Data processing: generic control systems or specific application – Generic control system – apparatus or process – Digital positioning
Reexamination Certificate
2000-12-20
2004-03-02
Picard, Leo (Department: 2125)
Data processing: generic control systems or specific application
Generic control system, apparatus or process
Digital positioning
C700S062000
Reexamination Certificate
active
06701196
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an assembling method to be carried out by an assembling robot and, more particularly, to an automatic position-finding assembling method for inserting an insert member into a mating hole of a receiving fib when assembling a predetermined assembly, and an automatic position-finding assembling apparatus for carrying out the method.
2. Description of the Related Art
A multiple disk clutch is one of assemblies that are assembled by a position-finding assembling method. The multiple disk clutch is formed by alternately placing inner disks (receiving members), i.e., internally toothed disks, and outer disks, i.e., externally toothed disks, in a space defined by a cylindrical member. Both the inner disks and the outer disks are flat annular members and have center openings, respectively. Each of the inner disks is provided with a plurality of internal teeth on its inner circumference while each of the outer disks is provided with a plurality of external teeth on its outer circumference. The inner circumferences of the inner disk and the outer disks form a substantially cylindrical space. A shaft (insert member) provided on its outer surface with a plurality of axial splines is inserted in the substantially cylindrical space with the splines thereof engaging the internal teeth of the inner disks. The cylindrical member is provided in its inner circumference with a plurality of grooves. The external teeth of the outer disks engage the plurality of grooves of the cylindrical member.
When assembling the multiple disk clutch, the inner disks and the outer disks are inserted alternately in the space in the cylindrical member with the external teeth of the outer disks engaging the grooves of the cylindrical member, and then the shaft is inserted in the substantially cylindrical space defined by the inner and the outer disks. More concretely, the shaft is turned properly to find an angular position where the splines of the shaft are able to engage the internal teeth of the outermost inner disk, and the shaft is inserted in the center opening of the outermost inner disk. Subsequently, the shaft is advanced into the substantially cylindrical space and the shaft is turned together with the outermost inner disk engaged with the shaft and is properly moved axially back and forth to find an angular position where the spines of the shaft are able to engage the internal teeth of the second outermost inner disk. Thus, an operation for finding an engaging position where the splines of the shaft are able to engage the internal teeth of the inner disk and an operation for inserting the shaft into the center opening of the inner disk are repeated alternately to assemble the multiple disk clutch.
When thus assembling the multiple disk clutch, the inner disks are not restrained at all from movement in the cylindrical member and the positions and the angular positions of the inner disks are variable before the shaft is inserted in the inner disks. Consequently, the inner disks move away from the shaft and the internal teeth of the inner disks are dislocated from an engaging position where the same are able to engage the splines of the shaft. Therefore, operations for finding an engaging position where the splines of the shaft are able to engage the internal teeth of the inner disks and for pushing the shaft into the openings of the inner disks must unavoidably depend on the feeling of a skilled hand.
Attempts have been made to carry out such assembling operations automatically by an assembling robot. An assembling method that guides a shaft, i.e., an insert member, into the tapered receiving hole of a workpiece, i.e., a receiving member, and an assembling method that aligns an insert member with the receiving hole of a receiving member by a simple groping reciprocating operation of a mechanism are proposed in JP-A Nos. 57-184639 and 62-204035.
Although the prior art assembling method that tapers the receiving hole of a workpiece is effective in expanding the range of positions of the insert member relative to the receiving hole of the receiving member where the insert member can be inserted in the receiving hole, this assembling method require subjecting the receiving member to a functionally unnecessary machining process and requires changes in design. The assembling method that uses simple groping reciprocating operation needs a special hand for assembling an assembly of an insert member and a receiving member, and needs different special hands for assembling different assemblies. When the assembling mood that uses the simple groping reciprocation is applied to assembling, for example, a multiple disk clutch, friction disks are liable to move together with a shaft or the shaft is liable to be caught by the friction disks and becomes immovable. Consequently, it takes a long time for finding the internal teeth of the friction plate and hence the assembling work cannot be precisely and quickly carried out.
SUMMARY OF THE INVENTION
The present invention has been made in view of those problems and it is therefore an object of the present invention to provide an automatic position-finding assembling method for assembling an assembly by inserting an insert member into a mating opening of a receiving member, capable of quickly and surely finding an engaging position where the insert member is able to engage the receiving member and of precisely and quickly carrying out assembling work, and an automatic position-finding assembling apparatus for carrying out the method.
According to a first aspect of the present invention, an automatic position-finding assembling method for inserting an insert member held by an end effector of an assembling robot into a mating opening of a receiving member to assemble a predetermined assembly, comprises the steps of: positioning the insert member relative to the mating opening of the receiving member by moving the insert member held by the end effector relative to the receiving member; and pressing the insert member against the receiving member by a pressing force applied to the insert member in a direction parallel to a third axis by the end effector compliant with respect to directions parallel to first and second axes perpendicular to the third axis; wherein in the step of pressing the insert member against the receiving member, the compliance center of the insert member is moved along a predetermined groping route with the pressing force applied to the insert member in the direction parallel to the third axis by the end effector.
In the automatic position-finding assembling method in the first aspect of the present invention, it is preferable that the groping route is set for repetition of a radially outward movement from a position near the center of the mating opening of the receiving member in different phases in a plane defined by the first and the second axes.
In the automatic position-finding assembling method in the first aspect of the present invention, it is preferable that the groping route is a cloverleaf route expressed by the following expressions representing x and y coordinates on a plane defined by the first axis as x-axis and the second axis as y-axis:
x=A
x
{sin(&ohgr;
t
)+sin(
n&ohgr;t
)}
y=A
y
{cos(&ohgr;
t
)±cos(
n&ohgr;t
)}
where A
x
and A
y
are amplitudes (leaf size), n is a real number (relating to number of leaves), &ohgr; is a velocity of groping motion and t is time. Please note that n is a real number and not necessarily an integer.
In the step of pressing the insert member against the receiving fiber in the automatic position-finding assembling method in the first aspect of the present invention, it is preferable that the pressing force produced by the end effector is reduced during the movement of the compliance center of the insert member along the grouping route. It is preferable that the insert member held by the end effector is rotated periodically about its axis in the step of pressing the insert member agains
Fujimori Jun
Itoko Toshiyuki
Kagaya Hiroaki
Miyahara Keizo
Kawaskai Jukogyo Kabushiki Kaisha
Oliff & Berridg,e PLC
Picard Leo
Shechtman Sean P.
LandOfFree
Method and apparatus for automatic position-finding assembling does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for automatic position-finding assembling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for automatic position-finding assembling will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3235558