CA2193735A1 - Winch - Google Patents
WinchInfo
- Publication number
- CA2193735A1 CA2193735A1 CA 2193735 CA2193735A CA2193735A1 CA 2193735 A1 CA2193735 A1 CA 2193735A1 CA 2193735 CA2193735 CA 2193735 CA 2193735 A CA2193735 A CA 2193735A CA 2193735 A1 CA2193735 A1 CA 2193735A1
- Authority
- CA
- Canada
- Prior art keywords
- worm
- drum
- rope
- winch
- drive
- 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.)
- Abandoned
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
- B66D1/00—Rope, cable, or chain winding mechanisms; Capstans
- B66D1/02—Driving gear
- B66D1/14—Power transmissions between power sources and drums or barrels
- B66D1/22—Planetary or differential gearings, i.e. with planet gears having movable axes of rotation
Abstract
Abstract Not Yet Available
Description
219~7~5 This invention relates to a winch. Especially this invention relates to a winch for lifting medium weight articles such as basketball backstops, or other gymnasium equipment.
Existing winches typically use belt or chain drives in conjunction with standard enclosed oil bath type worm drives. They tend to be bulky and heavy and require periodic adjustment of belts, etc. With extended use oil leaks can develop which is a hazard in gymnasium situations where oil may get on the floor.
With wear and polishing of the mating surfaces, even high ratio worn gears can "back-drive" under vibration conditions or when the inertia of the motor coupled with the dynamic lubrications causes the drum to continue in motion in the down direction after the power has been shut-off.
Winches of the type described may utilize rope or wire cable or wire. The term "rope" will be used herein to encompass all normally used winch cables.
Rope anchorage is frequently a weak point on conventional winches. Sometimes the rope is secured with only two set screws clamping its end.
The limit switches on conventional winches are typically contrived as an add-on feature requiring shaft couplings and careful alignment. Such switches are awkward to adjust accurately. Frequent problems occur when the rope either becomes slack on the drum and jumps out of the grooves where provided or does not track evenly across the drum creating undue wear on the rope and negating the setting of the limit switches.
21g3735 The present inventors have addressed the problems connected with conventional winches.
The present invention provides a winch having a chainless and beltless drive comprising two drives orthogonally arranged one to the other on a one piece moulded reduction gearing member. The reduction gearing member may conveniently be made from reinforced polymeric material. Such a one piece reduction gearing member may allow manufacture of a compact winch with drive integrity which may be improved over that of conventional winches.
Moreover, the number of components is reduced in comparison with those of conventional winches thereby potentially reducing cost and labour in manufacture.
A further advantage may be that the drive system utilizes self lubricating composite material eliminating the need for lubricating oil. As a result the winch may be installed in any orientation without concern for lubricant leakage.
An embodiment of the invention will now be described with reference to the drawings in which:
Figure 1 shows an isometric view of a winch according to the invention;
Figure 2 shows a front view of the winch of figure 1;
Figure 3 shows a side view of the winch as shown in Figure 1;
Figure 4 is a view from the side somewhat similar to Figure 3 but viewed from within the housing showing operation components;
Figure 5 is a simplified view of some of the essential working components of Figure 4;
Figure 6 is a view of the rope drum of the winch of the previous figures;
Figure 7 is a view of the one piece moulding reduction gearing member of the winch of the previous Figures;
Figures 8A and 8B show a view of a rope drum pressure roller for trapping rope in helical grooves of the rope drum; and Figure 9 shows an exploded view of the braking system for a winch as shown in the previous Figures.
The drawings show a winch 10 having a housing 12 and a electric motor 14. The winch housing is constructed of accurately interlocking plates to maintain accurate geometry of the gears and other working parts. The plates have intermeshing tongues and slots to ensure precise assembly and to absorb a portion of the shear loads in the frame assembly. This permits lighter construction of the housing with no decrease in safety factor.
Rope 16 usually is led vertically onto a rope drum 18 through a top aperture 20 in winch housing 12. However, the winch housing 12 may be provided with front aperture 22 and an aperture at the rear so that rope 16 may be lead onto the rope drum from the front or the rear. These alternative directions for leading the rope onto the rope drum 18 are best seen in Figure 4 where they are respectively labelled 16A and 16B.
The electric motor 14 has a drive shaft 24 extending into the winch housing 12, a drive worm 26 is provided on the drive shaft.
Within the winch housing 12 a two-stage, one piece moulded worm 28 has a primary worm 30 and secondary worm 32 at right angles to worm 30. Primary worm 30 engages drive 21937~5 worm 26 of electric motor 14 and secondary worm 32 engages a worm wheel 34 on rope drum 18. Worm 28 is a worm wheel moulded from Nylatron NSM. It may, however, also be moulded from other self-lubricating polymeric components such as teflon filled acetal or nylon. Primary worm 30 is provided as a series of axially angled gear grooves about an end portion of moulded worm drum 28. The gear grooves of worm 30 engage teeth of drive worm 26, the drive shaft of electric motor 14 extending at right angles to the axis of worm drum 28.
Secondary worm of worm drum 28 comprises a helical gear groove about the body of worm drum 28. The helical gear groove of secondary worm 32 engages the worm wheel 34 of rope drum 18, the axis of which is at right angles to the axis of worm drum 28. By this mechanism the rotation of electric motor 14 through drive shaft 24 is translated into rotation of rope drum 18 which is located at right angles to drive shaft 24. This relative location of gearing is best seen from Figures 4 and 5. In Figure 5 the drive worm 26 is shown rotated through 90~ for clarity although the actual position of drive worm 26 is shown in dotted lines.
The worm drum 28 has a cavity 36 in its lower end 38 for location on a bearing 40 on which worm drum is freely rotatable.
Worm drum 28 has a frustro-conical cavity 42 in its upper end 44 for engagement with a brake cone as will be described hereinafter.
Rope drum 18 comprises a hollow drum either cast in metal, e.g. aluminum, or moulded in one piece from reinforced self lubricating material similar to that used to form the worm drum 28. In one end region of rope drum 18, -worm wheel 34 comprises a narrow cylindrical part having axial gear grooves 46 lying between gear ridges 48. The body of the drum is provided with a helical groove 50 into which rope 16 is wound.
The operation of the winch thus far described is similar to the operation of conventional winches subject to the one part construction of worm drum 28 from self-lubricating material and the similar construction of rope drum 18. When drive shaft 24 is rotated by means of electric motor 14, drive worm 26 engages primary worm 30 of worm drum 28 to rotate worm drum 28 about its vertical axis as worm drum 28 rotates about its vertical axis worm 34 of rope drum 18 engages with helical secondary worm 32 of worm drum 28. Thus rope drum 18 is caused to rotate about its horizontal axis at right angles to drive shaft 24. As rope drum 18 rotates about its horizontal axis, rope 16 is wound onto the helical groove 50 thereof. The worm drum 28 operates as reduction gearing between the electric motor and the rope drum 18. The actual reduction is due to the angle of the gear grooves of worm 30 in respect to the axis of worm drum 28. The extent of the reduction gearing is dependent upon the loads on which the winch is to be used.
The first stage may for example have 17 teeth on wheel 26 mated with a 3-star worm 24 to give a 17:3 (5.66:1) ratio.
The second stage may have a ratio of 27:11 for a total of 153:1.
The rope drum 18 has a bearing projection at each end which bears in a bearing 52 of sidewalls of the housing 12.
The winch features an improved limit switch arrangement. The limit switch drive provides 3 time more travel of the limit switch trip nut per foot of rope wound on or off, giving much improved accuracy of the limit adjustments.
A further improvement is gained by providing slidable adjustment of the actual limit switches in place of the usual adjustment of the position of the travelling nut(s).
This is a much simplified and more accurate way of setting the stop positions.
A mechanism is provided for a travel limit switch drive for the rope. Below the rope drum 18 and parallel with it is a threaded shaft 54 having a gear wheel 56 thereon. The gear wheel 56 meshes with worm wheel 34 of rope drum 18. A
threaded shaft 54 has end bearings 58 located in bearing apertures of the sidewalls of housing 12. Threaded shaft 54 is rotated through meshing of drive wheel 56 with worm 34.
A travel nut 60 is provided on threaded shaft 54 which moves to and fro along the shaft in the axial direction on rotation of the shaft. A trip finger 62 depends from travel nut 60 to move between two limit switches 64. The position of at least one of the limit switches may be altered by sliding the switch 64 in a slot in the base of the housing, thus reducing or increasing the amount of travel allowed of travel nut 60 before trip finger 62 contacts switch 64 to switch off electric motor 14 to stop or change the speed of rope drum 18.
A braking system is provided which operates on the worm drum 28 rather than relying solely on a negative reverse efficiency of a worm gear drive system. The pre-loaded brake built into the worm drum 28 to ensure positive stopping and holding of the drum. A uni-directional clutch allows the brake to rotate with the drive pinion while running in the "up", or lifting, direction, but holds the brae cone stationary while lowering. The brake surface then generates frictional drag against the mating surface of the drive pinion, creating the required braking effect.
As has been described herein before, worm drum 28 rotates on bearing 40 at its lower end. At its upper end worm drum 28 is provided with an axial frustro-conical cavity 42. In its unbraked condition, when driven by electric motor 14, worm drum 28 rotates freely about a brake cone 70 located loosely and partially into in cavity 42 to locate the worm drum 28 in its vertical position. Brake cone 70 is uni-directional, i.e. it is rough and provides braking function in one direction of rotation of worm drum 28 and smooth to allow easy rotation in the other direction.
Brake cone 70 is movable into a braking position in which it moves further into cavity 42 and jams therein to prevent rotation of worm drum 28. A further unidirectional clutch 82 is provided.
Operation of the brake is described with reference to Figure 9. A top bearing bolt 72 passes through and aperture in a top wall of housing 12 and screw threadedly engages an axial socket of a bearing pin 74. Bearing 76 lies flush with an internal surface of the top wall of housing 12, pin 74 extends axially into a coil spring 80 which bears, on the one hand, against lower surface of washer 76 and, on the other hand, against brake cone 70 through washer 86 and bearing 88, biasing the brake cone 70 into engagement with worm drum 28 to stop rotation thereof.
The brake cone 70 is at all times in firm contact against cavity 42, the downward force being supplied by the spring 80. The spring does not rotate and the needle thrust (flat) bearing 88 allows the force to be applied without the spring rubbing against the brake cone. Therefore the top of _ -- 8 --worm 28 is firmly guided by the radial bearing capacity of the brake clutch 82.
Worm 28 and brake cone 70 rotate together in "up"
direction. The brake cone provides firm radial support but no drag in "down" direction. Uni-directional clutch 82 locks onto pin 74, holding brake cone 70 stationary and therefore provides braking torque via friction against the wall of cavity 42 while continuing to guide worm 28 radially.
Figure 9 also shows in more detail the lower bearing 40 of worm drum 48. Lower bearing 40 comprises a bearing bolt projecting through a worm thrust bearing 92 and a washer 94 flush with the lower surface of housing 12 and fixed by nut 96.
Figures 8A and 8B shows a small diameter roller located parallel with the body of rope drum 18. The small diameter roller 98 has a length corresponding to the body of rope drum 18 having helical groove 50. The roller 98 lies adjacent the helical groove 50 and traps rope in the helical grooves. The roller 98 has a resilient surface to enhance its action. The effectiveness of roller 98 is further enhanced by a pair of supporting torsion springs 100 which provide dual functions of both axels for roller 98 and a means of applying radial force to the roller 98. At least torsion spring 100 at the end of helical groove 50 containing the distal end of rope 16 may be arranged to supply substantial radial force to the roller. The torsion springs 98 also allow the roller to move out of parallel to the drum axis, thereby tending to exert additional pressure on the last turn of the rope on the drum which in turn prevents any loosening of preceding turns. The end of the rope is passed through a hole in the wall of the drum and doubled back through a standard U-clamp which pulls up against the inside of the diameter of the drum 18. Rope can not pull through this system and the radial force supplied by roller 98 enhances the security on the rope.
Existing winches typically use belt or chain drives in conjunction with standard enclosed oil bath type worm drives. They tend to be bulky and heavy and require periodic adjustment of belts, etc. With extended use oil leaks can develop which is a hazard in gymnasium situations where oil may get on the floor.
With wear and polishing of the mating surfaces, even high ratio worn gears can "back-drive" under vibration conditions or when the inertia of the motor coupled with the dynamic lubrications causes the drum to continue in motion in the down direction after the power has been shut-off.
Winches of the type described may utilize rope or wire cable or wire. The term "rope" will be used herein to encompass all normally used winch cables.
Rope anchorage is frequently a weak point on conventional winches. Sometimes the rope is secured with only two set screws clamping its end.
The limit switches on conventional winches are typically contrived as an add-on feature requiring shaft couplings and careful alignment. Such switches are awkward to adjust accurately. Frequent problems occur when the rope either becomes slack on the drum and jumps out of the grooves where provided or does not track evenly across the drum creating undue wear on the rope and negating the setting of the limit switches.
21g3735 The present inventors have addressed the problems connected with conventional winches.
The present invention provides a winch having a chainless and beltless drive comprising two drives orthogonally arranged one to the other on a one piece moulded reduction gearing member. The reduction gearing member may conveniently be made from reinforced polymeric material. Such a one piece reduction gearing member may allow manufacture of a compact winch with drive integrity which may be improved over that of conventional winches.
Moreover, the number of components is reduced in comparison with those of conventional winches thereby potentially reducing cost and labour in manufacture.
A further advantage may be that the drive system utilizes self lubricating composite material eliminating the need for lubricating oil. As a result the winch may be installed in any orientation without concern for lubricant leakage.
An embodiment of the invention will now be described with reference to the drawings in which:
Figure 1 shows an isometric view of a winch according to the invention;
Figure 2 shows a front view of the winch of figure 1;
Figure 3 shows a side view of the winch as shown in Figure 1;
Figure 4 is a view from the side somewhat similar to Figure 3 but viewed from within the housing showing operation components;
Figure 5 is a simplified view of some of the essential working components of Figure 4;
Figure 6 is a view of the rope drum of the winch of the previous figures;
Figure 7 is a view of the one piece moulding reduction gearing member of the winch of the previous Figures;
Figures 8A and 8B show a view of a rope drum pressure roller for trapping rope in helical grooves of the rope drum; and Figure 9 shows an exploded view of the braking system for a winch as shown in the previous Figures.
The drawings show a winch 10 having a housing 12 and a electric motor 14. The winch housing is constructed of accurately interlocking plates to maintain accurate geometry of the gears and other working parts. The plates have intermeshing tongues and slots to ensure precise assembly and to absorb a portion of the shear loads in the frame assembly. This permits lighter construction of the housing with no decrease in safety factor.
Rope 16 usually is led vertically onto a rope drum 18 through a top aperture 20 in winch housing 12. However, the winch housing 12 may be provided with front aperture 22 and an aperture at the rear so that rope 16 may be lead onto the rope drum from the front or the rear. These alternative directions for leading the rope onto the rope drum 18 are best seen in Figure 4 where they are respectively labelled 16A and 16B.
The electric motor 14 has a drive shaft 24 extending into the winch housing 12, a drive worm 26 is provided on the drive shaft.
Within the winch housing 12 a two-stage, one piece moulded worm 28 has a primary worm 30 and secondary worm 32 at right angles to worm 30. Primary worm 30 engages drive 21937~5 worm 26 of electric motor 14 and secondary worm 32 engages a worm wheel 34 on rope drum 18. Worm 28 is a worm wheel moulded from Nylatron NSM. It may, however, also be moulded from other self-lubricating polymeric components such as teflon filled acetal or nylon. Primary worm 30 is provided as a series of axially angled gear grooves about an end portion of moulded worm drum 28. The gear grooves of worm 30 engage teeth of drive worm 26, the drive shaft of electric motor 14 extending at right angles to the axis of worm drum 28.
Secondary worm of worm drum 28 comprises a helical gear groove about the body of worm drum 28. The helical gear groove of secondary worm 32 engages the worm wheel 34 of rope drum 18, the axis of which is at right angles to the axis of worm drum 28. By this mechanism the rotation of electric motor 14 through drive shaft 24 is translated into rotation of rope drum 18 which is located at right angles to drive shaft 24. This relative location of gearing is best seen from Figures 4 and 5. In Figure 5 the drive worm 26 is shown rotated through 90~ for clarity although the actual position of drive worm 26 is shown in dotted lines.
The worm drum 28 has a cavity 36 in its lower end 38 for location on a bearing 40 on which worm drum is freely rotatable.
Worm drum 28 has a frustro-conical cavity 42 in its upper end 44 for engagement with a brake cone as will be described hereinafter.
Rope drum 18 comprises a hollow drum either cast in metal, e.g. aluminum, or moulded in one piece from reinforced self lubricating material similar to that used to form the worm drum 28. In one end region of rope drum 18, -worm wheel 34 comprises a narrow cylindrical part having axial gear grooves 46 lying between gear ridges 48. The body of the drum is provided with a helical groove 50 into which rope 16 is wound.
The operation of the winch thus far described is similar to the operation of conventional winches subject to the one part construction of worm drum 28 from self-lubricating material and the similar construction of rope drum 18. When drive shaft 24 is rotated by means of electric motor 14, drive worm 26 engages primary worm 30 of worm drum 28 to rotate worm drum 28 about its vertical axis as worm drum 28 rotates about its vertical axis worm 34 of rope drum 18 engages with helical secondary worm 32 of worm drum 28. Thus rope drum 18 is caused to rotate about its horizontal axis at right angles to drive shaft 24. As rope drum 18 rotates about its horizontal axis, rope 16 is wound onto the helical groove 50 thereof. The worm drum 28 operates as reduction gearing between the electric motor and the rope drum 18. The actual reduction is due to the angle of the gear grooves of worm 30 in respect to the axis of worm drum 28. The extent of the reduction gearing is dependent upon the loads on which the winch is to be used.
The first stage may for example have 17 teeth on wheel 26 mated with a 3-star worm 24 to give a 17:3 (5.66:1) ratio.
The second stage may have a ratio of 27:11 for a total of 153:1.
The rope drum 18 has a bearing projection at each end which bears in a bearing 52 of sidewalls of the housing 12.
The winch features an improved limit switch arrangement. The limit switch drive provides 3 time more travel of the limit switch trip nut per foot of rope wound on or off, giving much improved accuracy of the limit adjustments.
A further improvement is gained by providing slidable adjustment of the actual limit switches in place of the usual adjustment of the position of the travelling nut(s).
This is a much simplified and more accurate way of setting the stop positions.
A mechanism is provided for a travel limit switch drive for the rope. Below the rope drum 18 and parallel with it is a threaded shaft 54 having a gear wheel 56 thereon. The gear wheel 56 meshes with worm wheel 34 of rope drum 18. A
threaded shaft 54 has end bearings 58 located in bearing apertures of the sidewalls of housing 12. Threaded shaft 54 is rotated through meshing of drive wheel 56 with worm 34.
A travel nut 60 is provided on threaded shaft 54 which moves to and fro along the shaft in the axial direction on rotation of the shaft. A trip finger 62 depends from travel nut 60 to move between two limit switches 64. The position of at least one of the limit switches may be altered by sliding the switch 64 in a slot in the base of the housing, thus reducing or increasing the amount of travel allowed of travel nut 60 before trip finger 62 contacts switch 64 to switch off electric motor 14 to stop or change the speed of rope drum 18.
A braking system is provided which operates on the worm drum 28 rather than relying solely on a negative reverse efficiency of a worm gear drive system. The pre-loaded brake built into the worm drum 28 to ensure positive stopping and holding of the drum. A uni-directional clutch allows the brake to rotate with the drive pinion while running in the "up", or lifting, direction, but holds the brae cone stationary while lowering. The brake surface then generates frictional drag against the mating surface of the drive pinion, creating the required braking effect.
As has been described herein before, worm drum 28 rotates on bearing 40 at its lower end. At its upper end worm drum 28 is provided with an axial frustro-conical cavity 42. In its unbraked condition, when driven by electric motor 14, worm drum 28 rotates freely about a brake cone 70 located loosely and partially into in cavity 42 to locate the worm drum 28 in its vertical position. Brake cone 70 is uni-directional, i.e. it is rough and provides braking function in one direction of rotation of worm drum 28 and smooth to allow easy rotation in the other direction.
Brake cone 70 is movable into a braking position in which it moves further into cavity 42 and jams therein to prevent rotation of worm drum 28. A further unidirectional clutch 82 is provided.
Operation of the brake is described with reference to Figure 9. A top bearing bolt 72 passes through and aperture in a top wall of housing 12 and screw threadedly engages an axial socket of a bearing pin 74. Bearing 76 lies flush with an internal surface of the top wall of housing 12, pin 74 extends axially into a coil spring 80 which bears, on the one hand, against lower surface of washer 76 and, on the other hand, against brake cone 70 through washer 86 and bearing 88, biasing the brake cone 70 into engagement with worm drum 28 to stop rotation thereof.
The brake cone 70 is at all times in firm contact against cavity 42, the downward force being supplied by the spring 80. The spring does not rotate and the needle thrust (flat) bearing 88 allows the force to be applied without the spring rubbing against the brake cone. Therefore the top of _ -- 8 --worm 28 is firmly guided by the radial bearing capacity of the brake clutch 82.
Worm 28 and brake cone 70 rotate together in "up"
direction. The brake cone provides firm radial support but no drag in "down" direction. Uni-directional clutch 82 locks onto pin 74, holding brake cone 70 stationary and therefore provides braking torque via friction against the wall of cavity 42 while continuing to guide worm 28 radially.
Figure 9 also shows in more detail the lower bearing 40 of worm drum 48. Lower bearing 40 comprises a bearing bolt projecting through a worm thrust bearing 92 and a washer 94 flush with the lower surface of housing 12 and fixed by nut 96.
Figures 8A and 8B shows a small diameter roller located parallel with the body of rope drum 18. The small diameter roller 98 has a length corresponding to the body of rope drum 18 having helical groove 50. The roller 98 lies adjacent the helical groove 50 and traps rope in the helical grooves. The roller 98 has a resilient surface to enhance its action. The effectiveness of roller 98 is further enhanced by a pair of supporting torsion springs 100 which provide dual functions of both axels for roller 98 and a means of applying radial force to the roller 98. At least torsion spring 100 at the end of helical groove 50 containing the distal end of rope 16 may be arranged to supply substantial radial force to the roller. The torsion springs 98 also allow the roller to move out of parallel to the drum axis, thereby tending to exert additional pressure on the last turn of the rope on the drum which in turn prevents any loosening of preceding turns. The end of the rope is passed through a hole in the wall of the drum and doubled back through a standard U-clamp which pulls up against the inside of the diameter of the drum 18. Rope can not pull through this system and the radial force supplied by roller 98 enhances the security on the rope.
Claims
Claims Not Yet Available
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2193735 CA2193735A1 (en) | 1996-12-20 | 1996-12-20 | Winch |
| CA002201046A CA2201046A1 (en) | 1996-12-20 | 1997-03-26 | Winch |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2193735 CA2193735A1 (en) | 1996-12-20 | 1996-12-20 | Winch |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2193735A1 true CA2193735A1 (en) | 1998-06-20 |
Family
ID=4159510
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2193735 Abandoned CA2193735A1 (en) | 1996-12-20 | 1996-12-20 | Winch |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2193735A1 (en) |
-
1996
- 1996-12-20 CA CA 2193735 patent/CA2193735A1/en not_active Abandoned
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5803437A (en) | Chainless drive winch | |
| EP0851982B1 (en) | Improvements in electrically-operated disc brake assemblies for vehicles | |
| US7331252B2 (en) | Braking system | |
| US8925412B2 (en) | Safety system | |
| JP2587026B2 (en) | Flow blockage device | |
| US20080156132A1 (en) | Safety system | |
| US3802290A (en) | Roller nut assembly | |
| US3150744A (en) | Individual safety elevator | |
| DE2919216A1 (en) | Rope speed limited abseiling mechanism - has single overhung pulley outside housing and driving gear for centrifugal brake | |
| CA2193735A1 (en) | Winch | |
| GB2091375A (en) | A device for converting rotary motion into linear motion | |
| CA2201046A1 (en) | Winch | |
| US4582177A (en) | Braking device with mechanical actuation | |
| EP0526461A1 (en) | Shut-off valve. | |
| KR890002080B1 (en) | Excessive load prevention apparatus employable for a hoist or the like | |
| KR102199659B1 (en) | Lift drive system for stage equipment without electronic brake | |
| EP0070290A1 (en) | Reeling device. | |
| WO2005005854A1 (en) | An electromechanical linear actuator for a service brake of a motor vehicle | |
| DE102008050993B4 (en) | spindle motor | |
| US2668036A (en) | Cable and reel for lowering objects of different weight at constant speed | |
| US8057346B2 (en) | Automatic stepless transmission | |
| DD274401A5 (en) | ELECTRIC CHAIN CABLE WITH CHANGEABLE SPEED CHANGE | |
| CN219527104U (en) | Power system of clothes airing machine and clothes airing machine | |
| EP0357575A2 (en) | Device for retarding a torque-transferring member | |
| US6109125A (en) | Linear drive mechanism including a slip clutch |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |