GB2154745A

GB2154745A - Handle for medical examination instrument

Info

Publication number: GB2154745A
Application number: GB08432229A
Authority: GB
Inventors: Heinz Volkert; Rainer Kirchhubel
Original assignee: Oculus Optikgeraete GmbH
Current assignee: Oculus Optikgeraete GmbH
Priority date: 1984-01-04
Filing date: 1984-12-20
Publication date: 1985-09-11
Also published as: GB8432229D0; DE3400179A1; JPS60222027A

Abstract

A handle 1 for a medical examination instrument 3, such as an ophthalmoscope comprises a power supply for the instrument and an on-off switch comprising a sensor switch 4 having contact areas 5,6 which is turned on when the handle is gripped in the hand. The opposed edges of the contact areas 5,6 are sinuous to provide a long junction which is bridged by the hand. <IMAGE>

Description

SPECIFICATION Handle for medical examination instrument This invention relates to a handle for a medical examination instrument, in particular for an opthalmic instrument. The handle has its own power supply and a switch for switching the instrument on and off.

Handles for instruments of the above-mentioned type are used above all for diagnostic instruments (e.g. opthalmoscopes, otoscopes, oral spatulas). These instruments require their own light source, the instrument's power supply being provided via a battery or via a builtin storage battery or cell. In order to prevent the battery or storage battery from constantly becoming discharged, it is necessary to provide the instrument with a switch for switching off the current source. However, to make the instrument more convenient to handle, it is known to arrange a mercury switch in the instrument, which switches on the light when the instrument is held in the operating position and breaks the circuit when the instrument is set down, for example on a tabletop.

Mercury switches of this type have proved successful, but are not suitable for rechargeable storage batteries or cells if recharging is to be effected without removing the battery or cell from the instrument, i.e. recharging by induction. With this type of device the instrument is inserted vertically into a coil but this arrangement means that the mercury switch constantly closes the circuit, so that the battery is discharged during charging.

The object of the invention is to propose a switch for handles of the type of instrument described above, in which the instrument is switched on automatically when gripped, but in which the circuit is broken when the instrument is set down in any position.

The invention provides a handle for an examination instrument, such as an opthalmic instrument, having a power supply and a switch for switching the instrument on and off, comprising a switch which comprises at least one sensor switch having a large contact surface area, disposed on an outer surface of the handle.

The handle provided on one or more outer sides with a sensor switch, which consists advantageously of two strips of tin, or other suitable conducting metal, which are disposed opposite each other slightly spaced apart.

When the instrument is gripped by hand the circuit is closed, so that the lamp is switched on. It has proved advantageous in this case to form opposed sides of the sensor surfaces in a toothed, grooved or meander-shape, so that a potential contact line with a large surface area is obtained, which can also be reliably bridged by the hand in any position of the instrument.

Known sensor pads are usually triggered by finger contact. However, in the diagnostic instruments of the present type, other operating elements on the diagnostic instrument must be actuated, so that triggering of the sensor pad must be ensured by contact with the palm or the ball of the thumb. By means of the special design of the sensor pad functioning is ensured irrespective of the shape or size of the hand.

The invention will be further described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an instrument with a handle according to the invention; Figures 2 and 3 are side views of the handle of Fig. 1; and Figure 4 is a front view of the handle of Fig. 1.

In the instrument illustrated in Fig. 1, the handle is designated 1 and an ophthalmoscope for ophthalmic examination, which is mounted on top of the handle 1, is designated 2. In known manner, the visuscope 2 (special ophthalmoscope) has means for refraction determination and for determining the foveal or parafoveal fixation. Furthermore, a lamp is arranged in the visuscope. The power supply is provided via a storage battery or cell disposed in the handle 1. The brightness of the lamp is controlled by means of a potentiometer 3, which is also disposed in the handle 1. For switching the visuscope 2 on and off a sensor switch 4 is disposed on the sides of the handle 1, and consists, in each case, of two tin strips 5, 6, which are disposed opposite each other, slightly spaced apart.The lateral edges of the opposed sides of the tin strips 5, 6 are meander-shaped, in order to create a large contact area in a relatively small space, which ensures that a permanent contact, i.e. permanent switching on of the illumination of the visuscope 2, is obtained when the handle is gripped. Figs. 2 to 4 are side views of the said handle, the visuscope 2 having been removed from the handle 1. These figures show that sensor switches 4 are disposed on both sides of the broad, hand-contact areas of the handle 1.

Charging of the storage battery disposed in the handle is effected in known manner by inductions via a winding disposed in the handle and a supply winding. Since the circuit is only switched on when the handle is gripped, the circuit is broken when the instrument has been set aside, irrespective of the position it may occupy, so that the charging of the storage battery built into the handle 1 is ensured.

Claims

1. Handle for an examination instrument, such as an ophthalmic instrument, having a power supply and a switch for switching the instrument on and off, comprising a switch which comprises at least one sensor switch having a large contact surface area, disposed on an outer surface of the handle.

2. A handle according to claim 1, wherein the sensor switch comprises two metal strips which are slightly spaced apart relative to each other.

3. A handle according to claim 2, wherein oppositely disposed sides of the metal strips are toothed, grooved or meander-shaped.

4. A handle according to claim 1, 2 or 3, wherein two switches are provided, one on each of two opposed sides of the handle.

5. A handle for a medical examination instrument, comprising a power supply for the instrument and a switch for connecting the power supply, wherein the switch comprises a sensor switch which is disposed to be closed by the hand when the handle is gripped during use of the instrument.

6. A handle for a medical instrument, substantially as hereinbefore described with reference to the accompanying drawings.