US1730311A - Narrow-type panel main switch - Google Patents

Narrow-type panel main switch Download PDF

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Publication number
US1730311A
US1730311A US197388A US19738827A US1730311A US 1730311 A US1730311 A US 1730311A US 197388 A US197388 A US 197388A US 19738827 A US19738827 A US 19738827A US 1730311 A US1730311 A US 1730311A
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Prior art keywords
cam
switch
operating handle
moved
narrow
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Expired - Lifetime
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US197388A
Inventor
Harold G Baxter
Hubert K Krantz
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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Priority to US197388A priority Critical patent/US1730311A/en
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H19/00Switches operated by an operating part which is rotatable about a longitudinal axis thereof and which is acted upon directly by a solid body external to the switch, e.g. by a hand
    • H01H19/54Switches operated by an operating part which is rotatable about a longitudinal axis thereof and which is acted upon directly by a solid body external to the switch, e.g. by a hand the operating part having at least five or an unspecified number of operative positions
    • H01H19/60Angularly-movable actuating part carrying no contacts
    • H01H19/63Contacts actuated by axial cams

Definitions

  • Our invention relates to switch mechanism and particularly to switch mechanism used for controlling the main circuit of a distributin panel.
  • One object of our invention is to provide a main switch for a distributing panel that is relatively shallow in depth and does not require a deep panel housing.
  • Another object of our invention is to provide a switch of the brush type that is moved into closed position by means of a rotary cam and which is opened by a snap action in response to movement of an operating handle.
  • a further object of our invention is to provide a switch having the above noted characteristics wherein the construction is rugged and wherein relatively great contact pressure can be applied to the switch brushes with little effort, and wherein the contact pres sure is maintained while the switch is in closed position.
  • Fig. 2 is a bottom plan view of the switch device shown in Fig. 1 with the operating handle in the off position;
  • Fig. 3 is a bottom plan View of the switch mechanism showing the position of the operating handle and the cam when the switch is in the on position;
  • Fig. 4 is a longitudinal section through the switch mechanism taken on the line IV-IV of Fig. 5;
  • Fig. 5 is a longitudinal section of the switch mechanism taken on the line VV of Fig. 1;
  • Figs. 6 and 7 are bottom plan and elevational views, respectively, of the operating cam.
  • Fig. 8 is a developed view of one of the cams shown in Figs. 6 and 7.
  • the switch mechanism comprises a base plate 9 that is attached to an insulating base 10 secured to the rear wall 11 of a panel housing.
  • supporting rods 12 are riveted to the base plate and serve to support a cover plate 13 that is spaced from the base plate 9 by means of compression tubes 14, the cover 13 bein securely attached to the rods 12 by means 0% threaded nuts 15.
  • the switch illustrated is a three-pole switch and is provided with three laminated contact brushes 16 comprising copper strips that are clamped between insulating bars 17 constituting the switch contact carrier, by means of bolts 18.
  • the insulating bars are provided with perforations 19 and slide upon the bushings 14.
  • Springs 21 disposed between the base plate 9 and the bars 17 serve to yieldingly bias the switch brushes and carrier to ward open position as shown in Fig. 5.
  • the brushes 16 are adapted to engage the contact terminals 22 that are mounted on insulating blocks 23 secured to the insulating base 11.
  • the bushings 14 serve as a guide for the switch contact carrier which is moved inwardly by means of a rotary cam 24 consist ing of two semi-cylindrical cam wings 25 and an end plate 26.
  • cam 24 is illustrated in detail in Figs. 6, 7 and 8 and it will be noted that the cam Wings 25 are provided with cam surfaces 27 that are inclined from the end plate 26 and terminate in a slight depression 28, the purpose of which will hereinafter appear.
  • the cam 24 is pivoted for rotation upon a shaft 29 which is rotatably mounted in the cover plate 13 and is fixed to an operating handle 31.
  • the shaft 29 and the cam 24 are retained in assembled relation by means of a washer 32 that is attached to the inner end of the shaft 29 which is riveted over the washer.
  • the cover 13 is provided with an arcuate slot 33, Figs. 1, 2 and 3, through which a pin 34 attached to the handle 31 extends.
  • the end plate 26 of the cam is also provided with an arcuate slot 35 through which the pin 34 also extends.
  • the operating handle and the cam are yieldingly connected to one another by means of a spring 36 that is attached at one end to the inner end of the pin 34 and to one of the cam wings 25, the end of the spring being inserted through holes 37 in the cam wing as indicated in Figs. 3 and 4.
  • Anti-friction rollers 38 are rotatably mounted on pins 39 supported in yoke brackets 41 that are attached to the insulating bars 17 by means of rivets 42.
  • the rollers 38 are aligned with the cam faces or edges of the cam wings 25 and ride over the edges when the cam 24 is rotated.
  • the switch is moved to closed position by moving the operating handle 31 from the position shown in Fig. 2 to the position shown in Fig. 3.
  • the pin 34 engages the right-hand end of the slot 35 and rotates the cam wings 25 counterclockwise as in Figs. 2 and 3 with the operating handle. .Rotation of the cam wings 25 causes the rollers 38 to ride on the cam faces and depress the brush contacts into engagement with the contact terminals 22 as shown in Fig. 4.
  • the rollers move into depression 28 on the cam faces and serve to retain the cam in the closed position shown in Fig. 4.
  • the spring 36 will cause the cam to rotate with a snap motion to the open position shown in Figs. 2 and 5.
  • the compression springs 21 will immediately cause the brush contacts to move to open position with a. snap action. may then be repeated.
  • the switch is shown as mounted in a panel housing having a bottom wall 11 and a cover or trim 46 having an opening -7 through which the switch cover 13 projects.
  • the panel is provided with a movable door 48 which serves to close an opening over the fuse receptacles (not shown) within the panel housing.
  • Doors of this character are usually provided with a bar latch forretaining the door in closed position, the ends of the bar or bars being movable under the trim adjacent the corners of the, door to lock it in closed position.
  • the latch comprises a bar 49 that is slidably mounted on the inner side of the door'48 and which is provided with an inwardly extending tongue 1 that projects through the notch 52 provided in an interlocking plate 53.
  • the purpose of the interlocking plate is to prevent opening movement of the latch so long as the switch is in closed position and to prevent closing movement of the switch until the door has been closed and the latch moved to locking position.
  • the interlocking plate 53 is slidably mounted on the inner side of the switch cover 13 and is secured in position by meansof rivets 54 that extend through slots 55 in the plate 53.
  • the interlocking plate 53 is provided with an extension 56 having a finger 57 that projects toward the inner side of the cover 13 as indicated in Figures 2, 3 and 4.
  • the cam 24 is provided with an angular notch 58 which permits movement of the interlocking plate 53 to its extreme left-hand position indicated in dotted lines in Fig. 2. This is the position that the plate 53 occupies when the latch finger 51 has been moved to the releasing position to permit opening of the door 48. It will be noted that while the interlocking plate is in the position shown in Fig. 2, the cam 24 cannot be rotated to close the switchcontacts.
  • the cam 24 occupies the position shown in Fig. 3 and the latch 51 cannot be moved to the open position by reason of the engagement of the finger 57 with the side of the cam wing 25.
  • the switch In order to release the latch to permit opening movement of the door, the switch must first be moved to open position, thus bringing the cam 24 to the position shown in Fig 2, wherein the notch 58 in the cam 24 permits of the necessary movement of the interlocking plate 53 to the left.
  • the apparatus is described as having a spring between the operating handle and the clutch and springs between the switch member and the base, but these are not essential for the reason that the cam and switch may be gravity actuated.
  • a switch comprising a support, a movable contact member mounted thereon and biased toward open position, a rotary cam for engaging the member and moving it to closed position, an operating handle for the cam having a lost motion connection thereto, a spring for yieldingly connecting the operating handle and the said cam, and means on the cam cooperating with the said member for preventing movement of the cam by the said spring until the cam has been positively moved a predetermined distance by the said operating handle.
  • a switch comprising a support, a movable contact member mounted thereon and biased toward open position, a cam cylinder having a pair of cam faces on the end thereof for engaging the contact member and moving it to closed position when the cam is rotated, an operating handle for the cam cylinder having a lost motion connection thereto, a spring for yieldingly connecting the operating handle and the cam cylinder, the said cam surfaces having depressions therein cooperating with the said member for preventin movement of the cam cylinder by the said spring until the cam has been moved a predetermined distance by the operating handle.
  • a switch comprising a support, a movable contact member mounted thereon and biased toward open position and provided with a pair of anti-friction rollers, a cam cylinder having a pair of cam faces on the end thereof for engaging the said rollers and for moving the said member to closed position when the cam is rotated, an operating handle for the cam cylinder having a lost motion connection thereto, a sprin for yieldingly connecting the operating iiandle and the cam cylinder, the said cam surface having depressions therein cooperating with the said rollers for preventing movement of the cam cylinder by the said spring until the cam has been moved a predetermined distance by the operating handle.
  • a switch mechanism comprising a support, a removable cover provided with an opening through which the support projects, an operating handle pivoted on the support, a movable switch member mounted on the support and biased toward open position and an operating cam for the switch member pivoted upon the support and having a lost motion connection to the operating handle, a spring connecting the operating handle and the support for causing the cam to follow the operating handle with a snap action when the cam is released, means for preventing movement of the cam by the spring until the operating handle has moved it a predetermined distance, and an interlocking member on the support cooperating with the cam for preventing opening movement of the cover so long as the switch is in closed position.
  • a switch comprising a support, a movable contact member mounted thereon, a cam for moving the member, an operating handle for the cam having a lost motion connection thereto, a spring for actuating the cam and connecting the handle and the cam, and means for preventing movement of the cam until the operating handle has moved a predetermined distance.
  • a switch comprising a movable contact member normally biased toward open position, a cam for moving the member, an operating handle for the cam having a lost motion connection thereto, a spring for actuating the cam and connecting the handle and the cam, and means for preventing movement of the cam until the operating handle has moved a predetermined distance.
  • a switch comprising a movable contact member normally biased toward open position, a cam for moving the member, an operating handle for the cam having a lost motion connection thereto, and means for biasing the cam toward either of its extreme operating positions.

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  • Push-Button Switches (AREA)

Description

NARROW TYPE PANEL MAIN SWITCH Filed June 8, 1927 3 Sheets-Sheet 1 WITNESSES:
INVENTORS Hubert 11. 16121112 and 1/] 0m Harald G. Barter- O 1929- H. G. BAXTER ET AL 1,730,311
NARROW TYPE PANEL MAIN SWITCH Filed June 1927 3 Sheets-Sheet 2 VII/[III], f 4J 54 WITNESSES: INVENTORS 7. 0 I Hubert If Ifiwnz and Hamid GBaxzcr. BY '7 7ATTONEY O 1, 1929- n. G. IBAXTER ET AL 1,730,311
NARROW TYPE PANEL MAIN SWITCH Patented Oct. 1, 1929 UNITED STATES PATENT OFFICE HAROLD G. BAXTER, OF BALDWIN, AND HUBERT K. KRANTZ, 0F ROCKVILLE CENTER,
NEW YORK, ASSIGNORS T0 WESTINGHOUSE ELECTRIC AND MANUFACTURING COM- PANY, A'CORPORATION OF PENNSYLVANIA NARROW-TYPE PANEL MAIN SWITCH Application filed June 8, 1927.
Our invention relates to switch mechanism and particularly to switch mechanism used for controlling the main circuit of a distributin panel.
One object of our invention is to provide a main switch for a distributing panel that is relatively shallow in depth and does not require a deep panel housing.
Another object of our invention is to provide a switch of the brush type that is moved into closed position by means of a rotary cam and which is opened by a snap action in response to movement of an operating handle.
A further object of our invention is to provide a switch having the above noted characteristics wherein the construction is rugged and wherein relatively great contact pressure can be applied to the switch brushes with little effort, and wherein the contact pres sure is maintained while the switch is in closed position.
These and other objects that will be made apparent throughout the further description of my invention are attained by means of the switch mechanism hereinafter described and illustrated in the accompanying drawings, wherein Figure 1 is a top plan View of a switch embodying features of our invention;
Fig. 2 is a bottom plan view of the switch device shown in Fig. 1 with the operating handle in the off position;
Fig. 3 is a bottom plan View of the switch mechanism showing the position of the operating handle and the cam when the switch is in the on position;
Fig. 4 is a longitudinal section through the switch mechanism taken on the line IV-IV of Fig. 5;
Fig. 5 is a longitudinal section of the switch mechanism taken on the line VV of Fig. 1;
Figs. 6 and 7 are bottom plan and elevational views, respectively, of the operating cam; and
Fig. 8 is a developed view of one of the cams shown in Figs. 6 and 7.
Referring to the drawings, the switch mechanism comprises a base plate 9 that is attached to an insulating base 10 secured to the rear wall 11 of a panel housing. A pair Serial No. 197,388.
of supporting rods 12 are riveted to the base plate and serve to support a cover plate 13 that is spaced from the base plate 9 by means of compression tubes 14, the cover 13 bein securely attached to the rods 12 by means 0% threaded nuts 15.
The switch illustrated is a three-pole switch and is provided with three laminated contact brushes 16 comprising copper strips that are clamped between insulating bars 17 constituting the switch contact carrier, by means of bolts 18. The insulating bars are provided with perforations 19 and slide upon the bushings 14. Springs 21 disposed between the base plate 9 and the bars 17 serve to yieldingly bias the switch brushes and carrier to ward open position as shown in Fig. 5. The brushes 16 are adapted to engage the contact terminals 22 that are mounted on insulating blocks 23 secured to the insulating base 11.
The bushings 14 serve as a guide for the switch contact carrier which is moved inwardly by means of a rotary cam 24 consist ing of two semi-cylindrical cam wings 25 and an end plate 26.
The cam 24 is illustrated in detail in Figs. 6, 7 and 8 and it will be noted that the cam Wings 25 are provided with cam surfaces 27 that are inclined from the end plate 26 and terminate in a slight depression 28, the purpose of which will hereinafter appear.
The cam 24 is pivoted for rotation upon a shaft 29 which is rotatably mounted in the cover plate 13 and is fixed to an operating handle 31. The shaft 29 and the cam 24 are retained in assembled relation by means of a washer 32 that is attached to the inner end of the shaft 29 which is riveted over the washer.
The cover 13 is provided with an arcuate slot 33, Figs. 1, 2 and 3, through which a pin 34 attached to the handle 31 extends. The end plate 26 of the cam is also provided with an arcuate slot 35 through which the pin 34 also extends. By reason of this construction a lost motion connection is provided between the operating handle and the cam, that is, the operating handle may be moved a limited distance without imparting movement to the cam.
The operating handle and the cam are yieldingly connected to one another by means of a spring 36 that is attached at one end to the inner end of the pin 34 and to one of the cam wings 25, the end of the spring being inserted through holes 37 in the cam wing as indicated in Figs. 3 and 4.
Anti-friction rollers 38 are rotatably mounted on pins 39 supported in yoke brackets 41 that are attached to the insulating bars 17 by means of rivets 42. The rollers 38 are aligned with the cam faces or edges of the cam wings 25 and ride over the edges when the cam 24 is rotated.
As indicated in Fig. 5,the brush contact members and the carrier 17 therefor are in open posit-ion and the rollers 38 at this time engage the lowest point of the cams 25. At this time the operating handle occupies the position indicated in Figs. 1 and 2.
Referring to Figs. 2, 3 and 5, the switch is moved to closed position by moving the operating handle 31 from the position shown in Fig. 2 to the position shown in Fig. 3. The pin 34 engages the right-hand end of the slot 35 and rotates the cam wings 25 counterclockwise as in Figs. 2 and 3 with the operating handle. .Rotation of the cam wings 25 causes the rollers 38 to ride on the cam faces and depress the brush contacts into engagement with the contact terminals 22 as shown in Fig. 4. As the cam approaches the end of its travel, the rollers move into depression 28 on the cam faces and serve to retain the cam in the closed position shown in Fig. 4.
Toopen'the switch the operating handle 31 is moved from the on position shown in Fig. 3 to the off position shown in Fig. 2..
By reason of the lost motion connection of the operating handle to the cam 25 and by reason of the rollers 38 being lodged inthe notches or depressions 28, which serve to releasably hold the cam in closed position. the initial movement of the operating handle 31 first stretches the spring 36 which tends to move the cam to the open position. The spring 36, however, does not have suificient tension to overcome the resistance offered by the rollers 38 while in the notches 28, and consequently the cam remains stationary until the pin 34 engages the end 43 of the slot 35 and positively turns the cam in a clockwise direction sufficient distance to cause the rollers 38 to ride over the peaks 44 of the cam faces. After the rollers 38 have passed the high points 44 of the cam, the spring 36 will cause the cam to rotate with a snap motion to the open position shown in Figs. 2 and 5. The compression springs 21 will immediately cause the brush contacts to move to open position with a. snap action. may then be repeated.
By reason of the cam operation of the switch contracts any desired pressure may be obtained between the switch contacts and the contact terminals with little effort ap- The operation plied to the operating handle. The construction is rugged and occupies a minimum of space considering the capacity for which the switch is designed.
It will be understood that the switch is shown as mounted in a panel housing having a bottom wall 11 and a cover or trim 46 having an opening -7 through which the switch cover 13 projects.
Referring to Figure 4 it will .be seen that the panel is provided with a movable door 48 which serves to close an opening over the fuse receptacles (not shown) within the panel housing. Doors of this character are usually provided with a bar latch forretaining the door in closed position, the ends of the bar or bars being movable under the trim adjacent the corners of the, door to lock it in closed position. The latch comprises a bar 49 that is slidably mounted on the inner side of the door'48 and which is provided with an inwardly extending tongue 1 that projects through the notch 52 provided in an interlocking plate 53.
The purpose of the interlocking plate is to prevent opening movement of the latch so long as the switch is in closed position and to prevent closing movement of the switch until the door has been closed and the latch moved to locking position.
The interlocking plate 53 is slidably mounted on the inner side of the switch cover 13 and is secured in position by meansof rivets 54 that extend through slots 55 in the plate 53. The interlocking plate 53 is provided with an extension 56 having a finger 57 that projects toward the inner side of the cover 13 as indicated in Figures 2, 3 and 4.
Referring to Figures 2 and 3, it 'will be seen that the cam 24 is provided with an angular notch 58 which permits movement of the interlocking plate 53 to its extreme left-hand position indicated in dotted lines in Fig. 2. This is the position that the plate 53 occupies when the latch finger 51 has been moved to the releasing position to permit opening of the door 48. It will be noted that while the interlocking plate is in the position shown in Fig. 2, the cam 24 cannot be rotated to close the switchcontacts.
When the switch is in the closed position, the cam 24 occupies the position shown in Fig. 3 and the latch 51 cannot be moved to the open position by reason of the engagement of the finger 57 with the side of the cam wing 25. In order to release the latch to permit opening movement of the door, the switch must first be moved to open position, thus bringing the cam 24 to the position shown in Fig 2, wherein the notch 58 in the cam 24 permits of the necessary movement of the interlocking plate 53 to the left.
By reason of this interlocking mechanism,
access cannot be had to the fuse compart ment while the conductors associated therewith are energized. Consequently, the operation of the device is rendered safe.
The apparatus is described as having a spring between the operating handle and the clutch and springs between the switch member and the base, but these are not essential for the reason that the cam and switch may be gravity actuated.
\Vhile we have illustrated but one embodiment of our inventioinvit will be apparent to those skilled in the art that various changes, modifications, substitutions, additions and omissions may be made in the apparatus illustrated without departing from the spiritand scope of our invention, as set forth in the appended claims.
We claim as our invention:
1. A switch comprising a support, a movable contact member mounted thereon and biased toward open position, a rotary cam for engaging the member and moving it to closed position, an operating handle for the cam having a lost motion connection thereto, a spring for yieldingly connecting the operating handle and the said cam, and means on the cam cooperating with the said member for preventing movement of the cam by the said spring until the cam has been positively moved a predetermined distance by the said operating handle.
2. A switch comprising a support, a movable contact member mounted thereon and biased toward open position, a cam cylinder having a pair of cam faces on the end thereof for engaging the contact member and moving it to closed position when the cam is rotated, an operating handle for the cam cylinder having a lost motion connection thereto, a spring for yieldingly connecting the operating handle and the cam cylinder, the said cam surfaces having depressions therein cooperating with the said member for preventin movement of the cam cylinder by the said spring until the cam has been moved a predetermined distance by the operating handle.
3. A switch comprising a support, a movable contact member mounted thereon and biased toward open position and provided with a pair of anti-friction rollers, a cam cylinder having a pair of cam faces on the end thereof for engaging the said rollers and for moving the said member to closed position when the cam is rotated, an operating handle for the cam cylinder having a lost motion connection thereto, a sprin for yieldingly connecting the operating iiandle and the cam cylinder, the said cam surface having depressions therein cooperating with the said rollers for preventing movement of the cam cylinder by the said spring until the cam has been moved a predetermined distance by the operating handle.
4. A switch mechanism comprising a support, a removable cover provided with an opening through which the support projects, an operating handle pivoted on the support, a movable switch member mounted on the support and biased toward open position and an operating cam for the switch member pivoted upon the support and having a lost motion connection to the operating handle, a spring connecting the operating handle and the support for causing the cam to follow the operating handle with a snap action when the cam is released, means for preventing movement of the cam by the spring until the operating handle has moved it a predetermined distance, and an interlocking member on the support cooperating with the cam for preventing opening movement of the cover so long as the switch is in closed position.
5. A switch comprising a support, a movable contact member mounted thereon, a cam for moving the member, an operating handle for the cam having a lost motion connection thereto, a spring for actuating the cam and connecting the handle and the cam, and means for preventing movement of the cam until the operating handle has moved a predetermined distance.
6. A switch comprising a movable contact member normally biased toward open position, a cam for moving the member, an operating handle for the cam having a lost motion connection thereto, a spring for actuating the cam and connecting the handle and the cam, and means for preventing movement of the cam until the operating handle has moved a predetermined distance.
7. A switch comprising a movable contact member normally biased toward open position, a cam for moving the member, an operating handle for the cam having a lost motion connection thereto, and means for biasing the cam toward either of its extreme operating positions.
In testimony whereof, we have hereunto subscribed our names this 28th day of May,
HAROLD G. BAXTER. HUBERT K. KRANTZ.
US197388A 1927-06-08 1927-06-08 Narrow-type panel main switch Expired - Lifetime US1730311A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5963420A (en) * 1997-09-22 1999-10-05 Eaton Corporation Interlock bypass

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5963420A (en) * 1997-09-22 1999-10-05 Eaton Corporation Interlock bypass

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