JP2018070361A - Electrically raising/lowering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrically raising/lowering device that facilitates a moving operation for raising/lowering an article.SOLUTION: An electrically raising/lowering device comprises: a placing table part 21 on which an article is placed; a raising/lowering actuation part 5 in which one end of an engagement chain 4 is connected to the placing table part 21; a motor part 6 that transmits power to the raising/lowering actuation part 5; a raising/lowering support part 20 supporting and fixing the raising/lowering actuation part 5; weight detecting means 15a to 15d that detect a weight applied to the placing table part 21 and outputs a weight signal; position detecting means 19 that detects a vertical position of the placing table part 21 and outputs a position signal; and a control part 10 that instructs the motor part 6 so that the placing table part 21 is balanced in an arbitrary position in response to a position signal from the position detecting means 19 and a weight signal from the weight detecting means 15a to 15d.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electric lifting apparatus that is used for manufacturing assembly equipment in the manufacturing field, transfer equipment in the transportation field, and the like, and moves up and down by a motor or the like in the vertical vertical direction while maintaining the posture of the article in parallel.

  Conventionally, as an elevating device, there is an elevating device that moves an article such as a heavy object up and down using a pair of meshing chains that mesh with each other and are driven integrally. Such a lifting device using a meshing chain is a mechanism that supports the article in the vertical direction and lifts and lowers using the stiffening of the meshing chains by meshing with each other. The lifting device is an electric system, and is composed of a lifting / lowering operation unit that stores a meshing chain and a sprocket that performs a feeding operation thereof, a motor and a speed reducer that drives the lifting / lowering operation unit, and an electric circuit that drives the motor. It was.

JP 2012-001360 A JP 2016-117420 A

  However, as described in Patent Document 1 and Patent Document 2, the above-described electric lifting device simply moves the article placed on the pedestal portion electrically by an operation switch or the like. Therefore, it has been difficult to move the article to a desired position in precise assembly. That is, since the raising / lowering operation is performed by the operation switch while visually observing the position of the article, it is not suitable for an operation of inserting the article vertically upward with a slight peripheral clearance from below, for example. This is because the raising / lowering operation by the operation switch does not control the force for inserting the article, and thus the article may be damaged by inserting it obliquely. Moreover, when transferring from the electric lifting device to the shelf or the conveyor by moving up and down, it is necessary to visually adjust the height of the transfer using an operation switch and to adjust it each time.

  In view of such a problem, an object of the present invention is to provide an electric lifting device that facilitates the lifting and lowering operation of an article.

In order to achieve the above object, the electric lifting device according to claim 1
A pedestal for placing items;
A lifting / lowering operation unit which includes a pair of meshing chains and connects one end of the meshing chain to the platform and raises / lowers the platform;
A motor unit that transmits power to the lifting and lowering unit;
Weight detection means for detecting the weight applied to the pedestal and outputting a weight signal;
Position detecting means for detecting a lift position of the pedestal unit and outputting a position signal;
And a control unit that commands the motor unit so that the pedestal unit is balanced at an arbitrary position from the position signal from the position detection unit and the weight signal from the weight detection unit.

  In order to achieve the above object, in the electric lifting device according to claim 2, the controller is further configured to apply a predetermined external force smaller than the load of the article to at least one of the table and the article. To keep the article in a balanced state and to apply an external force to at least one of the pedestal and the article less than a predetermined external force, it is possible to select the operation of raising or lowering the article at any time, and command the motor unit Is configured to do.

  In order to achieve the above object, in the electric lifting device according to claim 3, when the control unit further applies a force exceeding a predetermined weight in the vertical downward direction to the pedestal unit within a predetermined time. The pedestal unit is configured to perform control so as to perform a damped motion in the vertical direction.

  According to a fourth aspect of the present invention, in order to achieve the above-mentioned object, the weight detection means has a strain gauge and is configured to detect the weight applied to the pedestal.

  According to a fifth aspect of the present invention, in order to achieve the above object, the motor unit includes a wave gear reducer.

  According to a sixth aspect of the present invention, in order to achieve the above object, the pedestal includes a top plate that is movable in the horizontal direction and a fixing means that fixes the horizontal position of the top plate.

  According to a seventh aspect of the present invention, in order to achieve the above-described object, the weight detection means includes at least one of a pedestal portion, a lift support portion that supports the lift operation portion, a lift operation portion, and a motor portion. Is provided.

  In the electric lifting device according to the eighth aspect, in order to achieve the above object, a plurality of weight detecting means are arranged on the pedestal.

  In the electric lifting device according to the ninth aspect, in order to achieve the above object, a plurality of weight detecting means are arranged on the lifting support portion.

  According to the electric lifting device of the first aspect of the present invention, the control unit moves to the motor unit so that the pedestal unit is balanced at an arbitrary position by the weight signal from the weight detection unit and the position signal from the position detection unit. Since the command is given, the operator can touch the pedestal part or the article and can move the article up and down with a slight force.

  According to the electric lifting device of the invention described in claim 2, the balance is maintained in a state where a predetermined external force smaller than the load of the article is applied to at least one of the pedestal part and the article, and a small external force less than the predetermined external force is applied. At times, the item can be selected in either the upper or lower direction, and the article automatically moves. Therefore, the article is slightly shifted from the balance state, that is, it works to move the article by generating either a slight ascending force or a descending force, and the operator works while applying a slight force to the article to suppress this. Therefore, the article can be lifted and lowered comfortably, which is particularly useful for fine assembly work.

  According to the electric lifting device of the invention described in claim 3, in addition to the above-described effect, when the weight in the vertically downward direction of a predetermined value or more is applied within a predetermined time, the pedestal portion is attenuated in the vertical direction. Because it is controlled to move, an article that is heavier than a predetermined weight is dropped on the pedestal, or an operator falls down, and a vertical downward external force is applied to the article or the pedestal. Even when a large load change occurs within a short time, it is possible to prevent breakage of the lifting / lowering operation unit and the motor unit reduction gear of the electric lifting device.

  According to the electric lifting device of the invention described in claim 4, in addition to the above effect, the weight of the article is detected by the strain gauge, so that self-compensation characteristics against temperature change and creep deformation of the weight detection means are given. Therefore, it is possible to compensate for temperature changes and creep deformation without taking extra compensation means. Therefore, it is possible to provide an electric lifting apparatus that eliminates the influence of changes in the environment in which the electric lifting apparatus is used and creep deformation due to long-time handling of heavy objects.

  According to the electric lifting device of the invention described in claim 5, in addition to the above effect, since the motor unit includes a wave gear reducer at the output unit, there is no backlash. A non-controllable area can be eliminated and a smooth balance maintaining operation can be performed.

  According to the electric lifting device of the invention described in claim 6, in addition to the above-described effect, the pedestal unit has a top plate that is movable in the horizontal direction, so that articles placed on the top plate can be smoothly transferred to the outside. Can be moved and reprinted. Moreover, since the fixing means for fixing the horizontal position of the top plate is provided, the article can be fixed and held at an arbitrary position, and the work for handling the article is facilitated.

  According to the electric lifting device of the seventh aspect of the invention, in addition to the above effects, the degree of freedom of the arrangement position of the weight detection means is high, and the electric lifting device can be arranged according to the use environment of the electric lifting device. In addition, by arranging the weight detection means at a plurality of locations, it is possible to increase the accuracy of weight detection and to smoothly lift and lower the article.

  According to the electric lifting apparatus of the invention described in claim 8, in addition to the above-described effect, since the plurality of weight detecting means are arranged on the cradle part, it is not always necessary to place the article in the center part of the cradle part. , The degree of freedom of work for handling the article is increased.

According to the electric lifting device of the ninth aspect of the invention, in addition to the above effect, a plurality of weight detecting means are arranged on the lifting support portion, and therefore, the wiring to the control portion can be facilitated.

It is a lineblock diagram of the electric raising and lowering device concerning a 1st embodiment of the present invention. It is a detailed configuration diagram of the electric lifting device according to the first embodiment of the present invention. It is a state figure when the stand part of the electric lifting apparatus which concerns on the 1st Embodiment of this invention falls. It is a block diagram of the electric lifting apparatus which concerns on the 2nd Embodiment of this invention. It is a side view of the electric lifting apparatus which concerns on the 2nd Embodiment of this invention. It is a side view when the stand part of the electric lifting apparatus which concerns on the 2nd Embodiment of this invention moves. It is a block diagram of the electric lifting apparatus which concerns on the 3rd Embodiment of this invention.

Hereinafter, the electric lifting apparatus according to the first embodiment of the present invention will be described in detail based on the drawings. FIG. 1 is a configuration diagram of the electric lifting device according to the first embodiment of the present invention when an article is placed, and FIG. 2 is a configuration in which the article is removed from FIG. FIG. FIG. 3 is a state diagram when the pedestal 21 of the electric lifting device according to the first embodiment of the present invention is lowered.

  The electric lifting apparatus 1 according to the embodiment of the present invention includes a table 21 on which an article 50 is placed, a lifting operation unit 5 that enables the table 21 to be lifted, and a table 21 that is moved up and down. Arms 3a and 3b for guiding, a motor unit 6 for driving the raising / lowering operation unit 5, weight detecting means 15a to 15d for detecting the weight of the article 50 provided on the pedestal unit 21, and the article connected to the motor unit 6 The position detection means 19 which detects 50 raising / lowering positions, and the control part 10 which controls the raising / lowering operation | movement of the stand part 21 are provided. The electric lifting device 1 includes a carriage 2 with wheels, a handle grip 12 and an operation unit 13 in addition to these lifting units.

  On the lower surface side of the carriage 2, a plurality of free wheels that can freely change direction and a plurality of driven wheels that are fixed wheels that cannot change direction are provided. Therefore, the cart 2 can steer the electric lifting device 1 by pushing and pulling the handle grip 12.

  On the upper surface side of the carriage 2, an elevating operation unit 5 that allows the table 21 to be raised and lowered is fixed. The raising / lowering operation part 5 is a well-known thing which has the meshing chain 4, Comprising: It has a chain which can mutually mesh and makes a pair. The meshing chain 4 is housed in the case of the lifting / lowering operation unit 5 in a freely bendable state where the meshing is disengaged, and is driven upwardly in a state of meshing and stiffening by driving a driving source connected thereto. The part 21 is raised. More specifically, one end portion of the meshing chain 4 is connected and fixed to the support plate 18 with a bolt or the like, and the other end portion moves along a guide portion provided in the case of the lifting / lowering operation portion 5 and is stored as a free end. Yes. The meshing chain 4 is fed out by a sprocket in the case of the lifting / lowering operation unit 5, and the rotating shaft of the sprocket is connected to a motor unit 6 as a driving source via a coupling 8.

  The motor unit 6 is, for example, an AC servo motor to which a speed reducer 7 is attached, and a torque generated by the motor is amplified to a torque necessary for moving up and down the heavy article 50 by the speed reducer 7. In the embodiment of the present invention, the speed reducer 7 uses a wave gear speed reducer. The wave gear reducer has a wave generator with an elliptical outer periphery, and a large number of external teeth formed on the outer periphery, which are externally fitted to the wave generator so that the position bent in the circumferential direction is changed by the rotation of the wave generator. It is composed of a deformable flexspline and a circular spline having an inner tooth on the outer peripheral side of the flexspline and fitted to the outer teeth of the flexspline. The power is extracted and transmitted to a sprocket rotating shaft that connects the flexspline as a rotational output. It is desirable to reduce the backlash of the rotational power system as much as possible, and the backlash of the speed reducer affects the ascending / descending state of the elevating operation unit 5. Therefore, in the embodiment of the present invention, a wave gear speed reducer with extremely small backlash is used. Yes.

  Position detecting means 19 for detecting the rotational position of the motor is attached to the opposite side of the motor unit 6. In this embodiment, the position detecting means 19 is an encoder installed on the side opposite to the load of the motor unit 6. However, the position detecting unit 19 is provided on the sprocket in the case of the lifting / lowering operation unit 5 or the rotation shaft of the sprocket to position the feeding position of the meshing chain 4. It may be detected. It is also possible to provide the reducer 7 or the like. In this embodiment, an encoder based on optical reflection is used. However, the present invention is not limited to this, and an optical transmission type may be used, or a magnetic force may be used. Furthermore, the vertical position of the pedestal portion 21 may be detected by installing a reflective optical sensor or the like on the lifting support portion 20 and measuring the distance from the pedestal portion 21.

  The support plate 18 is guided by the X-shaped arms 3a and 3b in order to maintain the posture when the elevating operation unit 5 raises and lowers the placing table unit 21. The arm 3a and the arm 3b are provided opposite to each other with the lifting operation unit 5 interposed therebetween, and the lifting support unit 20 and the support plate 18 are provided with a support shaft for rotating the arm 3a and the arm 3b within a specified angle range, A slide mechanism that slides the ends of the arm 3a and the arm 3b is provided. FIG. 3 shows a state in which the cradle part 21 is positioned at the lowest point, and the arm 3a and the arm 3b shown in FIG. 3a and arm 3b are folded. The guide of the pedestal 21 is not limited to the above-described arm, but may be a hollow slide extendable multistage guide.

  The elevating support unit 20 supports the arm 3 a, the arm 3 b, and the elevating operation unit 5 and is placed on the carriage 2.

  The pedestal 21 is composed of a support plate 18 and a top plate 14, and the top plate 14 is installed on and supported by the support plate 18. Further, weight detection means 15 a to 15 d are arranged on the upper surface of the support plate 18 so as to be sandwiched between the top plate 14 and the weight detection means 15 a to 15 d. The weight detectors 15a to 15d are load cells having strain gauges, for example. The weight detection means 15a to 15d have a strain generating portion, and a strain gauge is attached to the strain generating portion, so that the strain applied to the strain generating portion can be detected. The strain gauge constitutes a Wheatstone bridge circuit and outputs an analog signal corresponding to the amount of strain. Further, the detected analog signal is amplified and calculated to obtain the weight applied to the top plate 14 and output it as a weight signal. Is. The weight signal is transmitted to the control unit 10 via a wiring cable (not shown). The wiring cable may be a spiral cord that expands and contracts, or may be fixed along the arms 3a and 3b.

  In the present embodiment, four weight detecting means are provided in the pedestal 21 but the present invention is not limited to this. By arranging a plurality of weight detection means, the degree of freedom of the position where the article 50 is placed on the top board 14 is increased, and the flexible work can be improved.

  The control unit 10 is fixed to the carriage 2 with a bracket or the like, and the weight detection means 15a to 15d are connected to the control unit 10 with a cable or the like.

  The motor driver 9 is fixed to the carriage 2 with a bracket or the like and has a circuit for driving the motor unit 6. The motor driver 9 is connected to the motor unit 6 and the control unit 10 by cables or the like.

  The power source 11 is fixed to the carriage 2 with a bracket or the like, and supplies power to the motor driver 9 and the control unit 10.

  The operation unit 13 is located on the handle unit of the carriage 2 and is connected to the control unit 10 with a cable or the like to perform switching of the operation mode or manual operation. The operation unit 13 may be detachable from the handle unit of the carriage 2 or may be wirelessly connected to the control unit 10.

  With this configuration, the control unit 10 receives weight signals from the weight detection units 15a to 15d provided on the pedestal unit 21, and receives position signals from the position detection unit 19 on the anti-load side of the motor unit 6, respectively. In addition, while maintaining the vertical position of the cradle 21, a command signal that cancels and balances the weight received by the cradle 21 is calculated and transmitted to the motor driver 9. The motor driver 9 drives the motor unit 6 based on this command, so that the article 50 placed on the table 21 is kept in a balanced state.

  In addition, the control unit 10 intentionally shifts the balance state described above to balance the article 50 when a predetermined external force smaller than the load of the article 50 is applied to at least one of the pedestal 21 and the article 50. It is also possible to keep the state. In addition, when applying external force to at least one of the pedestal 21 and the article 50 less than a predetermined external force, it is easy to select the operation of raising or lowering the article 50 at any time by instructing the control unit 10 from the operation unit 13. Is possible. Specifically, if the weight of the article 50 is 40 kg and the predetermined external force is set to 100 g vertically downward, the article 50 is lifted vertically with a force of 100 g, and the operator holds the article 50 vertically. If it is pressed downward with a force of 100 g, the position is maintained and balanced. On the other hand, if the weight of the article 50 is 40 kg and the predetermined external force is set to 500 g vertically upward, the article 50 descends vertically downward with a force of 500 g, and the operator supports the article 50 with a vertical upward force of 500 g. And keep that position and balance. Whether the predetermined external force is vertically upward or vertically downward is selected depending on the work to be performed, and this can be performed by the operator using a switch or the like of the operation unit 13 as needed.

  In addition, when the weight value obtained from the weight detection means 15a to 15d exceeds a predetermined weight within a predetermined time, the control unit 10 sets the position detected by the position detection means 19 at that time as the center point. Perform elastic viscosity control. At this time, the elastic force is obtained by multiplying the distance from the center point by the first coefficient, and the viscous force is obtained by multiplying the speed and the second coefficient. The sum of the load, the elastic force, and the viscous force of the article 50 is determined as a target value, and the control unit 10 calculates a command signal so that the weight value obtained from the weight detection means 15a to 15d matches this, and sends it to the motor driver 9. Send. Until the weight value and the speed are suppressed to a predetermined value or less, the control unit 10 updates the elastic force and the viscous force at regular intervals. Here, the first coefficient is a spring coefficient, and the second coefficient is a damping coefficient, which can be arbitrarily set by an operator who handles the electric lifting device 1. Therefore, when a large load change occurs in the vertically downward direction in the pedestal 21 within a relatively short predetermined time, the control unit 10 works so as to cause the pedestal 21 to be damped up and down. It is possible to prevent damage to the elevating operation unit 5 of the apparatus 1 and the speed reducer of the motor unit 6.

  4 is a configuration diagram of the electric lifting device according to the second embodiment of the present invention when the article 50 is placed, FIG. 5 is a side view thereof, and FIG. 6 is a diagram when the pedestal 21 is moved. It is a side view. Since the basic configuration is the same as that of the electric lifting device of the first embodiment, only the differences will be described.

  A rail (not shown) is provided on the support plate 18 of the table 21, and the movable side is fixed to the top plate 14. The rail is arranged so that the top plate 14 moves in the A direction, and the top plate 14 is movable in the A direction, that is, in the horizontal direction. The fixing means 22 fixes the top plate 14 to the support plate 18 and is, for example, a clamp lever or a slide lock that can be fixed / released by rotating the knob 90 times. In the second embodiment, the direction is the A direction, that is, one direction. However, the present invention is not limited to this, and the direction that is perpendicular to the A direction, the one that rotates about the approximate center of the top plate 14 and the combination thereof may be used. good. By this mechanism, for example, the article 50 placed on the top plate 14 can be smoothly moved and transferred to a shelf or a conveyor that cannot be accessed due to interference of the carriage 2. Further, since the fixing means 22 for fixing the horizontal position of the top plate 14 is provided, the article 50 can be fixed and held at an arbitrary position, and the work for handling the article is made safe and easy.

  Further, at this time, the weight detecting means may be provided on the pedestal 21 but is preferably installed on the elevating support portion 20 because the movable area of the top plate 14 may be limited. There are a plurality of weight detection means 15e to 15h between the lifting support portion 20 and the carriage 2 and are arranged in the same manner as the pedestal portion 21 of the first embodiment. In this case, in particular, since the entire center of gravity position including the article 50 and the table 21 can be detected, it can be notified as a warning that the center of gravity position is outside the controllable range. Moreover, since the weight detection means 15e-15h are in the fixed side in raising / lowering, there exists an advantage that wiring with the control part 10 becomes easy.

  FIG. 7 is a configuration diagram of an electric lifting apparatus according to a third embodiment of the present invention. Since the basic configuration is the same as that of the electric lifting device of the first embodiment, only the differences will be described.

  The weight detection means 17 with a speed reducer is disposed between the motor unit 6 and the coupling 8. Specifically, it is a torque detector for a rotating body integrated with a reduction gear. A strain gauge is attached to the strain generating portion provided on the output rotation shaft from the speed reducer so that the strain applied to the strain generating portion can be detected. The strain gauge constitutes a Wheatstone bridge circuit, amplifies an analog signal corresponding to the amount of strain, performs an operation to obtain a torque value, and outputs the weight received by the lifting / lowering operation unit 5 as a weight signal. .

  On the other hand, a strain generating portion may be provided on the sprocket shaft in the elevating operation portion 5 and a strain gauge may be attached to similarly obtain a torque value and output it as a weight signal.

  As mentioned above, although this invention was demonstrated based on preferable embodiment, this invention is not limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the summary.

  As an application example of the present invention, the present invention can be applied to an electric lifting / lowering device mounted on a carriage and a movable vehicle.

DESCRIPTION OF SYMBOLS 1: Electric lifting device 2: Carriage 3a, 3b: Arm 4: Meshing chain 5: Lifting operation part 6: Motor part 7: Reduction gear 8: Coupling 9: Motor driver 10: Control part 11: Power supply 12: Handle grip 13 : Operation unit 14: Top plates 15a, 15b, 15c, 15d Weight detection means (strain gauge type load cell)
17: Weight detection means 18 with speed reducer 18: Support plate 19: Position detection means 20: Elevating support part 21: Stand base part 22: Fixing means 50: Article

Claims (9)

A pedestal for placing items;
A lifting / lowering operation unit that includes a pair of meshing chains and connects one end of the meshing chain to the table to raise and lower the table;
A motor unit for transmitting power to the lifting and lowering unit;
Weight detecting means for detecting a weight applied to the pedestal and outputting a weight signal;
Position detecting means for detecting a lift position of the pedestal unit and outputting a position signal;
From the position signal from the position detection unit and the weight signal from the weight detection unit, a control unit that commands the motor unit so that the pedestal unit is balanced at an arbitrary position;
An electric lifting device characterized by comprising:   The control unit further keeps the article in a balanced state when a predetermined external force smaller than a load of the article is applied to at least one of the pedestal part and the article, and less than the predetermined external force. 2. An external force applied to at least one of the cradle unit and the article allows the article to be selected to move up or down at any time, and issues a command to the motor unit. The electric lifting apparatus as described in. The control unit further controls the pedestal unit so that the pedestal unit is damped in the vertical direction when a force exceeding a predetermined weight is applied to the pedestal unit in a vertically downward direction within a predetermined time. The electric lifting device according to claim 1 or 2.   The said weight detection means has a strain gauge, and detects the weight applied to the said stand part, The electric raising / lowering apparatus as described in any one of Claim 1 to 3 characterized by the above-mentioned.   The electric lifting device according to any one of claims 1 to 4, wherein the motor unit includes a wave gear reducer.   The electric lifting device according to any one of claims 1 to 5, wherein the pedestal unit includes a top plate that is movable in a horizontal direction and a fixing means that fixes a horizontal position of the top plate. .   The weight detection means is provided in at least one of the cradle part, an elevating support part that supports the elevating action part, the elevating action part, and the motor part. The electric lifting apparatus as described in any one of Claims.   The electric lifting device according to claim 7, wherein a plurality of the weight detection means are arranged on the pedestal unit. The electric lifting device according to claim 7 or 8, wherein a plurality of the weight detection means are arranged on the lifting support portion.