US983120A - Safety shaft-sinking cross-head. - Google Patents

Safety shaft-sinking cross-head. Download PDF

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Publication number
US983120A
US983120A US44023408A US1908440234A US983120A US 983120 A US983120 A US 983120A US 44023408 A US44023408 A US 44023408A US 1908440234 A US1908440234 A US 1908440234A US 983120 A US983120 A US 983120A
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head
cross
guides
crosshead
normally
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US44023408A
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Thomas Bryant
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ARTHUR H WETHEY
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ARTHUR H WETHEY
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B5/00Applications of checking, fault-correcting, or safety devices in elevators
    • B66B5/02Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions
    • B66B5/08Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions for preventing overwinding
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B5/00Applications of checking, fault-correcting, or safety devices in elevators
    • B66B5/02Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions
    • B66B5/16Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well
    • B66B5/18Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well and applying frictional retarding forces
    • B66B5/20Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well and applying frictional retarding forces by means of rotatable eccentrically-mounted members

Definitions

  • One object of this invention is to provide automatically operating means to lock a movable crosshead firmly against movement, whenever the cross-head is accidentally caught or lodged in the shaft.
  • Another object of the invention is to provide means, whereby the bucket, car or other carrier may be lowered independently of the cross-head after same has become lodged and whereby the crosshead may be automatically released when the carrier is raised.
  • Figure 1 represents a front view of a portion of a shaft with a cross-head and carrier therein comprising my improved mechanism.
  • Fig. 2 represents an end view of the same, with one of the guides removed to more clearly show the parts of the mechanism.
  • Fig. 3 is a plan view of the same.
  • Fig. -.t is a detailed view, showing the tube or sheath.
  • the frame of the crosshead may be of the usual construction comprising upper and lower cross-bars a, platform 6, braces c, and side arms (Z.
  • the side arms are provided with shoes 0 which travel on guides f constructed in the shaft in the usual manner.
  • the cross-bars are provided centrally with passages 9 such as are usually provided for the traction member which may be a cable, rope, chain or other hoisting means.
  • the skep, cage, bucket, car or other carrier h is secured to the traction member 2' by any suitable means as a. shackle j preferably having a head is formed thereon which normally engages the bottom of the lower cross-bar and provides a central support for the crosshead.
  • V shackle j preferably having a head is formed thereon which normally engages the bottom of the lower cross-bar and provides a central support for the crosshead.
  • a movable member comprising prefer- Specification of Letters Patent.
  • a tube or sheath Z incloses the lower portion of the traction member and is movably mounted on the cross-bars preferably in passages 9. Normally this member Z rests upon and is supported by the head A: of the shackle, but when such support is withdrawn downward movement thereof is limited in any suitable manner as by a collar m.
  • the upper part of the tube or sheath referably projects a short distance above tie upper cross-bar and has ropes or chains a secured to opposite sides thereof preferably to the collar m. Each chain is operatively connected with a pulley or sheave p keyed to a shaft Q rotatable in suitable bearings 1 provided in the frame.
  • One or more stout springs s are secured to each shaft near both ends thereof in such manner that they will act normally to rotate the shaft and wind up the chains upon the sheaves or pulleys p.
  • a safety device to engage the guides comprising preferably a dog t is rigidly secured to the end of each shaft.
  • Said safety dog is preferably segmental in form and is provided with a toe or extension a and with teeth 4; adapted to bite into and rigidly engage with the guide and hold the crosshead against movement.
  • the crosshead When the crosshead is operating in its usual and normal manner, it rests upon the shackle or other holding means and moves up and down upon the guides with the traction member.
  • the tube or sheath Z is held in its raised position (shown in solid lines in Fig. l) which pulls upon the chains a and holds the dogstin their non-operative positions against the tension of the springs s. lVhen, however, the crosshead strikes any obstruction or sticks accidentally or otherwise on the guides for any reason whatever while the traction cable is descending, then the rope with the carrier attached will continue its downward movement independently of the crosshead.
  • the shackle disengages from the lower end of the sheath or tube Z which thereupon drops, by gravity and under the tension of the springs .9, into its lowermost position (shown in dotted lines in Fig. 1) and simultaneously the springs rotate the shafts g to bring the teeth 1) on the dogs into engagement with the guides.
  • the crosshead will thus be securely held until the bucket or other receptacle is raised again and the traction cable engages with and raises the tube, thereby rotating the shafts g by means of the chains 12 and returning the dogs to their non-operative positions against the tension of the springs 8.
  • a safety shaft sinking device the combination of a cross-head, a traction member freely movable with respect to said crosshead and provided with means normally supporting same, and a safety device on said cross-head normally held in non-operative position by the traction member while the cross-head is supported by said traction member, said safety device being operated immediately to prevent positively down ward movement of the cross-head whenever the cross-head is supported independently of the traction member.
  • a safety shaft sinking device the combination with. guides and a cross-head movable on said guides, of a traction member freely movable with respect to said crosshead and provided with means normally supporting same, and a safety device on said cross-head comprising gripping members normally held in non-operative position by the traction member while the cross-head is supported by said traction member, said safety device being immediately operated to engage positively with the guides to prevent downward movement of the cross -head whenever the support provided by the traction member is withdrawn.
  • a safety shaft sinking device the combination with a cross-head and a safety device on said cross-head, of a movable tube operatively connected with said safety device and movable independently of the cross head, a traction member normally supporting the cross-head and provided with means normally engaging said movable tube to hold the safety device in its non-operative position, and means causing said safety device to operate immediately when said traction member moves independently of the cross-head to hold the cross-head positively against downward movement.
  • a safety device on said crosshead comprising gripping members adapted to engage the guides in their operative position, an operating member mounted on the crosshead and movable with relation thereto and operatively secured to the gripping members, said operating member normally engaging with the traction member while the cross-head is supported thereby to hold said gripping members in non-operative position and being automatically released to permit operation of said gripping members when the traction member moves independently of the crosshead and the support provided thereby is withdrawn, and means for causing said safety device to operate immediately when said traction member moves independently of the cross-head to hold the cross-head positively against downward movement.
  • a safety shaft sinking device comprising a rigid frame having upper and lower cross-bars, safety devices mounted on said crosshead adapted to engage the guides in their operative position, and a tube mounted on the upper and lower cross-bars and movable independently thereof and connected with the safety devices, of a traction member freely movable with respect to and normally supporting said cross-head and engaging said tube to hold the safety devices in their non-operative position, and means for actuating said safety devices immediately to engage the guides whenever the cross-head is supported independently of the traction member.
  • the combination with guides and a crosshead guided by said guides comprising horizontal members provided with central openings therein; a tube movably mounted in said openings; a hoisting cable freely and independently movable in said tube; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said crosshead; a safety device carried by said crosshead and comprising swinging gripping members normally out of contact with said guides but adapted to come into contact therewith when said carrier moves away from said crosshead; a spring acting upon said gripping members to move them into positive contact with said guides immediately when the carrier is supported inclependently of the cross-head; means connecting said tube and said gripping members through which motion is transmitted in one direction from said tube to said gripping members; and means carried by and movable with said hoisting cable and adapted to normally engage the tube to hold said gripping members out of contact with said guides and to support the crosshead.

Description

T. BRYANT.
SAFETY SHAFT SINKING CROSS HEAD.
APPLICATION FILED JUHBQB, 190B.
Patented Jan.31,1911.
3 SHEETS-SHEET 1.
Inventor- A w lulu-O W M 7 A tist.
1- IE .voxms PETERS ca., WASHINGTON, n. c.
I T. BRYANT. SAFETY SHAFT SINKING GROSS HEAD.
APPLICATION FILED JUNE 26, 1908.
Patented Jan. 31, 1911.
3 SHEETS-SHEET 2,
Inventor:
.W QOQQQ co, WASHINGTON, n. c.
T. BRYANT. SAFETY-SHAFT SINKING GROSS HEAD.
APPLICATION 211.21) JUNE 25. 1908.
Patented Jan. 31, 1911.
Q i y Inventor:
Attys.
7H5 NORRIS PETERS co wnsumaz'om a c.
THOMAS BRYAN T,
OF BUTTE, MONTANA, ASSIGNOR 0F ONE-HALF T0 ARTHUR H.
WETHEY, OF BUTTE, MONTANA.
SAFETY SHAFT-SINKING- CROSS-HEAD.
To all whom it may concern:
Be it known that I, THOMAS BRYAN'I, a citizen of the United States, residing at Butte, in the county of Silverbow, in the State of Montana, have invented certain new and useful Improvements in Safety Shaft- Sinking Cross-Heads, of which the following is a specification, reference being had to the accompanying drawings, forming a part hereof.
One object of this invention is to provide automatically operating means to lock a movable crosshead firmly against movement, whenever the cross-head is accidentally caught or lodged in the shaft.
Another object of the invention is to provide means, whereby the bucket, car or other carrier may be lowered independently of the cross-head after same has become lodged and whereby the crosshead may be automatically released when the carrier is raised.
Still further objects will be set forth in the description of the invention, which consist in the new and novel features of construction and combination of parts hereinafter set forth and claimed.
In the accompanying drawings, Figure 1 represents a front view of a portion of a shaft with a cross-head and carrier therein comprising my improved mechanism. Fig. 2 represents an end view of the same, with one of the guides removed to more clearly show the parts of the mechanism. Fig. 3 is a plan view of the same. Fig. -.t is a detailed view, showing the tube or sheath.
Referring to the drawings and to the particular embodiment of my invention therein shown, the frame of the crosshead may be of the usual construction comprising upper and lower cross-bars a, platform 6, braces c, and side arms (Z. The side arms are provided with shoes 0 which travel on guides f constructed in the shaft in the usual manner. The cross-bars are provided centrally with passages 9 such as are usually provided for the traction member which may be a cable, rope, chain or other hoisting means.
The skep, cage, bucket, car or other carrier h is secured to the traction member 2' by any suitable means as a. shackle j preferably having a head is formed thereon which normally engages the bottom of the lower cross-bar and provides a central support for the crosshead. V
A movable member comprising prefer- Specification of Letters Patent.
Application filed June 25, 1908.
Patented Jan. 31, 1911. Serial No. 440,234.
ably a tube or sheath Z incloses the lower portion of the traction member and is movably mounted on the cross-bars preferably in passages 9. Normally this member Z rests upon and is supported by the head A: of the shackle, but when such support is withdrawn downward movement thereof is limited in any suitable manner as by a collar m. The upper part of the tube or sheath referably projects a short distance above tie upper cross-bar and has ropes or chains a secured to opposite sides thereof preferably to the collar m. Each chain is operatively connected with a pulley or sheave p keyed to a shaft Q rotatable in suitable bearings 1 provided in the frame. One or more stout springs s are secured to each shaft near both ends thereof in such manner that they will act normally to rotate the shaft and wind up the chains upon the sheaves or pulleys p. A safety device to engage the guides comprising preferably a dog t is rigidly secured to the end of each shaft. Said safety dog is preferably segmental in form and is provided with a toe or extension a and with teeth 4; adapted to bite into and rigidly engage with the guide and hold the crosshead against movement.
When the crosshead is operating in its usual and normal manner, it rests upon the shackle or other holding means and moves up and down upon the guides with the traction member. The tube or sheath Z is held in its raised position (shown in solid lines in Fig. l) which pulls upon the chains a and holds the dogstin their non-operative positions against the tension of the springs s. lVhen, however, the crosshead strikes any obstruction or sticks accidentally or otherwise on the guides for any reason whatever while the traction cable is descending, then the rope with the carrier attached will continue its downward movement independently of the crosshead. The shackle disengages from the lower end of the sheath or tube Z which thereupon drops, by gravity and under the tension of the springs .9, into its lowermost position (shown in dotted lines in Fig. 1) and simultaneously the springs rotate the shafts g to bring the teeth 1) on the dogs into engagement with the guides. The crosshead will thus be securely held until the bucket or other receptacle is raised again and the traction cable engages with and raises the tube, thereby rotating the shafts g by means of the chains 12 and returning the dogs to their non-operative positions against the tension of the springs 8.
By this construction the disasters caused by the falling of the crosshead upon the car rier, such as a bucket, skep or car, after being accidentally caught on the guides will be effectually prevented since the dogs engage automatically the moment that the crosshead is caught in any part of the shaft. At the same time the cable is always free to move independently of the crosshead and if the crosshead should be caught no delay is 0ccasioned thereby as the cable can be lowered 'as far as desired and then, when raised again, the crosshead will be automatically released. In case the traction cable breaks it is obvious that the safety means will operate automatically in the same manner as when the crosshead is accidentally caught and will prevent the crosshead from falling to the bottom of the shaft.
Although my improved mechanism can be used in any situation it is especially adapted for use in shaft sinking and in various other places where it is necessary to lower the bucket or other receptacle below the end of the guides, since a stop or other obstruction placed at the ends of the guides will cause the safety device to operate and hold the crosshead positively and independently while the bucket is lowered to the bottom. It is obvious, however, that the crosshead or an equivalent thereof can be used in connection with hoists, elevators or carriers of any kind which move in guides and which require safety appliances that will work automatically to hold the same positively against movement in one direction.
Various changes and modifications in the details of the structure shown and described herein will readily occur to those skilled in the art, but all such changes and modifications are within the scope of my invention provided the means set forth in the following claims be employed.
I claim as my invention:
1. In a safety shaft sinking device the combination of a cross-head, a traction member freely movable with respect to said crosshead and provided with means normally supporting same, and a safety device on said cross-head normally held in non-operative position by the traction member while the cross-head is supported by said traction member, said safety device being operated immediately to prevent positively down ward movement of the cross-head whenever the cross-head is supported independently of the traction member.
2. In a safety shaft sinking device, the combination with. guides and a cross-head movable on said guides, of a traction member freely movable with respect to said crosshead and provided with means normally supporting same, and a safety device on said cross-head comprising gripping members normally held in non-operative position by the traction member while the cross-head is supported by said traction member, said safety device being immediately operated to engage positively with the guides to prevent downward movement of the cross -head whenever the support provided by the traction member is withdrawn.
3. In a safety shaft sinking device, the combination with a cross-head and a safety device on said cross-head, of a movable tube operatively connected with said safety device and movable independently of the cross head, a traction member normally supporting the cross-head and provided with means normally engaging said movable tube to hold the safety device in its non-operative position, and means causing said safety device to operate immediately when said traction member moves independently of the cross-head to hold the cross-head positively against downward movement.
4. In a safety shaft sinking device, the combination of guides, a cross-head movable on said guides, a traction member freely movable with respect to said cross-head and provided with means normally supporting same, a safety device on said crosshead comprising gripping members adapted to engage the guides in their operative position, an operating member mounted on the crosshead and movable with relation thereto and operatively secured to the gripping members, said operating member normally engaging with the traction member while the cross-head is supported thereby to hold said gripping members in non-operative position and being automatically released to permit operation of said gripping members when the traction member moves independently of the crosshead and the support provided thereby is withdrawn, and means for causing said safety device to operate immediately when said traction member moves independently of the cross-head to hold the cross-head positively against downward movement.
5. In a safety shaft sinking device, the combination with guides, a cross-head comprising a rigid frame having upper and lower cross-bars, safety devices mounted on said crosshead adapted to engage the guides in their operative position, and a tube mounted on the upper and lower cross-bars and movable independently thereof and connected with the safety devices, of a traction member freely movable with respect to and normally supporting said cross-head and engaging said tube to hold the safety devices in their non-operative position, and means for actuating said safety devices immediately to engage the guides whenever the cross-head is supported independently of the traction member.
6. The combination with guides and a cross-head guided by said guides, of a hoist ing cable adapted to normally support said cross-head and to move freely and independent of said cross-head in the direction of motion thereof; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said cross-head and free at all times to move away therefrom; a safety device carried by said crosshead, means for causing said safety device immediately to engage positively with the guides when said carrier moves away from said cross-head; and means carried by and movable with said hoisting cable and adapted to normally engage said safety device to hold it in its inoperative condition, said means serving also as a support for said crosshead.
7. The combination with guides and a cross-head guided by said guides, of a hoisting cable adapted to normally support said cross-head and to move freely and inclependeut of said cross-head in the direction of motion thereof; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said cross-head and free at all times to move away therefrom; a safety device carried by said cross head and normally inoperative, means for causing immediate operation of said safety device when said carrier moves away from said cross-head to hold the cross-head positively against downward movement; and means carried by and movable with said hoisting cable and adapted to normally engage said safety device to hold it in its inoperative condition, said means serving also as a support for said cross-head.
S. The combination with guides and a cross-head guided by said guides, of a hoist; ing table adapted to normally support said cross-head and to move freely and independently of said cross-head in the direction of motion thereof; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said cross-head and free at all times to move away therefrom; a safety device carried by said cross-head and comprising movable members normally out of contact with said guides but adapted to come into contact therewith when said carrier moves away from said cross-head; means for operating said movable members immediately when the carrier moves away from the cross-head to hold said cross-head positively against downward movement; and means carried by and movable with said hoisting cable and adapted to normally engage said operating means to hold said movable members out of contact with said guides, said means serving also as a support for said cross-head.
9. The combination with guides and a cross-head guided by said guides, of a hoisting cable adapted to normally support said cross-head and to move freely and inclependent of said cross-head in the direction of motion thereof; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said cross-head and free at all times to move away therefrom; a safety device carried by said crosshead and comprising s\\"inging gripping members normally out of contact with said guides but adapted to come into contact therewith when said carrier moves away from said cross-head; a movable tube carried by said cross-head and through which said hoisting cable passes; means connecting said tube and said gripping members and through which motion is transmitted from said tube to said gripping members; means for causing said gripping members to engage immediately with said guides to hold the cross-head positively against downward movement; and means carried by and movable with said hoisting cable and adapted to normally engage said tube to hold said guides said means serving also as a support for said cross-head.
10. The combination with guides and a crosshead guided by said guides, of a hoisting cable adapted to normally support said cross-head and to move freely and independent of said cross-head in the direction of motion thereof; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said cross-head and free at all times to move away therefrom; a safety device carried by said cross-head and comprising swinging gripping members normally out of contact with said guides but adapted to come into contact therewith when said. carrier moves away from said crosshead; means acting upon said gripping members nnmediately whenever the crosshead is supported independently of the hoisting cable to move them into positive contact with said guides; a movable tube carried by said cross-head and through which said hoisting cable passes; means connecting said tube and said gripping members and through which motion is transmitted from said tube to said gripping members; and means carried by and movable with said hoisting cable and adapted to normally engage said tube to hold said gripping members out of contact with said guides said means serving also as a support for said cross-head.
11. The combination with guides and a cross-head guided by said guides, of a hoisting cable adapted to normally support said cross-head and to move freely and independent of said cross-head in the direction of motion thereof; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said cross-head and free gripping members out of contact with said at all times to move away therefrom; a safety device carried by said cross-head and comprising swinging gripping members normally out of contact with said guides but adapted to come into contact therewith when said carrier moves away from said crosshead; a spring acting upon said gripping members to move them immediately into positive contact with said guides when the carrier moves away from the cross-head; a movable tube carried by said cross-head and through which said hoisting cable passes; means connecting said tube and said gripping members and through which motion is transmitted from said tube to said gripping members; and means carried by and movable with said hoisting cable and adapted to normally engage said tube to hold said gripping members out of contact with said guides, said means serving also as a support for said cross-head.
12. The combination with guides and a crosshead guided by said guides comprising horizontal members provided with central openings therein; a tube movably mounted in said openings; a hoisting cable freely and independently movable in said tube; a carrier supported by said hoisting cable and adapted to receive a load and located beneath said crosshead; a safety device carried by said crosshead and comprising swinging gripping members normally out of contact with said guides but adapted to come into contact therewith when said carrier moves away from said crosshead; a spring acting upon said gripping members to move them into positive contact with said guides immediately when the carrier is supported inclependently of the cross-head; means connecting said tube and said gripping members through which motion is transmitted in one direction from said tube to said gripping members; and means carried by and movable with said hoisting cable and adapted to normally engage the tube to hold said gripping members out of contact with said guides and to support the crosshead.
This specification signed and witnessed this 12th day of May, A. 1)., 1908.
THOMAS BRYANT.
Signed in the presence of WV. C. MEssIA-s, JAMES DOUEL.
US44023408A 1908-06-25 1908-06-25 Safety shaft-sinking cross-head. Expired - Lifetime US983120A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2507046A (en) * 1948-06-08 1950-05-09 Richard H Pearce Safety catch for elevators and the like
US3217837A (en) * 1958-04-07 1965-11-16 Chicago Pneumatic Tool Co Track guide means for jumbo shaft drills

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2507046A (en) * 1948-06-08 1950-05-09 Richard H Pearce Safety catch for elevators and the like
US3217837A (en) * 1958-04-07 1965-11-16 Chicago Pneumatic Tool Co Track guide means for jumbo shaft drills

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