JP2014047057A - Electrically-driven type lift device, and forklift using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a load to a lift device, by absorbing and cushioning impact force added to a conversion driver fitted to a screw shaft and making rotational-linear motion.SOLUTION: An electrically-driven type lift device 23 comprises a roller gauge 32 out-fitted to a screw shaft 31 for a lift by rotatingly driving the screw shaft 31 for the lift arranged along a lifting guide member 23A by an electric motor 34 for the lift, and can liftably drive a cargo handling fork 16 along the lifting guide member 23A by the roller gauge 32, and is provided with a driving plate 54 supported by the roller gauge 32 and a shock absorber 51 for absorbing a downward shock added to a passive plate 55 from the cargo handling fork 16 by a lower cushioning spring 58D by absorbing upward impact force added to the driving plate 54 via the roller gauge 32 from the screw shaft 31 for the lift by an upper cushioning spring 58U in a connection part 50 of the passive plate 55 interlocked with-connected to the cargo handling fork 16.

Description

  The present invention relates to an electric lift device including a rotation-linear motion conversion mechanism provided with a screw shaft and a roller gauge, and a forklift using the electric lift device.

  For example, in a conventional electric forklift, a hydraulic pump is driven by an electric motor to generate a hydraulic pressure, and this hydraulic pressure is used as a drive source of the lift device, and the hydraulic pressure is sent to a hydraulic cylinder to drive the lifting / lowering fork.

  However, from the viewpoint of promoting effective use of energy in recent years, for example, Patent Document 1 and Patent Document 2 propose using an electric actuator (rotation-linear motion conversion mechanism) from a hydraulic actuator.

  In Patent Document 1, a linear actuator, which is an electric actuator, is provided with a roller gauge (conversion drive body) having two pairs of upper and lower rollers in the circumferential direction, each rolling two flanks facing each other with a screw shaft. doing. Patent Document 2 proposes to provide a contact force equalizing mechanism for preventing an unbalanced load applied to the screw shaft from a cargo handling fork via a roller gauge.

  In addition, the lift device in Patent Document 1 and Patent Document 2 arranges the outer frame and the inner frame so that they can be raised and lowered, and arranges the carriage that supports the cargo handling fork on the inner frame so that they can be raised and lowered. A double speed mechanism comprising a winding transmission mechanism in which a chain connecting an outer frame and a carriage is wound around a sprocket wheel provided on the upper portion of the inner frame is employed. Then, the roller gauge and the inner frame are connected, and the screw shaft of the linear actuator is rotationally driven, whereby the inner frame can be driven up and down, and the carriage can be moved up and down at a double speed via the sprocket wheel.

WO2010 / 150732A1 (FIG. 12) JP2011-69449A (FIG. 12)

  By the way, in the above conventional structure, when the vehicle gets over the road surface step in the loaded state, an upward and downward impact force is generated on the roller gauge. Further, when the screw shaft is rotated to raise the roller gauge and lift the cargo handling fork loaded with a load, an upward impact force is generated on the roller gauge. Further, when the screw shaft is rotated to raise the roller gauge and the landed load is lifted by the handling fork, a downward impact force is generated on the roller gauge. These impact forces may impose a load on the roller cage or screw shaft and shorten its life.

  The present invention solves the above-described problems, absorbs and cushions the impact force applied to the conversion drive body that rotates and linearly moves, and reduces the load on the lift device and the electric lift device. An object of the present invention is to provide a forklift using a lift device.

The electric lift device according to claim 1 is:
A lift screw shaft disposed along the lifting guide member, a lift electric motor that rotationally drives the lift screw shaft, and a conversion drive body that is externally fitted to the lift screw shaft and driven to move up and down. An electric lift device capable of driving the cargo handling member up and down along the lifting guide member by the conversion driving body,
A drive member supported by the conversion drive body, a passive member interlocked with the cargo handling member, and a connecting portion that connects the drive member and the passive member are provided from the lift screw shaft via the conversion drive body. A shock absorber capable of buffering an upward impact force applied to the driving member and a downward impact applied to the passive member from the cargo handling member is provided.

The electric lift device according to claim 2 is:
An outer frame that is erected, an inner frame that is guided so as to be movable up and down along the outer frame, a lifting and lowering body that is guided so as to be movable up and down along the inner frame and that is provided with a cargo handling member, and one end of which is the outer frame And a winding transmission mechanism having a cable body connected to the lifting and lowering body and the other end connected to the elevating and moving body and a turning ring body wound around an intermediate portion of the cable body provided on the inner frame. A lift screw shaft disposed along the outer frame, a lift electric motor that rotationally drives the lift screw shaft, a conversion drive body that is externally fitted to the lift screw shaft and is driven up and down, An electric lift device comprising:
An upward impact force applied to the drive member from the screw shaft for lift through the conversion drive body to the connecting portion of the drive member supported by the conversion drive body and the passive member attached to the inner frame, and a cargo handling member Are provided with shock absorbers capable of buffering the downward impact force applied to the passive member via the lifting and lowering moving body, the winding transmission mechanism and the inner frame.

The electric lift device according to claim 3 is the configuration according to claim 1 or 2,
The shock absorber is
The upper drive member and the lower passive member are arranged in contact with each other so as to be separated from each other, and an upper elastic member that urges the drive member toward the passive member, and urges the passive member toward the drive member. A lower elastic member is provided.

The forklift according to claim 4 is:
An outer frame erected on the traveling body, an inner frame guided so as to be movable up and down along the outer frame, a carriage provided so as to be movable up and down along the inner frame and provided with a cargo fork, and one end of the carriage A winding transmission mechanism having a lifting chain connected to the outer frame and having the other end connected to the carriage and a turning ring provided on the inner frame and winding an intermediate portion of the lifting chain. A lift screw shaft erected along the outer frame, a lift electric motor that rotationally drives the lift screw shaft, and a conversion drive body that is externally fitted to the lift screw shaft and driven to move up and down A forklift equipped with an electric lift device comprising:
An upper portion that is applied to the drive member from the lift screw shaft via the conversion drive member to a connecting portion that connects the upper drive member supported by the conversion drive member and the lower passive member attached to the inner frame. And a shock absorbing device capable of buffering the impact force applied to the passive member from the cargo handling fork via the electric lift device.

The forklift according to claim 5 is the configuration according to claim 4,
The shock absorber is
The upper drive member and the lower passive member are arranged in contact with each other so as to be separated from each other, and an upper elastic member that urges the drive member toward the passive member, and urges the passive member toward the drive member. A lower elastic portion is provided.

The forklift according to claim 6 is the configuration according to claim 4,
The shock absorber is
The upper drive member and the lower passive member are arranged so as to be in contact with each other and can be separated from each other, and a through-hole communicating with each other is formed in the drive member and the passive member,
While providing an upper end restriction portion at the upper end portion of the restriction shaft loosely fitted in the through hole, a lower end restriction portion is provided at the lower end portion,
An upper elastic member that is externally fitted to the restriction shaft is interposed between the upper restriction portion and the drive member, and a lower portion that is externally fitted to the restriction shaft between the restriction portion and the passive member. An elastic member is interposed.

  According to the first aspect of the present invention, the lift screw shaft is rotationally driven by the lift electric motor, and the cargo handling member is raised by the conversion drive member via the drive member and the passive member. When the cargo handling member that supports the load is activated and raised, an upward impact force is generated in the drive member and the conversion drive body due to the load of the load and the cargo handling member, but this impact force is absorbed by the shock absorber. And can be effectively buffered. Further, when the cargo handling member is raised to lift the landed load, a downward impact force is generated on the passive member due to the load of the cargo and the cargo handling member. This shock force can be absorbed and effectively buffered by the shock absorber. Since the impact force due to loading can be buffered in this way, it is possible to prevent wear, deformation, and damage of the conversion drive body and the lift screw shaft. Further, even when the cargo handling member is supported in a cantilevered manner and a biased impact force is applied, the effect of preventing wear, deformation, and damage is high. Further, since the shock absorber is not interposed in the lift screw shaft, the lifting stroke of the lift screw shaft is not reduced.

  According to the second aspect of the invention, the lift electric motor is activated to rotationally drive the lift screw shaft, and the inner frame is moved up and down by the conversion drive member via the drive member and the passive member, so that the winding transmission mechanism is The lifting / lowering moving body and the cargo handling member are lifted through. When the cargo handling member that supports the load is activated and raised, an upward impact force is generated in the drive member and the conversion drive body due to the load of the load and the cargo handling member, but this impact force is absorbed by the shock absorber. And can be effectively buffered. Furthermore, when the cargo handling member is lifted and the landed load is lifted, a downward impact force is generated on the passive member due to the load of the load and the cargo handling member, but the impact force is effectively absorbed by the shock absorber. Can be buffered. Since the impact force can be buffered in this way, it is possible to prevent wear, deformation, and damage of the conversion driver and the lift screw shaft. Further, even when the cargo handling member is supported in a cantilever manner and a biased impact force is applied to the conversion drive body, the effect of preventing wear, deformation, and damage is high. Further, since the shock absorber is not interposed in the lift screw shaft, the lifting stroke of the lift screw shaft is not reduced.

  According to the third aspect of the present invention, the upward impact force to the drive member that is separated from the passive member is absorbed by the upper elastic member being compressed, and the downward impact to the passive member that is separated from the drive member is performed. The impact force can be absorbed by the compression of the lower elastic member, and the impact force applied to the drive member and the passive member can be effectively buffered.

  According to the fourth aspect of the present invention, the lift electric motor is activated to rotationally drive the lift screw shaft, and the inner frame is moved up and down through the drive member and the passive member by the conversion drive body, so that the winding transmission mechanism is The carriage and the cargo handling fork are moved up and down. Further, when the load handling member that supports the load is raised or when the vehicle climbs over a step during traveling, an upward impact force is generated from the conversion drive body to the drive member due to the load of the load and the load handling member. This impact force is absorbed by the shock absorber and can be effectively buffered. In addition, the lifting screw shaft is driven to rotate to raise the cargo handling member, and when the landing load is lifted or over a level difference during traveling, the load of the cargo and the cargo handling member causes a downward impact force on the passive member. Occur. This impact force is absorbed by the shock absorber and can be effectively buffered. Since the impact force generated during lift driving or traveling can be buffered in this way, it is possible to prevent wear, deformation, and damage to the conversion drive body and the lift screw shaft. Further, even when the cargo handling member is supported in a cantilever manner and a biased impact force is applied to the conversion drive body, the effect of preventing wear, deformation, and damage is high. Further, since the shock absorber is not interposed in the lift screw shaft, the lifting stroke of the lift screw shaft is not reduced.

  According to the fifth aspect of the present invention, the impact force in the direction in which the driving member is separated upward from the passive member is absorbed by the upper elastic member being compressed, and the passive member is in the direction in which the passive member is separated downward from the driving member. The impact force is absorbed by the lower elastic member being compressed. Thereby, the impact force applied to the drive member and the passive member can be effectively buffered.

  According to the sixth aspect of the invention, the upper elastic member that presses the drive member toward the passive member side and the lower elastic member that presses the passive member toward the drive member side are restricted by the restriction shaft loosely fitted in the through hole. Since it is provided, the upper elastic member and the lower elastic member can be stably supported, and the upward impact applied to the drive member and the downward impact applied to the passive member can be effectively absorbed and buffered. Can protect the lift device.

1 is a rear perspective view of a cargo handling device according to a first embodiment of a reach-type forklift equipped with an electric lift device according to the present invention. It is a whole side view showing a reach type forklift. (A)-(c) shows an electric lift device, (a) is a partial sectional view in rear view, (b) is an enlarged vertical sectional view of an upper deflection absorbing portion, and (c) is a lower deflection absorbing portion. It is an enlarged vertical sectional view. It is sectional drawing of planar view of an electric lift apparatus. It is a top view of an electric lift device. It is a perspective view which shows a contact force equalization member. It is a longitudinal cross-sectional view which shows a roller gauge. (A) and (b) show the simple movable lifter carrying an electric lift device, (a) is a side view, and (b) is a back view. (A) and (b) show the modification of a buffer, (a) is a front view and (b) is a side view.

[Example 1]
Hereinafter, an embodiment of a reach forklift equipped with an electric lift device according to the present invention will be described with reference to FIGS.

  As shown in FIG. 2, the reach forklift includes a vehicle body (traveling body) 11 having a driver's seat 17 and a head guard 18, and a drive wheel 12 disposed on the left side at the bottom of the vehicle body 11 and a right side. The caster wheel 13 is disposed at a portion and is rotatable, and the left and right trail wheels 15 are rotatably supported by a pair of left and right outriggers 14 extending forward from the vehicle body 11. 11 is driven and steered. Further, a cargo handling device 21 having a lift device 23 according to the present invention is disposed between the outriggers 14 so as to be freely retractable, and a cargo handling fork (a cargo handling member) 16 is provided in the cargo handling device 21.

  As shown in FIG. 1, the cargo handling device 21 includes a base portion 22 and a lift device 23 erected on the base portion 22, and is formed on the inner surface of the outrigger 14 on the base portion 22. A pair of left and right front and rear wheels 22a guided by the guide rail 14a are rotatably supported. The vehicle body 11 is provided with an electric reach jack (not shown) for moving the cargo handling device 21 in and out of the predetermined range along the outrigger 14.

As shown in FIGS. 3 to 5, the lift device 23 includes a lift guide member 23 </ b> A and a lift drive unit 23 </ b> B. The elevating guide member 23A is an inner frame which is guided up and down freely through a gate-shaped outer frame 24 standing on the base 22 and a plurality of inner frame guide rollers 26A and 26B in a post portion of the outer frame 24. A frame 25 and a carriage (lifting / lowering body) 27 guided in a freely moving manner through a carriage guide roller 27A are provided in a post portion of the inner frame 25. The lift drive unit 23 </ b> B is connected to a turning sprocket wheel 29 provided on the upper portion of the inner frame 25, one end connected to a chain connecting unit (connecting unit) 24 a attached to the outer frame 24, and the other end connected to a chain bracket of the carriage 27. A winding type transmission mechanism 30 having a lift chain (cord) 28 connected to the (connecting portion) 27a is provided. Reference numeral 29a denotes a cable sheave for sending drive power to the carriage 27 side. In this winding transmission mechanism 30, the lift chain 28 is wound around the turning sprocket wheel (turning wheel body) 29, so that the stroke (or speed) is twice as high as the lifting stroke of the inner frame 25. Thus, a double speed mechanism for raising and lowering the carriage 27 is configured.
Also, a lift screw shaft 31 disposed along the rear portion of the post portion of the outer frame 24, and a plurality of (for example, circumferentially equiangular angles) that are externally fitted to the lift screw shaft 31 and roll on the flank surface. A roller gauge (conversion drive body) 32 that is a rotation-linear motion conversion drive body having three rollers (two sets in the upper and lower pairs), and a speed reducer 34a that rotationally drives the lift screw shaft 31 via a gear mechanism 33. And an electric motor 34 for lifting. Further, in order to cope with the uneven load caused by the cargo handling fork 16, contact force equalizing members 35 fitted on the lift screw shafts 31 on the left and right roller gauges 32 are respectively arranged, and the left and right contact force equalization is provided. A drive beam material 36 is stretched over the activating member 35. The drive beam member 36 is formed with U-shaped cutouts 36a that are respectively opened at the left and right edges, and is loosely fitted to the lift screw shaft 31 in the cutouts 36a, so that the contact force equalizing member 35 is formed. It is placed on top.

  As shown in FIG. 7, in the roller gauge 32, three support rollers 32a that rotatably support the lower flank surface with respect to a load from above are arranged on the gauge body 32c at every predetermined angle. The three guide rollers 32b that rotatably support the flank surface are arranged at fixed angles.

  In addition, as shown in FIG. 8, the contact force equalizing member 35 is rotated by a lower sliding member 35b having a semicircular cross section through a recess in a direction perpendicular to the axis and orthogonal to the bottom surface of the intermediate ring body 35a. Arranged freely. Further, on the top surface of the intermediate ring body 35a, an upper sliding member 35c having a semicircular cross section is rotatably disposed via a recess at a symmetrical position substantially perpendicular to the axis and intersecting the lower sliding member 35b.

  Further, in order to absorb the deflection of the lift screw shaft 31 due to the unbalanced load generated for cantilever support of the cargo handling fork 16, as shown in FIG. An upper deflection absorbing portion 37 is provided, and a lower deflection absorbing portion 39 is provided at the lower end portion of the lift screw shaft 31.

  As shown in FIG. 3 (b), the upper deflection absorbing portion 37 has a pair of left and right shaft support members 24 b attached to both sides of a connecting member 42 that connects the upper ends of the outer frame 24. A support hole 24c into which the upper end of the lift screw shaft 31 is fitted is formed in the shaft support member 24b, and a thrust bearing 38 with a centering washer is attached on the shaft support member 24b. The thrust bearing 38 is configured such that a lower bearing portion 38b of a bearing body 38a and a centering washer 38c are slidably overlapped via a spherical surface portion, and an upper end portion of the lift screw shaft 31 is located above the bearing body 38a. It is fixed to the bearing portion 38d via a screw mechanism 38e. Therefore, the thrust bearing 38 with the aligning washer allows tilting at the upper end of the lift screw shaft 31 within a predetermined range, and can absorb the bending of the lift screw shaft 31 in the circumferential direction. Reference numeral 43 denotes a cover body that covers the upper deflection absorbing portion 37.

  As shown in FIG. 3C, the lower deflection absorbing portion 39 is provided with a drive shaft 40 driven through a gear mechanism 33 on the output shaft of a lift electric motor 34 driven through a speed reducer. The drive yoke 41 a provided on the drive shaft 40 and the passive yoke 41 b provided on the lower end of the lift screw shaft 31 are arranged on a plane perpendicular to the axis of the lift screw shaft 31. And a universal joint 41 connected through cross pins 41c and 41d orthogonal to each other.

  On the other hand, as shown in FIGS. 3 and 4, the passive beam material 52 is connected between the lower portions of the left and right posts of the inner frame 25, and the passive beam material 52 and the drive beam material 36 include the buffer device 51. The connecting portion 50 is interlocked and connected.

  As shown in FIG. 3A, the shock absorber 51 has the driving beam material 36 disposed at the upper level and the passive beam material 52 disposed at the lower level. A pair of left and right connecting cylinders 53 are suspended from the lower surface of the driving beam member 36 at a predetermined interval, and a driving plate (driving member) 54 is attached to the bottom of the connecting cylinders 53. A pair of left and right passive plates (passive members) 55 facing the lower side of the left and right drive plates 54 are supported by the support members and protrude from the rear portion of the passive beam member 52 so that the drive plates 54 and the passive plates 55 are in contact with each other. Be placed. Further, through holes 56 are formed in the drive plate 54 and the passive plate 55 so as to communicate with each other, and the regulation shafts 57 are loosely fitted in the through holes 56, respectively. The restriction shaft 57 is attached with an upper flange portion (restriction portion) 57U which is bolted to the upper end portion, and an upper buffer spring (upper buffer spring) composed of a plurality of disc springs between the upper flange portion 57U and the drive plate 54. Member) 58U is externally fitted to the restriction shaft 57 and interposed. The restriction shaft 57 is provided with a lower flange part (restriction part) 57D which is bolted to the lower end part, and a lower buffer spring (buffer member) comprising a plurality of disc springs between the lower flange part 57D and the passive plate 55. 58D is externally fitted to the restriction shaft 57 and interposed. Reference numeral 59 denotes a cover cylinder that is suspended downward from the passive plate 55 and covers the lower buffer spring (lower buffer member) 58D.

  In the above configuration, the lift electric motor 34 is activated to rotate the lift screw shaft 31, and the drive plate 54 is raised via the roller gauge 32. And the passive plate 55 is driven by the drive plate 54 via the connection part 50 which has the buffer device 51, and the inner frame 25 is raised. Further, the carriage 27 is raised via the winding transmission mechanism 30 and the cargo handling fork 16 is lifted.

  When a load is placed on the cargo handling fork 16, when the cargo loading fork 16 is started upward, the drive plate 54 is lifted by the lift screw shaft 31 via the roller gauge 32. Then, an upward impact force is generated on the drive plate 54 between the load loaded fork 16 and the passive plate 55 to which the load is applied, and is transmitted to the roller gauge 32. However, the upward impact force applied to the drive plate 54 is absorbed and buffered by the action of the upper buffer spring 58U.

  Further, when the landed load is lifted by the cargo handling fork 16, a downward impact force is applied to the passive plate 55 from the cargo handling fork 16 via the winding transmission mechanism 30 to the drive plate 54 to be lifted. Occur. However, the upward impact force applied to the drive plate 54 is absorbed and buffered by the action of the upper buffer spring 58U.

As a result, the impact on the peripheral members including the roller gauge 32 can be reduced to effectively prevent wear, deformation, and breakage, thereby extending the life of the lift device.
In addition, the cargo fork 16 is cantilevered by the carriage 27, and an offset load is applied to the passive plate 55 via the inner frame 25 and the connecting member 42, but the passive plate 55 and the drive plate 54 are separated from each other. It is not fixed, and is merely pressed against each other by the upper and lower buffer springs 58U and 58D, and is loosely fitted into the through hole 56 from the restriction shaft 57, so that the displacement of the passive plate 55 can be allowed, and the roller Uneven load applied to the gauge 32 can be greatly reduced.

  Here, three sets of disc springs are used for the upper buffer spring 58U, and two sets of disc springs are used for the lower buffer spring 58D, and the elasticity of the lower buffer spring 58D is used. The reason why the elastic force of the upper buffer spring 58U is made larger than the force is that the downward vibration and impact force applied from the drive plate (drive plate) 54 to the passive plate (conversion drive body) 55 when climbing over the step during loading travel. This is because [or the impact force applied downward from the passive plate (conversion drive body) 55 to the drive plate (drive plate) 54] is larger than the vibration or impact force generated in the opposite direction.

  According to the first embodiment, an upward impact force is generated from the roller gauge 32 to the drive plate 54 due to the load and the load of the cargo handling fork 16 at the time of starting up the cargo handling fork 16 on which the load is supported. This impact force can be absorbed by the upper buffer spring 58U of the shock absorber 51 and effectively buffered. Further, when the lifting screw shaft 31 is rotationally driven to raise the cargo handling fork 16 and lift the landed load, a downward impact force is generated on the passive plate 55 by the load of the cargo and the cargo handling fork 16. . This impact force can be absorbed by the shock absorber 51 and effectively buffered. Further, when the vehicle passes over the road surface level while traveling on the loading fork 16, vertical vibration and impact force are generated on the passive plate 55. These vibrations and impact forces can be absorbed by the shock absorber 51 and effectively buffered. As described above, since vibration and impact force during running can be buffered, wear, deformation, and damage of the roller gauge 32 and the lift screw shaft 31 can be prevented. Further, since the shock absorber is not interposed in the lift screw shaft, the lifting stroke of the lift screw shaft is not reduced.

  Further, since the drive plate 54 and the passive plate 55 that are in contact with each other are urged in the direction in which they are pressed against each other by the upper and lower buffer springs 58U and 58D, the upward impact applied to the drive plate 54 and the downward impact applied to the passive plate 55 And can absorb the vibration and effectively buffer it. Further, even if the cargo handling fork 16 is supported in a cantilevered manner and displaced to the passive plate 55, it is possible to prevent a biased impact force from being transmitted from the drive plate 54 to the roller gauge 32, thereby preventing wear and tear. Highly effective in preventing deformation and damage.

Although the reach type electric forklift has been described in the first embodiment, a counterweight type forklift may be used.
[Example 2]
Second Embodiment A simplified movable lifter equipped with an electric lift device according to the present invention will be described with reference to FIG. Note that the same members as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. Moreover, although the electric lift device is provided in the vehicle body 11 or the moving body 61, it can be attached to a fixed base.

  A pair of left and right outriggers 14 project forward from a self-propelled or manual moving body 61 having traveling wheels 62, and trail wheels 15 are rotatably supported by the outriggers 14, respectively. A guide frame 63 for the gate is erected on the moving body 61, and a carriage (elevating moving body) 64 can be raised and lowered via a guide roller 64a between elevating rails formed on the inner surface of the post portion 63a of the guide frame 63. It is guided to. A pair of left and right cargo handling forks (a cargo handling member) 16 as a cargo handling tool is attached in front of the carriage 64.

  The electric lift device 60 provided on the back surface of the guide frame 63 is different from that of the first embodiment in that the lift screw shaft 31 is one and the double speed mechanism including the winding transmission mechanism 30 is not provided. This is different from the lift device 23. That is, a lift screw shaft 31 that is rotationally driven by the lift electric motor 34 via the gear mechanism 33 is erected and arranged substantially at the center of the back surface of the guide frame 63. The contact force equalizing member 35 is fitted, and an upper deflection absorbing portion 37 is interposed at the upper end portion thereof, and a lower deflection absorbing portion 39 is interposed at the lower end portion thereof.

  Further, the carriage 64 is guided to the guide frame 63 by a guide rail formed on the inner surface of the post portion 63a through a guide roller 64a so as to be movable up and down. Although a pair of left and right cargo handling forks 16 is attached to the carriage 64, the cargo handling member may be, for example, an exit / retreat table.

  A drive beam member 36 having a hole portion in which the lift screw shaft 31 is loosely fitted is installed on the upper part of the contact force equalizing member 35, and a drive plate 54 is attached via a pair of left and right connecting cylinders 53. Yes. A pair of left and right shock absorbers 51 similar to those of the first embodiment are provided at the passive plate 55 protruding rearward from the carriage 27 and the connecting portion 50 of the drive plate 54.

As described above, according to the electric lift device 60 of the second embodiment, the same effect as that of the first embodiment can be obtained, and even if the double speed mechanism is not employed, the same applies. Can do.
[Modification of shock absorber]
A modification of the shock absorber 51 will be described with reference to FIG. That is, the shock absorber 70 includes a driving plate 71 protruding from the driving beam member 36 and disposed at the upper portion, and a passive plate 72 protruding from the passive beam member 52 and disposed in contact with the lower portion of the driving plate 71. Guide grooves 71C and 75C are formed at the four corners. Then, guide rods 71R extending in opposite directions via guide grooves 72C and 71C are attached to the four corner positions of the drive plate 71 and the passive plate 72, and the bottom regulating plate 71D and the ceiling are attached to the ends of the guide rods 71R and 72R. The part regulating plate 72D is attached, and thereby, the driving plate 71 and the passive plate 72 are arranged so as to be able to approach and separate. Further, an upper coil spring (upper buffer member) 73U that urges the drive plate 71 toward the passive plate 72 is interposed between the drive plate 71 and the top restricting plate 72U, and the passive plate 72 and the bottom restricting plate 71D are interposed. A lower coil spring (lower buffer member) 73D for biasing the passive plate 72 toward the drive plate 71 is interposed therebetween. As a result, an upward impact applied to the drive plate 71 can be absorbed, and a downward impact applied to the passive plate 72 can be absorbed.

  In the first embodiment, the electric lift device mounted on the stacker crane has been described. However, the present invention can also be applied to a stacker crane, a picking device, and the like equipped with the electric lift device.

16 fork 21 for cargo handling cargo handling device 23 lift device 23A lift guide member 23B lift drive unit 24 outer frame 25 inner frame 27 carriage (lifting and moving body)
30 Winding type transmission mechanism 31 Screw shaft for lift 32 Roller gauge (conversion drive)
34 Lifting electric motor 35 Contact force equalizing member 36 Driving beam material 37 Upper deflection absorbing portion 38 Thrust bearing with aligning washer 39 Lower deflection absorbing portion 40 Driving shaft 50 Connecting portion 51 Buffer device 52 Passive beam material 53 Connecting cylinder 54 Drive plate (drive member)
55 Passive plate (passive member)
56 Through hole 57 Restriction shaft 57U Upper collar part (upper end restriction part)
57D Lower collar part (lower end regulating part)
58U Upper buffer spring (Upper elastic member)
58D Lower shock absorber spring (upper elastic member)
60 Lifting device 61 Moving body 63 Guide frame 64 Carriage (lifting / lowering moving body)
70 shock absorber 71 drive plate 71U bottom restricting plate 72 passive plate 72D top restricting plate 73U upper coil spring (upper shock absorbing member)
73D Lower coil spring (lower shock absorber)

Claims (6)

A lift screw shaft disposed along the lifting guide member, a lift electric motor that rotationally drives the lift screw shaft, and a conversion drive body that is externally fitted to the lift screw shaft and driven to move up and down. An electric lift device capable of driving the cargo handling member up and down along the lifting guide member by the conversion driving body,
A drive member supported by the conversion drive body, a passive member interlocked with the cargo handling member, and a connecting portion that connects the drive member and the passive member are provided from the lift screw shaft via the conversion drive body. An electric lift device comprising: a shock absorber capable of buffering an upward impact force applied to the drive member and a downward impact applied from the cargo handling member to the passive member. An outer frame that is erected, an inner frame that is guided so as to be movable up and down along the outer frame, a lifting and lowering body that is guided so as to be movable up and down along the inner frame and that is provided with a cargo handling member, and one end of which is the outer frame And a winding transmission mechanism having a cable body connected to the lifting and lowering body and the other end connected to the elevating and moving body and a turning ring body wound around an intermediate portion of the cable body provided on the inner frame. A lift screw shaft disposed along the outer frame, a lift electric motor that rotationally drives the lift screw shaft, a conversion drive body that is externally fitted to the lift screw shaft and is driven up and down, An electric lift device comprising:
An upward impact force applied to the drive member from the screw shaft for lift through the conversion drive body to the connecting portion of the drive member supported by the conversion drive body and the passive member attached to the inner frame, and a cargo handling member An electric lift device characterized in that a shock absorber capable of buffering a downward impact force applied to the passive member via an elevating moving body, a winding transmission mechanism and an inner frame is provided. The shock absorber is
The upper drive member and the lower passive member are arranged in contact with each other so as to be separated from each other, and an upper elastic member that urges the drive member toward the passive member, and urges the passive member toward the drive member. The electric lift device according to claim 1, wherein a lower elastic member is provided. An outer frame erected on the traveling body, an inner frame guided so as to be movable up and down along the outer frame, a carriage provided so as to be movable up and down along the inner frame and provided with a cargo fork, and one end of the carriage A winding transmission mechanism having a lifting chain connected to the outer frame and having the other end connected to the carriage and a turning ring provided on the inner frame and winding an intermediate portion of the lifting chain. A lift screw shaft erected along the outer frame, a lift electric motor that rotationally drives the lift screw shaft, and a conversion drive body that is externally fitted to the lift screw shaft and driven to move up and down A forklift equipped with an electric lift device comprising:
An upper portion that is applied to the drive member from the lift screw shaft via the conversion drive member to a connecting portion that connects the upper drive member supported by the conversion drive member and the lower passive member attached to the inner frame. A forklift characterized in that a shock absorber capable of buffering the impact force on the lower side and the downward impact force applied to the passive member from the cargo handling fork via the electric lift device is provided. The shock absorber is
The upper drive member and the lower passive member are arranged in contact with each other so as to be separated from each other, and an upper elastic member that urges the drive member toward the passive member, and urges the passive member toward the drive member. The forklift according to claim 4, further comprising a lower elastic portion. The shock absorber is
The upper drive member and the lower passive member are arranged so as to be in contact with each other and can be separated from each other, and a through-hole communicating with each other is formed in the drive member and the passive member,
While providing an upper end restriction portion at the upper end portion of the restriction shaft loosely fitted in the through hole, a lower end restriction portion is provided at the lower end portion,
An upper elastic member that is externally fitted to the restriction shaft is interposed between the upper restriction portion and the drive member, and a lower portion that is externally fitted to the restriction shaft between the restriction portion and the passive member. The forklift according to claim 4, wherein an elastic member is interposed.

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