00—Details of, or accessories for, spanners, wrenches, screwdrivers
    • B25B23/14—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers

Definitions

  • the invention relates to a screwdriver insert according to the preamble of claim 1 (see 2.B EP-A-0221279)
  • a twistable zone serves as a predetermined breaking point.
  • the intermediate section breaks when a target torque is reached.
  • These screwdriver bits should not be able to transmit excessive torque peaks when used in machine screw chucks.
  • the insert is a single-use item for tightening screws. It can only be used to a limited extent.
  • the object of the invention is based on the object of designing a generic screwdriver insert in a technically simple manner so that torque peaks acting on the screwdriver insert do not lead to any deformation of the screwdriver tip section, the service life is increased and working with machine screwdrivers is considerably facilitated.
  • a generic screwdriver insert of increased utility value is specified. If higher torque peaks become effective on the screwdriver insert, for example caused by abruptly occurring drive force peaks or by different properties of the material receiving the screw, the intermediate section between the drive end section and the output end section allows an elastic twist / torsion.
  • the intermediate section is an elastically flexible element with a corresponding resilience after the load peak has been overcome. It can withstand greater moments, even with repeated loading. It takes up deformation work and partially stores it in the form of potential energy and returns it when the load is released.
  • the intermediate section acts as a damper so that torque peaks are not directly proportional to the screwdriver tip section. This is reflected in the particularly long service life of the screwdriver insert and the screw.
  • the intermediate section twists.
  • the length and cross section of the intermediate section can be designed in such a way that any energy peaks are always absorbed under load. It is advantageous if the ratio (with normal steel as material for DIN-standardized use) of diameter to length of the intermediate section is in the range between 0.5 and 0.2 or the length of intermediate section 10 corresponds approximately to 3 times the diameter.
  • a further possibility to vary the torsional moment of resistance of the intermediate section is to provide an axial cavity in the intermediate section, which starts from the polygonal section.
  • the axial cavity can be selected to have a different size and a different length to change / adapt the torsional resistance moment of the intermediate section. This makes it possible, for example, to produce screwdriver bits of identical design with different intermediate sections, with regard to its torsional resistance.
  • the intermediate section is preferably a round section stepped in relation to the polygonal section. Screwdriver bits for the transmission of low torques require a correspondingly smaller intermediate section.
  • the number 1 denotes a screwdriver bit in DIN standard (size 2).
  • a Phillips screw 2 illustrated in FIG. 1 can be rotated with this.
  • the latter is composed of a screw shaft 4 having a thread 3 and a countersunk head 5 which contains the cross recess 6.
  • the screwdriver tip 7 is designed in accordance with the cross recess 6 and the associated DIN standard.
  • This has four driving ribs 8 arranged in the same circumferential distribution and thus forms the output end region 9 (screwdriver tip section).
  • This is followed by an intermediate section 10 which is circular in cross section and which has the aforementioned screwdriver tip section 9 and the drive send range 11 connects to each other.
  • the length of the polygonal section 11 corresponds approximately to that of the intermediate section 10.
  • Steel with resilient properties for example chromium-nickel steel, is used to produce the screwdriver insert. It is made by cold forming.
  • the force-transmitting depth of penetration into the screw is generally only about a maximum of half of the section ts From and is also DIN-standardized for the test torques.
  • the elastic ring 16, arranged in an inner groove 15 of the machine chuck 13 bears and thereby pulls the screwdriver bit 1 into the machine chuck 13 until the striking surface 17 at the bottom of the machine chuck 13 is present.
  • This holder can compensate for considerable tolerances due to the pulling-in torque, which in turn accommodates the production of the insert 1 as a whole by means of the cold deformation (which is never so absolutely precise).
  • the total length of the screwdriver bit 1 shown is 25 mm in accordance with the DIN standard.
  • the one minus the polygonal section is about 17 mm.
  • the intermediate section 10 (including section S) and output end section thus take up approximately 70% of the total length of the insert 1.
  • the length of the zone S is approximately half the length of the section Ab and approximately just the length of the output end section which can be immersed in the screw; the remaining length of the intermediate section 10 from the roots 8 "to the step 16 is slightly more than twice the length of this output end section Ab or slightly more than four times the length of the zone S.
  • the length of the intermediate section 10 plus zone S is therefore approximately 11 mm, the one plus the output end section 9 is 17 mm, the one up to the level of the normal screw insertion depth is about 14 mm.
  • the diameter of the middle section is about 4 mm.
  • the intermediate section 10 which is responsible for the torsional rigidity of the corresponding (common tool steel) material
  • the ratio of diameter to length is accordingly 0.3
  • This ratio creates a torsional property which, for the transmission of power from a machine screwdriver to a screw, brings about considerable improvements in that load peaks are cushioned, reaching the torque which leads to plastic deformation or the breaking torque of such screwdrivers
  • This is preceded by a considerable elastic torsion, which has a flattening effect as a restoring torque via considerable rotation angle energy peaks and can be demonstrated by the size of the return rotation angle when the deformation torque or the breaking torque is reached.
  • this reverse rotation angle is 2 degrees; in the solutions designed according to the invention, however, at 3.5-8 degrees.
  • the torsion in use also has the effect that deformation of the screw engagement surfaces of the ribs 8 is prevented.
  • the screwdriver bit 1 is set in such a way that its screwdriver tip 7 positively engages in the Phillips screw 6 of the Phillips screw. If larger energy peaks occur during the screwing in of the Phillips screw, caused e.g. due to a rapid increase in counterforce on the screw, this leads to a torsion of the intermediate section 10 that remains in the elastic range, primarily on its range T. Its torsional section modulus is also smaller than the section modulus against deformation in the screwdriver tip section 9 Energy peaks are accordingly eliminated, so that the screwdriver tip 7 is protected from excessive stress combined with an increased service life.
  • the second embodiment of the screwdriver insert 18 illustrated in FIG. 3 largely corresponds to the configuration described above.
  • the same components are therefore provided with the same reference numbers.
  • an axial cavity 19 extends from the polygonal section 11, which extends over the intermediate section 10 and ends before the tip section 9 or the zone S.
  • a change or adaptation possibility for the torsional modulus of the intermediate section 10 is obtained, so that torsion of the same may occur even at a very low load.
  • a variation in such an embodiment can be obtained by choosing axial cavities of different sizes in diameter.
  • the torsional section modulus of the intermediate section can be determined by its shape and cross-sectional size 6. It is therefore possible to optimally adapt to the most varied of conditions.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Details Of Spanners, Wrenches, And Screw Drivers And Accessories (AREA)
  • Dowels (AREA)

Abstract

A screwdriver bit (1) comprises a terminal drive end region (11) which can be inserted in a chuck (13) of a machine, an intermediate section (10), and a drive region (screwdriver tip section) (9) preferably for recessed-head screws. To facilitate use, the intermediate section (10) forms a T region such that an elastic return force extending over a large reverse angle of rotation is exerted until the torque which results in plastic deformation/rupture is obtained.

Description

Die Erfindung betrifft einen Schraubendrehereinsatz gemäß Gattungsbegriff des Patentanspruchs 1 (siehe 2.B EP-A-0221279)The invention relates to a screwdriver insert according to the preamble of claim 1 (see 2.B EP-A-0221279)

Bei bekannten Schraubendrehereinsätzen (DE-OS 22 31 949) dient eine tordierbare Zone als Sollbruchstelle. Der Zwischenabschnitt bricht bei einem erreichten Soll-Drehmoment. Mit diesen Schraubendrehereinsätzen sollen bei Verwendung in Maschinenschrauber-Futtern keine zu großen Drehmoment-Spitzen übertragbar sein. Der Einsatz ist ein Einwegartikel zum Festziehen von Schrauben. Er ist nur begrenzt einsetzbar.In known screwdriver bits (DE-OS 22 31 949), a twistable zone serves as a predetermined breaking point. The intermediate section breaks when a target torque is reached. These screwdriver bits should not be able to transmit excessive torque peaks when used in machine screw chucks. The insert is a single-use item for tightening screws. It can only be used to a limited extent.

Dem Gegenstand der Erfindung liegt die Aufgabe zugrunde, einen gattungsgemäßen Schraubendrehereinsatz in herstellungstechnisch einfacher Weise so auszugestalten, daß auf den Schraubendrehereinsatz wirkende Drehmomentspitzen zu keiner Verformung des Schraubendreherspitzen-Abschnittes führen, die Lebensdauer erhöht und das Arbeiten mit Maschinenschraubern erheblich erleichtert ist.The object of the invention is based on the object of designing a generic screwdriver insert in a technically simple manner so that torque peaks acting on the screwdriver insert do not lead to any deformation of the screwdriver tip section, the service life is increased and working with machine screwdrivers is considerably facilitated.

Gelöst wird diese Aufgabe bei einem gattungsgemäßen Schraubendrehereinsatz durch das Kennzeichen des Patentanspruchs 1. Die Unteransprüche stellen vorteilhafte Weiterbildungen dar.This object is achieved in a generic screwdriver insert by the characterizing part of patent claim 1. The subclaims represent advantageous developments.

Zufolge derartiger Ausgestaltung ist ein gattungsgemäßer Schraubendrehereinsatz von erhöhtem Gebrauchswert angegeben. Werden am Schraubendrehereinsatz höhere Drehmomentspitzen wirksam, beispielsweise hervorgerufen durch schlagartig einsetzende Antriebs-Kraftspitzen oder durch unterschiedliche Beschaffenheit des die Schraube aufnehmenden Materials, so erlaubt der Zwischenabschnitt zwischen Antriebsendabschnitt und Abtriebsendabschnitt eine elastische Verdrillung/Torsion. Der Zwischenabschnitt stellt ein elastisch nachgiebiges Element mit entsprechendem Rückstellvermögen nach Überwindung der Belastungsspitze dar. Er erträgt größere Momente, und zwar auch bei wiederholter Belastung. Er nimmt dabei Verformungsarbeit auf und speichert sie teilweise in Form potentieller Energie und gibt diese bei Entlastung wieder zurück. Der Zwischenabschnitt wirkt als Dämpfer, so daß Drehmomentspitzen nicht direkt proportional am Schraubendreherspitzen-Abschnitt wirksam werden. Dies macht sich in einer besonders hohen Lebensdauer des Schraubendrehereinsatzes und der Schraube bemerkbar. Zusätzlich sind die Auswurfkräfte reduziert. Bevor der Schraubendreherspitzen-Abschnitt sich verformt oder seinen Einstecksitz zur Schraube verliert, tordiert der Zwischenabschnitt. Je nach Beschaffenheit der Schraubendreherspitze kann der Zwischenabschnitt in seiner Länge und in seinem Querschnitt so gestaltet werden, daß stets etwaige Energiespitzen bei Belastung aufgefangen werden. Günstig ist dabei, wenn das Verhältnis (bei normalem Stahl als Material für den DINgenormten Einsatz) von Durchmesser zu Länge des Zwischenabschnitts im Bereich zwischen 0.5 und 0.2 liegt oder die Länge des Zwischenabschnitts 10 etwa dem 3-fachen Durchmesser entspricht. Eine weitergehende Möglichkeit, das Torsions-Widerstandsmoment des Zwischenabschnittes zu variieren, besteht darin, eine Axialhöhlung im Zwischenabschnitt vorzusehen, die von dem Mehrkantabschnitt ausgeht. Die Axialhöhlung kann zur Änderung/Anpassung des Torsions-Widerstandsmoments des Zwischenabschnitts im Durchmesser unterschiedlich groß gewählt werden und auch unterschiedlich lang. Dies erlaubt es z.B., vom Äußeren her gleichgestaltete Schraubendrehereinsätze mit unterschiedlichen Zwischenabschnitten zu erzeugen, und zwar im Hinblick auf dessen Torsions-Widerstandsmoment. Der Zwischenabschnitt ist vorzugsweise ein gegenüber dem Mehrkantabschnitt stufenförmig abgesetzter Rundabschnitt. Schraubendrehereinsätze zur Übertragung geringer Drehmomente erfordern einen entsprechend durchmesserkleineren Zwischenabschnitt. Diese vielen vorgenannten Variationen gestatten eine optimale Anpassung an nach der Norm bestimmungsgemäßen Einschraubverhältnisse. Auch werden zufolge des Abschneidens der Energiespitzen die Schlitze bzw. Kreuzschlitze in den Schrauben geschont, so daß sie beispielsweise auch bei Bedarf gut herausdrehbar sind.As a result of such a configuration, a generic screwdriver insert of increased utility value is specified. If higher torque peaks become effective on the screwdriver insert, for example caused by abruptly occurring drive force peaks or by different properties of the material receiving the screw, the intermediate section between the drive end section and the output end section allows an elastic twist / torsion. The intermediate section is an elastically flexible element with a corresponding resilience after the load peak has been overcome. It can withstand greater moments, even with repeated loading. It takes up deformation work and partially stores it in the form of potential energy and returns it when the load is released. The intermediate section acts as a damper so that torque peaks are not directly proportional to the screwdriver tip section. This is reflected in the particularly long service life of the screwdriver insert and the screw. In addition, the ejection forces are reduced. Before the screwdriver tip section deforms or loses its insertion seat to the screw, the intermediate section twists. Depending on the nature of the screwdriver tip, the length and cross section of the intermediate section can be designed in such a way that any energy peaks are always absorbed under load. It is advantageous if the ratio (with normal steel as material for DIN-standardized use) of diameter to length of the intermediate section is in the range between 0.5 and 0.2 or the length of intermediate section 10 corresponds approximately to 3 times the diameter. A further possibility to vary the torsional moment of resistance of the intermediate section is to provide an axial cavity in the intermediate section, which starts from the polygonal section. The axial cavity can be selected to have a different size and a different length to change / adapt the torsional resistance moment of the intermediate section. This makes it possible, for example, to produce screwdriver bits of identical design with different intermediate sections, with regard to its torsional resistance. The intermediate section is preferably a round section stepped in relation to the polygonal section. Screwdriver bits for the transmission of low torques require a correspondingly smaller intermediate section. These many variations mentioned above allow an optimal adaptation to screw-in conditions according to the standard. Also, due to the cutting off of the energy peaks, the slots or cross slots in the screws are spared, so that, for example, they can also be easily removed if necessary.

Nachstehend werden zwei Ausführungsbeispiele der Erfindung anhand der Figuren 1-3 erläutert. Es zeigt:

  • Fig. 1 teils in Ansicht, teils im Schnitt eine Kreuzschlitzschraube mit davor angeordnetem Schraubendrehereinsatz im Maßstab 1:1 in DIN-Norm und dahinter dargestellten Maschinenschrauber-Futterfür den Einsatz,
  • Fig. 2 in stark vergrößerter Darstellung (5-fach) den in das Maschinenschrauber-Futter eingesteckten Schraubendrehereinsatz gemäß der ersten Ausführungsform und
  • Fig. 3 eine der Fig. 2 entsprechende Darstellung, betreffend die zweite Aiusführungsform, wobei der Schraubendrehereinsatz eine bis zum Zwischenabschnitt reichende Axialhöhlung besitzt.
Two exemplary embodiments of the invention are explained below with reference to FIGS. 1-3. It shows:
  • 1 partly in view, partly in section, a Phillips screw with a screwdriver bit in front of it in 1: 1 scale in DIN standard and machine screw chuck for use shown behind it,
  • Fig. 2 in a greatly enlarged representation (5 times) the screwdriver bit inserted into the machine screwdriver chuck according to the first embodiment and
  • Fig. 3 is a representation corresponding to FIG. 2, relating to the second form of Aius guide, the screwdriver insert having an axial cavity extending to the intermediate section.

Mit der Ziffer 1 ist ein Schraubendrehereinsatz in DIN-Norm (Größe 2) bezeichnet. Mit diesem kann eine in Fig. 1 veranschaulichte Kreuzschlitzschraube 2 gedreht werden. Letztere setzt sich zusammen aus einem ein Gewinde 3 aufweisenden Schraubenschaft 4 und einem Senkkopf 5, welcher den Kreuzschlitz 6 enthält. Entsprechend dem Kreuzschlitz 6 und der zugehörigen DIN-Norm ist die Schraubendreherspitze 7 gestaltet. Diese besitzt vier in gleicher Umfangsverteilung ange ordnete Mitnahmerippen 8 und bildet damit den Abtriebsendbereich 9 (Schraubendreherspitzen-Abschnitt). An diesen schließt sich ein im Querschnitt kreisförmiger Zwischenabschnitt 10 an, welcher den vorgenannten Schraubendreherspitzen-Abschnitt 9 und den Antriebsendbereich 11 miteinander verbindet. Bezüglich desselben handelt es sich um einen Außensechskant-Abschnitt (ebenfalls entsprechend der zugehörigen DIN-Norm), welcher über eine konische Stufe 12 in den Zwischenabschnitt 10 übergeht. Beim Ausführungsbeispiel entspricht die Länge des Mehrkantabschnittes 11 etwa derjenigen des Zwischenabschnitts 10. Zur Herstellung des Schraubendrehereinsatzes wird Stahl mit federnden Eigenschaften verwendet, beispielsweise Chromnickelstahl. Hergestellt ist er im Wege der Kaltverformung.The number 1 denotes a screwdriver bit in DIN standard (size 2). A Phillips screw 2 illustrated in FIG. 1 can be rotated with this. The latter is composed of a screw shaft 4 having a thread 3 and a countersunk head 5 which contains the cross recess 6. The screwdriver tip 7 is designed in accordance with the cross recess 6 and the associated DIN standard. This has four driving ribs 8 arranged in the same circumferential distribution and thus forms the output end region 9 (screwdriver tip section). This is followed by an intermediate section 10 which is circular in cross section and which has the aforementioned screwdriver tip section 9 and the drive send range 11 connects to each other. With regard to the same, it is an external hexagon section (also in accordance with the associated DIN standard), which merges into the intermediate section 10 via a conical step 12. In the exemplary embodiment, the length of the polygonal section 11 corresponds approximately to that of the intermediate section 10. Steel with resilient properties, for example chromium-nickel steel, is used to produce the screwdriver insert. It is made by cold forming.

Letzeres erlaubt, anders als bei durch reines Abdrehen geformten Einsätzen, die Gestalt, daß die Mitnahmerippen 8 radial weiter nach außen ragen als der Querschnitt (Mantelfläche) des Zwischenabschnitts 10. Sie fallen von einer die äußersten Scheitel 8' verbindenden Umfangslinie wieder ab bis auf die Wurzelpunkte 8", die auf der Mantelfläche des Zwischenabschnitts 10 liegen. Jenseits der die Scheitel 8' verbindenden Umfangslinie, erstreckt sich dadurch eine kurze Zone S, die durch die in den Kernquerschnitt des Zwischenabschnitts 10 reichenden Rinnen zwischen den Mitnahmerippen 8 zwar geschwächt, aber dennoch durch die radial ausladenden Rippenbereiche eine Stabilisierung erfahren haben. Diese vorstehenden Scheitel 8' bringen auch eine Anpassungsfreiheit bezüglich des Zwischenabschnitt-Durchmessers bei gleichen Einsteck-Verbindungsbedingungen zur Schraube. Die kraftübertragende Eindringtiefe in die Schraube reicht im allgemeinen nur etwa maximal über die Hälfte des Abschnitts Ab und ist auch jedenfalls für die Prüfdrehmomente DIN-genormt. An der konischen Stufe 12 vom kreisrunden Querschnitt des Zwischenabschnitts 10 zum Mehrkantabschnitt 11 liegt der elastische Ring 16, angeordnet in einer Innennut 15 des Maschinenfutters 13, an und zieht dadurch den Schraubendrehereinsatz 1 in das Maschinenfutter 13 hinein, bis die Strinfläche 17 am Boden des Maschinenfutters 13 anliegt. Diese Halterung kann wegen des einziehenden Moments erhebliche Toleranzen ausgleichen, was wiederum der Produktion des Einsatzes 1 insgesamt im Wege der (nie so absolut genau durchzuführenden) Kaltverformung entgegen kommt.The latter, unlike in the case of inserts formed by simply twisting off, allows the shape that the driving ribs 8 protrude radially further outward than the cross section (lateral surface) of the intermediate section 10. They fall again from a circumferential line connecting the outermost apexes 8 'to the Root points 8 ″, which lie on the lateral surface of the intermediate section 10. Beyond the circumferential line connecting the apex 8 ′, a short zone S thus extends, which is weakened by the grooves between the driving ribs 8 reaching into the core cross section of the intermediate section 10, but nevertheless These protruding peaks 8 'also provide freedom of adaptation with regard to the intermediate section diameter with the same plug-in connection conditions for the screw. The force-transmitting depth of penetration into the screw is generally only about a maximum of half of the section ts From and is also DIN-standardized for the test torques. At the conical step 12 from the circular cross section of the intermediate section 10 to the polygonal section 11, the elastic ring 16, arranged in an inner groove 15 of the machine chuck 13, bears and thereby pulls the screwdriver bit 1 into the machine chuck 13 until the striking surface 17 at the bottom of the machine chuck 13 is present. This holder can compensate for considerable tolerances due to the pulling-in torque, which in turn accommodates the production of the insert 1 as a whole by means of the cold deformation (which is never so absolutely precise).

Die Gesamt-Länge des dargestellten Schraubendrehereinsatzes 1 beträgt entsprechend der DIN-Norm 25 mm. Diejenige abzüglich des Mehrkantabschnittes etwa 17 mm. Der Zwischenabschnitt 10 (einschließlich des Abschnitts S) und Abtriebsendabschnitt nehmen also ca. 70% der Gesamtlänge des Einsatzes 1 ein. Die Länge der Zone S beträgt dabei ca. die Hälfte der Länge des Abschnitts Ab und etwa gerade die Länge des in die Schraube eintauchbaren Abtriebsendabschnittes; die restliche Länge des Zwischenabschnitts 10 von den Wurzeln 8" bis zur Stufe 16 etwas mehr als das Zweifache der Länge dieses Abtriebsendabschnittes Ab bzw. etwas mehr als das Vierfache der Länge der Zone S. Die Länge des Zwischenabschnitts 10 plus Zone S beträgt also ca. 11 mm, diejenige plus Abtriebsendabschnitt 9 also 17 mm, diejenige bis zur Ebene der normalen Schraub-Einstecktiefe ca. 14 mm. Der Durchmesser des Mittelabschnitts beträgt etwa 4 mm. Das für die Torsionssteifigkeit des aus entsprechendem (üblicher Werkzeugstahl) Material bestehenden Zwischenabschnitts 10 mitverantwortliche Verhältnis von Durchmesserzu Länge ist demgemäß 0,3. Dieses Verhältnis schafft eine Torsionseigenschaft, die für die Kraftübertragung von einem Maschinenschrauber auf eine Schraube erhebliche Verbesserungen bringt dadurch, daß Belastungsspitzen abgefedert werden. Dem Erreichen des zur plastischen Verformung führenden Drehmomentes bzw. des Bruchdrehmomentes solcher Schraubendrehereinsätze geht dadurch eine erhebliche elastische Torsion voraus, die sich als Rückstellmoment über erhebliche Drehwinkel-Energiespitzen abflachend auswirkt und nachweisbar ist über die Größe des Rückdrehwinkels bei Erreichen des Verformungs-Drehmomentes bzw. des Bruch-Drehmomentes. Dieser Rückdrehwinkel liegt bei bekannten Einsätzen bei 2 Grad; bei den erfindsgemäß gestalteten Lösungen hingegen bei 3,5-8 Grad. Die Gebrauchstorsion bewirkt auch, daß eine Verformung der Schrauben-Eingriffsflächen der Rippen 8 unterbunden ist.The total length of the screwdriver bit 1 shown is 25 mm in accordance with the DIN standard. The one minus the polygonal section is about 17 mm. The intermediate section 10 (including section S) and output end section thus take up approximately 70% of the total length of the insert 1. The length of the zone S is approximately half the length of the section Ab and approximately just the length of the output end section which can be immersed in the screw; the remaining length of the intermediate section 10 from the roots 8 "to the step 16 is slightly more than twice the length of this output end section Ab or slightly more than four times the length of the zone S. The length of the intermediate section 10 plus zone S is therefore approximately 11 mm, the one plus the output end section 9 is 17 mm, the one up to the level of the normal screw insertion depth is about 14 mm. The diameter of the middle section is about 4 mm. The intermediate section 10, which is responsible for the torsional rigidity of the corresponding (common tool steel) material The ratio of diameter to length is accordingly 0.3 This ratio creates a torsional property which, for the transmission of power from a machine screwdriver to a screw, brings about considerable improvements in that load peaks are cushioned, reaching the torque which leads to plastic deformation or the breaking torque of such screwdrivers This is preceded by a considerable elastic torsion, which has a flattening effect as a restoring torque via considerable rotation angle energy peaks and can be demonstrated by the size of the return rotation angle when the deformation torque or the breaking torque is reached. In known applications, this reverse rotation angle is 2 degrees; in the solutions designed according to the invention, however, at 3.5-8 degrees. The torsion in use also has the effect that deformation of the screw engagement surfaces of the ribs 8 is prevented.

Jedes Verhältnis Durchmesser zu Länge des Zwischenabschnitts 10, welches kleiner als 0,5 und größer als 0,2 ist, bringt diese erhebliche Verbesserung der abgefederten Belastungsspitzen. Es ergeben sich auch optimale Verhältnisse in Relation zur Zone S, in welcher der Schraubendrehereinsatz abschert, wenn seine Materialbelastungsgrenze, insbesondere bei zu großer schlagartiger Torsion, überschritten wird.Any ratio of diameter to length of the intermediate section 10, which is less than 0.5 and greater than 0.2, brings about this considerable improvement in the cushioned load peaks. There are also optimal conditions in relation to zone S, in which the screwdriver bit shears off when its material load limit is exceeded, especially in the event of excessive sudden torsion.

Zum Eindrehen der Kreuzschlitzschraube 2 wird der Schraubendrehereinsatz 1 derart angesetzt, daß seine Schraubendreherspitze 7 formschlüssig in den Kreuzschlitz 6 der Kreuzschlitzschraube eingreift. Treten während des Einschraubens der Kreuzschlitzschraube größere Energiespitzen auf, hervorgerufen z.B. durch einen schnellen Gegen-Kraftanstieg an der Schraube, so führt dieses zu einer noch im elastischen Bereich bleibenden Torsion des Zwischenabschnittes 10, vornehmlich auf dessen Bereich T. Dessen Torsions-Widerstandsmoment ist auch kleiner als das Widerstandsmoment gegen Verformung im Schraubendreherspitzen-Abschnitt 9. Große Energiespitzen werden demgemäß eliminiert, so daß die Schraubendreherspitze 7 vor zu großer Belastung geschont bleibt verbunden mit einer erhöhten Lebensdauer.To screw in the Phillips screw 2, the screwdriver bit 1 is set in such a way that its screwdriver tip 7 positively engages in the Phillips screw 6 of the Phillips screw. If larger energy peaks occur during the screwing in of the Phillips screw, caused e.g. due to a rapid increase in counterforce on the screw, this leads to a torsion of the intermediate section 10 that remains in the elastic range, primarily on its range T. Its torsional section modulus is also smaller than the section modulus against deformation in the screwdriver tip section 9 Energy peaks are accordingly eliminated, so that the screwdriver tip 7 is protected from excessive stress combined with an increased service life.

Die in Fig. 3 veranschaulichte zweite Ausführungsform des Schraubendrehereinsatzes 18 entspricht weitgehend der vorbeschriebenen Ausgestaltung. Gleiche Bauteile sind daher mit gleichen Bezugsziffern versehen. Abweichend von der ersten Ausführungsform geht nun vom Mehrkantabschnitt 11 eine Axialhöhlung 19 aus, die sich über den Zwischenabschnitt 10 erstreckt und vor dem Spitzenabschnitt 9 bzw. der Zone S endet. Auf diese Weise erhält man eine Änderung bzw. Anpassungsmöglichkeit für das Torsions-Widerstandsmoment des Zwischenabschnitts 10, so daß eine Torsion desselben eventuell schon bei sehr geringer Belastung auftritt. Eine Variation kann man bei einer solchen Ausführungsform dadurch erhalten, daß im Durchmesser unterschiedlich große Axialhöhlungen gewählt werden.The second embodiment of the screwdriver insert 18 illustrated in FIG. 3 largely corresponds to the configuration described above. The same components are therefore provided with the same reference numbers. In a departure from the first embodiment, an axial cavity 19 extends from the polygonal section 11, which extends over the intermediate section 10 and ends before the tip section 9 or the zone S. In this way, a change or adaptation possibility for the torsional modulus of the intermediate section 10 is obtained, so that torsion of the same may occur even at a very low load. A variation in such an embodiment can be obtained by choosing axial cavities of different sizes in diameter.

Weiterhin läßt sich das Torsions-Widerstandmoment des Zwischenabschnitts durch seine Form und Querschnittsgröße 6 bestimmen. Es ist daher eine optimale Anpassung an die unterschiedlichsten Gegebenheiten möglich.Furthermore, the torsional section modulus of the intermediate section can be determined by its shape and cross-sectional size 6. It is therefore possible to optimally adapt to the most varied of conditions.

Claims (7)

1. Screwdriver bit with terminal drive region for insertion in a machine chuck, an intermediate section and a power region having a screwdriver tip (7) which has driving ribs (8) arranged uniformly over the periphery for engagement in cross-slotted screws, the apices (8') of which driving ribs (8) project radially beyond the cross-section of the intermediate section (10), characterised in that the intermediate section has a twistable zone, the ratio of diameter to length of the intermediate section (10) having constant cross-section is less than 0.5 and greater than 0.2 and the torsion modulus of the twistable zone T is such that the restoring angle resulting from the resilient recovery power of the intermediate section (10) to reach the torque leading to plastic defor- mation/break is 3.5 to 8 degrees.
2. Screwdriver bit according to claim 1, characterised in that the ratio of diameter to length of the intermediate section which is about 14 mm long is less than 0.5.
3. Screwdriver bit according to one or more of the preceding claims, characterised in that the ratio of diameter to length of the intermediate section (10) extending to the apices (8') of the ribs (8) is 1:3 and about 1:4 to the tip (9') of the screwdriver bit.
4. Screwdriver bit according to one or more of the preceding claims, characterised by an axial cavity (19) in the intermediate section (10).
5. Screwdriver bit according to one or more of the preceding claims, characterised in that the apices (8') of the driving ribs (8) to their root form a zone S, the dynamic torsional strength of which is less than that of the remaining intermediate section (10).
6. Screwdriver bit according to one or more of the preceding claims, characterised in that the intermediate section (10) of constant circular cross-section extends to a frustum-shaped transition stage (16) at the polygonal section (11), which transition stage occupies only about 1/7 of the length of the intermediate section (10), and on this length brings the transition to the cross-section of the polygonal section (11) which is about twice as large at a cone angle of about 50°.
7. Screwdriver bit according to one or more of the preceding claims, characterised in that the diameter of the intermediate section (10) is greater than the length of the zone S and is somewhat smaller than the length (Ab) of the power end section (9).
EP89104230A 1988-03-10 1989-03-09 Screw driver bit Expired - Lifetime EP0336136B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT89104230T ATE75982T1 (en) 1988-03-10 1989-03-09 SCREWDRIVER BIT.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3807972 1988-03-10
DE3807972 1988-03-10

Publications (3)

Publication Number Publication Date
EP0336136A1 EP0336136A1 (en) 1989-10-11
EP0336136B1 true EP0336136B1 (en) 1992-05-13
EP0336136B2 EP0336136B2 (en) 1998-03-11

Family

ID=6349389

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89104230A Expired - Lifetime EP0336136B2 (en) 1988-03-10 1989-03-09 Screw driver bit

Country Status (6)

Country Link
EP (1) EP0336136B2 (en)
JP (1) JPH02503405A (en)
AT (1) ATE75982T1 (en)
DE (1) DE58901364D1 (en)
ES (1) ES2032619T5 (en)
WO (1) WO1989008536A1 (en)

Cited By (3)

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US8418587B2 (en) 2008-11-07 2013-04-16 Milwaukee Electric Tool Corporation Tool bit
USD711719S1 (en) 2009-11-06 2014-08-26 Milwaukee Electric Tool Corporation Tool bit
US10022845B2 (en) 2014-01-16 2018-07-17 Milwaukee Electric Tool Corporation Tool bit

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4243608C2 (en) * 1992-12-22 2000-10-19 Werner Hermann Wera Werke Tool
US5535867A (en) * 1993-11-01 1996-07-16 Coccaro; Albert V. Torque regulating coupling
BR9408540A (en) * 1994-01-26 1997-05-20 Vermont American Corp Insertion tool and method of producing an insertion tool
DE102010038210A1 (en) 2010-10-15 2012-04-19 Wera-Werk Hermann Werner Gmbh & Co. Kg Torque transmission device for use with a rotary impact driver
US8955418B2 (en) 2013-03-08 2015-02-17 Black & Decker Inc. Threaded fastener driving tool
US11638987B2 (en) 2017-12-01 2023-05-02 Milwaukee Electric Tool Corporation Wear resistant tool bit
USD921468S1 (en) 2018-08-10 2021-06-08 Milwaukee Electric Tool Corporation Driver bit

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2619860A (en) * 1946-08-14 1952-12-02 Jr Ralph E Gray Flexible tool with predetermined overload yielding means
US2501386A (en) * 1947-11-13 1950-03-21 Gibbs George Gordon Portable power transmitting unit and changeable toolholder
DE1603708A1 (en) * 1966-02-17 1970-09-17 Bauer & Schaurte Schrauben U M Procedure for tightening screws
DE2231949A1 (en) * 1971-07-26 1973-02-08 Xerox Corp TORQUE TOOL
SE7316910L (en) * 1973-12-14 1975-06-16 Irvator Ab TORQUE TOOL, SPECIAL TORQUE SLEEVE KEY.
DE3538675A1 (en) * 1985-10-31 1987-05-07 Werner Hermann Wera Werke SCREWDRIVER INSERT

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8418587B2 (en) 2008-11-07 2013-04-16 Milwaukee Electric Tool Corporation Tool bit
US8800407B2 (en) 2008-11-07 2014-08-12 Milwaukee Electric Tool Corporation Method of manufacturing a tool bit
US9849570B2 (en) 2008-11-07 2017-12-26 Milwaukee Electric Tool Corporation Tool bit
US10065294B2 (en) 2008-11-07 2018-09-04 Milwaukee Electric Tool Corporation Tool bit
US11407090B2 (en) 2008-11-07 2022-08-09 Milwaukee Electric Tool Corporation Tool bit
USD711719S1 (en) 2009-11-06 2014-08-26 Milwaukee Electric Tool Corporation Tool bit
US10022845B2 (en) 2014-01-16 2018-07-17 Milwaukee Electric Tool Corporation Tool bit

Also Published As

Publication number Publication date
ES2032619T5 (en) 1998-07-01
ES2032619T3 (en) 1993-02-16
EP0336136B2 (en) 1998-03-11
ATE75982T1 (en) 1992-05-15
EP0336136A1 (en) 1989-10-11
DE58901364D1 (en) 1992-06-17
JPH02503405A (en) 1990-10-18
WO1989008536A1 (en) 1989-09-21

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