US1224119A - Safety-switch. - Google Patents

Description

A. K. SUTHERLAND.

SAFETY SWITCH.

APPLICATION FILED MAY 4. 1916.

Patented Apr. 24, 1917.

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SAFETY SWITCH.

APPLICATION FILED MAY 4. I916.

Patented Apr. 24,1917.

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fl/ezamie/ufJaMer/and UNITED STATES PAENT OFFICE.

ALEXANDER K. SUTHERLAND, OF NEW BRITAIN, CONNECTICUT, ASSIGNOR TO THE TRUMIBULL ELECTRIC MANUFACTURING COMPANY, OF PLAINVILLE, CONNECTICUT,

A CORPORATION OF CONNECTICUT.

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Specification of Letters Patent.

Patented Apr. 24; 191?.

Application filed May 4, 1916. Serial Ito. 95,299.

To all whom it may concern:

Be it known that I, ALEXANDER K. SUTH- ERLAND, a citizen of the Dominion of Canada, and subject of .King George V, residing at New Britain, Connecticut, have inty e The main object is to provide a construction in which the contacts and fuses or other protective devices are normally inclosed and which cannot be exposed except in the open circuit or ofi position. Another object is to provide a construction of this character which can be locked in the open circuit position so as to prevent the operation of the switch by unauthorized ersons. Another object is to prevent the closing of the circuit when thecontact parts are exposed. Another object is to provide a construction of the. above character having a quick break or circuit opening action.

Figure 1, is a front view of the construction embodying the improvements .of my invention, the cover of the inclosure being shown open. This shows a switch for carrying two lines or both branches of a single line. One fuse is omitted from this figure.

Fig. 2, is a vertical sectional view on the plane of the line 22 of Fig. 1 but showing the cover closed. The switch is shown in full lines in the open circuit position and the operating handle is also shown dotted in the position which it would occupy if locked against movement or if the circuit had been thrown on or closed.

Fig. 3, is a sectional view on a larger.

scale on theplane of the line 33 of Fig. 1 showing the contact operating mechanism.

Fig. 4, is a view similar to Fig. 2 but on a larger scale and showing the switch elements in the closed circuit or on position. This also shows in dotted lines a part of the operating member and a part of the cover in the partially open position.

Fig. 5, is a side view showing a modified form of mechanism for controlling the movement of the switch, the parts being in the open circuit position.

Fig. 6, is a similar view, the parts being in the closed circuit position.

Fig. 7 is a sectional view on the plane of the line 7 of Fig. 5.

Fig. 8, is-a fragmentary view of part of the cover and operating member with an indicator.

The main stationary contacts 10, 10 are preferably inclined toward each other and supported by a suitable insulating base 11. The movable switch member is preferably made in two parts 12, 12 each of which is laminated and carried by an insulating member 13. The switch member 12 is secured to the carrier 13 by a screw 14 which passes through the carrier 13 and the switch member 12 and is screwed into the plate 15.

which is thus interposed between the upper and lower switch members 12, 12. The adacent ends of the switch members 12 may be separated by an insulating barrier 18. The carrier 13 is supported by brackets 20, 20 to which it is secured by screws 20. The brackets are guided by standards 21, 21, each of which has a slot 21 to receive the studs 22 and 23 which are secured to the bracket 20. The spring 24: pulls outward on the brackets so that in the open circuit position the studs .22 are in the outer ends 'of the slots 21. members 12, 12 may be moved to" the closed circuit or on position by means of two arms 25 and 26 hinged together at 27.. and having one end of one hinged at 28 to one standard 21 and the opposite end of the other hinged to the stud 23 of one of the carrier brackets. The tension of the spring 24 when the parts are in the closed circuit position holds the toggle arms pressed against the stop 29.

A stop 30 is mounted on each of the studs 23 and held,v by a spring 31 in the position shown in Fig. 2 where one arm of the stop engages thepin 32 on the arm 26. This .This plate 15 carries a clip 16 for a fuse 17 The carrier 13 and the switch stop makes it impossible to close the switch I the shoulder 35 has been engaged. It is thuspossible when the parts are m the position engages the shoulder 37.

circuit through the switch,

shown in full lines in Fig. 2 to close the switch by simply pulling down on the handle 33 at which time the inner end of the arm 33 engages the shoulder 35 and tilts the stop 30 and then engages the shoulder 36 to move the toggle arms into the position shown in full lines in Fig. 4. To open the the handle 33 is moved upward from the position shown in Fig. 4 so that the inner end of the arm 33 As soon as the toggle arms have been moved so that the connection 27 passes the line of centers between 23 and 28, the spring 24 will throw the switch open with a snap action out of the control of the operator.

The inclosure consists of the box body 40 and the cover 41 hinged at 42. Preferably a. spring catch 43 is secured to the body adapted to project through the slot 44 in the cover as shown in Fig. 2. The end of this catch may be perforated to accommodate the hasp of a padlock 45 for locking the cover in the closed position. The rod 34 is secured in the cover of the box and is engaged by hooks 46 on the arms 25 when the parts are in the position shown in Fig. 4. It is thus impossible to open the cover of the box when the switch is in the closed position as shown in Fig. 4. hen the switch is in the open circuit position as shown in Fig. 2, the hooks 46 are retracted from the rod 34 so that the cover may be opened upon removing the pad-lock 45 and releasing the catch 43. When the cover is closed with the handle in the full line position of Fig. 2, the inner endsof the arms 33 pass between the shoulders 36 and 37 into position to engage the stop shoulders 35 and 36 for releasing the stops and closing the switch.

If the cover of the box is closed with the operating handle in the dotted position of Fig. 2 it will be noted that the inner end of the arm33 does. not pass between the shoulders 36 and 37 but comes above the shoulder 36 and it is thus impossible to move the operating handle and arms so as to operate the switch.

It is of course possible to close the switch manually when the cover is open by retracting the stops 30 with the fingers. If this is done for any .reason and it is then attempted to close the cover the inner end of the operating arms, ifin the dotted position of Fig. 4, will engage-the shoulder 36 and trip the toggle so as to automatically open the switch. If the arms 33 are not moved high enough to engage the stops 36 it is not possible to close the cover with the switch in the closed circuit position since the rodf34 will engage the' hooks 46 substantially in line with the toggle axes.

The contact parts of the switch may be covered by an insulating plate or plates such as 50 so as to prevent accidental engagement therewith when the cover of the box is open. This plate 50 may be secured to lugs 51 on the side ofthe box by means of thumb nuts and studs52.

The slots 53 through which the handle arms 33 extend may be covered by strips 54 held in place by projections 55. The condition of the circuit may be indicated by words on and off on the outer side of the cover, which words are adapted to be covered by a shield 56 movable with one of the strips 54 and the corresponding handle arm so that when for instance the word off is disclosed, as shown in Fig. 8, the circuit will be open and when the word on is disclosed the switch will be closed.

Instead of the toggle arm construction for holding the switch in the closed circuit position I may employ a cam plate 60 such as shown in Fig. 5 which cannot be closed by ordinary pressure because the stud 23' will engage in the notch 61. The cam plate is provided with a shoulder 62 adapted to be engaged by the operating arm 33 (previously described) to move the switch to the closed circuit position. In this movement the cam 63 forces the roller 64 on the stud 23 to the position shown in Fig. 6 and the tension of the spring 24 holds the roller in the recess 65 with the switch in the closed circuit position. vided with a shoulder 66 adapted to beengaged by the inner end of the operating arm 33 (previously described) to open the switch.

What I claim is:-

- 1. In a switch construction, stationary and movable contacts, an inclosure therefor including a movable cover, a hinge member connected to said movable contact and having two shoulders spaced apart from each other and an operating handle pivotally carried by the cover and having an arm adapted to swing between said shoulders when the cover is closed whereby the circuit may be controlled.

2. In a switch construction, stationary and movable contacts, an inclosure therefor including a movable cover, a hinge member connected to said movable contact and having two shoulders spaced apart from each other, an operating handle pivotally carried by the cover and having an arm adapted to swing between said shoulders .when the coveris closed whereby the circuit may be controlled and interlocking parts carried by said hinge member and by said cover for preventing the cover from bein opened when the contacts are in closed circult position.

3. In a switch construction, stationary The cam plate is also proother, an operating handle pivotally carried by the cover and having an arm adapted to swing between said shoulders when the cover is closed whereby the circuit may be controlled and a stop for normally preventing the closing of the circuit, said stop being adapted to be released by said operating arm.

4. In a switch construction, stationary contacts, slotted standards, an insulating carrier, studs projecting from the ends thereof into said slotted standards, members hinged to said standards and having meansof connection with one of the studs in each slot, a stop movable with one of said hinge members and an operating handle for moving said hinge members to close and open the circuit.

5. In a switch construction, a stationary contact, a stationary slotted standard, a carrier having means projecting into the slot of said standard, a contact carried by said carrier, an arm hinged to said standard, a second arm hinged to said first mentioned arm and also hinged to said carrier, one of said arms having two laterally projecting shoulders and a hinged operating member adapted to oscillate between said shoulders, a spring normally tending to pull said carrier so as to separate the contacts and a stop for one of said arms to limit its swinging movement and permit the spring to hold the parts in the closed circuit position.

6. In aswitch construction, a stationary contact, a stationary slotted standard, a carrier having means projecting into the slot of said standard, a contact carried by said carrier, an arm hinged to said standard, a second arm hinged to said first mentioned arm and also hinged to said carrier, one of Silldo arms having two laterally projecting shoulders'and a hinged operating member adapted to oscillate between said shoulders, a spring normally tending to pull said carrier so as to separate the contacts, a stop for one of said arms to limit its swinging movement and permit the spring to hold the parts in the closedcircuit position and a stop movable with said carrier adapted to be automatically closed by said operating member.

. 7. In a switch construction, a stationary contact, a stationary slotted standard,.a carrier having means projecting into the slot of said standard, a contact carried by said carrier, an arm hinged to said standard, a second arm hinged to said first mentioned arm and also hinged to said carrier, one of said arms having two laterally projecting shoulders and a hinged operating member adapted to oscillate between said shoulders, a spring normally tending to pull said carrier so as to separate the contacts, a stop for one of said arms to limit its swinging movement and permit the spring to'hold the parts in the closed circuit position and a stop movable with one of said arms and adapted to be retracted by said operating member.

8. In a switch of the character described, a box and a movable cover therefor, switch contacts supported wholly in the box, switch operating means mounted in the box and an operating handle supported on the cover and movable therewith, said operating handle having an operative connection with the switch operating mechanism freely disengageable therefrom when the cover is opened,

9. In a switch construction, a box and a movable covertherefor, switch contacts mounted wholly in the box, switch operating means mounted in the box, an operating handle mounted on the cover and movable therewith and operating connections ,between said handle and switch operating means disengageable when the cover is open and operatively engageable as the cover is closed only when both the switch operating means and the operating handle are in the open circuit positions.

10. In a switch construction, a box and a movable cover therefor, relatively stationary and movable switch contacts mounted wholly in the box, pivoted levers supported in the box and connected with the movable switch contact for operating the same, an operating handle mounted on the cover and movable therewith and operating connections between said handle and the switch operating levers disengageable as the cover is opened and engageable as the cover is closed.

ALEXANDER K. SUTHERLAND.

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