Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
  • B66D3/00—Portable or mobile lifting or hauling appliances
  • B66D3/18—Power-operated hoists
  • B66D3/20—Power-operated hoists with driving motor, e.g. electric motor, and drum or barrel contained in a common housing
  • B66D3/22—Power-operated hoists with driving motor, e.g. electric motor, and drum or barrel contained in a common housing with variable-speed gearings between driving motor and drum or barrel
• • 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
  • B66D1/28—Other constructional details
  • B66D1/40—Control devices
  • B66D1/42—Control devices non-automatic
  • B66D1/44—Control devices non-automatic pneumatic of hydraulic
• • 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
  • B66D1/54—Safety gear
  • B66D1/56—Adaptations of limit switches

Definitions

• This invention relates to a piston and drum drive system and more particularly to a compact structure wherein a drum drive and a piston actuating drive are positioned within the hollow interior of the drum and operate to turn the drum and to actuate the piston in a desired direction.
• Applicant has devised a piston and drum drive structure in which most of the inefficiencies described above have been eliminated, both as to use of space and as to energy consumption.
• the electric motor By placing the electric motor inside the drum and using its shaft output to drive the drum directly through a gear set, the hydraulic line losses in driving the drum are eliminated and the hydraulic motor is totally eliminated.
• the opposite end of the motor shaft is connected directly or through a clutch to a compact anifold structure also within the drum.
• the drum further contains the hydraulic pump, two hydraulic accumulators, certain necessary relief valves and check valves and interconnecting lines which are very short, leaving as the only external lines those from the manifold to the external drive piston.
• Figure 1 is a longitudinal drawing partly in section of a piston and drum drive structure according to the invention
• Figure 2 is a schematic diagram of the hydraulic circuit employed in the system;
• Figure 3 is a side view of the manifold shown in Fig. i;
• Figure 4 is a sectional view along line 4-4 of Fig. 3;
• Figure 5 is a view from the rear of the manifold of figure 3.
• Figure 6 is a partial sectional view through the hydraulic manifold structure employed in the system;
• Figure 7 is a sectional view of the manifold of Figures 3 through 6 taken along line 7-7 of Figure 6;
• Figure 8 is a sectional view of the manifold of Figures 3 through 6 taken along line 8-8 of Figure 6.
• Figure 9 is a schematic drawing of an alternate form of motor assembly incorporated into the structure of Figure 1.
• a piston and drum drive structure including a drum 10 rotatably supported in mounting brackets 12, 14.
• Drum 10 carries two sets of spiral left and right hand grooves 16, 18 which support cables (not shown) for reeling a load out (down) from the drum and pulling it in (or up) .
• Carried within the drum is a D.C. motor 20 having an output shaft 22.
• Attached to shaft 22 is a pinion gear 24 which drives a gear reduction gear set including gears 26, 27, and 28.
• Gear 28 is carried on a shaft 30 which includes a lead screw and a follower 32 operable between a pair a limit switches 34, 36 whose function is to cause rotation of the drum 10 to stop and to reset the polarity of the electric motor drive so that when next energized, the motor 20 will turn in the opposite direction.
• a pinion 38 At the opposite end of shaft 30 is a pinion 38 which drives an internal gear 40 on the inside surface of the drum 10.
• shaft 22 is connected to an hydraulic power generating system 21 and in particular to an hydraulic pump thereof which is part of a manifold structure 42.
• an accumulator 44 including a piston 46 and a spring 48.
• the manifold 42 including the motor-driven pump, supplies hydraulic fluid under pressure to an external actuating cylinder 47 including a piston 49 through a pair of conduits 50, 52.
• This manifold is described in greater detail in connection with Figures 3 through 8.
• Also part of manifold 42 is an axially extending boss 51 including a bearing 53 supporting one end of drum 10.
• the hydraulic circuit of the above described system is shown in schematic form on Figure 2 and includes a pump 54 driven by shaft 22 which is reversible along with motor 20 to supply hydraulic fluid under substantial pressure to either of conduits 56 or 58. These conduits connect directly with hydraulic accumulators 44 and 45, respectively.
• a pair of oppositely directed relief valves 60 and 62 set to pressure levels somewhat above the normal operating pressure are connected to lines 56 and 58 through -4- conduits 64 and 66 respectively such that they are connected across the pump outlet in each direction.
• Conduit 56 is connected through a conduit 64 to a check valve 67 and an oppositely directed relief valve 68. These valves are connected through conduit 50 to one side of a piston 49 in a cylinder 47.
• Conduit 58 is connected through a conduit 74 to a check valve 76 and an oppositely directed relief valve 78, which valves are connected through conduit 52 to the opposite side of piston 49.
• pump 54 to supply fluid under pressure to accumulator 44 and through check valve 67 and conduit 50 to the left side of piston 49, causing piston 49 to move toward the right.
• This will force fluid from the right side of cylinder 47 through conduit 52 and relief valve 78 to the conduit 58 and the opposite side of the pump 54.
• the fluid will also build pressure in accumulator 45 whose primary purpose is to assure adeguate fluid pressure on the inlet side of the pump to avoid cavitation.
• FIG. 3 is a side view of the manifold 42 including the hydraulic gear pump 54 and a support structure 80.
• Figure 4 is a sectional view taken along line 4-4 of Figure 3.
• pump 54 is a conventional gear pump including a driving gear 84 carried on the motor shaft 22 and a driven gear 86 carried on a stub shaft 88 supported in the housing of manifold 42 and support structure 80.
• the side of support structure 80 facing the electric motor 20 is shown in Figure 5. In this view is shown a recess 90 receiving a boss which supports -5- motor shaft 22.
• Structure 80 is bolted to the housing of manifold 42 by means of a plurality of screws 92.
• Figure 6 is a view of manifold 42, partly in section, which shows the opposite side from that shown in Figure 3.
• high pressure lines 64, 65 which receive hydraulic fluid under pressure from pump 54.
• line 64 communicates with a chamber 98 which receives the output from pump 54 (Fig. 8) .
• a second high pressure line 66 which communicates with a second output chamber 100.
• Chamber 100 is connected with accumulator 44 through a short passage 56.
• a similar short passage 58 connects chamber 98 with accumulator 45 which includes a piston 104 and a spring 106 (Fig. 6) .
• bushings 108 and 110 which align and support shafts 22 and 88 carrying pump gears 84 and 86.
• the high pressure relief valves 62 and 60 are also shown connected between the high pressure lines 64 and 66.
• Boss 51 is shown in Figure 6 and in phantom in Figure 8.
• Figure 7, which is a sectional view taken along line 7-7 of Figure 6 cuts through both of accumulators 44 and 45 as well as a number of controlled pressure lines carrying relief valves 68 and 78.
• On the downstream side of relief valves 68 and 78 are outlet passages 50 and 52 which lead to the actuating cylinder 47. The ends of the passages shown are plugged since it is necessary to form the various passages by drilling into the manifold 42 and then inserting plugs where needed to close the ends.
• Motor assembly 120 includes, in addition to the motor, a clutch 124 and a brake assembly 126, both of which are mounted on and coaxial with the motor shaft 122. While the clutch and brake can be electronically and mechanically connected in a number of operating configurations, an arrangement which has been used by the applicant operates with the brake normally engaged with the drum, (deenergized) which locks the drum to its mounting structure preventing the drum from rotating and holding the suspended load in position. When the brake 126 is energized, it is released and the motor 120 then drives the drum as desired to raise or lower the load. In this arrangement the pump 54 is always connected to the motor 120 so that the piston is actuated whether or not the load is raised or lowered.
• the brake assembly 126 may be manually operated or it may be connected into a drum drive control system which includes means to secure shaft 122 in a desired position and/or to sense the approach of the load to either its fully extended position or its fully retracted position such that the cables are prevented from receiving a severe shock either from having the load stopped suddenly at the end of the cable track, or from striking an obstacle at the fully retracted position.
• an electrical request to lower or pay out a load from the drum results in causing the motor 20 to turn in such direction as to reel the load out and simultaneously to drive the pump 54 to move piston 49 to the right in cylinder 47 (as shown in Fig. 2) . Fluid from the right side of piston 47 will then return to the pump 54 as described above. A request to raise the load will cause the electric motor 20 to rotate in the opposite direction, turning drum 10 in the direction to reel the load in (or up) . At this time, the pump 54 will be turned in the opposite direction causing piston 49 to move to the left. In the event that motor assembly 120 of Figure 9 is used, initial operation of the motor may occur with the clutch 124 disengaged such that the pump turns but the drum does not turn.
• the drum 10 may be desired to delay operation of the drum 10 until the pump 54 is at or near the end of its cycle or to defer operating the drum 10 at all for some cycles. On the return part of the cycle, it may be that the operator will want the drum 10 to -7- operate at the outset or later in the cycle. Whether it is desired that the pump 54 operates simultaneously with the drum 10, or at different times in the cycle, rotation of the drum 10 in a given direction always results in the pump 54 moving in a particular direction because they are effectively being driven from the same shaft.
• the brake 126 serves primarily to hold the shaft 122 in a desired position and to prevent it from rotating as might be the case if some extraneous force were to tension the cables. From the foregoing it will be recognized that the above described drive system has numerous advantages in that it is very economical of space, is efficient in the use of energy, has much simplified hydraulic lines as compared with the earlier system described above, and as a result is more reliable.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Fluid-Pressure Circuits (AREA)
• Soil Working Implements (AREA)
• Storing, Repeated Paying-Out, And Re-Storing Of Elongated Articles (AREA)
• Electric Cable Installation (AREA)
• Hydraulic Motors (AREA)

Applications Claiming Priority (2)

Publications (2)

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ID=23787194

Family Applications (1)

Country Status (5)

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• 1990
  • 1990-11-07 JP JP3501453A patent/JPH05502428A/ja active Pending
  • 1990-11-07 WO PCT/US1990/006454 patent/WO1991008976A1/en active IP Right Grant
  • 1990-11-07 CA CA002069494A patent/CA2069494C/en not_active Expired - Fee Related
  • 1990-11-07 DE DE69007492T patent/DE69007492T2/de not_active Expired - Fee Related
  • 1990-11-07 EP EP91901086A patent/EP0505437B1/de not_active Expired - Lifetime

Non-Patent Citations (1)

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