DE2303774C3

DE2303774C3 - Device for engaging and disengaging the friction gear of a record player

Info

Publication number: DE2303774C3
Application number: DE19732303774
Authority: DE
Inventors: Manfred; Scheler Holger; Schulz Wolfgang; 2300 Kiel Deisler
Original assignee: ELAC Electroacustic GmbH
Current assignee: ELAC Electroacustic GmbH
Filing date: 1973-01-26
Publication date: 1977-05-05

Description

Steuerscheibe 8, von welcher bekanntlieh alle selbst tat ig ablaufenden Funktionen abgeleitet werden, steuert das Schaltglied 9. Dieses Schaltglied 9 ist im vorliegenden Falle als zweiarmiger Hebel ausgebildet, der um einen Drehpunkt 10 schwenkbar ist.Control disk 8, of which everyone is known to act themselves running functions are derived, controls the switching element 9. This switching element 9 is in the present Trap designed as a two-armed lever which can be pivoted about a pivot point 10.

An der (geschnitten dargestellten) Tonarmachse 11 des Tonarms 12, der hier nur gestrichelt angedeutet ist, ist ein Steuerarm 13 befestigt.On the tonearm shaft 11 (shown in section) of the tonearm 12, which is only indicated by dashed lines here, a control arm 13 is attached.

Das Koppelglied 14 bildet in der gezeichneten Stellung der Vorrichtung mit seinei runden Ausnehmung 15 einen Rastsitz für einen am freien Ende des Schaltgliedes 9 angebrachten Zapfen 16. Etwa gegenüber der Ausnehmung 15, also am breiteren Ende des Koppelgliedes 14, greift ein längsverschieblich gelagerter Zwischenstößel 17 an, über welchen sich der unter der Kraft der Zugfeder 7 stehende Hebelarm 6 abstützt.The coupling member 14 forms in the position shown of the device with seinei round recess 15 a latching seat for a pin 16 attached to the free end of the switching element 9, approximately opposite the recess 15, ie at the wider end of the coupling member 14, engages a longitudinally displaceable mounted Intermediate plunger 17, via which the lever arm 6, which is under the force of the tension spring 7, is supported.

Das schmalere Ende des Koppelgliedes 14 weist ein gekrümmtes Langloch auf, in das der Steuerarm 13 mit seinem Zapfen 19 eingreift.The narrower end of the coupling member 14 has a curved elongated hole into which the control arm 13 is connected its pin 19 engages.

Der Krümmungsradius des Langloches 18 ist zweckmäßig — aber nicht notwendig — gleich dem Abstand des Zapfens 19 von der Mitte der Tonarmachse 11.The radius of curvature of the elongated hole 18 is useful - but not necessary - the same Distance of the pin 19 from the center of the tonearm axis 11.

An dem Zwischenstößel 17 ist im übrigen das Betätigungsorgan 20 des Motorschalters 21 angeordnet.The actuating element 20 of the motor switch 21 is also arranged on the intermediate plunger 17.

Die justierung und die Wikrungsweise der vorstehend beschriebenen Vorrichtung werden nachstehend erläutert: The adjustment and operation of the device described above are explained below:

Die gezichnete Stellung aller Organe entspricht der Ruhestellung des Plattenspielers, bei der der Tonarm 12 ausgeschwenkt ist und auf seiner Ablage liegt, die SteuL-rscheibe 8 ihre sogen. Nullstellung einnimmt, der Motorschalter 21 geöffnet und das Reibrad 2 ausgerückt ist. Der Zapfen 19 des Steuerarmes 13 befindet sich hierbei am äußersten Ende des Langloches 18.The drawn position of all organs corresponds to the rest position of the record player, in which the tonearm 12 is swiveled out and is on its shelf, the control disc 8 their absorbed. Occupies zero position, the Motor switch 21 is open and the friction wheel 2 is disengaged. The pin 19 of the control arm 13 is located here at the outermost end of the elongated hole 18.

Wird nun der Tonarm 12 manuell von seiner Ablage abgehoben, so wird auf die Tonarmachse 11 kein Einschwenkmoment ausgeübt, da das geringe Moment, das der Zwisehens:öße! 17 bezüglich der Rasistelle 15, 16 allenfalls noch auf das Koppeiglied 14 ausübt, sich am Steuerarm 13 lediglich als radiale Zugkraft auswirkt.If the tonearm 12 is now lifted manually from its holder, then there is nothing on the tonearm shaft 11 Swing-in moment exerted, because the small moment that the pinching: size! 17 with regard to the Rasistelle 15, 16 at most still exerts on the head member 14, on Control arm 13 acts only as a radial tensile force.

Um die Einschaltung zu bewirken, muß der Tonarm 12 zur Plattenmitte hin (Richtung des Pfeiles 12j) eingeschwenkt werden, bis der Zapfen 19 das innerste Ende des Langloches 18 erreicht und sodann das Koppelglied 14 mitzunehmen beginnt. Bei dieser Mitnahme wird das Koppelglied 14 aus seiner Raststellung 15, 16 herausgedrängt und gleitet unter der Druckkraft des Zwischenstößels 17 mit der Schrägung, die sich an die Ausnehmung 15 anschließt, an dem Zapfen 16 entlang (in der Zeichnung nach oben). Hierbei folgt der Zwischenstößel 17 der sich zwischen ihm und dem Zapfen 16 verringernden Breite des Koppelgliedes 14. wodurch die Federarbeit der Zugfeder 7 zum Einrücken des Reibrades 2 und zum Schließen des Motorschalters 21 freigegeben wird.To switch on, the tonearm 12 must point towards the center of the record (direction of arrow 12j) be pivoted until the pin 19 reaches the innermost end of the elongated hole 18 and then the Coupling link 14 begins to take along. With this entrainment, the coupling member 14 is out of his Locking position 15, 16 pushed out and slides under the Pressure force of the intermediate plunger 17 with the incline that adjoins the recess 15 on which Pin 16 along (up in the drawing). Here, the intermediate plunger 17 follows between him and the pin 16 reducing the width of the coupling member 14. whereby the spring work of the tension spring 7 to Engaging the friction wheel 2 and closing the motor switch 21 is released.

Da die Bogenlänge des Langloches 18 mindestens gleich der Ersireckung der Schrägung des Koppelgliedes ist, so ist gewährleistet, daß das äußere Ende des Langloches 18 den Zapfen 19 nicht einholt und erfaßt, bevor das untere Ende der Schrägung des Koppelgliedes den Zapfen 16 erreicht hat und die Gleitbewegung des Koppelgliedes beendet ist, so daß auch bei diesem Schnappschallvorgang kein Einschwenkstoß auf den Tonarm ausgeübt wird.Since the arc length of the elongated hole 18 is at least equal to the Ersireckung of the slope of the coupling member, it is ensured that the outer end of the elongated hole 18 does not catch up with the pin 19 and before the lower end of the bevel of the coupling member has reached the pin 16 and the Sliding movement of the coupling member is ended, so that no pivoting impact is exerted on the tonearm during this snap-sounding process.

Beim automatischen Start des Plattenspielers, wobei bekanntlich durch Tastendruck das Anlaufen der Steuerscheibe 8 ausgelöst wird, wird das Schaltglied 9 infolge der Druckkraft des Zwischenstößcls 17 im Uhrzeigersinne verschwenkt, sobald der Nocken 23 der Steuerscheibe 8 die Nase 22 des Schaltgliedes 9 verlassen hat. Hierbei wird somit der Einschaltvorgang durch das Zurückweichen des Zapfens 16 eingeleitet.When the turntable starts automatically, which is known to start the Control disk 8 is triggered, the switching member 9 is due to the pressure force of the Zwischenstößcls 17 im Pivoted clockwise as soon as the cam 23 of the control disk 8 meets the lug 22 of the switching element 9 has left. In this case, the switch-on process is initiated by the retraction of the pin 16.

Hierzu 1 Blatt Zeichnungen1 sheet of drawings

Claims

Patent claims:

1. Device for engaging and disengaging the friction gear of a record player, in which the friction wheel that transmits the rotation of the drive motor shaft to the turntable on a Swivel lever is mounted, the during a playback process by the force of a tensioned spring Friction wheel swivels into an engagement position and keeps engaged and the friction wheel upon termination the playback process swings against the force of the spring in a disengaged position and its Pivoting takes place by actuating an operating element, characterized in that that the pivoting of the pivot lever (4) by acting on a displaceable, wedge-shaped coupling member (14) with an inclined guide surface for the pivot lever (4) takes place, that the coupling member (14) has a wide and a narrow end, which with a constant slope merge into each other and that its displacement from a movement of the tonearm (12) or from the Rotation of a control disk (8) is triggered, whereby the coupling member (14) from a locking position is freed and then, regardless of the tonearm (12) or the control disc (8), by the on the obliquely directed to the guide surface force of the spring (7) experiences a shift, which the Swivel lever (4) m the engagement position of the friction wheel (2) leads.

2. Apparatus according to claim 1, characterized in that the wide end of the coupling member (14) has a latching seat (15) on the side opposite the guide surface, which when the Friction wheel (2) with a locking pin (16) forms a locking mechanism and the pivot lever (4) in the Disengagement of the friction wheel (?) Is supported.

3. Apparatus according to claim 2, characterized in that the coupling member (14) at his narrow end has an arcuate elongated hole (18), the arc length of which is at least equal to The length of the constant slope is and in which one attached to the axis (11) of the tonearm (12) Control arm (13) engages with a pin (19).

4. Apparatus according to claim 3, characterized in that the pin (19) of the control arm (13) in the disengagement of the friction wheel (2) is at the extreme end of the arcuate slot (18) is located and when pivoting the tonearm (12) slides to the inner end of the elongated hole (18) and the Coupling link (14) pushes out of the locking seat (15).

5. Apparatus according to claim 4, characterized in that the loaded by the spring (7) Swivel lever (4) via an intermediate plunger (17) on the inclined guide surface of the coupling link

(14) is supported.

6. The device according to claim 2, characterized in that that the locking pin (16) is mounted on a pivotable switching member (9) which has a the control disc (8) arranged cam (23) scans and which during the rotation of the Control disc (8) the locking pin (16) out of the locking seat

(15) pivots.

The invention relates to a device for engaging and disengaging the friction gear of a record player according to the preamble of claim 1.

Turntables are already known in which the rotation of the drive motor shaft on the turntable is soft transmitting friction wheel mounted on a swivel lever by the force of a tensioned spring is kept engaged and the disengagement of the friction wheel against the force of this spring Moving a switching element (lever or the like.) Takes place, which either by the pivoting movement of the Tonearm or a control arm attached to its axis operated or by a co-driven Cam disk or cam disk (control disk) is guided.

In these known turntables, the friction wheel is thus when the turntable is in the rest position - over the switching element - by one of the tonearm rest on the swiveled out and put down tonearm exerted lateral latching action held out of engagement. This locking effect is known, for example achieved in that the Tonarmab / age as a fork is trained.

However, this arrangement has the following disadvantage: If the tonearm is lifted from its support, that is brought out of its locking position, so to speak, so here the force acting on him is the tensioned spring, which is used to engage the friction wheel, freely and gives him a via the switching element Pivoting torque. If you accidentally lift the tonearm without first pressing the Air lever, or, for example, by shaking the entire device, this is how it is unintentional swiveling, the needle ratchets over the record and possibly the sound corrugation damage, which is known to result in cracking noises when playing the record.

The invention has set itself the task of reducing the reaction of the engagement spring on the tonearm avoid, so make the device reaction-free. This task is achieved by the claim 1 specified invention solved.

Ei ·: Another advantage of the device according to the invention shall look in the fact that also can be carried no transfer of mechanical movements to the Tonarmachse during the execution of the functions necessary for the plate change, the tone arm verharn in out state so that the unsightly "wobbling" tonearm , as it occurs with turntables with positive control , is avoided.

The device according to the invention is explained in more detail below on the basis of the exemplary embodiment shown schematically.

In the drawing, 1 indicates the inner edge of the turntable. 2 is the friction wheel which, in the engaged state, transfers the rotation of the step disk 3 to be thought of sitting on the drive motor shaft to the turntable edge 1 ; it is - as is usual with turntables - mounted on a pivot lever 4 , which in turn is pivotably arranged about the bearing 5.

A lever arm 8 is rigidly connected to the pivot lever 4, and a tensioned tension spring 7 engages this in such a way that it tries to pivot the friction wheel 2 into the engaged position or keeps it engaged.

To thinking also driven from the turntable