US3584172A

US3584172A - Switch operating mechanism

Info

Publication number: US3584172A
Authority: US
Inventors: Kenneth Owen
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-04-01
Filing date: 1969-04-01
Publication date: 1971-06-08
Anticipated expiration: 1988-06-08

Abstract

An electric motor produces oscillating motion for a reciprocating switch by driving a crank having the eccentric crank pin operable in a cam slot having walls on both sides of the crank pin with the slot extending transverse to the direction of the reciprocation and the walls of the slot having concentric portions on opposite walls so the crosshead and the switch actuated thereby will be maintained in both terminal positions even though the crank may stop anywhere within a relatively large angle of approximately 30* and motion arresting means are provided in the form of braking mechanism actuated electrically or stop means of other suitable types while in one form a solenoid operated brake is caused to operate as soon as the electric power to the motor is broken with a diode in the circuit to prevent reenergization of the solenoid actuated brake from the coasting electric motor.

Description

United States Patent Kenneth Owen 6201 Hlbbllng Ave., Springfield, Va. 22150 [2]] Appl. No. 811,920

[22] Filed Apr. 1,1969

[45] Patented June 8, 1971 [72] Inventor [54] SWITCH OPERATING MECHANISM 11 Claims, 6 Drawing Figs.

[52] U.S.Cl. 200/153,

74/50, 307/139, 318/468, 318/212 [51] IIILCI "01h 3/00 [50] Field of Search 307/1120 R, 114, 139, 140; 318/369,468, 467, 372, 383, 212; 335/69, 73; 74/50; ZOO/153.11

Primary Examiner-Robert K. Schaefer Assistant Examiner-H. J. Hobauser Attorney-Milford A. .luten ABSTRACT: An electric motor produces oscillatin'g motion for a reciprocating switch by driving a crank having the eccentric crank pin operable in a cam slot having walls on both sides of the crank pin with the slot extending transverse to the direction of the reciprocation and the walls of the slot having concentric portions on opposite walls so the crosshead and the switch actuated thereby will be maintained in both terminal positions even though the crank may stop anywhere within a relatively large angle of approximately 30 and motion arresting means are provided in the form of braking mechanism actuated electrically or stop means of other suitable types while in one form a solenoid operated brake is caused to operate as soon as the electric power to the motor is broken with a diode in the circuit to prevent reenergieation of the sofenoid actuated brake from the coasting electric motor.

I PATENTEDJuu 8|97l sum 1 0r 2 FIG. 2

INVENTOR. KENNETH OWEN PATENTEDJUN 8|97| 3584.172

sum 2 [1F 2 INVENTOR. KENNETH OWEN BYWQ'.

SWITCH OPERATING MECHANISM The present invention provides power means to actuate a switch'such as the balanced line switch shown in application Ser. No. 628,50l filed Apr. 1, l967 Pat. No. 3,5000,004 and the present invention is adated to operate a switch of the type shown in Wright and Owen Pat. No. 3,223,812.

Although remote control switches are well known switching systems for high frequency switching have not been entirely satisfactory where the individual switches are closely positioned in the manner shown in Pat. No. 3,223,812 and accordingly it is an object of the invention to provide a remote control switch operating switch mechanism which will be satisfactory for switches of this type as well as other types.

Another object of the invention is to provide a switch operating mechanism which assures that the switch will make proper contacts at both limits of movement.

A further object is to provide a motor control and crank system to produce accurate limits of oscillatory movements.

A further object is to provide a motor control with means to arrest the operation of the motor and stop the mechanism of the motor in accurate position.

Other and further objects will be apparent upon reference to the drawings wherein:

FIG. 1 is an isometric view with parts broken away showing motor operating gearing for reciprocating a crosshead member by means of a crank pin operating in a slot in the reciprocating crosshead member with the slot having concentn'c portions to maintain the reciprocating member in accurate position at each limit of movement with the reciprocating member connected to a plunger operating a switch, a brake being applied to the gearing and released by solenoid with a diode in the circuitto prevent energization of the solenoid by the coasting movements of the motor.

FIG. 2 is a perspective of the wiring diagram showing the cam actuation of the limit switches.

FIG. 3 is a diagrammatic illustration of another form using the crank pin and slot for operating the crosshead.

HO. 4 is a section taken on line 4-4 of F IG. 3 showing the different positions of the crosshead showing how the crank maintains the crosshead in the two end positions during substantial arc movement of the crank.

FIG. 5 is a wiring diagram showing the application of direct current to the field of induction motor of FIG. 3 to arrest the movement thereof.

FIG. 6 is a wiring diagram and a crank pin follower of a modification using a reversible motor and positive stop.

Briefly the invention provides electric motor operation of a reciprocating member such as a switch plunger and the electric motor through suitable gearing drives a crank pin which operates in a transverse slot in a crosshead attached to the reciprocating member with the crosshead having portions which are concentric to the axis of rotation of the crank so the reciprocating member will remain stationary at the ends of its reciprocating motion while the crank pin remains in contact with the concentric portions of the slot. In one form of the invention a spring applied brake holds the crank in fixed position and the brake is released by a solenoid which is actuated when the electric motor is operated and cam means are provided on the crank shaft to operate limit switches which interrupt the operation of the electric motor to stop the reciprocating member in proper position. To prevent override caused by the electric motor operating as a generator which would energize the solenoid releasing the brake, a diode is provided in the circuit to prevent current from the motor, which now acts as a generator, from passing to the solenoid and therefore the mechanism stops in its proper place.

In another form of the invention the electric motor is of the AC induction type and the motion arresting means is accomplished by the use of diodes to cause direct current to flow into the field of the induction motor when the AC power to the electric motor is stopped.

in another form of the invention a positive stop in the form of a resilient bumper is placed in the crosshead slot in a position to engage the crank pin and prevent over ride of the crank beyond the concentric portions of the slot and in this form of the invention a reversing type of motor and control is used.

Auxiliary switches are operated by the crank to assure that the power carried by the high frequency switch is turned off prior to breaking the contacts of such high frequency switch and also cam controlled switches indicate the position of the high frequency switch.

Referring more particularly to FIG. 1 of the drawings, a plunger 10 corresponding to a plunger switch contact member of Pat. No. 3,223,8l2 is mounted for reciprocation in a housing which is not shown and the present invention provides a base plate 11 for securement to the front of such a housing by suitable bolts passing through the mounting apertures thereof and extending outwardly from the base 11 are

posts

12, 12 which are secured to a flange 13 or an l-shaped chassis member by suitable bolts 13 and the web 14 of the l member extends outwardly to the outer flange 15 with the base 13 and flange 15 having aligned apertures which receive the guide rods l6, 16 which are parallel to plunger 10 and carry the U- shaped crosshead 17 for reciprocating movement with hairpin type washers 16A abutting the base and plate and engaging grooves in the guide rods to retain the guide rods in position.

An electric motor 18 is positioned below the web 14 and between downwardly extending walls 19 and drives a bevel pinion gear 20 which drives a bevel gear 21 fixed to a shaft 22 rotatably mounted in'web 14 and in a bushing in a removable bottom plate 23. A solenoid case 24 having a coil therein is fixed to the bottom plate 23 by screws and cooperates with a brake disc 25 having a lug 25A extending into a slot in the solenoid case to prevent relative rotation, the brake disc 25 carrying cork friction material for engaging the flat surface of the bevel gear 21, the brake disc being urged into braking contact by the compression coil spring 26.

The shaft 22 carries a spurred gear 27 which meshes with a disc gear 28 rotatably mounted between a flange 29 carried by a bushing member fixed to the web 14; the gear 28 being rotatable on a boss of the bushing member and a washer 29A being held in position on the boss by a screw with plastic type washers between the flange and the retaining washer to maintain the disc gear 28 in accurate operating position meshing correctly with the spur gear 27.

A crank pin 30 is fixed to the gear 28 and carries an antifriction roller 30A which is positioned within a transverse slot 31 in the crosshead 17 so that rotation of gear 28 causes reciprocation of crosshead l7, the slot 31 in the crosshead having

opposite portions

31A, 31A which are concentric with the crank at the periphery of the roller 30A so that the crank may stop anywhere in the

concentric portions

31A, 31A and the crosshead l7 and the plunger 10 will be maintained in the limit or terminal positions. The switch operated by the plunger 10 will be maintained in the limit or terminal positions in either continuing strip line contact or cross strip line contact as disclosed in Pat. No. 3,223,812.

The crosshead 17 is connected to plunger 10 by means of a spool 32 secured to the end of the plunger by a bolt 32A with the spool lying in a slot loosely in crosshead 17 to avoid the necessity for accurate alignment.

An indicator rod 33 is freely slidable through the thicker portion of crosshead 17 and carries

washers

33A, 338 which abut the adjacent ends of the crosshead to move the indicator rods 33 outwardly against the tension of the leaf spring 33C having an aperture therethrough for the rod 33 with hairpin washers on each side to maintain the indicator rod 33 in an intermediate position while the abutment of the

washers

33A or 338 respectively draw the free end 33D inwardly or push it outwardly to indicate that the plunger 10 is in its inner or its outer position respectively.

A single cam 34 of pie-shape with inclined approach and trailing edges is mounted on the underside of disc gear 28 and is adapted to engage the roller contacts of the six micro switches 35, three being shown on one side and the others being hidden by the chassis.

A fuse 36 and a manual switch 37 being shown on the front plate and a diode 38D being shown on the base plate 13, the manual switch serving to manually operate the motor 18 when servicing the operating mechanism.

A crank 38 mounted for rotation in a tubular housing 38A carries a pinion bevel gear 388 which is adapted to mesh with the gear 21 when the housing 38A is fitted into the opening 38C in the front flange 15 so that the switch may be manually operated in case of power failure or during servicing.

Upon reference to FIG. 2 the source or power has one lead permanently connected to one lead of the coil 24 and one lead of the motor 18 whichmotor as shown having a permanent magnetic field and the supply of current being direct current the other lead from the supply is controlled by a remote control switch 39 which may connect to lead 39A or 398 which are connected to switches 35A and 35B respectively which are operated by the cam 34 which engages the actuating levers shown as rods 35A and 358' respectively, the continuation from the switches 35A and 35 B' are connected together and to the diode 38D and from the diode to the other terminal of the motor 18.

In operation when the switch 39 is positioned as shown to connect lead 39A when the switch 35A is closed since the cam is not in engagement with the lever 35A and therefore current passes through the diode to operate the motor 18 and thereby operate the plunger 10 and as soon as the crank pin moves to cause the opposite limit of movement the cam 34 actuates 35A opening the circuit while the switch 358 closes as soon as the cam passes the actuating lever 358'. When switch 35A opens the supply of current is cut off to the motor 18 but the coasting motor would act as a generator and cause energization of the solenoid coil 24 but this is prevented because the diode 38 prevents the reverse flow of current from the motor 18 and therefore the solenoid 24 is not energized and the spring 26 maintains the brake disc in braking contact with the large beveled gear 21 thereby stopping the Plunger 10 with the crank pin in one of the terminal positions in contact with the

concentric portions

31A, or 31A at the opposite sides of the slot 31.

It will be apparent that the l-shaped chassis with the operating mechanism may be removed as a unit by

unfastening bolts

13A, 13A, a plug and receptacle 40 being provided for detaching the supply and control lines, the wiring being omitted in FIG. 1 for clarity of explanation.

It will be apparent that the plunger 10 passes loosely through a bearing 41 in the base 11 and the plunger is also mounted to slide in bearings in the casing shown in Pat. No. 3,223,812 forthe switch with the plunger carrying

stops

42, 42 to limit the motion of the plunger while the connection with spool 32 and the crosshead l7 assures satisfactory operation. A cover box 43 covering the front sides and bottom is V adapted to telescope over the l-shaped chassis to enclose all of the operating mechanism with openings in the front closed end for the fuse 36, switch 37, and operating crank 38, and indicator rod 33.

Referring to the modification shown in FlG. 3 a motor 18A drives a spur gear 27X which drives gear 28X fixed to a crankshaft 28Y which carries a crank arm 282 carrying crank pin 30X rotatably supporting roller 30AX which operates in slot 31X of a crosshead 17X which is slidably supported on guide rods similar to

guide rods

16, 16 previously described and the crosshead is connected to a plunger similar to plunger 10 previously described or to a plunger 21 described in the pending application. The reference numerals used above are similar to those describing the modification of FIG. 1 and 2 with suffixes from the end of the alphabet to distinguish the parts of the two modifications.

For the purpose of illustration the motor 18A is mounted on a base plate '44 and the crank shaft 28Y is rotatably mounted on

struts

44A, 44B and such crank shaft is driven from the motor 18X through a gear reduction unit 45 and a coupling 45A which drives the spur gear 27X. To alternatively drive the crank shaft 28Y, a shaft 46 is rotatably in suitable bearings supported from the base 44 by any suitable means and such shaft carries a beveled gear 46A which meshes with a gear 468 fixed to a shaft 46C which is rotatably mounted in struts 44A and 448 in any suitable manner so that the spur gear 27 carried by shaft 46C is in proper engagement with the gear 28X which drives the crank shaft 28Y and thereby rotates a cam disc 47 carrying cam elements 47A 478 on opposite sides in diametrically opposed relation and which cams operate normally closed

microswitches

47C and 47D respectively.

Referring to FIG. 5 an alternating current supply is provided from a distance through leads 48A and 48B with the lead 488 going directly to an induction motor 18X and the other lead 48A is connected to a double throw single pole switch 488' which has one lead 48C connected to switch 47D and also to a diode 48D which in turn is connected to a resistance and to a lead 485 from the other terminal of the switch 470 and the lead 4815 is connected to the induction motor 18X.

Switch 488' at the remote point may be connected to lead 48F which is connected to switch 47C and to diode 486 which is connected through a resistance to lead 48B and to the other terminal of the induction motor 18X.

Switch 488 at the remote point may be connected to lead 48F which is connected to switch 47C and to diode 486 which is connected through a resistance to lead 48B and to the other terminal of the induction motor 18X.

Assuming the switch is in the position shown upon making contact of switch 488 with lead 48F a supply of current is conducted to the motor 18X and such supply continues to operate the motor until the cam 47A engages the operating member; of switch 47C to thereby open such switch and consequently the supply of alternating current is then stopped since the circuit is broken except for the circuit through diode 486 and the resistance 48H in shunt with switch 47C but the alternating current is changed to direct current as it passes through the diode and therefore applies direct current to the induction motor 18X inducing an arresting action producing a braking action thereby stopping the motor and stopping the crosshead 17X in its upper dotted line position. It will be noted that in the modification of FIG. 1 and FIG. 3, the motor operates in the same direction without requiring reverse operation. To additionally assure that the crosshead 17X stops in the concentric portions, spring pressed balls 49 acting as yieldable detents are provided at the juncture of the straight slot with the concentric portions of the slot.

An indicator rod 33X is fixed to the crosshead 17X and passes through the housing box 43X which covers the movable parts while the stops diagrammatically shown at 49 limit the extent of movement of the crosshead and of the plunger 10X which is connected to the reciprocating switch which is operated by the mechanism of the present invention. The switch operating mechanisms of this invention are adapted to be used in all positions including the vertically reciprocating switch shown in the pending application since the stop means 49 prevents excessive lost motion in both directions and the means for arresting the motion of the motor and the gearing system assures that the crank pin will be maintained in the concentric portions of the slot in the follower.

The plug 50 is connected to a socket or receptacle 51 which is connected by suitable leads to connectors which are adapted to be connected to conventional wiring harness going to the control point and to the indicators showing the position of the switch. The plug 50 is connected through suitable wires not shown in the manner shown in the various wiring diagrams, and provides for removal of the operating unit from the switch board.

It will be noted that the wiring diagrams show plugs and socket connections to provide for the remote control and FIG. 6 shows the modification in which the reversing operation takes place and the cross head cam member 53 is provided with a yieldable stop 54 of rubberlike material which is secured by a screw and washer 56 threaded into the member 53 in the parallel portions of the channel 31 and acts as a stop engaging the roller 30A to stop the gear 28X which carries the corresponding cams 34 and the roller follower 30A. The wiring diagram shows the supply of direct current as having a neutral zero line and a positive and a negative line connected to separate blades of a double single-pole single-throw switch 57 in which only one line can be completed through the connecting socket and plug corresponding to 50 and 51 previously described and the appropriate lead can then go to the corresponding cam controlled switches 1553, 35A and current can go to switches and such switches are operated by the cam 34, the motor 18X which has a permanent magnetic field will alternately reverse when the current is reversed by the corresponding blade of the remote control double single-pole single-throw switch 57 through suitable leads as clearly shown in the diagram of FIG. 6.

It will be evident that in this modification the reversing motor 18X is controlled to move the switch mechanism as described and to'stop the switch at the limit of movement by the engagement of the roller 30A with the rubberlike bumper stop 54.

The positive stop 54 may be of suitable yieldable material and may also be a dash pot or the like.

From the above description it will be evident that the invention provides for operation of a switch in both directions and stoppage of the switch in the limit positions by engagement of roller 30A with stop 54 even with a slight rebound. In this modification the brake 25 and diode 38D may be omitted reducing the cost.

' It will be apparent that changes may be made within the spirit of the invention as defined by the valid scope of the claims.

What I claim is:

1. An operating mechanism for producing controlled oscillatory movement comprising a chassis, a member mounted for a cam mounted on said chassis and adapted to engage said follower and move said member, an electric motor mounted on said chassis for rotating said cam, arresting means to stop said motor and cam after limited movement of said oscillating member, a source of electric power connected to said electric motor, switch means including a diode in the circuit to said electric motor and means to render the diode effective to cause said arresting means to be effective when the operative supply of electric power is terminated to said motor, said arresting means being a spring actuated brake and the brake being released by a solenoid in parallel with the motor circuit and the diode being in a lead directly to the motor and the motor being a direct current motor having permanent field, and the supply of current being direct current.

2. An operating mechanism for producing controlled oscillatory movement comprising a chassis, a member mounted for oscillating movement on said chassis, a follower on said member, a cam mounted on said chassis and adapted to engage said follower and move said member, an electric motor mounted on said chassis for rotating said cam, arresting means to stop said motor and cam after limited movement of said oscillating member, a source of electric power connected to said electric motor, switch means including a diode in the circuit to saidelectric motor and means to render the diode effective when the operative supply of electric power is terminated to said motor, the current supply being alternating current and the motor being an induction motor and a switch supplying current to the motor having the diode and a resistance in shunt with such switch.

3. An operating mechanism for producing reciprocating movement comprising a chassis, a crank rotatably mounted on said chassis and having a crank pin eccentric to the axis of said crank, a crosshead follower mounted for reciprocating movement on said chassis, said crosshead having a crank pin receiving slot extending transversely to the direction of reciprocation, said slot having crank pin engaging walls on opposite sides of said crank pin with some substantial length of wall portion on each wall concentric with the axis of said crank and having another wall portion on each wall forming an elongated channel substantially transverse to the direction of reciprocatmg movement and ofa length at least several times the diameter of the crank pin and an electric motor mounted on said chassis for rotating said crank, motion arresting means for stopping the crank pin in a concentric portion of said crosshead upon limited movement of said crosshead caused by the crank pin moving from one concentric portion on one wall into and out of the elongated channel transverse to the direction of reciprocating movement of the crosshead to the opposite concentric portion on the opposite wall to move the crosshead from one limit position to an opposite limit position whereby when crank pin is stopped in the concentric portions of the slot or the crank pin is moved in the concentric portion of the slot no movement of the crosshead occurs whereby the precise position of the crankpin during starting and stopping in the concentric portions is not critical, whereby the motor is started without load and thereby reaches substantial speed before encountering the load thereby reducing the inrush current to a minumum and assuring reliable starting and operation.

, 4. The invention according to claim 3 in which the motor is controlled by a circuit having a pair of switches in parallel and a cam is driven with the crank to alternately operate the switches to interrupt the flow of current.

5. The invention according to claim 4 in which a doublethrow switch controls the flow of current to the pair of switches.

6. The invention according to claim 5 in which the motor has a permanent field and the supply of current is direct current and a diode is provided in the lead to the motor and the motion arresting means is a spring pressed brake which is released by supply of current to the motor in a parallel connection with the motor.

7. The invention according to claim 5 in which the power supply is alternating current and the pair of switches have a diode and a resistance in shunt with such pair of switches and the motor is an induction motor.

8. The invention according to claim 3 in which the chassis is an l-shaped member having guide rods extending between the base and end and the follower is mounted on such guide rods.

9. The invention according to claim 3 in which the motion arresting means is a yieldable stop adjacent the position of the concentric and transverse portions of the slot and the motor is a reversing motor.

10. The invention according to claim 9 in which the source of power is positive and negative and neutral and switches are provided to causeoperation in opposite directions.

1 1. The invention according to claim 9 in which cam means controls the switches.

Claims

2. An operating mechanism for producing controlled oscillatory movement comprising a chassis, a member mounted for oscillating movement on said chassis, a follower on said member, a cam mounted on said chassis and adapted to engage said follower and move said member, an electric motor mounted on said chassis for rotating said cam, arresting means to stop said motor and cam after limited movement of said oscillating member, a source of electric power connected to said electric motor, switch means including a diode in the circuit to said electric motor and means to render the diode effective when the operative supply of electric power is terminated to said motor, the current supply being alternating current and the motor being an induction motor and a switch supplying current to the motor having the diode and a resistance in shunt with such switch.

3. An operating mechanism for producing reciprocating movement comprising a chassis, a crank rotatably mounted on said chassis and having a crank pin eccentric to the axis of said crank, a crosshead follower mounted for reciprocating movement on said chassis, said crosshead having a crank pin receiving slot extending transversely to the direction of reciprocation, said slot having crank pin engaging walls on opposite sides of said crank pin with some substantial length of wall portion on each wall concentric with the axis of said crank and having another wall portion on each wall forming an elongated channel substantially transverse to the direction of reciprocating movement and of a length at least several times the diameter of the crank pin and an electric motor mounted on said chassis for rotating said crank, motion arresting means for stopping the crank pin in a concentric portion of said crosshead upon limited movement of said crosshead caused by the crank pin moving from one concentric portion on one wall into and out of the elongated channel transverse to the direction of reciprocating movement of the crosshead to the opposite concentric portion on the opposite wall to move the crosshead from one limit position to an opposite limit position whereby when crank pin is stopped in the concentric portions of the slot or the crank pin is moved in the concentric portion of the slot no movement of the crosshead occurs whereby the precise position of the crankpin during starting and stopping in the concentric portions is not critical, whereby the motor is started without load and thereby reaches substantial speed before encountering the load thereby reducing the inrush current to a minumum and assuring reliable starting and operation.

4. The invention according to claim 3 in which the motor is controlled by a circuit having a pair of switches in parallel and a cam is driven with the crank to alternatEly operate the switches to interrupt the flow of current.

5. The invention according to claim 4 in which a double-throw switch controls the flow of current to the pair of switches.

8. The invention according to claim 3 in which the chassis is an I-shaped member having guide rods extending between the base and end and the follower is mounted on such guide rods.

10. The invention according to claim 9 in which the source of power is positive and negative and neutral and switches are provided to cause operation in opposite directions.

11. The invention according to claim 9 in which cam means controls the switches.