JP4255321B2 - Assist conveyance method and apparatus therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an assist conveyance method and an apparatus for reducing the load on an operator when an operator operates a conveyance unit to convey a conveyance object.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there is known a work assisting device to which impedance control is applied that can perform a carrying work while feeling as if a light article is being conveyed, even though a heavy article is being conveyed. This work auxiliary device includes first to eighth movable bodies that support heavy objects, each actuator that moves the movable bodies, and a controller that adjusts the output of the actuators. In order to convey as intended, the force indirectly applied to the heavy load by the worker is detected by the force sensor, and the first to eighth movable bodies are controlled based on this information to reduce the load on the worker. Power assist device (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
JP 2000-84881 A [0004]
[Problems to be solved by the invention]
However, in the work auxiliary device disclosed in Japanese Patent Application Laid-Open No. 2000-84881, when an operator is transporting a heavy object or positioning and attaching a heavy object to an attachment target site, the heavy object becomes an obstacle. Even if it comes into contact, the reaction force generated on the heavy object due to the contact is not transmitted to the operator who operates the device. Therefore, the operator cannot detect that the heavy object is in contact with the obstacle. There is a problem that the carrying work may be continued, and there is a possibility of damaging a heavy object or a site to which the heavy object is attached.
[0005]
The present invention has been made in view of such problems of the prior art, and the object of the present invention is to prevent the transported object and the obstacle from being touched even if the transported object contacts any obstacle during the work. It is an object of the present invention to provide an assist conveyance method and apparatus capable of appropriately transmitting a reaction force caused by contact to an operator without being damaged.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is directed to an assist transfer method for reducing a load on an operator when an operator operates a transfer means to transfer a transfer object. A first slide table that is disposed at the connection portion and is movable in the left-right direction with respect to the traveling direction of the conveyed product, and is disposed so as to overlap the first slide table and vertically with respect to the traveling direction of the conveyed product A movable second slide table, a first cylinder for centering the first slide table, a second cylinder for centering the second slide table, and a front surface of the second slide table are connected. A floating mechanism having a third cylinder that expands and contracts in the same direction as the passing direction of the conveyed product, and a first displacement sensor is built in the first cylinder. First detection means for detecting a first displacement amount in the left-right direction of the first slide table, and a second displacement sensor built in the second cylinder, and the second slide table in the vertical direction Second detection means for detecting a second displacement amount, and a third displacement sensor built in the third cylinder for detecting the third displacement amount in the same direction as the traveling direction of the conveyed product And detecting the impact by displacing at least one of the first cylinder, the second cylinder, and the third cylinder when the conveyed object comes into contact with an obstacle or the like. And at least one of the first displacement amount, the second displacement amount, and the third displacement amount is detected, and a reaction force that increases in proportion to the displacement amount is calculated.
By subtracting the reaction force from the assist driving force generated by the motor, the reaction force is transmitted to an operator who operates the conveying means by the motor .
[0007]
The invention according to claim 2 is the assist transport device to reduce the load on the worker when the worker carries the conveyed object by operating the conveying means, and gripping means for gripping the conveyed object, in order to power assist drive And a first slide table which is arranged at a connecting portion between the gripping means and the conveying means and is movable in the left-right direction with respect to the advancing direction of the conveyed object, and is arranged so as to overlap the first slide table. A second slide table that is movable in a vertical direction with respect to the traveling direction of the conveyed product, a first cylinder that centers the first slide table, and a second that centers the second slide table. Float having a cylinder and a third cylinder connected to the front surface of the second slide table and extending and contracting in the same direction as the traveling direction of the conveyed product A first displacement sensor built in the first cylinder, a first detection means for detecting a first displacement amount in the left-right direction of the first slide table, and the second cylinder A second displacement sensor, a second detection means for detecting a second displacement amount in the left-right direction of the second slide table; a third displacement sensor built in the third cylinder; Third detection means for detecting a third displacement amount in the left-right direction of the third slide table, and detecting at least one displacement amount among the first displacement amount, the second displacement amount, and the third displacement amount. And a control means for calculating a reaction force that increases in proportion to the amount of displacement, and subtracting the reaction force from an assist driving force generated by the motor, thereby transferring the reaction force to the motor. transmitted to the operator to operate by.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a schematic explanatory diagram of an instrument panel mounting station to which an assist conveyance device according to the present invention is applied, FIG. 2 is a schematic perspective view of a floating mechanism, and FIG. 3 is a block diagram of a control system related to power assist control, FIG. 4 is a conceptual explanatory diagram of reaction force detection control, and FIGS. 5 to 7 are explanatory diagrams of a work area setting method.
[0009]
As shown in FIG. 1, in the instrument panel mounting station of the vehicle body assembly line, the vehicle body W positioned on the mounting jig provided on the slat conveyor is continuously conveyed in the direction of arrow A at a constant speed. The assist conveyance device according to the present invention is configured as follows. In FIG. 1, there are two states, that is, a position where the assist conveyance device grips the instrument panel (instrument panel) P (original position) and a position where the instrument panel P is attached to the vehicle body W in the left-right direction (Y direction) of the vehicle body W. Is shown.
[0010]
A first frame 1 is provided substantially above the vehicle assembly line in a direction parallel to the vehicle assembly line (X direction). The first frame 1 is provided with two slide rails 2 and one rack 3 in parallel with the vehicle body assembly line. A plurality of rollers 4 are rotatably engaged with the two slide rails 2, and a pinion gear 6 attached to a motor 5 is engaged with the rack 3. The plurality of rollers 4 and the motor 5 are attached to the support member 7. The motor 5 is a motor for synchronizing the assist conveyance device with the vehicle body W.
[0011]
A second frame 8 is connected to the support members 7 of the plurality of rollers 4 and the motor 5. The second frame 8 is provided with two slide rails 9 and one rack 10 orthogonal to the vehicle body assembly line. A plurality of rollers 11 are rotatably engaged with the two slide rails 9, and a pinion gear 13 attached to a motor 12 is engaged with the rack 10. The plurality of rollers 11 and the motor 12 are attached to the support member 14. The motor 12 is a motor for driving the assist conveyance device in the Y-axis direction with power assist.
[0012]
A third frame 15 is connected to the plurality of rollers 11 and the support member 14 of the motor 12. The third frame 15 is provided with two slide rails 16 and one rack 17 in parallel with the vehicle body assembly line. A plurality of slide guides are slidably engaged with the two slide rails 16, and a pinion gear 20 attached to a motor 19 is engaged with the rack 17. The plurality of slide guides and the motor 19 are attached to the lower surface edge of the table 21. The motor 19 is a motor for driving the assist conveyance device in the X-axis direction with power assist.
[0013]
Further, a telescopic pit slide guide 22 is attached to the center of the lower surface of the table 21, and a feed screw (not shown) is mounted inside the slide guide 22, and a motor 23 is connected to the feed screw. The motor 23 is attached to the table 21 in a standing state. The motor 23 is a motor for driving the assist conveyance device in the vertical direction (Z direction).
[0014]
A columnar arm 24 is extended on the side facing the vehicle body W near the lower end of the slide guide 22, and a box 25 containing a floating mechanism is provided at the tip. An instrument panel gripping means 27 for gripping the instrument panel P via a floating mechanism is provided on the surface of the box 25 facing the traveling direction of the vehicle body W, and an operation handle 28 is provided on the surface of the box 25 facing the vehicle body W. ing.
[0015]
As shown in FIG. 2, the floating mechanism 30 is slidably engaged with the slide rail 31 and a fixed table 32 having a pair of slide rails 31 attached to the front end in the left-right direction (Y direction) of the vehicle body W. A first slide table 34 having a slide guide 33 attached to the rear surface and a pair of slide rails 35 attached to the front end portion of the first slide table 34 in the vertical direction (Z direction) of the vehicle body W are slidably engaged. A second slide table 37 having a slide guide 36 to be fitted on the rear surface is provided.
[0016]
A centering clamping member 38 is provided at the center of the front surface of the fixed table 32, and the piston rod tip is positioned in the left-right direction of the vehicle body W in a state in which the centering clamping member 38 can be clamped on the rear surface of the first slide table 34. A pair of centering cylinders 39 facing in the Y direction are provided. The centering cylinder 39 has a built-in displacement sensor, and the amount of displacement of the first slide table 34 in the left-right direction (Y direction) of the vehicle body W can be constantly confirmed.
[0017]
A centering pinched member 40 is provided in the center of the front surface of the first slide table 34, and the piston rod tip is placed on the rear surface of the second slide table 37 so that the centering pinched member 40 can be pinched. A pair of centering cylinders 41 facing in the vertical direction (Z direction) of W are provided. A displacement sensor is built in the centering cylinder 41, and the amount of displacement of the second slide table 37 in the vertical direction (Z direction) of the vehicle body W can be constantly confirmed.
[0018]
Further, on the front surface of the second slide table 37, a cylinder 42 with the piston rod tip directed in the traveling direction of the vehicle body W is provided, and a pair of slide guides 43 are provided in parallel with the cylinder 42. A rectangular parallelepiped block 44 is fixed to the tip of the piston rod of the cylinder 42 and the tip of the slide guide 43, and an arm 45 for connecting the instrument panel gripping means 27 is provided on the front surface of the block 44. The cylinder 42 has a built-in displacement sensor, and the amount of displacement of the block 44 in the front-rear direction (X direction) of the vehicle body W can be constantly confirmed.
[0019]
As shown in FIG. 1, the instrument panel gripping means 27 includes a base 47 attached to the tip of an arm 45 via a connecting member 46 in the left-right direction (Y direction) of the vehicle body W, and the base 47 A pair of slide rails 48 attached to the left and right sides of the front surface in the left-right direction (Y direction) of the vehicle body W, a pair of slide tables 50 attached to a slide guide 49 slidably engaged with the slide rails 48, and the slide table 50 And a pair of cylinders 53 that slide the support arms 52 toward the reference hole 26 of the instrument panel P.
[0020]
In addition, a load cell (force sensor) for detecting forces in three orthogonal directions is built in the attachment portion of the operation handle 28 of the box 25 that supports the instrument panel gripping means 27, and the vehicle body W is always in the left-right direction (Y direction), A force applied in the longitudinal direction (X direction) of the vehicle body W and in the vertical direction (Z direction) of the vehicle body W is detected. The forces detected by these force sensors are used for power assist control of this apparatus.
[0021]
On the other hand, the amount of displacement detected by the displacement sensor built in each cylinder 39, 41, 42 of the floating mechanism 30 is the reaction force when the instrument panel P gripped by the instrument panel gripping means 27 contacts the vehicle body W or an obstacle. Used to generate.
[0022]
As shown in FIG. 3, the control system related to the power assist control of the assist conveyance device includes a force sensor 60 that detects forces in three orthogonal axes provided on the mounting portion of the operation handle 28, and an orthogonal three axes provided in the floating mechanism 30. Displacement sensor 61 for detecting the amount of displacement in the direction, position command calculation unit 62, position control unit 63, motor (Y-axis) 12, (for X-axis) 19, (for Z-axis) 23 as an actuator for assist drive, It comprises position / speed detection means 64 for detecting the position / speed of the motors 12, 19, 23.
[0023]
Information on the force detected by the force sensor 60 in the left-right direction (Y direction) of the vehicle body W, the front-rear direction (X direction) of the vehicle body W, and the vertical direction (Z direction) of the vehicle body W is input to the position command calculation unit 62. . The position command calculating unit 62 calculates assist driving data F for assisting driving of each motor (for Y-axis) 12, (for X-axis) 19, and (for Z-axis) 23 based on the information of these forces. And input to the position control unit 63.
[0024]
The position controller 63 controls the motors (for Y-axis) 12, (for X-axis) 19, and (for Z-axis) 23 to perform assist driving based on assist driving data F. At that time, the position and speed of each motor (for Y-axis) 12, (for X-axis) 19, and (for Z-axis) 23 are detected by the position / speed detection means 64, and the position command calculation unit 62 and the position control unit 63 Feedback has been provided.
[0025]
As shown in FIG. 4, when the instrument panel P gripped by the instrument panel gripping means 27 contacts the vehicle body W or an obstacle, at least one of the three displacement sensors 61 provided in the floating mechanism 30 detects the displacement amount x. The displacement amount x is input to the position command calculation unit 62. 4 shows one axis (X axis), and the X axis cylinder 42 of the floating mechanism 30 that connects the instrument panel gripping means 27 and the arm 24 of the assist conveyance device has the same characteristics as the spring.
[0026]
The position command calculation unit 62 calculates reaction force generation data f based on the information of the displacement amount x. Here, for example, f = K · x, and K can be set to an arbitrary value, and a feeling of rigidity can be created. Accordingly, the greater the amount of displacement x, the greater the operator feels the reaction force. Note that not only the displacement amount x but also its velocity and acceleration can be used for calculating the reaction force.
[0027]
Then, in the position command calculation unit 62, the reaction force generation data f is obtained from the assist driving data F for assisting driving of each motor (for Y axis) 12, (for X axis) 19, and (for Z axis) 23. The position command value calculated using the subtraction result (F−f) is input to the position control unit 63.
[0028]
The position control unit 63 controls each motor (for Y-axis) 12, (for X-axis) 19, and (for Z-axis) 23 to assist drive while generating a reaction force based on the subtraction result (F-f). . At that time, the position and speed of each motor (for Y-axis) 12, (for X-axis) 19, and (for Z-axis) 23 are detected by the position / speed detection means 64, and the position command calculation unit 62 and the position control unit 63 Feedback has been provided.
[0029]
Further, in the assist conveyance device according to the present invention, if the space within the operating range can be freely moved during the assist operation, it interferes with the vehicle body W or the like, so that as shown in FIG. In order to sandwich the work area We in the operation range in the X direction), a limiter that restricts the movable range by software is provided instead of a mechanical limiter with a sense of impact, and the limit areas La and Lb are located in areas beyond the limiter. Can be set. In addition, limit areas can be provided so as to sandwich the work area We in the operating range in the left-right direction (Y direction) of the vehicle body W and the vertical direction (Z direction) of the vehicle body W.
[0030]
In the work area We, power assist driving by normal impedance control is performed, and in the limit areas La and Lb, control including a stiffness characteristic formula (f = Kd · (x−xd), x> xd or x <−xd). Switch to impedance control using equation. Here, f is a force that causes the instrument panel P to return from the limit areas La and Lb to the work area We, Kd is a spring constant that can be set to an arbitrary value, x is a coordinate value of the end portion of the work (instrument panel P), xd For example, the coordinate value of the vehicle body W with which the end of the workpiece (instrument panel P) may come into contact, (x−xd) is the amount of entry of the workpiece (instrument panel P) into the limit areas La and Lb (from the work area We) Approach distance).
[0031]
Moreover, since the spring constant Kd can be set to any value by software, it is possible to change the value for each limit area, for example, the limit area La and the limit area Lb, and work within the limit areas La and Lb. The value can be changed according to the distance from the area We.
[0032]
In addition, as shown in FIG. 6, when a work (instrument panel P) is synchronized with the vehicle body W conveyed by the slat conveyor and is inserted into the vehicle body W from the opening for the front door and assembled at a predetermined position, The area We and the limit areas La and Lb can be set to move in synchronization with the vehicle body W. In this case, the work area We and the limit areas La and Lb can be set in the coordinate system on the vehicle body W side.
[0033]
Further, as shown in FIG. 7, in one cycle from gripping the work (instrument panel P) to assembling to the vehicle body W, the limit is set according to the operation mode (work input preparation mode, work input mode, in-vehicle movement mode). You can switch areas.
[0034]
For example, in the workpiece loading preparation mode and the workpiece loading mode, limit areas La and Lb can be set at both ends of the operating range in the front-rear direction (X direction) of the vehicle body W perpendicular to the workpiece traveling direction (Y direction). Further, in the in-vehicle movement mode, limit areas Lc and Ld are set at both ends of the operating range in the left-right direction (Y direction) of the vehicle body W where the workpiece may come into contact with the vehicle body W, and the longitudinal direction (X The limit area Lb can be set at one end of the (direction) operating range. Therefore, the work (instrument panel P) can be moved along the limit areas La, Lb, Lc, and Ld.
[0035]
The operation of the assist conveyance device configured as described above and the assist conveyance method will be described. In order to grip the instrument panel P transported to the instrument panel supply position B shown in FIG. 1, the operator operates the operation handle 28 of the assist transport device that is stopped at the original position to open the pair of support arms 52. The instrument panel gripping means 27 is moved to the instrument panel supply position B where the instrument panel P is mounted on the carriage (not shown).
[0036]
Then, after the coupling pin 51 is opposed to the reference hole 26 of the instrument panel P, the cylinder 53 is driven to insert the coupling pin 51 into the reference hole 26, whereby the instrument panel gripping means 27 grips the instrument panel P. Further, when the instrument panel P is lifted from the carriage and the operation handle 28 is operated in the direction in which the instrument panel P is to be moved, each motor (for Y-axis) 12, (for X-axis) 19, and (for Z-axis) 23 is moved by the operator. Assist drive to reduce the load.
[0037]
Next, the operation handle 28 is operated so that the instrument panel P moves in synchronization with the vehicle body W, and the instrument panel P is further transported into the vehicle body W from the front door opening of the vehicle body W, and is provided on the vehicle body W. It is moved to the vicinity of the instrument panel mounting positioning pin Wp. At this time, there is a high possibility that the instrument panel mounting positioning pin Wp contacts the bracket in which the pin insertion guide hole of the instrument panel P is formed, or the end of the instrument panel P contacts the vehicle body W.
[0038]
When the instrument panel P comes into contact with the vehicle body W, a cylinder located in the direction in which the instrument panel P is pushed back among the cylinders 39, 41, 42 provided in the floating mechanism 30 contracts, and the displacement amount is a displacement sensor built in the cylinder. Will detect. Each motor (for the Y axis) 12, (for the X axis) so that the operator operating the assist conveyance device feels the reaction force accompanying the contact between the instrument panel P and the vehicle body W based on the displacement amount detected by the displacement sensor. 19, 23 (for Z axis) is controlled.
[0039]
By such assist control, the operator senses that the instrument panel P has approached its attachment position, and after carrying the instrument panel P to the vicinity of the attachment part of the vehicle body W of the instrument panel P, the operator performs a delicate position adjustment by hand. Assembly work can be performed. Since the position adjustment range at this time can be absorbed by the floating mechanism 30, no impact is applied to the apparatus.
[0040]
When the above assembling work is completed, the operator operates the operation end operation switch when the instrument panel holding means 27 is moved out of the vehicle body W. Then, the assist conveyance device automatically returns to the original position without contacting the vehicle body W or the equipment around the line.
[0041]
Further, since the work area We of the instrument panel gripping means 27 is set in advance by providing limit areas La and Lb, the operator contacts the instrument panel P with the vehicle body W or equipment around the line while transporting the instrument panel P. I will not let you.
[0042]
Further, even if the operator operates the operation handle 28 so that the instrument panel gripping means 27 moves from the work area We to the limit areas La and Lb, the motors 12, 19, and 23 as the power assist drive actuators are not subjected to an impact. Since it is controlled so that it does not occur and a reaction force for returning the instrument panel gripping means 27 to the work area We is generated, no impact is applied to the present apparatus or the instrument panel P. Therefore, the worker can work without being aware of the boundary between the work area We and the limit areas La and Lb.
[0043]
【The invention's effect】
As described above, according to the first aspect of the present invention, when the conveyed object comes into contact with the obstacle, the impact is reduced by providing the floating mechanism between the conveying means and the conveyed object, and the floating mechanism Since the impact force is calculated by calculating the amount of displacement and the reaction force due to this impact force is transmitted to the operator via the transport means, when the worker transports or attaches the transported object to the mounted part, the transported object Even if it touches any obstacle or attached part, the worker can efficiently feel the touch of the carried object in contact with any obstacle or attached part without damaging the carried object or attached part. Work can be done.
[0044]
According to the invention of claim 2, the floating mechanism provided at the connecting portion between the gripping means for gripping the conveyed product and the transporting means, the displacement detecting means for detecting the displacement amount of the floating mechanism, and the displacement detecting means Since the control means that calculates the reaction force by calculating the detected displacement is provided, when the operator transports the object or attaches it to the mounted part, the transferred object contacts any obstacle or attached part. Even so, the transported object or the mounted part will not be damaged.
In addition, the worker can work efficiently while feeling that the conveyed object is in contact with any obstacle or attached part.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view of an instrument panel mounting station to which an assist conveyance device according to the present invention is applied. FIG. 2 is a schematic view of a floating mechanism, in which (a) is a perspective view and (b) is a schematic diagram showing the inside. Fig. 3 is a block diagram of a control system related to power assist control. Fig. 4 is a conceptual diagram of reaction force detection control. Fig. 5 is an explanatory diagram of a work area setting method. Fig. 6 is an explanatory diagram of a work area setting method. 7] Explanation of work area setting method [Explanation of symbols]
12, 19, 23 ... motor, 27 ... instrument panel gripping means, 30 ... floating mechanism, 60 ... force sensor, 61 ... displacement sensor, 62 ... position command calculation part, 63 ... position control part, 64 ... position / speed detection means, P ... Instrument panel, W ... Car body.

Claims (2)

In the assist conveyance method that reduces the load on the worker when the operator operates the conveyance means to convey the conveyed object,
A first slide table that is disposed at a connection portion between the conveyed product and the conveying means and is movable in the left-right direction with respect to the traveling direction of the conveyed product, and is disposed to overlap the first slide table. A second slide table movable in a vertical direction with respect to a traveling direction; a first cylinder for centering the first slide table; a second cylinder for centering the second slide table; A floating mechanism having a third cylinder connected to the front surface of the two slide tables and extending and contracting in the same direction as the direction of travel of the conveyed product;
A first detecting means for incorporating a first displacement sensor in the first cylinder and detecting a first displacement amount in the left-right direction of the first slide table;
A second detecting means for incorporating a second displacement sensor in the second cylinder and detecting a second displacement amount in the vertical direction of the second slide table;
A third detection unit that incorporates a third displacement sensor in the third cylinder and detects a third displacement amount in the same direction as the traveling direction of the conveyed object,
When the conveyed object comes into contact with an obstacle or the like , the impact is reduced by displacing at least one of the first cylinder, the second cylinder, and the third cylinder ,
Assist generated by the motor by detecting at least one of the first displacement amount, the second displacement amount, and the third displacement amount, calculating a reaction force that increases in proportion to the displacement amount, and An assist conveyance method , wherein the reaction force is transmitted to an operator who operates the conveyance means by the motor by subtracting the reaction force from a driving force . In the assist transfer device that reduces the load on the operator when the operator operates the transfer means to transfer the transfer object,
Gripping means for gripping the conveyed product;
A motor for driving the power assist;
A first slide table that is disposed at a connection portion between the gripping means and the transport unit and is movable in the left-right direction with respect to the traveling direction of the transport object, and is disposed on the first slide table, A second slide table that is movable in a vertical direction with respect to the traveling direction, a first cylinder that centers the first slide table, a second cylinder that centers the second slide table, A floating mechanism having a third cylinder connected to the front surface of the second slide table and extending and contracting in the same direction as the traveling direction of the conveyed product;
A first detecting means for incorporating a first displacement sensor in the first cylinder and detecting a first displacement amount in the left-right direction of the first slide table;
A second detection means for incorporating a second displacement sensor in the second cylinder and detecting a second displacement amount in the left-right direction of the second slide table;
Third detection means for incorporating a third displacement sensor in the third cylinder and detecting a third displacement amount in the left-right direction of the third slide table;
Control means for detecting at least one displacement amount among the first displacement amount, the second displacement amount, and the third displacement amount, and calculating a reaction force that increases in proportion to the displacement amount;
An assist conveyance device , wherein the reaction force is transmitted to an operator who operates the conveyance means by the motor by subtracting the reaction force from an assist driving force generated by the motor .

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