DE1979885U - FOCUSING DEVICE FOR PROJECTORS. - Google Patents

Description

Focusing device for projectors

The innovation concerns a projector with an automatic and another one that can be regulated manually using a remote control Focusing device, both of which are the same Adjusting element (e.g. picture stage or lens) is assigned.

Such arrangements, in which the manually operated focusing device is primarily used, a Nachbzw. Fine adjustment of the sharpness to be able to make in the event that the automatic for some reason does not has brought the desired exact setting are known per se. As setting means are both for the automatic as well as the manual focusing device controls are provided which are in gear connection with the adjusting member stand. These are therefore inevitably coupled to one another in such a way that adjustment by means of the manual focusing device a change in the basic structure for the brings about automatic device.

However, it is desirable and in such automatic focusing devices, parts of which are fixed to the housing are required to return to the starting position after fine adjustment for the subsequent projections for the automatic. This also applies to the orders in which the two focusing devices act on separate actuators.

October 2, 67

Patent department Jg / Ma

To do this, you have to use the controls for the Fine regulation assigned additional gear parts, through which a return of the control elements and thus of the actuator in the starting position is possible. The additional feedback gear is however, especially if it is automatic is designed and automatically comes into operation after each slide change, complicated and therefore expensive.

The task of the present innovation is to achieve the same effect, but with relatively simple means.

In the case of an arrangement of the type mentioned at the outset, this is the result achieved that both focusing devices with independently working control members for the actuator are provided, the simultaneous activation of which is prevented by means of a switch. Duroh the completiff® Separation of the control members of the two focusing devices is avoided that the control members with manual adjustment the other device are moved along. The changeover switch prevents the automatic from being activated at the same time as the Refocusing device works by hand and thus possibly automatically removes any corrections made; it is preferably designed as an electrical switch, through which the energy source or other components located in the circuit for driving the control organs alternately can be switched on and off.

B 2454 October 2nd, 67

Patent department

Year / ma

According to a further innovation, the switch is housed in the remote control part of the projector. It can also be combined with the manual focus switch. This can be done in such a way that a shift lever or shift knob is provided, standing in two mutually perpendicular directions from a rest position serving as a middle layer of bewegba _r.

In the drawing, an embodiment of the innovation is shown. Show it:

Fig. 1 parts of a protector with an automatic as well a manually adjustable focusing device, which can optionally be switched on, in a schematic, circuit-related representation,

Fig. 2 shows a similar arrangement in which the control element «Ent for focusing by hand with the switch

ter is combined,

Fig. 3 »in remote control part for the device according to Fig. 2 in plan view.

The image stage 1 with the inserted slide 2 can be pushed forwards and backwards with respect to the lens 4 by means of a drive consisting of the rack 3 & and the pinion 3b for the purpose of setting the plane of focus. The reversible motor 5 is used to drive the pinion yo · This can be activated by the two control parts I and II using the switch 6.

October 2, 67

Patent department

Year / ma

The control part I contains a switch from a central position can be brought into the positions for forward and backward transport and acts directly on the motor 5. The control part I, like the changeover switch 6, is accommodated in the remote control element 8 shown in dash-dotted lines.

The control part II consists of a known electro-optical Control device in which a measuring beam 9 emitted by a light source 10 after reflection on the slide 2 a two-part photoresistor 11 is fed. This is connected to the motor 5 via the amplifier 12.

The control part II is fixed to the housing and its organs aligned with a basic position (focal plane) do not experience any change when focusing by hand.

Depending on the position of the switch 6 can therefore immediately focusing can be done manually, or the automatic function comes into play. Special means of return are not required.

In Figures 2 and 3, the changeover switch 13 is also a switch for focusing by hand. His adjusting knob 14 can be moved from a central position in two mutually perpendicular directions (arrows 15 and 16).

B 2454 October 2nd, 67

Patent department Jg / Ma

The contacts 17 for the automatic circuit alternating with the contact pairs 18a, 18b for manual focusing closed. With 19 (Fig. 3) is also referred to in the remote control part 20 triggers for the image change.

Claims (3)

Protection claims 1. Projector with an automatic and another, Focusing device adjustable by hand via remote control, both of which the same adjusting element door is assigned the arming, characterized in that that the focusing devices have independently working control members for the adjusting member, their simultaneous ¥ take effect by means of a toggle switch is prevented. 2. Projector according to claim 1, characterized in that the switch is housed in the remote control part. 3. Projector according to claims 1 and 2, characterized in that that the switch is combined with the switch for manual focus.