US3397650A - Braking device for power and free conveyor carriers - Google Patents

Braking device for power and free conveyor carriers Download PDF

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Publication number
US3397650A
US3397650A US588959A US58895966A US3397650A US 3397650 A US3397650 A US 3397650A US 588959 A US588959 A US 588959A US 58895966 A US58895966 A US 58895966A US 3397650 A US3397650 A US 3397650A
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Prior art keywords
carrier
dog
driving
releasing member
actuating member
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Expired - Lifetime
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US588959A
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Kondur Louis
Clarence A Dehne
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Jervis B Webb Co
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Jervis B Webb Co
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Priority to US588959A priority Critical patent/US3397650A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61BRAILWAY SYSTEMS; EQUIPMENT THEREFOR NOT OTHERWISE PROVIDED FOR
    • B61B10/00Power and free systems
    • B61B10/02Power and free systems with suspended vehicles
    • B61B10/025Coupling and uncoupling means between power track abd vehicles

Definitions

  • This invention relates to a device for braking forward and rebounding movement of a power and free conveyor carrier having a releasable driving dog when the carrier overtakes a preceding stopped carrier.
  • Conveyor carriers of the type to which the invention is applicable are movable along a supporting track by a pusher on a driven chain engaging a driving dog on the carrier, the driving dog being movable from a driving to a non-driving position in response to engagement of a dog releasing member on the front of the carrier with an actuating member on the rear of a preceding overtaken carrier.
  • a carrier construction is disclosed in US. Patent 3,044,416.
  • the object of the present invention is to provide a braking device operable to retard forwarding and rebounding movement of an overtaking carrier thereby reducing the impact and the rebounding motion which may be caused by a given amount of impact.
  • a further object is to provide a braking device which can be combined with and operated by the dog releasing mechanism.
  • the invention provides brake means carried by the dog releasing member on the front of a carrier, and a cam surface on an actuating member at the rear of a preceding overtaken carrier adapted to move the dog releasing member to released position and the brake means into frictional contact with the carrier supporting track.
  • the brake means consists of a brake shoe mounted on a resilient pad; and, in accor'dance with another preferred feature, a positioning member is provided on the front of a carrier to co-act with a second cam surface on the actuating member of the preceding carrier, the second cam surface having a portion engageable by the positioning member subsequent to engagement of the first cam surface by the dog releasing member for augmenting movement of the brake means into firm contact with the supporting track.
  • FIGURE 1 is a side elevation showing the rear portion of a leading carrier and the front portion of an immediately following carrier, the following carrier being stopped by the dog releasing mechanism and braking device;
  • FIGURE 2 is an enlarged sectional elevation taken as indicated by the line 22 of FIG. 1.
  • a carrier is movable along a supporting track 12 formed by a pair of channel members 13 and 14, by a pusher 16 on a chain 18 engaging a driving dog 20 on the carrier.
  • the chain .18 is driven by conventional means (not shown) in the direction of the arrow 22, and the driving dog 20 is movable between the driving position shown in broken line and the non-driving position shown in full line in response to engagement of a dog releasing member 24 on the front of the carrier 3,397,650 Patented Aug. 20, 1968 10 with an actuating member 26 mounted on the rear of a preceding carrier 28.
  • the dog releasing member 24 is connected to the body of the carrier 10 by a pivot 30 and to the lower portion of the driving dog 20 by a pin 31.
  • Brake means 32 is secured to the forward upper portion of the dog releasing member 24, and consists of a brake shoe 34, a mounting plate 35 fastened to the member 24 by screws 36 and a resilient pad 38 interposed between the brake shoe 34 and mounting plate 35 and to which these parts are bonded.
  • the actuating member 26 on the rear of the preceding carrier 28 is provided with-an upper cam surface 40 and a lower cam surface 42.
  • the forward end of the dog releasing member 24 engages the upwardly sloping portion 43 of the cam surface 40 on the actuating member, resulting in movement of the driving dog 20 of the carrier 10 from driving to non-driving position.
  • the upper cam surface 40 is also adapted to move the dog releasing lever sufficiently to bring the brake shoe 34 into contact with the lower surfaces 44 of the carrier supporting track members 13 and 14, and this braking action is maintained by the horizontal portion 46 of the upper cam surface on the actuating member 26.
  • the lower cam surface 42 of the actuating member is engageable by a positioning member 48 which is integral with or rigidly secured to the body of the carrier 10 and projects forwardly thereof in vertically spaced relation to the dog releasing member 24.
  • a follower portion 50 near the leading end of the positioning member 48 may initially engage the first horizontal part 51 of the lower cam surface 42 to insure proper vertical alignment between the actuating member and dog releasing member.
  • the lower cam surface 42 is also provided with an offset portion 52 adapted, when engaged by the positioning member 48, to augment the movement of the dog releasing member 24 to a braking position and urge the brake means into firm frictional contact with the carrier supporting track.
  • This offset portion 52 is arranged so as to be engaged by the follower 50 on the positioning member 48 subsequent to movement of the dog releasing member and driving dog to a non-driving or released position so that braking action will be augmented after the driving dog 20 has been disengaged from the moving pusher 16.
  • the action of the lower cam surface is preferably aided by mounting the actuating member 26 movably on the body of the carrier 28. In the construction shown this is accomplished by a pair of pins 54 on the trolley body engaging slots 56 in the tongue portion 58 of the actuating member which extends between vertical side walls of the carrier body.
  • a conveyor carrier of the type which is propelled along a supporting track by a pusher on a driven chain engaging a driving dog on the carrier, the driving dog be ing movable from a driving to a non-driving position in response to movement of a dog releasing member on the front of the carrier resulting from engagement of the dog releasing member with an actuating member on the rear of a preceding overtaken carrier, characterized by brake means carried by the dog releasing member, the actuating member having cam means adapted to move the dog releasing member to a released position and the brake means into frictional contact with the carrier supporting track.
  • a conveyor carrier as claimed in claim 1 wherein the brake means comprises a mounting plate secured to the dog releasing member, a brake shoe, and a resilient pad interposed between the brake shoe and the mounting plate.
  • cam means includes means for urging the actuating member toward the carrier supporting track subsequent to movement of the dog releasing member toward released position to augment movement of the brake means into frictional engagement with the carrier supporting track.
  • a conveyor carrier as claimed in claim 4 wherein the brake means comprises a brake shoe and a resilient pad supporting the brake shoe.
  • a conveyor carrier as claimed in claim .1 further characterized by a positioning member mounted on the front of the carrier in spaced relation 'with the dog releasing member, the actuating member on the rear of the overtaken carrier having first and second cam surfaces, the second cam surface including a portion engageable by the positioning member subsequent to engagement of the first cam surface by the dog releasing member for urging the brake means into contact with the carrier supporting track.
  • a conveyor carrier as claimed in claim 1 further characterized by a positioning member mounted on the front of the carrier in vertically spaced relation below the dog releasing member, the actuating member on the rear of the overtaken carrier having upper and lower cam surfaces of which the upper cam surface is engageable by the dog releasing member, the lower cam surface including a portion engageable by the positioning member subsequent to engagement of the upper cam surface by the dog releasing member for urging the brake means into frictional contact with the supporting track and the upper cam surface of the actuating member into increased frictional engagement with the dog releasing member.
  • a conveyor carrier as claimed in claim 10 further characterized by means mounting the actuating member on the rear of the overtaken carrier for movement toward the carrier supporting track in response to engagement of the lower cam surface of the actuating member by the positioning member.
  • a conveyor carrier as claimed in claim 11 wherein the means mounting the actuating member comprises pin and slot connections defining a direction of movement of the actuating member substantially normal to the carrier supporting track.

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Escalators And Moving Walkways (AREA)

Description

8- 20, 1958 1.. KONDUR ETAL 3,397,650
BRAKING DEVICE FOR POWER AND FREE CONVEYOR CARRIERS Filed Oct. 24, 1966 M 4 3 3 P 4 Q 4 l a J I U 2 FM. Fla F m F 5 m fl m T M m WW 4 United States Patent 3,397,650 BRAKING DEVICE FOR POWER AND FREE CONVEYOR CARRIERS Louis Kondur, Birmingham, and Clarence A. Dehne,
Orchard Lake, Mich., assignors to Jervis B. Webb Company, a corporation of Michigan Filed Oct. 24, 1966, Ser. No. 588,959 12 Claims. (Cl. 104-172) This invention relates to a device for braking forward and rebounding movement of a power and free conveyor carrier having a releasable driving dog when the carrier overtakes a preceding stopped carrier.
Conveyor carriers of the type to which the invention is applicable are movable along a supporting track by a pusher on a driven chain engaging a driving dog on the carrier, the driving dog being movable from a driving to a non-driving position in response to engagement of a dog releasing member on the front of the carrier with an actuating member on the rear of a preceding overtaken carrier. Such a carrier construction is disclosed in US. Patent 3,044,416.
When a driven carrier of this type overtakes a preceding stopped carrier, the resulting impact can be sufiicient to impose a limitation upon the rate at which carriers can be driven, and can also cause objectionable rebounding movement of the overtaking carrier. The object of the present invention is to provide a braking device operable to retard forwarding and rebounding movement of an overtaking carrier thereby reducing the impact and the rebounding motion which may be caused by a given amount of impact. A further object is to provide a braking device which can be combined with and operated by the dog releasing mechanism.
The invention provides brake means carried by the dog releasing member on the front of a carrier, and a cam surface on an actuating member at the rear of a preceding overtaken carrier adapted to move the dog releasing member to released position and the brake means into frictional contact with the carrier supporting track. Preferably the brake means consists of a brake shoe mounted on a resilient pad; and, in accor'dance with another preferred feature, a positioning member is provided on the front of a carrier to co-act with a second cam surface on the actuating member of the preceding carrier, the second cam surface having a portion engageable by the positioning member subsequent to engagement of the first cam surface by the dog releasing member for augmenting movement of the brake means into firm contact with the supporting track.
Other features and advantages of the invention will appear from the following description of the construction shown in the accompanying drawings in which:
FIGURE 1 is a side elevation showing the rear portion of a leading carrier and the front portion of an immediately following carrier, the following carrier being stopped by the dog releasing mechanism and braking device; and
FIGURE 2 is an enlarged sectional elevation taken as indicated by the line 22 of FIG. 1.
The construction shown illustrates the application of the invention to carriers equipped with driving dog releasing mechanism of the type disclosed in the above mentioned US. patent. A carrier is movable along a supporting track 12 formed by a pair of channel members 13 and 14, by a pusher 16 on a chain 18 engaging a driving dog 20 on the carrier. The chain .18 is driven by conventional means (not shown) in the direction of the arrow 22, and the driving dog 20 is movable between the driving position shown in broken line and the non-driving position shown in full line in response to engagement of a dog releasing member 24 on the front of the carrier 3,397,650 Patented Aug. 20, 1968 10 with an actuating member 26 mounted on the rear of a preceding carrier 28. The dog releasing member 24 is connected to the body of the carrier 10 by a pivot 30 and to the lower portion of the driving dog 20 by a pin 31.
Brake means 32 is secured to the forward upper portion of the dog releasing member 24, and consists of a brake shoe 34, a mounting plate 35 fastened to the member 24 by screws 36 and a resilient pad 38 interposed between the brake shoe 34 and mounting plate 35 and to which these parts are bonded.
The actuating member 26 on the rear of the preceding carrier 28 is provided with-an upper cam surface 40 and a lower cam surface 42.
Assuming the carrier 28 is stopped and is being overtaken by the carrier 10, the forward end of the dog releasing member 24 engages the upwardly sloping portion 43 of the cam surface 40 on the actuating member, resulting in movement of the driving dog 20 of the carrier 10 from driving to non-driving position. The upper cam surface 40 is also adapted to move the dog releasing lever sufficiently to bring the brake shoe 34 into contact with the lower surfaces 44 of the carrier supporting track members 13 and 14, and this braking action is maintained by the horizontal portion 46 of the upper cam surface on the actuating member 26.
The lower cam surface 42 of the actuating member is engageable by a positioning member 48 which is integral with or rigidly secured to the body of the carrier 10 and projects forwardly thereof in vertically spaced relation to the dog releasing member 24. A follower portion 50 near the leading end of the positioning member 48 may initially engage the first horizontal part 51 of the lower cam surface 42 to insure proper vertical alignment between the actuating member and dog releasing member. The lower cam surface 42 is also provided with an offset portion 52 adapted, when engaged by the positioning member 48, to augment the movement of the dog releasing member 24 to a braking position and urge the brake means into firm frictional contact with the carrier supporting track. This offset portion 52 is arranged so as to be engaged by the follower 50 on the positioning member 48 subsequent to movement of the dog releasing member and driving dog to a non-driving or released position so that braking action will be augmented after the driving dog 20 has been disengaged from the moving pusher 16. The action of the lower cam surface is preferably aided by mounting the actuating member 26 movably on the body of the carrier 28. In the construction shown this is accomplished by a pair of pins 54 on the trolley body engaging slots 56 in the tongue portion 58 of the actuating member which extends between vertical side walls of the carrier body.
Forward motion of the overtaking carrier 10 is arrested by abutment between the leading end 60 of the positioning member 48 with a shoulder on the actuating member 26 which takes place after full braking action has been obtained from the cam surfaces 40 and 42 of the actuating member, and this full braking action includes increased frictional engagement between the dog releasing member 24 and portion 46 of the upper cam surface 40 of the actuating member, resulting from the augmenting action of the lower cam surface 42 and the resilient pad 38 for mounting the brake shoe 34. Full braking action is obtained prior to the time forward motion of the overtaking carrier 10 is stopped, and full braking action is maintained to resist any rebounding movement. Braking action is self-releasing, as the brake means 32 increases the counterweight action of the forward portion of the dog releasing member 24 to return the dog releasing member and driving dog of the carrier 10 to normal or driving position when the carrier 28 moves on.
While preferred embodiments have been described above in detail, it will be understood that numerous modifications might be restored to without departing from the scope of the invention as defined in the following claims.
We claim:
1. A conveyor carrier of the type which is propelled along a supporting track by a pusher on a driven chain engaging a driving dog on the carrier, the driving dog be ing movable from a driving to a non-driving position in response to movement of a dog releasing member on the front of the carrier resulting from engagement of the dog releasing member with an actuating member on the rear of a preceding overtaken carrier, characterized by brake means carried by the dog releasing member, the actuating member having cam means adapted to move the dog releasing member to a released position and the brake means into frictional contact with the carrier supporting track.
2. A conveyor carrier as claimed in claim 1 wherein the brake means comprises a brake shoe and a resilient pad supporting the brake shoe.
3. A conveyor carrier as claimed in claim 1 wherein the brake means comprises a mounting plate secured to the dog releasing member, a brake shoe, and a resilient pad interposed between the brake shoe and the mounting plate.
4. A conveyor carrier as claimed in claim 1 wherein the cam means includes means for urging the actuating member toward the carrier supporting track subsequent to movement of the dog releasing member toward released position to augment movement of the brake means into frictional engagement with the carrier supporting track.
5. A conveyor carrier as claimed in claim 4 wherein the actuating member is mounted for movement toward the carrier supporting track.
6. A conveyor carrier as claimed in claim 4 wherein the brake means comprises a brake shoe and a resilient pad supporting the brake shoe.
7. A conveyor carrier as claimed in claim .1 further characterized by a positioning member mounted on the front of the carrier in spaced relation 'with the dog releasing member, the actuating member on the rear of the overtaken carrier having first and second cam surfaces, the second cam surface including a portion engageable by the positioning member subsequent to engagement of the first cam surface by the dog releasing member for urging the brake means into contact with the carrier supporting track.
8. A conveyor carrier as claimed in claim 7 wherein the actuating member is mounted for movement toward the carrier supporting track in response to engagement of the second cam surface thereof by the positioning member.
9. A conveyor carrier as claimed in claim 1 further characterized by a positioning member mounted on the front of the carrier in vertically spaced relation below the dog releasing member, the actuating member on the rear of the overtaken carrier having upper and lower cam surfaces of which the upper cam surface is engageable by the dog releasing member, the lower cam surface including a portion engageable by the positioning member subsequent to engagement of the upper cam surface by the dog releasing member for urging the brake means into frictional contact with the supporting track and the upper cam surface of the actuating member into increased frictional engagement with the dog releasing member.
10. A conveyor carrier as claimed in claim 9 wherein the brake means comprises a brake shoe and a resilient pad supporting the brake shoe.
11. A conveyor carrier as claimed in claim 10 further characterized by means mounting the actuating member on the rear of the overtaken carrier for movement toward the carrier supporting track in response to engagement of the lower cam surface of the actuating member by the positioning member.
12. A conveyor carrier as claimed in claim 11 wherein the means mounting the actuating member comprises pin and slot connections defining a direction of movement of the actuating member substantially normal to the carrier supporting track.
References Cited UNITED STATES PATENTS 2/1962 Perkins 104178 X 4/1967 Potter l04172 X

Claims (1)

1. A CONVEYOR CARRIER OF THE TYPE WHICH IS PROPELLED ALONG A SUPPORTING TRACK BY A PUSHER ON A DRIVEN CHAIN ENGAGING A DRIVING DOG ON THE CARRIER, THE DRIVING DOG BEING MOVABLE FROM A DRIVING TO A NON-DRIVING POSITION IN RESPONSE TO MOVEMENT OF A DOG RELEASING MEMBER ON THE FRONT OF THE CARRIER RESULTING FROM ENGAGMENT OF THE DOG RELEASING MEMBER WITH AN ACTUATING MEMBER ON THE REAR OF A PRECEDING OVERTAKEN CARRIER, CHARACTERIZED BY BRAKE MEANS CARRIED BY THE DOG RELEASING MEMBER, THE ACTUATING MEMBER HAVING CAM MEANS ADAPTED TO MOVE THE DOG RELEASING MEMBER TO A RELEASED POSITION AND THE BRAKE MEANS INTO FRICTIONAL CONTACT WITH THE CARRIER SUPPORTING TRACK.
US588959A 1966-10-24 1966-10-24 Braking device for power and free conveyor carriers Expired - Lifetime US3397650A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4143599A (en) * 1977-09-27 1979-03-13 A-T-O Inc. Power and free trolley apparatus
DE3213779A1 (en) * 1982-04-08 1983-10-20 Louis Schierholz Kg, 2800 Bremen Rail-guided travelling gear for power-and-free system
US4593624A (en) * 1985-02-11 1986-06-10 Planet Corporation Power and free conveyor
US5067414A (en) * 1990-02-12 1991-11-26 Mid-West Conveyor Company, Inc. Self-adjusting shock absorbing carrier
US5320211A (en) * 1992-06-04 1994-06-14 Tsubakimoto Chain Co. Backstop device of carrier in trolley conveyor
US5511487A (en) * 1994-04-14 1996-04-30 Daifuku Co., Ltd. Transport system with electric movers
US5524548A (en) * 1995-02-09 1996-06-11 Fox; Richard D. Festoon brake system
US20110072580A1 (en) * 2009-09-28 2011-03-31 Karl Imhoff Locking Safety Mechanism for Suspended Transport Apparatus
US20150238786A1 (en) * 2009-07-10 2015-08-27 Transol Corporation Anchor trolley and fall arrest system and method implementing the same

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3020855A (en) * 1959-07-29 1962-02-13 Mechanical Handling Sys Inc Conveyor stop, release and advance mechanism
US3314378A (en) * 1962-07-02 1967-04-18 Midwest Conveyor Company Inc Drive disengaging trolley system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3020855A (en) * 1959-07-29 1962-02-13 Mechanical Handling Sys Inc Conveyor stop, release and advance mechanism
US3314378A (en) * 1962-07-02 1967-04-18 Midwest Conveyor Company Inc Drive disengaging trolley system

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4143599A (en) * 1977-09-27 1979-03-13 A-T-O Inc. Power and free trolley apparatus
DE3213779A1 (en) * 1982-04-08 1983-10-20 Louis Schierholz Kg, 2800 Bremen Rail-guided travelling gear for power-and-free system
US4593624A (en) * 1985-02-11 1986-06-10 Planet Corporation Power and free conveyor
US5067414A (en) * 1990-02-12 1991-11-26 Mid-West Conveyor Company, Inc. Self-adjusting shock absorbing carrier
US5320211A (en) * 1992-06-04 1994-06-14 Tsubakimoto Chain Co. Backstop device of carrier in trolley conveyor
US5511487A (en) * 1994-04-14 1996-04-30 Daifuku Co., Ltd. Transport system with electric movers
US5524548A (en) * 1995-02-09 1996-06-11 Fox; Richard D. Festoon brake system
US20150238786A1 (en) * 2009-07-10 2015-08-27 Transol Corporation Anchor trolley and fall arrest system and method implementing the same
US10617897B2 (en) 2009-07-10 2020-04-14 Transol Coporation Anchor trolley and fall arrest system and method implementing the same
US9901759B2 (en) * 2009-07-10 2018-02-27 Transol Corporation Anchor trolley and fall arrest system and method implementing the same
WO2011037608A1 (en) * 2009-09-28 2011-03-31 Karl Imhoff Locking safety mechanism for suspended transport apparatus
US8650675B2 (en) 2009-09-28 2014-02-18 Karl Imhoff Locking safety mechanism for suspended transport apparatus
GB2488263B (en) * 2009-09-28 2014-03-19 Karl Imhoff Locking safety mechanism for suspended transport apparatus
US8296878B2 (en) 2009-09-28 2012-10-30 Karl Imhoff Locking safety mechanism for suspended transport apparatus
GB2488263A (en) * 2009-09-28 2012-08-22 Karl Imhoff Locking safety mechanism for suspended transport apparatus
US20110072580A1 (en) * 2009-09-28 2011-03-31 Karl Imhoff Locking Safety Mechanism for Suspended Transport Apparatus

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