US1453024A - Switching mechanism - Google Patents

Description

T. B. FEYON SWITCHING MECHANISM Filed Oct. 23, 1922 Apr. 24,1923.

2/ Z mu m Patented Apr. 24, 1923.

n-rrso srrss TRACY B. RYON, OF WALTHAM, MASSACHUSETTS.

sweet-me MnonAnIsM.

Application filed October 23, 1922. Serial No. 596,209.

To (ZZZ whom 2'25 ma concern:

Be it known that I, TRACY B.' RYoN, a citizen of the United States, residing at lValtham, in the county of Middlesex and State of Massachusetts, have invented a new and useful Switching Mechanism, of which the following is a specification.

This invention relates to mechanism for shifting or switching track members of the type used in overhead industrial conveyor systems. Such systems are used for many purposes and very commonly for conveying molten iron to the diiferent parts of a foundry. In very large plants it is the present practice to provide motor driven cars or p opeller the switching of the cars be ng controlled by the attendant or from a central control station. The switching mech anism heretofore used for such purposeshas often proved defective and unsatisfactory, particularly by failure to properly align the track sections in their different operative positions.

"It is the general objectof my invention to provide improved mechanism for this purpose, by which reliable and eiiicient operation is assured and by which accurate alignment of the track sections is attained.

In the attainment of this general object,

an important feature of invention relates to the provision of a yielding or frictio'nal connection between the 'movable tra cl'r sections and the actuating mechanism therefor.

My invention further relates to a construction by which binding or wedging of the actuating shaft is avoided and to other arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims. i

A preferred form ofmy invention is shown in the drawings, in which I I Fig. 1 is a plan View of improved switching mechanism;

Fig. 2 is an end elevation thereof ;1

Fig. 3 is a detail sectional view'of the friction connection between the actuating shaft and its driving gear; H

V Fig. 4 is an end elevation of the shaft and the adjusting nut thereon; and I Fig. 5 is an enlarged detail elevation of thecircuit reversing mechanism.

Referring to the drawings, I have shown portions of an overhead conveyor system comprising fixed track members 11 and 12, a straight movable track section 13' and a curved movable track section 14. The sections 13 and let are rigidly connected by cross bars 15 and are movable as a unit to align either the section 13 or the section 14 with the track member 10. The section 13, when thus aligned, connects the track member 10 with the straight track member 11 and the section 14 when in operative position connects the track member 10 with the curved track member 12.

A threaded nut 16 is mounted between the cross bars 15 and is a running fit for a threaded actuating shaft. 17 rotatable in bearings in fixed frame members 18 and 19. A motor 20 is connected through a pinion 21 and gear 22 to the shaft 17 and is also connected from the gear 22 through a gear 23, pinion 2 1 and gear 25 to a shaft 26 on which is mounted a circuit reversing arm 27,-the shaft 26 being rotatable in a fixed frame member 28. s

A contact arm 30 is mounted on a pivot 31 and is continuously connected to one line wire 32 of the motor 20. l/Vires 33 and 34: are connected at one end to fixed contact points 35 and 36 with which the contact arm 30 is adapted to engage and at the other end to reversed series field coils 37 and 38. p Tlie field coils 37 and 38 are connected to the contacts 39 and 40 of a starting switch 41 connected through a wire 42 to one of the motor brushes 43. The second brush 44 is permanently connected through a wire 45 to the second line wire 16. The electrical connections described are illustrative only and in themeselves, form no part of my invention. The switch 41 may be manu'algiy, mechanically or magnetically actu-' ate An additional arm 17 is mounted on the pivot 31 and the upper end of this arm eX tends into the path of movement of the re versing arm 27. A spring 48 (Fig. 5) yield ingly connects the outer ends of the arms 30 and 37.

\Vhen the parts are positioned as shown in Fig. 5, the feed wire 32 is connected to the motor 20 through the contact 36 and the wire 34. If the reversing arm 17 is now rotated in the-direction of the arrow a, the arm 27 will eventually engage the arm 47, forcing it to the right in Fig. 5 until the spring 48 passes the axis of the pivot 31. The spring will then act to move the arms 30 and 47 quickly to the position shown in dotted lines in Fig. 5, thus breaking and reversing the motor circuit and connecting the feed wire 32 to the motor through the contact 35 and the wire 33. When the circuit is thereafter manually closed through the wire 33, the motor will be started in the reverse direction and the arm 27 will swing around to engage the opposite side of the arm 47 and throw it from the dotted to the full line position in Fig. 5, thus restoring the original onnections. It will thus be seen that each time that the motor is started, it will operate to give the shaft 26 approximately one single revolution, after which the motor will be stopped and its electrical connections will be reversed.

The gear 22 is yieldingly connected to the shaft 17 by the friction devices shown in Fig. 3. A sleeve 50 is keyed to the shaft 17 and the gear 22 is rotatably mounted on this sleeve. One end of the gear is recessed to receive a friction ring 51 and also a flange 52 on the end of the sleeve 50. At its opposite end the gear 22 is similarly recessed to receive a friction ring 53 and a collar 54 keyed to the sleeve 50 and slidable thereon. The outer end of the sleeve 50 is threaded to re ceive a nut 55 and a spring washer 56 is interposed between the nut 55 and the collar 54:.

The friction between the gear 22 and shaft 17 can be regulated by adjusting the nut 55 on the sleeve 50. I have shown the nut as having a slot 57 at one side and having a locking screw 58 by which it may be firmly clamped in position.

The motor 20 is thus frictionally or yieldvingly connected to the shaft 17 through the gear 20 but is positively connected to the reverse arm 27. The shaft 17 is also provided with flexible spring washers 60 (Fig. 1) and collars 61 on each side of its bearing in the frame member 18, these spring washers being provided for a purpose to be described.

Stops 62 on the track section 13 act to operatively position the section 13 when the stops engage the track members 10 and 11. Stops 63 on the section 14 similarly align this section with the track members 10 and 12.

Having thus described my invention, the method of operation is as follows:

Assuming the parts to be in the position shown in Fig. 1., after the operator has moved the starting switch 41 to the contact 10, the motor will at once rotate the threaded shaft 17 in such a direction as to shift the track sections 13 and 14: from the full line to the dotted line position in Fig. 1, bringing the section 14 into operative position. When this position is reached, the stops 63 will engage the track members 10 and 12, preventing further movement of the section 14. The motor 12, however, will continue to revolve, such action being permitted by the frictional yielding connection between the gear 22 and the shaft 17. The motor will thus continue in operation until the arm 27 has engaged the arm 47 and reversed the position of the arms 47 and 30, breaking the motor circuit and reversing the series field coil connections and 36.

To restore the track sections to their initial relations, the switch 41 is thrown from the contact d0 to the contact 39, thus completing the circuit through the reverse field coil 37 and causing the motor to revolve the shaft 17 in the opposite direction.

The spring washers 6O permit a slight yielding movement of the shaft 17 as the stops 63 are engaged, thus cushioning the shaft and preventing it from becoming wedged too tightly in the nut 16. With this construction the shaft 17 is more easily started in the reverse direction than would be the case with a positive thrust bearing.

The operative position and alignment of the track sections is thus determined entirely by the rigid stops 62 and 63 and is not dependent upon the stopping the motor 20 at some predetermined point, as has been heretofore attempted.

Having thus described my invention and the advantages thereof, 1 do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is 1. A switching mechanism comprising a pair of track sections, means to shift said sections alternatively to operative positive position, positioning devices for said sections, driving mechanism for said shifting means, effective to move said track sections against one or the other of said positive positioning devices and means thereafter engaged by the continued operation of said driving mechanism effective to stop said mechanism.

2. A switching mechanism comprising a pair of track sections, means to shift said sections alternately in opposite directions, said means including a motor, a circuit controlling switch for said motor, positive driving connections between said motor and said circuit controlling switch, and yielding driving connections between said motor and said track sections.

3. A switching mechanism comprising a pair of track sections, means to shift said sections as a unit to operatively position said sections alternately, driving mechanism for said means, means to limit such shifting movement, a yielding device permitting said driving mechanism to over-run its positioning operation, and controlling means becommg operative during such over-run to stop said driving mechanism.

at. A switching mechanism comprising a pair of track sections, means to shift said sections as a unit to operatively position said sections alternately, driving mechanism for said means including a reversible motor, a device permitting said motor to over-run its positioning movement, and means to stop said motor during such over-run after a predetermined period of operation and independent of the movement and position of said track sections.

5. A switchingmechanism comprising a pair of track sections, means to shift said sections as a unit to operatively position said sections alternately, driving mechanism for said means including a reversible motor, a

device permitting said motor to 0ver-run its positioning movement, and means to stop said motor during such over-run after a predetermined period of operation and independent of the movement and position of said track sections and to simultaneously reverse the circuit connections thereof.

6. A switching mechanism comprising a pair of track sections, a threaded shaft connected to shift said sections, stops to operatively position said sections, driving means for said shaft, a yielding connection between said driving means and said shaft, and means to yieldingly position said shaft axially.

In testimony whereof I have hereunto afiixed my signature.

TRACY B. RYON.

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