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US2840651A - Rotary drum limit switch operating mechanism - Google Patents

Rotary drum limit switch operating mechanism Download PDF

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Publication number
US2840651A
US2840651A US642214A US64221457A US2840651A US 2840651 A US2840651 A US 2840651A US 642214 A US642214 A US 642214A US 64221457 A US64221457 A US 64221457A US 2840651 A US2840651 A US 2840651A
Authority
US
United States
Prior art keywords
cam
drum
limit switch
units
circumferential
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US642214A
Other languages
English (en)
Inventor
Walter P Weglarz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ThyssenKrupp Budd Co
Original Assignee
Budd Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Budd Co filed Critical Budd Co
Priority to US642214A priority Critical patent/US2840651A/en
Priority to DEB47893A priority patent/DE1186129B/de
Application granted granted Critical
Publication of US2840651A publication Critical patent/US2840651A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H19/00—Switches 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
    • H01H19/54—Switches 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
    • H01H19/60—Angularly-movable actuating part carrying no contacts
    • H01H19/62—Contacts actuated by radial cams
    • H01H19/623—Adjustable cams
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H43/00—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed
    • H01H43/10—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed with timing of actuation of contacts due to a part rotating at substantially constant speed
    • H01H43/12—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed with timing of actuation of contacts due to a part rotating at substantially constant speed stopping automatically after a single cycle of operation
    • H01H43/121—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed with timing of actuation of contacts due to a part rotating at substantially constant speed stopping automatically after a single cycle of operation using a drum

Definitions

  • This invention relates to rotary drum limit switch operating mechanism and has for an object the provision of improvements in this art.
  • the invention has been developed in connection with limit switch operating mechanism for metal forming presses and will be discussed in this connection though without intention of limiting the eld of use of the invention in any way.
  • limit switch control mechanisms for accurately controlling the actions of .various parts of the press as well as various related devices such as feeders and ejectors (broadly referred to as servers) which must operate in accurately timed relationship with the press.
  • These limit switch control mechanisms generally comprise a group of adjustable cams carried on a rotary cam shaft and a corresponding group of limit switches carried ⁇ by a casing or shell surrounding the cams and operated 'by the cams.
  • the limit switches are mounted at an interior location and an outside rotary drum carries all of the cams for operating the limit switches.
  • the mechanism is so designed that all cam setings and adjustments can -be made from the outside of the drum and consequently there is no danger of exposure to live contacts. Neither is there any need to manipulate any parts related to an electrical circuit. Therefore there is no need to have an electrician on the job when setting up operations.
  • Another benefit of the arrangement is that the enclosed mechanism permits with safety the use of switches of heavy current capacity so that it is lnot necessary to use low current limit switches which act through high current relays, as is required when con tacts are exposed during adjustment.
  • the apparatus includes means for installing parts to give an unlimited selection of cam action by inserting or rearranging or removing standard parts.
  • the apparatus also includes means for obtaining a vernier or micrometer adjustment of the end of the cam and this independently for either end.
  • the apparatus also provides clearly visible scales which indicate the selected cam arrangement so this can be noted and recorded for future reference, as for example for a later rapid resetting to perform the same operations.
  • the apparatus also provides means for making all cam settings and adjustments wholly by manipulation of parts which are provided and without the use of any Y tools whatever.
  • Fig. l is a vertical axial section through one form of ⁇ apparatus embodying the invention.
  • Fig. 2 is a vertical transverse section taken on the line 22 of Fig. l;
  • Fig. 3 is a flat developed plan View ofthe outer surface of the rotary drum, some of the cam element units lbeing shown in section, to show what the action will be in one complete rotation of the drum;
  • Fig. 4 is an enlarged partial transverse vertical section showing a cam having a Vernier adjustment at one end, the view being taken on the line 4-4 of Fig. 5;
  • Fig. 5 is a partial flat projection of the parts shown in Fig. 4 as seen from the line 5-5 on Fig. 4;
  • Fig. 6 is a perspective View of the apparatus with a protective outer cover in place, parts of the outer cover being cut away to show the rotary drum within;
  • Fig. 7 is a transverse section in perspective, the section being indicated by the line 7-7 in Fig. 1.
  • the apparatus comprises a base 1i) which is adapted to be mounted in any convenient position, as on a press for example.
  • the base carries a pedestal support 11 on which there issecured, as by cap bolts 12, an insulating support bar 13 on which there are mounted a plurality of limit switch units 14.
  • each limit switch comprises a pair of fixed contacts 15 and 16 and a closure member 17 which is pivotally ,mounted on a shaft 18 carried by a support 19 on the insulating support bar 13.
  • the pivoted closure member has an extension carrying an operating roller 20 adapted to 'be operated by a rotary cam.
  • Conductor leads 21 extend from the contacts 15, 15 into a conduit 2.2 secured in the Ypedestal support 11 whence they run to their appropriate connections.
  • the closure member 17 is urged toward contact engaging or circuit closing position by a spring 23.
  • a pedestal support 26 which carries a bearing v2'1' in which a driven drum shaft 28 is rotatably mounted.
  • the shaft carries a head 29 which comprises part of a rotary cam drum 3i).
  • a sealing and friction-reducing ring 32 for rigidity the end of the drum isrotatably supported on an annular bearing ange 31 carried by the pedestal support 11, a sealing and friction-reducing ring 32, as of nylon or Teflon being interposed 'between the flange 31 and the inner surface of the drum.
  • the insulating bar 13 has abearing cup 33 secured thereon, as vby cap bolts 34, and within this bearing cup there is rotatably mounted a hub 3'5 of the ead 29, a sealing and friction reducing ring 36 as of nylon or Teon being interposed.
  • the drum in a plurality of axial positions corresponding to the limit switch positions is provided with a plurality of circumferential slots 4t) separated by bars 41 of the drum providing for the arrangement of operating cams over any part or all of the complete circumference.
  • the screws are adapted to secure L-shaped cam sector units 45 to the drum.
  • the lower portion of a cam sector unit is bent7 as at 45a, to present a widened surface to the switch cam roller 2' but there is suflicient Width in the slot for two of the bent portions 45a to enter side by side.
  • the cam roller is made ofdielectric material or is insulated.
  • the screw holes 42 on opposite sides of a slot are staggered relative to each other so that the cam units can have an overlap to obtain a total length of cam operating surface which is other than a multipleof the cam sector units.
  • the screw holes 42 are placed l0 defr grees apart so that the full circumference is divided into 36 equal spaces and there is a 5 degree offset between the holes of adjacent rows.
  • the cam segments shown herein have an extent of 2O degrees and by an end overlap a length range from l5 degrees down to 5 degrees can be obtained. It will be observed that the cam units are cut away on the ends, as at 45h, so as to meet at thc connecting bars 41. While the cam units selected for illustration herein have a circumferential length of 2() degrees, they could be either longer or shorter but preferably are some multiple of the screw hole spacing.
  • a more precise length adjustment means are hereby provided for moving the end cam sector unit with a micrometer or Vernier control.
  • This arrangement is shown in Figs. 4 and 5.
  • the sector in the top arm which is clamped to the drum is provided with a circumferential slot 45C to receive the clamp screw 42.
  • an upturned projection 45d is apertured or slotted from the end to receive a grooved head 48 of a Vernier adjusting screw 49 threaded in a short shaft 56 turnably carried in the upturned ears of an anchor screw 5l threaded in one of the holes 42.
  • a knurled head 52 is threaded on the adjusting screw 49 after it has been screwed in the short shaft 50 and is secured thereon by a drive pin 53. It will be seen that the grooved head can be entered in the slot of the upturned portion 45d after the anchor screw has been screwed into the drum. If the Vernier arrangement is not desired the slotted cam segment can be moved by hand and clamped by the screw 43.
  • the drum 30 is provided with a marked scale 55 at one or more points as desired to provide a reading of the cam arrangements. This may be read and recorded for future reference.
  • the entire apparatus is enclosed by a dust proof cover 56 which is removed while making adjustments. and replaced to protect the operating apparatus after the adjustments have been made.
  • Rotary limit switch operating apparatus comprising in combination, a xed inner support, a limit switch mounted on said support and provided with a cam follower adapted to be operated by a circumferentially moving cam, a cam drum mounted for rotation around said switch and its cam follower, said drum being provided with circumferentially elongated slots separated by short connecting elements, a plurality of cam units, each having a circumferentially extending cam segmentdisposed in a circumferential slot and a part lying outside the drum, a plurality of circumferential cam segments Vtogether forming a circumferential composite cam for actuating said cam follower, and means securing the cam units by their outside elements to the drum.
  • Rotary limit switchV operating apparatus comprising in combination, a fixed inner support, a limit switch mounted on said support and provided with a cam follower adapted to be operated by a circumferentially moving cam, a cam drum mounted for rotation around said switch and its cam follower, said drum being provided with circumferentially elongated slots separated by short connecting elements, a plurality of cam units, each having a circumferentially extending cam segment disposed -in a circumferential slot and a part lying outside the drum, a plurality of circumferential cam segments together forming a circumferential composite cam for actuating said cam follower, and means securing the cam units by their outside elements to the drum, said composite cam comprising some segments which overlap each other circumferentially to provide a total circumferential cam length which is other than a multiple of the total lengths of the cam segments of which it is composed.
  • Rotary limit switch operating apparatus comprising in combination, a fixed inner support, a limit switch mounted on said support and provided with a cam follower adapted to be operated by a circumferentially moving cam, a cam drum mounted for rotation around said switch and its cam follower, said drum being provided with circumferentially elongated slots separated by short connecting elements, a plurality of cam units, each having a circumferentially extending cam segment disposed in a circumferential slot and a part lying outside the drum, a plurality of circumferential cam segments together forming a circumferential composite cam for actuating said cam follower, and means securing the cam units by their outside elements to the drum, said cam units being L-shaped with a first arm of the L being blade-shaped to enter a slot from outside and with the second arm lying over the outer surface of the drum alongside the slot, and means for securing said second arms of said cam units to the drum.
  • Rotary limit switch operating apparatus comprising in combination, a fixed inner support, a limit switch mounted on said support and provided with a cam follower ⁇ adapted to be operated by a circumferentially moving cam, a cam drum mounted for rotation around said switch and its cam follower, said drum being provided with circumferentially elongated slots separated by short connecting elements, a plurality of cam units, each having a circumferentially extending cam segment disposed in a circumferential slot and a part lying outside the drum, a plurality of circumferential cam segments together forming a circumferential composite cam for actuating said cam follower, and means securing the cam units by their outside elements to the drum, said cam units being l-- shaped with a lirst arm of the L being blade-shaped to enter a slot from outside and with the Second arm lying over the outer surface of the drumY alongside the slot, and means for securing said second arms of said cam units to the drum, the means for securing said second arms of the cam units to the drum comprising
  • Rotary limit switch operating apparatus comprising in combination, a fixed inner support, a limit switch mounted on said support and provided with a cam follower adapted to be operated by a circumferentially moving cam, a cam drum mounted fory rotation around said switch and its cam follower, said drum being provided Vwith circumferentially elongated slots separated by short connecting elements, a plurality of cam units, each having a circumferentially extending cam segment disposed in a circumferential slot and a part lying outside the drum, a plurality of circumferential cam segments together forming a circumferential composite cam for actuating said cam follower, and means securing the cam units by their outside elements to the drum, said cam units being L- shaped with a first arm of the L being blade-shaped to enter a slot from outside and with the second arm lying over the outer surface of the drum alongside the slot, and means for securing said second arms of said cam units to the drum, at least some of the cam units being provided with circumferentially elongated slots in their second arms which
  • Rotary drum limit switch operating apparatus comprising in combination, a pedestal support, a support bar carrying a limit switch carried by said pedestal support, a second pedestal support spaced axially from the first said pedestal support, a rotary drum having a shaft rotat- 6 ably carried by said second support, adjustable cam operators carried by said drum which are insertable and adjustable from the outside, and rotary bearings between the outer end of the drum and the first pedestal support and between the outer end of the support bar and the second pedestal support.

Landscapes

  • Gear-Shifting Mechanisms (AREA)
  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
US642214A 1957-02-25 1957-02-25 Rotary drum limit switch operating mechanism Expired - Lifetime US2840651A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US642214A US2840651A (en) 1957-02-25 1957-02-25 Rotary drum limit switch operating mechanism
DEB47893A DE1186129B (de) 1957-02-25 1958-02-18 Nockenwalzenschalter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US642214A US2840651A (en) 1957-02-25 1957-02-25 Rotary drum limit switch operating mechanism

Publications (1)

Publication Number Publication Date
US2840651A true US2840651A (en) 1958-06-24

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Family Applications (1)

Application Number Title Priority Date Filing Date
US642214A Expired - Lifetime US2840651A (en) 1957-02-25 1957-02-25 Rotary drum limit switch operating mechanism

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US (1) US2840651A (de)
DE (1) DE1186129B (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2920152A (en) * 1957-09-06 1960-01-05 Harry C Werner Time limit switch
US2952750A (en) * 1958-07-11 1960-09-13 Mason Electric Corp Motor driven rotary switch
DE1640341B1 (de) * 1966-09-10 1971-06-09 Eduard Hermle Elektrisches nockenschaltwerk
US20060224275A1 (en) * 2002-07-11 2006-10-05 Magnus Heldesjo Device for an industrial robot

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2692534A (en) * 1952-03-06 1954-10-26 Sperry Corp Gunfire cutoff device

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB277606A (de) * 1900-01-01
DE921524C (de) * 1943-11-20 1954-12-20 Paul Firchow Nachfgr App U Uhr Nockenschalteinrichtung nach Art eines Walzenschalters
US2484152A (en) * 1945-02-02 1949-10-11 David A Bruton Radio time switch
US2753405A (en) * 1953-06-30 1956-07-03 Danly Mach Specialties Inc Rotary limit switch assembly

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2692534A (en) * 1952-03-06 1954-10-26 Sperry Corp Gunfire cutoff device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2920152A (en) * 1957-09-06 1960-01-05 Harry C Werner Time limit switch
US2952750A (en) * 1958-07-11 1960-09-13 Mason Electric Corp Motor driven rotary switch
DE1640341B1 (de) * 1966-09-10 1971-06-09 Eduard Hermle Elektrisches nockenschaltwerk
US20060224275A1 (en) * 2002-07-11 2006-10-05 Magnus Heldesjo Device for an industrial robot

Also Published As

Publication number Publication date
DE1186129B (de) 1965-01-28

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