US2123382A - Timing mechanism - Google Patents

Description

July 12, 1938.

E. J. ROCHER 2,123,382

TIMING MECHANISM Filed May 24, 1934 Patented July l2, 1938 PATENT OFFICE TUNING .MECHANISM Etienne Jean Rocher, Johannesburg, Transvaal, Union ol.' South Africa Application May 24, 1934, Serial No. 727,337 In the Union of South Africa February 1, 1934 4 Claims.

The present invention relates to mechanism adapted to produce a periodic movement the frequency of which is controlled and adjustable, and by means of which a repetitive operation of other devices may be governed.

The invention is suitable for and will be described in reference to flashing an electric lamp signal on a vehicle. Thermostatic switches have been proposed for this purpose but have the dis- 10 advantages that their frequency varies according to changes of temperature to which they are exposed, that they are slow in coming into operation and that they cannot be readily adjusted either as regards their total periodicity or the division of such periodicity into light and dark. It is an object of the invention to overcome these defects.

Timing mechanism according to the invention comprises a reciprocable member, means for imparting a reciprocating movement to said member including an electromagnet (which term is used to comprise a solenoid) and a switch controlling the circuit of the electromagnet and actuated by the reciprocable member so as to cause the reciprocating movement, and means dependent upon a restricted fluid ow for determining the frequency of the reciprocation. The reciprocating member may be moved freely in one direction against a spring; the rate of movement 30 in the other direction being dependent upon the spring pressure and the rate of flow oi the fluid, which may be adjustable.

An example of the invention is shown in the accompanying drawing, in which:

Figure I is a longitudinal View of the mechanism, half sectioned;

Figure II shows electric circuits.

2 indicates a generally U-shaped frame, on which is rigidly secured an electromagnet 3, pref- 40 erably of the kind having annular pole faces 4, 5. Mounted on the magnet is a dished support 6 having a peripheral flange 'I to which are bolted similar flanges 8 of an oppositely dished chamber wall 9 and a needle valve support IU. The parts 1, 9 and I0 are of non-magnetic material.

The reciprocating member comprises a nonmagnetic rod II extending through the electromagnet and a soft iron armature I2 mounted on said rod so as to be in a position to be attracted by the electromagnet. The armature consists of two plates clamping the centre of a ilexible diaphragm I3, the rim of which is clamped between the flanges 'I and 8.

The other end of the rod slides through a cross bar I4 of the frame 2. A collar I5 is mounted on the rod; and between said collar and said bar I4 is a compression spring I6. Said spring is compressed by the movement of the rod I I to the right, when the armature I2 is attracted by the magnet 3; and when the electromagnet is deenergized it restores said rod to the position shown, at which the rod is stopped by a nonmagnetic collar I7 on its coming into contact with the electromagnet. Said collar I'I also functions as a switch-actuating dog and co-operates in this respect with a second dog I8 on the rod I I.

The switch for controlling the electromagnet 3 comprises the insulating sleeve I9 which is freely slidable endwise on the rod II. Said sleeve is provided for part of its length with a metal ferrule 2U in which are formed two annular grooves 2l, 22 separated by an annular rib 23 of V cross sectional form so that its faces 24, 25 are sloped towards the axis of the rod il away from one another. The switch also includes a contact comprising a socket 26 carried on a cross bar 2l' of the frame and having a contracted end 28 which retains a metal ball 29 which is partly projected from said end by a spring 3D. The ball 29 seats in one or other of the grooves 2l or 22 and thereby holds the sleeve I9 in a corresponding position until it is displaced by one or other of the dogs Il, I8, whereupon it snaps into the other one of the grooves and in doing so it exerts a longitudinal force component which propels the sleeve farther in the direction in which the latters movement was started by the propelling dog.

The end 3l of the sleeve nearest the armature exposes an insulating surface. A contact ball 32 yieldingly supported in the same way as ball 29 is positioned to contact either with said insulating surface or with the metallic surface 2G accordingly as ball 29 is in groove 2l or groove 22. The contacts 29 and 32 are provided with binding screws 33 and 34.

The diaphragm I3 forms a movable wall of a chamber 35, the other wall of which is provided by the part 9. Air, or other uid, can freely enter said chamber by way of the inwardly opening ilap valve 36. 31 is the exit orifice for the uid, the effective area of which is adjustably restricted by a needle valve 38 carried by the support ID. 3 9 is a lock nut for the needle valve.

In the example shown, the reciprocating mechanism is arranged to actuate a iiashing switch indicated generallyby 40. This switch comprises an oscillating contact 4I pivoted at 42 and pressed to stationary Contact 43 by spring 44. An arm 45 of the oscillating contact extends into the path of the end of rod II, so that movement of said rod to the right separates the contacts 4l and 43. The contact 43 is carried by a screw 46 mounted in a cross bar tl of the frame 2 and is adjustably secured by a lock nut 48. As contact 63 is screwed to the left, it advances contact il with it and correspondingly shifts the arm away from the end of rod Il. 69 and 66 indicate binding screws for the contacts 6l and 43 respectively.

5l indicates an insulating disc fixed to member l0 and forming part of a manual switch. The movable member of the switch comprises an insulating disc 52 rotatable on the bushing 53 and provided with bridging contacts 54, 55. Said bridging contacts bridge the pairs of contacts 56, 5l and 58, 59, when the handle 60 of member 52 is shifted to the right; and the pairs of fixed contacts 56, 6i and 58, 62 when said handle is shifted to the left. I'he device is mounted on a dash-board 63.

The circuit for the electromagnet is from earthed battery 64, to fixed contact 56, either of fixed contacts 51, 6i onto which the movable contact 56 may pass, magnet 3, contact 29, ferrule 26 and contact 32 to earth.

65, 65 and 66, 66 indicate pairs of signalling lamps arranged at the right and left sides of a vehicle. Either of these pairs can be selected for illumination by the manual switch. The circuit thus comprises battery 6 6, flashing switch lill, contact 58 and either contact 59 and lamps 65 to earth, or contact 62 and lamps 66 to earth.

The operation is as follows: Upon the manual switch being moved to say the right, lamps 65, 65 are illuminated. Electromagnet 3 is energized, attracts armature l2 and4 moves rod il to the right, so compressing spring i6. Air freely enters the chamber 35 through nap valve 36. During this movement rod il contacts with and displaces arm t5, opens contacts 6i, 63 and breaks the circuit of said lamps. Also during the further course of the movement dog il engages sleeve IS causing its rib 23 to displace ball 29 and pass beneath it. The ball presses on the inclined shoulder face 26, nicks sleeve i9 to the right, brings ball 32 onto the insulating surface 3i, and so interrupts the magnet circuit. Spring I6 then returns rod il to the left. The rate of such movement is controlled by the outow of air through orifice 3l, being slower the more the needle valve 38 is screwed in. During the course of this movement, dog i8 engages sleeve i9, pressing its rib 23 beneath ball 29 which thereupon fiicks the sleeve to the left, thus restoring the magnet circuit and causing the operation to be repeated.

The adjustments operate as follows: The period of time occupied by a complete reciprocation of rod H is determined, with a given spring i6, by the degree vof opening of orifice 37. The periods for which the lamps are respectively illuminated and darkened in each cycle of the mechanism are varied by adjustment of the stationary contact 43. Screwing this contact to the left lengthens the period of illumination and vice versa.

I claim:

1. Timing mechanism comprising a reciprocable member, including an armature, an electromagnet positioned to influence said armature for reciprocating the member, a switch controlling the electromagnet and comprising a sleeve freely slidable on the member, spaced dogs on the member adapted to shift the sleeve in the direction of the members movement, said sleeve being formed with a V sectioned shoulder and providing an insulating surface at one end and a conducting surface at the other end, a spring-pressed contact positioned to override the shoulder and shaped to exert a sleeve-propelling force component on the trailing face of the shoulder, means providing constant electric connection with the metallic surface, and means dependent upon restricted fluid flow for determining the frequency of the reciprocation of the reciprocating member.

2. Timing mechanism comprising a reciprocable member, means for imparting a reciprocating movement to it including an electromagnet, spaced dogs on the member, a. switch controlling the circuit of the electromagnet and including a reciprocable part arranged to be moved in opposite directions by said dogs, and means dependent upon restricted uid flow for determining the frequency of reciprocation of the reciprocable member.

3. An electric switch comprising a reciprocable l member, a sleeve freely slidable on said member,-

spaced means on the reciprocable member adapted to engage said sleeve to move the latter with the reciprocable member, said. sleeve being formed with a V sectioned annular ridge and providing an insulating surface at one end and a conducting surface at the other end, a springpressed member positioned to override the ridge and adapted to exert endwise force components on the sloping faces thereof, and an electrical contact positioned to contact alternatively with the insulating surface and the conducting surface.

4. A device adapted to be mounted on the dash board of a vehicle for flashing an electric lamp on the vehicle, comprising a dash-pot casing formed of two casing members having peripheral flanges by which they are secured together, a flexible diaphragm clamped peripherally between said flanges, thev casing members being dished to permit axial reciprocation of the centre of the diaphragm, a needle valve positioned in the axis of the diaphragm, the front casing member providing a seat for said needle valve, said front casing member and the diaphragm enclosing a dash-pot chamber to and from which iiow of air is controlled by the needle valve, a further casing member comprising a peripheral wall adapted to seat in a corresponding aperture in the dash board and a front member advanced from the front dished casing member so that when the device is attached to the back of a dash board by the peripheral flanges aforesaid said front member is advanced towards the front of the dash board, said front member carrying the needle valve, a manual switch mounted on said front member so that it and the needle are accessible at the front end of the device, an electromagnetic motor comprising a stationary member mounted at the rear of the dash pot casing and an elongated reciprocating member attached to the diaphragm and extending axially rearwardly thereof, electrical connections whereby the manual switch controls the motor, a frame extending ETIENNE JEAN ROCHER.

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