GB2206737A - Switch - Google Patents

Abstract

A switch, especially for a portable flashlight, is operated by a shaft 12, successive depression of which alternately opens and closes the switch contacts (3, 4; Fig. 1). As described, the shaft has an upper part carrying projections 14t and a lower part carrying projections 14b. Depression of shaft 12 causes projections 14t to push projections 14b downwards so that the lower part of the shaft closes the switch contacts. Projections 14b slide in a first set of slots 13. On clearing the bottom of these slots, the projections 14b rotate slightly so that when shaft 12 is released, a spring 15 pushes projections 14b upwards but into a second, shorter set of slots which arrest their movement. When shaft 12 is depressed again, projections 14b move into the first set of slots, so that on release of shaft 12, full upward movement of projections 14b is possible, and the switch contacts spring open. <IMAGE>

Description

A SWITCH DEVICE FOR A PORTABLE LIGHTING EQUIPMENT Field of the Invention The present invention relates to a switch device for a portable lighting equipment, and more particularly relates to an improvement of assembling the switch device to the portable lighting equipment.

Statement of the Prior Art A conventional portable lighting equipment such as a flashlight shown in Fig. 4 has a sheath composed of a casing C made of a synthetic resin. The casing C receives a bulb L, a battery B, a lighting circuit W and the like. A switch device S which turns on and off the lightening circuit W is provided on the casing C near a grip T provided on the casing C. A user can operate the switch device S to turn on and off the bulb L while grasping the grip T.

One of the conventional switch devices is shown in Fig. 5. The switch device S has two push buttons SA and SB covered by a flexible cover V. Each of the push buttons SA and SB extends inwardly through the casing, C and contacts with a contact DA which is pivotally supported by a curved leaf spring P on the casing C and connected in a lever manner and contact DB. The heads of the push buttons are connected with each other by a leaf spring P. The lever DA can selectively contact with a fixed contact DB.

Uhen one of the push buttons SA and SB is pushed down (for example, push-button SA in Fig. 5), the other button (for example, button SB) is pushed up by the leaf spring P and one of the lever DA (for example,the left end thereof in Fig. 5) contacts with the fixed contact DB. Thus, the lighting circuit W turns on.

Similarly, when the other button (for example, button SB) is pushed down, the end of the lever DA disengages from the fixed contact DB and the lightinq circuit W turns off.

In the conventional switch device, it is necessary to accommodate the push buttons SA and SB, leaf spring P, lever DA and fixed contact DB in the narrow space in the casing C. Accordingly, it is difficult and complicated to assemble and work the elements in the casing C.

Summary of the Invention An object of the present invention is to provide a switch device for a portable lighting ~ equipment which is easy and convenient to assemble and work the elements in the casing of the equipment.

According to the present invention, the object is achieved by the provision of a switch device for a portable lighting equipment wherein a lighting circuit is disposed in a casing forming a sheath of said equipment and said switch device is provided on said casing so that a switch turns on and off said lighting circuit, characterized in that; a means for operating said switch utilizes a push latch mechanism in which an actuating shaft projected out of said casing is selectively displaced between two positions only by pushing said shaft; said push latch mechanism is fixed to said casing with a portion of said mechanism being protruded from said casing; and contact pieces of said switch are provided on the line of displacement of said shaft in said casing.

In the switch device for a portable lighting : device according to the present invention, since the compact push latch mechanism is utilized as an operational unit for the switch, it is easy and convenient to assemble and work the switch device in the casing of the lighting equipment.

Many other advantages, features and additional objects of the present invention will become apparent to those skilled in the art upon making reference to the detailed description and the accompanying drawings on which preferred structural embodiments incorporating the principles of the present invention are shown only by way of illustration.

Brief Description of the Drawings Fig. 1 is a cross section of a switch device for a portable lighting - equipment according to the present invention; Figs 2 and 3 are cross sections of a portion of the switch device showing the operations thereof; Fig. 4 is a side view of a conventional portable lighting equipment; and Fig. 5 is a cross sectional view of a conventional type thereof.

Detailed Description of the Preferred Embodiments One of the preferred embodiments according to the present invention is now described in detail referring to Figs 1 to 3.

In Fig. 1, a push latch mechanism 1 is fitted in a bore CA formed in a casing C. The push latch mechanism 1 serves as an operational unit for a switch S.

The push latch mechanism 1 comprises a cylindrical body 11 and an actuating shaft 12 which is inserted into the body 11 along the axis thereof so that the upper and lower ends are projected through the body 11. A plurality of sliding slots 13 with a serrated shape are formed on the internal wall of the body 11. The actuating shaft 12 has projections 14 which slide in the slots 13. A coil spring 15 is disposed between the body 11 and the shaft 12 so that the spring 15 biases the shaft 12 against the body 11.

Referring now to Figs 2 and 3, the relationship between the slots 13 and projections 14 and between the shaft 12 and the projections 14 are explained in more detail. The depth of the slots 13 are small and large alternately, as shown in Fig. 3A. The actuating shaft comprises an upper shaft and a lower shaft 12b.

The upper shaft 12t has a projection 14t while the lower shaft 12b has a projection 14b. The projection 14t engages with the projection 14b (see Fig. 2). When the upper shaft 12t is pushed down, the projection 14t moving down with the shaft 12t pushes down the projection 14b.

Consequently, the lower shaft 12b is pushed down (see Fig. 2B).

The movement of the actuating shaft 12 is explained below in connection with the projections 14t, 14b and the sliding slots 13.

The actuating shaft 12 is pushed down from the position shown in Fig.

2A to the position shown in Fig. 2B. Consequently, the projection 14t pushes down the projection 14b. When the projection 14b passes through the lower end of the sliding slots 13, the projection 14b slightly rotates towards right as shown in Fig. 3B. Then, if the pushing force to the shaft 12 is released, the projection 14b is pushed up by the spring 15 (see Fig. 2C). At this time, since the slant of the upper end of'the projection 14b engages with the slant of the lower end of the slots 13, the projection 14b is further rotated towards right while moving up to enter into the adjacent slot 13 having small depth.

The projection 14b engages with the bottom of the shallow slot 13 and stops moving (see Figs 2C and 3C). Similarly, the projection 14b novels from one of the slots 13 to the adjacent slot 13 one after another by pushing and releasing the shaft 12.

It should be noted that the push latch mechanism is not limted to the structure described above. That is, it is enough that the shaft may alternatively ascend and descend upon pushing the shaft 12.

Since the push latch mechanism 1 is fitted in or fixed, if necessary, by bonding agent to the bore CA, one end of the actuating shaft 12 extends outwardly from the casing C while the other end extends inwardly in the casing C.

A cover 2 made of rubber etc. is attached to the one end of the shaft 12 extending outwardly from the casing C to seal the casing C.

A concave CB is formed on the casing C around the cover 2 so that the cover 2 may not obstruct and actuate accidentally. Contact pieces 3 and 4 are provided under the shaft 12 in the casing C. The contact piece 3 is supported on the inner wall of the casing C in the way of a conventional cantilever. The contact piece 4 is secured on the inner wall of the casing C.

When the cover 2 is pushed doun, the actuating shaft descends to the position shown by the imaginery line in Fig. 1 to engage the contact piece 3 with the contact piece 4. In this state, the cover 2 is further pushed down, the actuating shaft rises to the position shown by the solid line in Fig. 1. Consequently, the contact piece 3 disengages from the contact piece 4 by its elasticity.

It will be apparent from the above description that the switch device of this invention can be fitted on the casing C outwardly Accordingly, it is easy to assemble and work the switch device on the casing. Isn addition, the structure of the contact pieces becomes simple since the operational unit for the switch utilizes the push latch mechanism.

Such improvement of assembling and working increases the efficiency in manufacturing the portable lighting equipment and decreases the cost of manufacturing.

From the foregoing description of an illustrative embodiment, those of ordinary skill in the art may be capable of accomplishing many modifications from the showing of the accompanying drawings but still residing within the spirit and scope of the present invention.

For example, it may be profitable to employ some of the devices of the present disclosure while substituting different designs for other parts. It is accordingly not intended that the foregoing description and accompanying drawings be taken in a limiting sense but rather that the scope of the invention be interpreted in terms of the appended claim.

Claims (15)

1. A switch device including a reciprocally mounted actuating portion, pushing and releasing of the actuating portion being arranged to cause reciprocal movement of the actuating portion selectively between a first position and a second position, the first and second positions being displaced from each other In the direction of reciprocal movement.

2. A switch device as claimed in Claim 1 In which repeated pushing and releasing of the actuating portion is arranged to cause reciprocal movement of the actuating port Ion alternately between the first and second positions between successive reciprocal movements of the actuating portion.

3. A switch device as clalmed in Clalm 1 or 2 In which the actuating port Ion is arranged to pivot about an axis coincident with the direction In which It Is arranged to reciprocate, when moving between the first and second positions.

4. A switch device as claimed In Claim 3 In which the pivotal movement of the actuating portion is arranged to be in a common directlon when moving between successive first and second positions.

5. A switch device as clalmed In Claim 3 or 4 in which the actuating portion Is mounted in a housing, and the pivotal movement of the actuating portion Is arranged to be effected at least partly by cooperatlon of a part fIxed relative to the housing with a part of the actuating portion.

6. A switch device as claimed in Clalm 5 In which the actuating portion protrudes from the housing.

7. A switch device as clalmed In any preceding clalm Including a reciprocally mounted operating portion which, when the operating portion Is pushed, Is arranged to push the actuating portion. r

8. A switch device as clalmed in ClaIm 7 In which the operating portion Is mounted In a housing and the operating portion protrudes from the housing.

9. A switch device as clalmed In Clalm 7 or 8 In which the operating port Ion and the actuating portion are mounted In a housing, and pivotal movement of the actuating portion Is arranged to be effected at least partly by cooperatlon of part of the actuating portion with part of the operating portion.

10. A switch device as clalmed In Clalm 5, 6 or 9 in which, when the actuating portion is In one of the fIrst or second positions the actuating portion abuts a part fIxed relative to the housing to prevent movement of the actuating port Ion In one direction of reciprocal movement.

11. A switch device as claimed In any preceding claim In which blasing means are arranged to exert a force on the actuating portion to at least partly oppose movement of the actuating portion caused by pushing the actuating portlon.

12. A switch device for a portable lighting equipment wherein a lighting circuit Is disposed In a casing forming a sheath of said equipment and said switch device Is provided on said casing so that a switch turns on and off said lighting circuit, characterlsed in that; means for operating said switch utlllses a push latch mechanism In which an actuating shaft projected out of said casing is selectively displaced between two positlons only by pushing said shaft; said push latch mechanism is fixed to said casing with a portion of said mechanism being protruded from said casing; and contact pieces of said switch are provided on the line of displacement of said shaft In said casing.

13. A switch device substantlally as hereln described with reference to, and as shown In any of Flgures 1 to 3 of the accompanying drawings.

14. Portable lighting equipment Including a switch device as claimed In any preceding clalm.

15. Portable lighting equipment as clalmed In Clalm 14 in which the switch device Is mounted on a casing of the equipment and contact pieces of the switch are provided In the casing at least one of which contact pieces are In the line of reciprocal movement of the actuating portion.