NZ536711A

NZ536711A - Rotary selector switch

Info

Publication number: NZ536711A
Application number: NZ536711A
Authority: NZ
Inventors: Horst Biersack
Original assignee: Itw Befestigungssysteme
Priority date: 2003-11-24
Filing date: 2004-11-22
Publication date: 2006-07-28
Also published as: DK1533083T3; DE502004006396D1; DE10355107B3; KR20050050035A; EP1533083A2; ES2301914T3; EP1533083B1; AU2004231227A1; AU2004231227B2; ATE387990T1; EP1533083A3

Abstract

The cam 13 is concentrically mounted to rotary switch 12 and engages in the groove 14 so that when the switch is rotated the cam moves the tube 5 in either axial direction so that one set or the other of splines 6 or 10 is engaged by the tube for different operating modes of a portable drill driven by gear 1 and ring gear 3. Sometimes the splines cannot immediately engage in the corresponding slots. To accommodate this, the cam is mounted on the end of a shaft that is mounted to a spring biased wobble plate so that the cam can pivot under bias in an orbital motion. As soon as the splines can engage the slots the tube will be moved axially under the influence of the biased cam.

Description

<div class="application article clearfix" id="description"> 53 6 7 1 1 - i - NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION After United States Patent Application No. 103 55 107.7-34 filed on 24 November 2003 Davies Collison Cave Reference: 12538340 APPLICANT(S) ITW Befestigungssysteme GmbH Gutenbergstrasse 4, D-91522 Ansbach, Germany My/Our contact address is: DAVIES COLLISON CAVE 1 Nicholson Street G.P.O. Box 4387QQ Melbourne 3000 Victoria, AUSTRALIA Telephone: 61 3 9254 2777 Facsimile 61 3 9254 2770 Email: mai 1 (a'davics.com.au My/Our address for service is: DAVIES COLLISON CAVE c/- James & Wells Level 9, James & Wells Tower 56 Cawley Street Private Bag 11907 DX CP 34005 Ellerslie Auckland NEW ZEALAND INVENTION TITLE: Rotary selector switch We/I. ITW Befestigungssystemc GmbH hereby declare the invention for which we pray that a patent be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: INTELLECTUAL PROPERTY OFFICE OF N.Z. t . V ' » 2 2 I--1-RECEIVED \> •RHC.JMF" UJ.'f. J;.c -hM| ('J la Rotary Selector Switch 5 The invention relates to a rotary selector switch for selecting the different operating functions (drilling-intermediate position-cutting) in a handheld electric tool with an axially displaceable contact tube for the purpose of selecting the operating functions, with the contact tube having transverse profiles to mesh with mating profiles and a circumferential groove which is engaged by an operating 10 cam which is disposed in a plane extending from the rotary switch parallel to the longitudinal axis of the tool and which is rotatable about the switch axis extending transverse to this longitudinal axis. The profiles can for instance be spur gears. When actuating such a rotary selector switch, the problem may arise that the teeth 15 of the spur gears of the contact tube are placed opposite those of the mating profile and thus cannot reach an engagement position so that the switching from the groove position into the position ,,cutting" or into the position ,,drilling" is not possible in this case. The operator is then forced by turning switches at the tool and to achieve by simultaneous multiple actuating of the rotary selector switch 20 that the transverse profile can engage with the respective mating profile. This is laborious and cumbersome. It is the object of the present invention to design a selector rotary switch of the type mentioned at the outset in such a manner that in each case preselection of the 25 desired operating function is possible by turning the switch in such a manner that as soon as the teeth of the transverse profile and the mating profile are able to mesh together, the respective axial displacement is performed and therefore the desired operating function is set. 30 To provide a solution for this problem it is proposed by the present invention that the operating cam be mounted at the rotary switch so as to be pivotally movable in its path of motion on both sides against an elastic force. By virtue of the design in accordance with the invention, actuation of the rotary selector switch in a position in which the profile cannot engage the mating profile - a position therefore in which the corresponding displacement of the contact tube is not possible - allows the operating cam during the turning of the rotary selector switch to be deflected against the biasing spring, whereby the contact tube is biased into the coupling position by the respective elastic force of the restoring spring of the operating cam: as soon as the teeth are moved out of their superimposed position, thus allowing the profiles to mesh, the displacement of the contact tube and the coupling of transverse profile and mating profile arc achieved by this elastic force. In this situation it is obviously in'elevant whether the transverse profiles and mating profiles are defined by meshing bevel gears or toothed gears where one has internal toothing and the other external toothing meshing together upon axial displacement, or whether they consist of some other type of profile. What is decisive is that the profiles are meshing profiles which always run the risk that when misalignment occurs the teeth are superimposed thus preventing coupling. In a further development of the invention it is proposed that the operating cam is arranged at the end of an operating pin disposed parallel to the switch axis with the operating pin being biased by a prctensioned spring and pivotally hinged about its base which has a torsionally stiff connection with the rotary switch. This results in a kind of tumbling movement of the operating pin with the operating cam being disposed at its free end and for this reason preferably provided with a convex annular section to engage the circumferential groove of the contact tube. To achieve this tumbling movement of the operating pin it is proposed by an embodiment of the invention that the operating pin be eccentrically rigidly fastened on a wobble plate which is mounted in a torsionally stiff manner in the switch casing on mutually opposite support elements, centrally between the support points, which wobble plate being impinged upon from above by a compression spring is optionally tiltable about the support elements. To achieve a torsionally stiff connection it is proposed in a very simple manner 5 that the wobble plate be provided with mutually opposite slots which are engaged by the guide elements at the inner wall of the switch casing, which guide elements are flanked by two support elements. By virtue of this simple design of a wobble plate it is achieved that, upon turning 10 the rotary selector switch, - with the selector transverse profile for the operating function in the blocked position where the contact tube is axially blocked after all and the operating cam therefore cannot follow the axially disposed component for the rotation of the selector rotary switch but is retained in the circumferential groove of the contact tube - the wobble plate is deflected by the operating pin 15 such that it lifts off at one support end against the action of the compression spring. As soon as the tooth profiles of the function selection gear are able to mesh, this compression spring causes the return of the wobble plate into its starting position and therefore the displacement of the contact tube into the preselected position. 20 Further advantages, features and details of the invention are explained in the following description of an embodiment example by reference to the drawings. Shown are in: 25 Fig. 1 a perspective detail drawing of a handheld electric tool with the essential gear components for the operating functions drilling and cutting and a selector rotary switch in accordance with the invention which facilitates the switching between these operating functions; Fig. 2 an exploded perspective drawing of the components of the selector rotary switch; 4 Fie. 3 an enlarged cut through the selector rotary switch; Fig. 4 a sectional detail view of the wobble and tilting option of the operating pin and 5 Fig. 5 an enlarged top view of the front face of the selector rotary sw itch with the protruding operating cam. Fig. 1 shows the driven bevel gear 1 of the electromotor gearing of an electric tool 10 in engagement with the bevel gear 3 which, on the other hand, is freely rotatablv mounted on the cylinder 4 which, at its front end (shown on the left in Fig. 1) is connected to a drill. By means of axial grooves and ribs, a contact tube 5 is mounted in a torsionally stiff manner but axially displaceably on cylinder 4, which contact tube 5 is provided at its front end with a spur gear 6 having external 15 toothing which, upon a corresponding axial displacement, can mesh together with the internal toothing of a mating toothed gear, namely the connector ring 8 rigidly mounted in the casing 7. At the other end, the contact tube 5 is provided with a spur gear 9 having internal toothing 10 which can mesh with the external toothing of a mating toothed gear 11 which is permanently connected to the bevel gear 3. 20 If via the selector rotary switch 12 having an eccentric operating cam 13, which engages an annular groove 14 between two fixed rings 15 and 16 of the contact tube, the contact tube is displaced towards the right, the bevel gear is placed in a torsionally stiff connection with the cylinder 4 via the coupled toothed gears 9 and 25 11, via the contact tube 5 having a torsionally stiff connection with the cylinder 4, so that the motor gearing 2 has a rotary connection with the cylinder and therefore with the drill. Therefore, this particular setting is the operating function "drilling". If conversely, the contact tube 5 with the aid of the selector rotary switch 12 30 having been turned by 90 degrees - beyond the OFF position -- in the opposite direction is displaced to the left, the spur gear 6 is couplcd to the connector ring 8 which is fixed within the housing. The contact tube 5 is thereby blocked in the direction of rotation so that in this position only "cutting" can be performed. In accordance with the invention, the rotary selector switch 12 is designed such that a preselection of the functions drilling or cutting is also possible if the actually required displacement of the contact tube 5 is blocked due to the teeth of 5 the meshing spur gears being in superimposed position. For this purpose, a wobble plate 19 is mounted in a torsionally stiff position in the switch casing, with the wobble plate 19 supporting an eccentric operating pin 1 7 being fitted at its end with a convex operating cam 13, in which arrangement the 10 torsionally stiff seating is achieved in that the wobble plate is provided with at least two mutually opposite slots 20 (in the illustrated embodiment example several slot pairs are provided) which are engaged by two mutually opposite guide elements 21 at the inner wall of the switch casing 22. These guide elements 21 are flanked on both sides by support elements 23, on which the wobble plate 19 15 rests, in which arrangement the operating pin 17 with its operating cam is arranged eccentrically on the wobble plate in the middle plane between the supports. The wobble plate 19 is downwardly biased by a helical compression spring 24 and is thereby pressed against the support elements 23. If the switch 12 is turned when the displacement of the contact tube is blocked by way of the teeth 20 of the function selection tooth gear being superimposed, the operating pin 1 7 is tilted by the convex annular section 18 of the operating cam 13, retained in the groove 14, in such a manner that the wobble plate 19 lifts off from one of the supports 23 as is shown in Fig. 4. The operating pin in this arrangement moves in a kind of tumbling movement with its free end within a curved slot 25 of a face 25 plate 26 of the switch casing 22. As soon as the blocking of the contact tube is released by a changed position of the function selection tooth gears 6, 8 or 9,11, the tension applied by the compression spring 24 causes the operating pin with the operating cam to be returned from its tilted position into the starting position and thereby displaces the contact tube axially to achieve the desired function selection 30 coupling. The invention is not limited to the embodiment example shown in the figures. For the functioning of the rotary selector switch having function preselection in 6 accordance w ith the present invention it is merely required that the operating cam 13 can be deflected in the direction of arrow s 27 and 2S as shown in Fig. 5 against the action of a spring, wherein the strength of the spring determines the engagement force by means of which the contact tube displacement during the 5 already described preselection - where the contact tube is being blocked - is achieved and thus the coupling of the selection tooth gears for the various operating functions results as soon as the toothings can mesh together. 10 P-\OPER\JPN\|25WU0 claims dt>c-3(»A J«/f >5 -7- </div>

Claims

<div class="application article clearfix printTableText" id="claims"> Claims

1. A rotary selector switch for selecting the different operating functions (drilling-intermediate position-cutting) in a handheld electric tool with an axially 5 displaceable contact tube for the purpose of selecting the operating functions, with the contact tube having transverse profiles to mesh with respective mating profiles and a circumferential groove which is engaged by an operating cam which is disposed in a plane extending from the rotary switch parallel to the longitudinal axis of the tool and which is rotatable about the switch axis extending transverse to 10 this longitudinal axis, characterised in that the operating cam is mounted at the rotary switch so as to be pivotally movable in its path of motion on both sides against an elastic force.

2. The rotary selector switch in accordance with Claim 1, characterised in that the 15 operating cam is arranged at the end of an operating pin disposed parallel to the switch axis with the operating pin being biased by a pretensioned spring and pivotally hinged about its base which has a torsionally stiff connection with the rotary switch. 20

3. The rotary selector switch in accordance with Claim 1 or 2, characterised in that the operating pin passing through a face plate of the rotary switch is guided in a curved slot.

4. The rotary selector switch in accordance with any one of Claims 1 to 3, 25 characterised in that the operating pin is eccentrically rigidly fastened on a wobble plate which is mounted in a torsionally stiff manner in the switch casing on mutually opposite support elements centrally between the support points, which wobble plate being impinged upon from above by a compression spring is optionally tiltable about the support elements. 30

5. The rotary selector switch in accordance with Claim 4, characterised in that the INTELLECTUAL PROPERTY OFFICE OF N.Z - s SEP 2005 P \0PERJPN\I253J04<> claims doc-3MWW 10 15 -8- wobble plate is provided with mutually opposite slots which are engaged by the guide elements at the inner wall of the switch casing, which guide elements are flanked by two support elements. The rotary selector switch in accordance with any one of Claims 1 to 5, characterised in that the operating cam is provided with a convex annular section to engage the circumferential groove of the contact tube. A rotary selector switch substantially as hereinbefore described with reference to the drawings and/or Examples. Dated this 30th day of August, 2005 ITW Bcfestigungssysteme GmbH by DAVIES COLLISON CAVE Patent Attorneys for the Applicant INTELLECTUAL PROPERTY OFFICE OF M.Z - 6 SEP 2005 RECEIVED </div>