CA1075275A - Jointed manipulator with controlled play indexing - Google Patents
Jointed manipulator with controlled play indexingInfo
- Publication number
- CA1075275A CA1075275A CA313,064A CA313064A CA1075275A CA 1075275 A CA1075275 A CA 1075275A CA 313064 A CA313064 A CA 313064A CA 1075275 A CA1075275 A CA 1075275A
- Authority
- CA
- Canada
- Prior art keywords
- arm
- axis
- respect
- around
- sprocket
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/02—Programme-controlled manipulators characterised by movement of the arms, e.g. cartesian coordinate type
- B25J9/04—Programme-controlled manipulators characterised by movement of the arms, e.g. cartesian coordinate type by rotating at least one arm, excluding the head movement itself, e.g. cylindrical coordinate type or polar coordinate type
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J15/00—Gripping heads and other end effectors
- B25J15/06—Gripping heads and other end effectors with vacuum or magnetic holding means
- B25J15/0616—Gripping heads and other end effectors with vacuum or magnetic holding means with vacuum
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/10—Programme-controlled manipulators characterised by positioning means for manipulator elements
- B25J9/1005—Programme-controlled manipulators characterised by positioning means for manipulator elements comprising adjusting means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/10—Programme-controlled manipulators characterised by positioning means for manipulator elements
- B25J9/104—Programme-controlled manipulators characterised by positioning means for manipulator elements with cables, chains or ribbons
- B25J9/1045—Programme-controlled manipulators characterised by positioning means for manipulator elements with cables, chains or ribbons comprising tensioning means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/10—Programme-controlled manipulators characterised by positioning means for manipulator elements
- B25J9/106—Programme-controlled manipulators characterised by positioning means for manipulator elements with articulated links
Landscapes
- Engineering & Computer Science (AREA)
- Robotics (AREA)
- Mechanical Engineering (AREA)
- Manipulator (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A two-armed jointed manipulator is provided, with a holder which moves along a linear locus by the movement of the second arm being indexed to the movement of the first arm. This indexing has a degree of controlled play so that at its ends the locus changes its direction sharply for a short distance, and so that a degree of resilience is provided against shocks.
A two-armed jointed manipulator is provided, with a holder which moves along a linear locus by the movement of the second arm being indexed to the movement of the first arm. This indexing has a degree of controlled play so that at its ends the locus changes its direction sharply for a short distance, and so that a degree of resilience is provided against shocks.
Description
This invention relates to a jointed manipulator for holding an object and manipulating it, for instance, for transferring it from one position to another, as on an assembly line. Particularly, this invention relates to a jointed manipulator which has a body, a first arm pivoted to the body at one end of the first arm, a second arm pivoted by one of its ends to the other end of the first arm, and a holder which is pivoted to the second arm at the other end of the second arm, which is used by pivoting the first and second arms so as to transfer the object which is held by the holder.
A manipulator of this kind is frequently used for moving an object to and from an automatic press machine or the like, or for transferring an object from a belt conveyor to a processor, etc A conventional manipulator of this type includes driving means in the body, one pivoting the fir~t arm and another pivoting the second arm with respect to the first arm (usually by way of chains or the like), and link means which connect the body and the holder so that the holder is maintained in a fixed orientation.
Thus the system has two degrees of freedom, since the second arm can be moved independently of the motion of the first arm. Such systems are described in, for example, U.S. Patents Nos. 2,861,699 and 4,065,001.
` 1075275 Usually in such manipulators the axes of pivoting of the arms and the holder are all parallel, although other possibilities exist; and the following discussion will be conducted on the assumption of s parallel axes.
These manipulators have the advantages of simple construction, and furthermore because they have two degrees of freedom the holder can be moved along any cpmplicated locus desired within a certain range, by suitably energizing and synchronizing the operation of the drive means. However, in some applications this flexibility of operation is not necessary. For instancç, when the manipulator is used for feeding and clearing a pressing machine, fiimple straight-line movement of the holder is sufficient. A conventional manipulator with two degrees of freedom, therefore, which requires co-ordination of the operation of the two drive means, is rather more complicated than necessary for such a function. For automatic operation, the simpler the control of the manipulator, the better.
An important consideration with regard to the design of such a manipulator is that it is de~irable that the reach of the arms, in both directions, should be as wide as possible. Therefore it is a design goal for the two arms to be able to be extended so as to be collinear, and for this collinear assembly to be extensible in opposite directions to one side and to the other, so as to maximize the reach of the manipulator.
` 1075Z75 In copending Canadian Patent Application No. 313,063 filed concurrently herewith by the same applicant as the pre-sent application and assigned to the same assianee, it is proposed to provide a jointed manipulator which has a simple construction and is controlled simply, and in which the first and the second arms are jointly driven by a single drive means, and are constrained in their movement so that the entire apparatus has one degree of freedom, so that the holder is compelled to move along a single linear locus, to and fro.
In this copending application, further, is provided a jointed manipulator in which the first and the second arms, which are constrained in their motion so that the entire apparatus has one degree of freedom, can be extended from their collinear position on one side of the machine, through their coincident completely folded position, to their collinear fully extended position on the other side of the machine, thus moving the holder through a line from one side of the machine to the other, said line being as long as possible, thus maximising the reach of the machine.
Further, in the aforementi~ned application i~ provided a jointed manipulator in which a holder is moved linearly and in which it is maintained in the same orientation with respect to the base of the machine while it is being moved.
Thus, in the aforementioned application is provided a jointed manipulator comprising a body, a first arm of which one end is pivotally mounted around a first axis to the body, a second arm of which one end is pivotally mounted around a second axis to the other end of the first arm remote from the body, a holder for holding material to be manipulated, which ' 1075275 is pivotally mounted around a third axis to the other end of the second arm remote from the first arm, a drive means for pivoting the first arm around the first axis with respect to the body, a coupling means which pivots the second arm around the second axis with respect to the first arm, the amount of said pivoting bearing a fixed proportional relation to the amount of pivoting provided by the drive means of the first arm around the first axis with respect to the body, and a constraining means which constrains the holder to be in a fixed rotational orientation with respect to the body, as the arms are pivoted, by rotating the holder about the third axis with respect to the second arm.
The present invention relates to an improvement in lS the coupling means which moves the second arm relative to the first arm.
In more detail, in the previous invention the coupling means ensured that the amount of pivoting of the second arm around the second axis relative to the first arm was strictly proportional to the amount of pivoting of the first arm around the first axis relative to the body. This meant that in the previous invention the holder was moved through a linear locus, and in the case of the first arm and the second arm being of the same length, and the proportional ratio being ,two to one, the locus was a straight line. This was a convenient type of motion for such an arm. However, a need arose for a different sort of motion - one where the holder moved through a linear locus, and at the ends of the locus, the direction of motion of the holder changed abruptly through almost a right angle, and the holder moved for a short distance in the new direction.
1~7S275 As will be seen in the description of a preferred embodiment, one possible use for such a motion is when the manipulator is to be used for picking up an object, moving it, and putting it down again. Other uses could be imagined for such a motion, however.
Also another need that was felt that led to the present invention was protection from shocks.
The device of the previous invention had no flexibility in its linkage, and if a sudden force was applied to the holder in any way, as by an operator stumbling against it, for instance, it was quite possible that the machinery would be damaged, due to the inflexibility of the coupling means.
Therefore the present invention has as an object the provision of a manipulator which is easily and simply controlled and moves an object in a linear locus, and which is of a simple and robust construction, and which moves the object in a locus the ends of which are sharply turned through a great angle and continue for a short distance in that direction, Further, the present invention has as another object the provision of a manipulator which has a certain reilience in its linkage so that any sudden shock given to the material holder can be absorbed by the machinery without damage.
Accordin~ to the present invention, therefore, these objects ~re accomplished by a jointed manipulator comprising a body, a first arm of which one end is pivotally mounted around a first axis to the body, a second arm of which one end is pivotally mounted around a second axis to the other end of tha first arm remote from the body, a holder for holdin~ material to be manipulated, which is pivotally mounted around a third axis to the other end of the second arm remote from the first arm, a drive means for pivoting the first arm around the first ax;.s with respect to the body, a constraining means which co~strains the holder to be in a fixed rotational orientation with respect to the body as the arms are pivoted by rotating the holder about the third axis with respect to the second arm, and a coupling means, comprising ~ proportion maintaining means which pivots the second arm around the second axis with respect to the first arm, the amount of said pi~oting bearing a proportional relation to the amount of pivoting provided ~y the drive means of the first arm around the first axis with respect to the body, a limited play means which allows the said proportional relation to alter within a certain limited range about the exactly proportional amount, when a twisting force of moment greater than a certain minimum moment is applied to the second arm, and a stop means which limits the movement of the second arm around the second axis with respect to the first arm within a certain limited range.
Other objects, features and advantages will be appartent from the following description of a preferred ~075275 embodiment, taken with reference to the accompanying drawings, which are given for the sake of illustration only, and thus are not to be considered as limitative of the scope of the invention, and wherein:
Fig. 1 is a front view partly in section of a jointed manipulator according to the present invention;
Fig. 2 is a longitudinal sectional view of the manipulator, taken along the line II - II in Fig. l;
Fig. 3 is a longitudinal sectional view, taken along the line III - III in Fig. 2;
Fig. 4 is a longitudinal cross-section taken along the line IV - IV cf Fig. 2;
Fig. 5 is a longitudinal cross-section taken along the line V - V of Fig. 2;
Fig. 6 i8 a longitudinal cross-section taken along the line VI - VI of Fig. 2;
Fig. 7 is a transverse sectional view, taken along the line IV - IV in Fig. l;
and Fig. 8 is a schematic front view of a jointed manipulator according to ~he present invention, aiding in the explanation of its operation.
In Figs. 1 and 2 there is shown a jointed manipulator according to the present invention, which comprifies a body 2 fixed to a support, a first arm 3 of which one end is pivotally mounted to the lower end of the body 2, a second arm 4 of which one end is pivotally connected to the other end of the first arm 3, and of which ithe other end is pivotally connected to a material holder 5 which is adapted to hold a material object to be manipulated.
According to the previous invention a constraining means is provided which constrains the holder for the material to be manipulated to maintain a fixed orientation relative to the body, although of course its actual position changes. This ensures stable - manipulation.
Further, according to the present invention there iB provided a coupling means, which forces the second arm to rotate relative to the first arm at a rate proportional to the rate at which the first arm rotates relative to the body. Thus the holder is forced to move along a linear locus. In the present embodiment, the second arm is approximately the same length as the first arm, and this proportional rate is approximately two to one, so that th:ls linear locus is approximately a straight line for most of its length.
Other possibilities would be useful, however, in other particular applications. The essence of the present invention is that this proportionality is not strict, because a certain degree of controlled play is provided _ 9 _ by the coupling means, which allows the said proportional relation to alter within a certain limited range about the exactly proportional amount when a twisting force greater than a certain minimum moment is applied to the second arm. As will be explained later, this limited play, in combination with a stop means to be explained later which is provided as part of the coupling means, and which limits the movement of the second arm with respect to the first arm, results in the effect that the linear locus of the holder has at its extremities two short portions which are inclined at almost a right angle to its major portion. In the present embodiment these short portions provide a sort of picking-up and putting-down effect, which is very useful indeed in practice.
In the present embodiment these constraining and coupling means are provided by assemblies of sprocket wheels and axles and endless chains stretched around the sprocket wheels in a manner to be described, and the function of limited and controlled play is provided by a stop arm and two air cylinders. In other embodiments, however, other arrangements could be used.
As shown in Figs. 2 and 3, the body 2 comprises a lower frame 8 which is secured to the end of a support block 6 which is indicated by two-dotted lines, by bolts 7 also shown by two-dotted lines.
The lower frame 8 comprises a rear plate 9 secured to the support block 6, a front plate 10 which is parallel to the rear plate 9 a certain distance away from it, a bottom plate 11 having a U-shape, which is connected to the lower ends of the rear plate 9 and the front plate 10, an upper plate 12 which is connected to the upper ends of the rear plate 9 and the front plate 10, and a side cover 18 having a U-shape, which is attached around the lower portions of the frame 8.
A pair of fluid prexsure cylinders 14 are arranged in parallel as mounted on the upper plate 12, and in each of these a piston 15 is disposed and moves up and down in answer to fluid pressure supplied.
To the center of each piston 15 is mounted, by a nut 16a, a piston rod 16 which projects downward through the cylinder 14 and through a hole in the upper plate 12.
The outer periphery of the piston 15 and the contact surfaces of the upper plate 12 and the piston rod 16 are sealed by proper sealing materials 17, 18, and 19, as well known in the art.
The space above the pistons 15 in the cylinders 14 is open to the atmosphere, and the spaces below them are supplied with fluid pressure, in thi~ embodiment air pressure, as required, by a compressor which is not shown, via holes 21 formed in the upper plate 12 and conduits 20 attached thereto. The pair of cylinder~ 14 compose substantially one system for driving the manipulator of the present invention.
An upper frame 22 is disposed on the cylinders 14 and comprisex a lower plate 23 arranged on the cylinders 14, a pair of front and rear plates 24 and 25 which are mounted on the lower plate 23 parallel to one another a certain distance apart, a top plate 26 placed on top of the front and rear plates 24 and 25, and a top cover 27 which is attached over the top of the top plate 26 as shown in Fig. 3 so as to form a top space thereover. The lower plate 23 of the upper frame 22 is mounted to the upper plate 12 of the lower frame 8 by bolts and nuts 28 via the cylinders 14. The lower plate 23 includes a pair of holes 29, through each of which a chain 37 connected to the top of the pistons 15 passes.
In the upper frame 22 a hanger mem~er 32 having an upside-down U-shape is suspended from the top plate 26 in its center by a bolt 31 which is secured to the top plate 26 by a pair of nuts 30. The height of the hanger member 32 may therefore be adjusted by rotating the nuts 30 to raise or lower the bolt 31.
A body sprocket 35 is supported by the hanger mem~er 32 in its lower portion via a support shaft 33 which is extended in the front and rear directions past the hanger member 32, and by bearings 34 such as needle bearings interposed between the sproc~et 35 and the support shaft 33. Th~ ends of the support shaft 33 are fitted into longitudinal slots 36 formed in the front and rear plates 24 and 25, so that the support shaft 33 may move upwards and downwards in the slots 3~, but not sideways.
The chain 37 passes around the sprocket 35 and each end of it is connected to the top of one of the piston rods 16, after passing through one of the holes 29 in the lower plate 23.
The arrangements for mounting the arm 3 to the body 2 will now be described.
A sleeve 39 is rotatably mounted to the lower portion of the lower frame 8 between the front plate 10 and the rear plate 9 by way of bearings 38 such as needle bearings, and both its ends project to the outside past the plates. On the front end (the left end in Fig. 2) of the sleeve 39 is formed a flange 39a having an enlarged diameter, and on the rear end (the right end in the ~igure) of the sleeve 39 are disposed a stop plate 40 for retaining the sleeve 39 in place, and a nut 41.
On the outside of the sleeve 39, inside the lower part of the body 2, is secured a drive sprocket 43 by a key 42. Around this drive sprocket 43 passes a chain 44, the ends of which are connected to the lower ends of the piston rods 16.
Thus it will be seen that, by supply of fluid pressure to the one or the other of the cylinders 14, the assembly consisting of the cylinders 14, the sprockets 43 and 35, and the chains 37 and 44 may be displaced in the one direction or the other selectively, and thus the drive sprocket 43 may be rotated in the one direction or the other. Thus this assembly constitutes a drive means for the manipulator. The tension of the chains may be adjusted by the nuts 30 in an obvious manner.
The first arm 3 is provided with a first arm frame 59 which is connected firmly to the front end of the sleeve 39. This frame 59 comprises a rear plate 60 of which the lower part in the figure is coupled to the front end of the flange 39a of the sleeve 39, a front plate 61 which is parallel to the rear plate 60 and is ~paced a certain distance away from it, a bottom plate 62 of a U-shape, which is connected to the lower ends of the rear and the front plates 60 and 61, and an upper plate 63 which is connected to the upper ends of the rear and front plates 6~
and 61. Thus it is seen that the first arm frame 59 may be rotated arount the axis of the sleeve 39, which will be hereinafter called the first axis, by rotating the drive sprocket 43 by the drive means.
Through the hollow inside of the sleeve 39 a first shaft 46 is fitted coaxially, and its ends project outwards from either end of the sleeve 39~
On the rear end of the first shaft 46 is secured, by a key 48 and a nut 49, a stop member 47 which extends upwards and i8 engaged with a limited play means 50 which is the essence of this invention.
Fig. 4 shows the limited play means 50. As seen in Fig. 2, it is mounted to the lower rear surface of the rear plate 9 of the lower frame 8. The stop member 47 is held between two pistons 54 of two air cylinders 52 which are continuously supplied, during operation of the manipul&tor, with compressed zir, from conduits 56 through openings 57. The outer peripheries of the pistons 54 are sealed by seals SS. The entire assembly is held together by a stop block 51, as seen in Fig. 2. Ea~h of the cylinders 5~ has a slot 53 in its lower inner side, and the stop block 51 is 80 arranged, as seen in Fig. 4, that it prevents the pistons moving past the points which keep the stop member 47 in the central position.
It will be clear that the operation of this limited play means 50 ix to keep the end of the stop member 47 fixed in the central position until the shaft 46 is twisted with respect to the body 2 with more than a certain minimum torque. When such twist is applied, however, the shaft 46 is allowed to turn a little until the stop member 47 comes into contact with the end of one or the other of the slots 53. This turning of the shaft 46 is against the smooth resistance of one or the other of the pistons 54, as it is pressed inwards into its cylinder against the pressure of the compressed air. The other piston 54 does not participate in the motion, as it is stopped from moving outwards by the stop block 51.
~urther, as soon as the torque applied to the shaft 46 becomes less than the certain minimum torque, the pressure of the air in the compressed one of the cylinders 52 returns the stop member 47 to the central position and holds it there.
The construction of the remainder of the manipulator will now be described.
~07S275 On the lower front surface of the front plate 10 of the lower frame 8 is fixed a sprocket 58 coaxial to the sleeve 39 about the first axis, but not contacting the sleeve 39. This will hereinafter be called the third fiprocket. This sprocket cannot rotate with respect to the body 2.
The first shaft 46 passes through the lower portions of the rear and the front plates 60 and 61 of the first arm 3 via bearings 64 mounted to the rear and the front plates 60 and 61. In parenthesis, the rear end of the shaft 46 is also supported in a bearing which is not designated by any reference numeral in Fig. 2 but may be seen therein, and which is fitted in the sleeve 39. The front end of the first shaft 46 project~ frontwards past the front plate 61 and is provided with a stop nut 65 mountea on it which prevents the first shaft from slipping out rightwards in the figure. A dust cover 66 is mounted to the front plate 61 over the end of the shaft 46.
A sprocket 68, hereinafter called the first sproc~et, with two sets of gear teeth, is secured to the first shaft 46 between the rear and the front plates ~0 and 61 of the first arm 3 by way of a key 67. ~ence this sprocket is normally fixed with respect to the body 2 until it is twisted with a force greater than the certain minimum force necessary to move the limited play means 50. Further, as a particular feature of the present invention, a stopper piece 69 is provided on the rear surface of the first sprocket 68, and two stopper pieces 70 and 71 are attached to the front surface of the rear plate 60 of the first arm frame 59 so that the rotation of the first arm with respect to the first sprocket is limited in either direction. As explained later, this will mean that the rotation of the second arm with respect to the first arm is limited.
The arrangements for mounting the second arm 4 to the first arm 3 will now be described.
At the upper portion in the figure of the first arm 3, which is the other end of it from the end which pivots around the first axis, are arranged an arm sleeve 72 and a second sprocket 73, which has two rows of gear teeth, and these are coupled together by a coupling pin 74a. This assembly is pivoted in holes in the front and the rear plates 61 and 60 by bearings 74b.
The diameter of the first sprocket 68, in this embodiment, is twice as large as that of the second sprocket 73.
Between these sprockets 6~ and 73 are extended a pair of endless chains 81.
A second shaft 75 is coaxially fitted into the combination of the arm sleeve 72 and the second spro~ket 73 via bearings 76 mounted therein, and may therefore rotate therein. The ends of the second shaft 75 project out from the ends of the arm sleeve 72.
1~75Z75 On the rear end of the second shaft 75 is mounted securely a fourth sprocket 77 via a key 78 inserted there-between, by a nut 79. An endless chain 80 is stretched between the third sprocket 58 and the fourth sprocket 77.
In this embodiment the diameters of the third and the fourth sprockets are the same. A first arm cover 98 is attached to the frame 59 over the sproc~ets 77 and 58 and the chain 80, and this cover covers up all of the first arm 3 except its front. The axis of the second shaft 75 and the sleeve 72 and sprockets 73 and 77 will hereinafter be called the second axis.
In order to adjust the tension of the endless chains 80 and 81, tension control means 82 and 83 are arranged in the central rear surfaces of the rear plate 60 and the front plate 61 of the first arm frame 59. These tension control means are not essential to the present invention but they will be briefly described here in the interests of complete-ness of explanation.
The tension control means 82 comprises a base plate 84 having a vertical groove in its central rear surface, an arm support member 85 which is attached to the lower rear surface of the base plate 84 and has a -r ~ .~.
~ 18 ~
pair of side grooves in its side ends, a pair of arms 87 having inward projections 87a, the lower end of each of which is fitted in a side ~roove of the support member 85 and is pivotally connected to it by a pin 86, and a pair of tension rollers 88 which are pivotally mounted by pins B9 to the fork~ e upper ends of the arms 87, and which contact with the endless chain 80.
lQ An arm push member 91 of a generally pentagonal shape is slidably fitted in the vertical groove of the base plate 84 and moves between the base plate 84 and a hold plate 90 having a vertical slot 92 in its center which is mounted to the arm support member 85 and projects upwards. The top of the arm push member 91 contact& the inward projections 87a of the arms 87. A
guide pin 93 is mounted to the arm push member 91 through the slot 92 of the hold plate 90.
A vertical screwed hole is formed in the midd~e of the arm support member 85. A tension control screw bolt 95 is screwed into the screwed hole of the arm support member 85 and is fixed by a stop nut 94.
When the screw bolt 95 is moved upwards it pushes the arm push member 91 upwards, and the inward pro~ections 87a are pushed outwards by the arm push member 91. Thus the arms 87 together with the rollers 88 are pivoted outwards, thereby controlling the tension of the endless chain 80.
The tension control means 83 has the same structure as the one 82 described above, except that two coaxial tension rollers are mounted to each ~rm 87, ~o that ~oth the chains 81 may be adjusted together. The tenfiion control meanfi 83 and 82 are illustrated in Figs. S and 6, and the same reference numerals are ufied for corresponding parts in the two figures. Further explanation will be omitted for the sake of brevity, since these tension control means are not essential to the present invention. Openings 96 covered by plates 97 are provided in the first arm frame 59 for adjustment of the tension control screws 95.
Now the s~cond arm will be described. It includes a frame 99, as shown in Figfi. 1 and 2, and this frame 99 is secured to the front end of the arm sleeve 72 and rotates together therewith about the second axis. A fifth sprocket 101 is mounted to the second shaft 75 at its front end where it projects out of the sleeve 72 by a nut 102, and is secured thereto by a key 100.
In this embodiment the second arm 4 is the same length as the first arm 3. At the other end of the frame 99 of the second arm 4, therefore, at a distance away from the second axis the same as the distance between the first and the second axes, is pivotally attached a third shaft 103, which has a sixth sprocket 104 firmly attached to it by a nut 107.
The holder for the material to be manipulated, designated ~y 5, which includes an arm 105 having an L-shape, is also arranged on the third shaft 103 and is mounted to the sixth sprocket 104 by screw~ 106.
An endless chain 108 is stretched between the fifth and sixth sprockets 101 and 104. The axis of the third shaft 103 will hereinafter be called the third axis.
In this embodiment the diameters of the fifth and the sixth sprockets are the same. A second arm cover 120 is attached over the frame 99 of the second arm 4 and covers the fifth and sixth sprockets 101 and 104 and the chain 108. This cover in fact covers all of the front of the second arm 4, except for the fact that a slit 121 is provided in the lower end portion of the cover so that the arm 105 may be able to rotate around the third axis without interference from the cover.
A tension control means 109 is disposed to the central front surface of the second arm frame 99 in order to adjust the tension of the endless chain 108.
This tension control means is almost the same as the tension control means 82 and a3 ~ except that the arms move inwards instead of outwards. Although the tension control means 109 is not essential to the present invention, it will be descri~ed in the interests of completeness of explanation. A pair of L-shaped arms 113, each having an inward projection 113a, are pi~otally mo~nted to the base plate 110 by pins 112 in their corner portions.
- Tension rollers 114 are pivotally mounted in the lower ends of the lower projections of each arm 113 by pins 115, and are adapted to be contacted with the endless chain 108 from the outside. A support member 111 is ~.o~5Z75 mounted to the frame 99 just under the base plate 110 and includes a vertical screwed hole in its center. A
tensicn control screw bolt 119 is sGrewed into the screwed hole of the support member 111 and is fixed by a stop nut 118. An arm push member 117 which is fitted slidably into the vertical groove of the base plate 110 is interposed between the base plate 110 and a hold plate 116 which is mounted to the support member 111 and projects upwards. When the screw bolt 119 is moved upwards it pushes the arm push member 117 upwards, and the inward projections 113a are pushed up and outwards by the arm push member 117. Consequently the arms 113 together with the rollers 114 are pivoted inwards, thereby controlling the tension of the endless chain 108.
The material holder, shown in Figures 1 and 7, comprises the L-shaped arm 1~5, a pivot arm 124 pivotally mounted to the bottom of the horizontal portion of the arm 105, an H-shaped holder frame 128 attached to the pivot arm 124, and suction cups 129 fixed to the holder frame 128.
~s .
1075'~75 A hooknose 122a formed at the right hand end 122 as seen in Fig. 1 of the arm 105 engages with a hooknose formed on the pivot arm 124. Thus, as will be seen from the figure, the pivot arm, which is pivoted to the arm 105 by the pin 123, can pivot up and down by just a little. The valve seat 126 made of an elastic material such as rub~er is mounted in the small opening 125 in the arm 105 so that when the pivot arm 124 is raised it interrupts flow of fluid therethrough. A flexible conduit 127 leads from the opening 125 to a pressure sensor and a compressor which are not shown.
Normally, when the pivot arm 124 is hanging in the lower position, the flow of air through the hole 125 is not interrupted, and the pressure ~ensor does not act. However, when the holder 5 is brought into contact from above with an object to be manipulated, the arm 124 is raised so as to interrupt the flow of air through the hole 125, and this activates the pressure sensor. This then supplies vacuum pressure from a source of vacuum which is not shown to the suction cups 129, via the conduit 131, a distributor 130, and branch tubes 131a.
Therefore the suction cups grab firmly the object which is to be manipulated.
Compres~ed air type suction cups of a wel -known type may also be used which are activated by supply of compressed air instead of vacuum. In this case, the same compressor can be used for all the powering functions of the manipulator of the present invention.
The operation of the manipulator described above will now be explained.
First, it will be clear to anyone skilled in the mechanical arts that the third, fourth, fifth, and sixth sprockets 58, 77, 101, and 104 of the machine described above will function so as to constrain the holder 5 to be always in a fixed orientation with respect to the body 2, in combination with the endless chains 80 and 108 stretched around them, as the arms 3 and 4 are moved by operation of the cylinders 14.
It will be clear to such a skilled person that the essential condition for this is that the product of the diameters of the fourth and sixth sprockets should be e~ual to the product of the diameters of the third and fifth sprockets, and in this embodiment this condition is fulfilled. These sproc~ets and chains therefore constitute a constraining means which rotates the holder about the third axis so as to keep it in a fixed orientation with respect to the body. Of course the machine of the present invention is initially adjusted so that the holder is horizontal, and by the action of this constraining means, therefore, it remains horizontal at all times.
It would however be quite within the scope of the present invention to provide this constraining means in a different way, and various other method~ will be apparent to the man skilled in the art upon mature consideration.
1075Z~75 Next, in the manipulator described above, the first and second sprockets 68 and 73, and the chain 81 passed around them, constitute a proportion maintaining means which pivots the second arm around the second axis with respect to the first arm. It wil~ be realized that the small degree of limited play provided by the limited play means 50 is not employed during normal movement of the arms in the central portion of their travel, because there is not sufficient torque on the shaft 46 to operate the limited play means. TherefoEe, since the lengths of the arms are equal, and the radius of the second sprocket is half that of the first sprocket, and the first sprocket is, in default of operation of the limited play means 50, essentially fixed to the body 2, it will be easily appreciated that, assuming that the app~ratus is initially adjusted so that when the first arm is upright the second arm is upright, when the first arm has rotated through an angle x with respect to the vertical, the second arm is forcibly rotated, by the first and second sprockets and the chain, through an angle 2x in the contrary direction relative to the first arm, and therefore through an angle of x relative to the vertical, in the contrary direction. Thus the third axis is always maintained at th~ same level as the first axis, and moves from side to side in a straight line as the drive sprocket is turned by the drive means. This motion is illustrated in Fig. 8 by the positions of the arms labelled C to B to A to E.
However, this ratio of two to one for the proportion of the amount of turning of the second ~rm about the first arm to the amount of turning of the first arm about the body is not essential to the principle of the manipulator described above, nor is it an essential principle of the present invention.
Any fixed proportion will still cause the third axi to move in a fixed line locus as the apparatus is operated, although such a locus would of course not be a straight line. Further, it is not essential to the present invention that the second arm be of the same length as the first arm. That is, it is not essential that the distance between the first and the second axes be the same as the distance between the ~econd and the thi~d axes. In some embodiments the second arm might be provided as longer or shorter than the first arm, and, although of course this too would mean that the locus of the third axis would no longer be a straight line, this might be useful in some applications.
Further, it would be quite within the scope of the present invention to provide the proportion maintaining means ~etween the rotations of the first arm about the body and the second arm about the first arm in a different way, and many other possibilities will be evident to one skilled in the mechanical arts.
The function of the limited play means of the present invention is as follows. During the main portion of the travel of the two arms, that is, from position A
in Fig. 8, where the two arms are vertical, through position B, which is an intermediate position, to position C, wherein the arms are extended to the left, the limited play means does not operate, because not enough torque is put upon the shaft 46. Therefore, as described above, strict proportionality is maintained by the proportional maintaining means, this proportion of rotations of the first arm relative to the body and the second arm relative to the first arm being two to one.
However, when the arms reach position C, it is so arranged that the stopper 69 contacts the stopper 71, and therefore further turning of the first arm about the first sprocket is prevented. This means that further turning of the second arm about the first arm is prevented. If there were no limited play means 50, therefore, the machinery would be fixed and unable to move any further in the direction of counterclockwise rotation of the first arm, as seen in Fig. 8. However, the drive means is still acting, and it is quite strong enough to operate the limited play means by driving the stop member 47 against one of the pistons 54 and driving that piston into its cylinder. Thus, although zero rotation of the second arm relative to the first arm is occurring, rotation of the first arm with respect to the body can still occur for
A manipulator of this kind is frequently used for moving an object to and from an automatic press machine or the like, or for transferring an object from a belt conveyor to a processor, etc A conventional manipulator of this type includes driving means in the body, one pivoting the fir~t arm and another pivoting the second arm with respect to the first arm (usually by way of chains or the like), and link means which connect the body and the holder so that the holder is maintained in a fixed orientation.
Thus the system has two degrees of freedom, since the second arm can be moved independently of the motion of the first arm. Such systems are described in, for example, U.S. Patents Nos. 2,861,699 and 4,065,001.
` 1075275 Usually in such manipulators the axes of pivoting of the arms and the holder are all parallel, although other possibilities exist; and the following discussion will be conducted on the assumption of s parallel axes.
These manipulators have the advantages of simple construction, and furthermore because they have two degrees of freedom the holder can be moved along any cpmplicated locus desired within a certain range, by suitably energizing and synchronizing the operation of the drive means. However, in some applications this flexibility of operation is not necessary. For instancç, when the manipulator is used for feeding and clearing a pressing machine, fiimple straight-line movement of the holder is sufficient. A conventional manipulator with two degrees of freedom, therefore, which requires co-ordination of the operation of the two drive means, is rather more complicated than necessary for such a function. For automatic operation, the simpler the control of the manipulator, the better.
An important consideration with regard to the design of such a manipulator is that it is de~irable that the reach of the arms, in both directions, should be as wide as possible. Therefore it is a design goal for the two arms to be able to be extended so as to be collinear, and for this collinear assembly to be extensible in opposite directions to one side and to the other, so as to maximize the reach of the manipulator.
` 1075Z75 In copending Canadian Patent Application No. 313,063 filed concurrently herewith by the same applicant as the pre-sent application and assigned to the same assianee, it is proposed to provide a jointed manipulator which has a simple construction and is controlled simply, and in which the first and the second arms are jointly driven by a single drive means, and are constrained in their movement so that the entire apparatus has one degree of freedom, so that the holder is compelled to move along a single linear locus, to and fro.
In this copending application, further, is provided a jointed manipulator in which the first and the second arms, which are constrained in their motion so that the entire apparatus has one degree of freedom, can be extended from their collinear position on one side of the machine, through their coincident completely folded position, to their collinear fully extended position on the other side of the machine, thus moving the holder through a line from one side of the machine to the other, said line being as long as possible, thus maximising the reach of the machine.
Further, in the aforementi~ned application i~ provided a jointed manipulator in which a holder is moved linearly and in which it is maintained in the same orientation with respect to the base of the machine while it is being moved.
Thus, in the aforementioned application is provided a jointed manipulator comprising a body, a first arm of which one end is pivotally mounted around a first axis to the body, a second arm of which one end is pivotally mounted around a second axis to the other end of the first arm remote from the body, a holder for holding material to be manipulated, which ' 1075275 is pivotally mounted around a third axis to the other end of the second arm remote from the first arm, a drive means for pivoting the first arm around the first axis with respect to the body, a coupling means which pivots the second arm around the second axis with respect to the first arm, the amount of said pivoting bearing a fixed proportional relation to the amount of pivoting provided by the drive means of the first arm around the first axis with respect to the body, and a constraining means which constrains the holder to be in a fixed rotational orientation with respect to the body, as the arms are pivoted, by rotating the holder about the third axis with respect to the second arm.
The present invention relates to an improvement in lS the coupling means which moves the second arm relative to the first arm.
In more detail, in the previous invention the coupling means ensured that the amount of pivoting of the second arm around the second axis relative to the first arm was strictly proportional to the amount of pivoting of the first arm around the first axis relative to the body. This meant that in the previous invention the holder was moved through a linear locus, and in the case of the first arm and the second arm being of the same length, and the proportional ratio being ,two to one, the locus was a straight line. This was a convenient type of motion for such an arm. However, a need arose for a different sort of motion - one where the holder moved through a linear locus, and at the ends of the locus, the direction of motion of the holder changed abruptly through almost a right angle, and the holder moved for a short distance in the new direction.
1~7S275 As will be seen in the description of a preferred embodiment, one possible use for such a motion is when the manipulator is to be used for picking up an object, moving it, and putting it down again. Other uses could be imagined for such a motion, however.
Also another need that was felt that led to the present invention was protection from shocks.
The device of the previous invention had no flexibility in its linkage, and if a sudden force was applied to the holder in any way, as by an operator stumbling against it, for instance, it was quite possible that the machinery would be damaged, due to the inflexibility of the coupling means.
Therefore the present invention has as an object the provision of a manipulator which is easily and simply controlled and moves an object in a linear locus, and which is of a simple and robust construction, and which moves the object in a locus the ends of which are sharply turned through a great angle and continue for a short distance in that direction, Further, the present invention has as another object the provision of a manipulator which has a certain reilience in its linkage so that any sudden shock given to the material holder can be absorbed by the machinery without damage.
Accordin~ to the present invention, therefore, these objects ~re accomplished by a jointed manipulator comprising a body, a first arm of which one end is pivotally mounted around a first axis to the body, a second arm of which one end is pivotally mounted around a second axis to the other end of tha first arm remote from the body, a holder for holdin~ material to be manipulated, which is pivotally mounted around a third axis to the other end of the second arm remote from the first arm, a drive means for pivoting the first arm around the first ax;.s with respect to the body, a constraining means which co~strains the holder to be in a fixed rotational orientation with respect to the body as the arms are pivoted by rotating the holder about the third axis with respect to the second arm, and a coupling means, comprising ~ proportion maintaining means which pivots the second arm around the second axis with respect to the first arm, the amount of said pi~oting bearing a proportional relation to the amount of pivoting provided ~y the drive means of the first arm around the first axis with respect to the body, a limited play means which allows the said proportional relation to alter within a certain limited range about the exactly proportional amount, when a twisting force of moment greater than a certain minimum moment is applied to the second arm, and a stop means which limits the movement of the second arm around the second axis with respect to the first arm within a certain limited range.
Other objects, features and advantages will be appartent from the following description of a preferred ~075275 embodiment, taken with reference to the accompanying drawings, which are given for the sake of illustration only, and thus are not to be considered as limitative of the scope of the invention, and wherein:
Fig. 1 is a front view partly in section of a jointed manipulator according to the present invention;
Fig. 2 is a longitudinal sectional view of the manipulator, taken along the line II - II in Fig. l;
Fig. 3 is a longitudinal sectional view, taken along the line III - III in Fig. 2;
Fig. 4 is a longitudinal cross-section taken along the line IV - IV cf Fig. 2;
Fig. 5 is a longitudinal cross-section taken along the line V - V of Fig. 2;
Fig. 6 i8 a longitudinal cross-section taken along the line VI - VI of Fig. 2;
Fig. 7 is a transverse sectional view, taken along the line IV - IV in Fig. l;
and Fig. 8 is a schematic front view of a jointed manipulator according to ~he present invention, aiding in the explanation of its operation.
In Figs. 1 and 2 there is shown a jointed manipulator according to the present invention, which comprifies a body 2 fixed to a support, a first arm 3 of which one end is pivotally mounted to the lower end of the body 2, a second arm 4 of which one end is pivotally connected to the other end of the first arm 3, and of which ithe other end is pivotally connected to a material holder 5 which is adapted to hold a material object to be manipulated.
According to the previous invention a constraining means is provided which constrains the holder for the material to be manipulated to maintain a fixed orientation relative to the body, although of course its actual position changes. This ensures stable - manipulation.
Further, according to the present invention there iB provided a coupling means, which forces the second arm to rotate relative to the first arm at a rate proportional to the rate at which the first arm rotates relative to the body. Thus the holder is forced to move along a linear locus. In the present embodiment, the second arm is approximately the same length as the first arm, and this proportional rate is approximately two to one, so that th:ls linear locus is approximately a straight line for most of its length.
Other possibilities would be useful, however, in other particular applications. The essence of the present invention is that this proportionality is not strict, because a certain degree of controlled play is provided _ 9 _ by the coupling means, which allows the said proportional relation to alter within a certain limited range about the exactly proportional amount when a twisting force greater than a certain minimum moment is applied to the second arm. As will be explained later, this limited play, in combination with a stop means to be explained later which is provided as part of the coupling means, and which limits the movement of the second arm with respect to the first arm, results in the effect that the linear locus of the holder has at its extremities two short portions which are inclined at almost a right angle to its major portion. In the present embodiment these short portions provide a sort of picking-up and putting-down effect, which is very useful indeed in practice.
In the present embodiment these constraining and coupling means are provided by assemblies of sprocket wheels and axles and endless chains stretched around the sprocket wheels in a manner to be described, and the function of limited and controlled play is provided by a stop arm and two air cylinders. In other embodiments, however, other arrangements could be used.
As shown in Figs. 2 and 3, the body 2 comprises a lower frame 8 which is secured to the end of a support block 6 which is indicated by two-dotted lines, by bolts 7 also shown by two-dotted lines.
The lower frame 8 comprises a rear plate 9 secured to the support block 6, a front plate 10 which is parallel to the rear plate 9 a certain distance away from it, a bottom plate 11 having a U-shape, which is connected to the lower ends of the rear plate 9 and the front plate 10, an upper plate 12 which is connected to the upper ends of the rear plate 9 and the front plate 10, and a side cover 18 having a U-shape, which is attached around the lower portions of the frame 8.
A pair of fluid prexsure cylinders 14 are arranged in parallel as mounted on the upper plate 12, and in each of these a piston 15 is disposed and moves up and down in answer to fluid pressure supplied.
To the center of each piston 15 is mounted, by a nut 16a, a piston rod 16 which projects downward through the cylinder 14 and through a hole in the upper plate 12.
The outer periphery of the piston 15 and the contact surfaces of the upper plate 12 and the piston rod 16 are sealed by proper sealing materials 17, 18, and 19, as well known in the art.
The space above the pistons 15 in the cylinders 14 is open to the atmosphere, and the spaces below them are supplied with fluid pressure, in thi~ embodiment air pressure, as required, by a compressor which is not shown, via holes 21 formed in the upper plate 12 and conduits 20 attached thereto. The pair of cylinder~ 14 compose substantially one system for driving the manipulator of the present invention.
An upper frame 22 is disposed on the cylinders 14 and comprisex a lower plate 23 arranged on the cylinders 14, a pair of front and rear plates 24 and 25 which are mounted on the lower plate 23 parallel to one another a certain distance apart, a top plate 26 placed on top of the front and rear plates 24 and 25, and a top cover 27 which is attached over the top of the top plate 26 as shown in Fig. 3 so as to form a top space thereover. The lower plate 23 of the upper frame 22 is mounted to the upper plate 12 of the lower frame 8 by bolts and nuts 28 via the cylinders 14. The lower plate 23 includes a pair of holes 29, through each of which a chain 37 connected to the top of the pistons 15 passes.
In the upper frame 22 a hanger mem~er 32 having an upside-down U-shape is suspended from the top plate 26 in its center by a bolt 31 which is secured to the top plate 26 by a pair of nuts 30. The height of the hanger member 32 may therefore be adjusted by rotating the nuts 30 to raise or lower the bolt 31.
A body sprocket 35 is supported by the hanger mem~er 32 in its lower portion via a support shaft 33 which is extended in the front and rear directions past the hanger member 32, and by bearings 34 such as needle bearings interposed between the sproc~et 35 and the support shaft 33. Th~ ends of the support shaft 33 are fitted into longitudinal slots 36 formed in the front and rear plates 24 and 25, so that the support shaft 33 may move upwards and downwards in the slots 3~, but not sideways.
The chain 37 passes around the sprocket 35 and each end of it is connected to the top of one of the piston rods 16, after passing through one of the holes 29 in the lower plate 23.
The arrangements for mounting the arm 3 to the body 2 will now be described.
A sleeve 39 is rotatably mounted to the lower portion of the lower frame 8 between the front plate 10 and the rear plate 9 by way of bearings 38 such as needle bearings, and both its ends project to the outside past the plates. On the front end (the left end in Fig. 2) of the sleeve 39 is formed a flange 39a having an enlarged diameter, and on the rear end (the right end in the ~igure) of the sleeve 39 are disposed a stop plate 40 for retaining the sleeve 39 in place, and a nut 41.
On the outside of the sleeve 39, inside the lower part of the body 2, is secured a drive sprocket 43 by a key 42. Around this drive sprocket 43 passes a chain 44, the ends of which are connected to the lower ends of the piston rods 16.
Thus it will be seen that, by supply of fluid pressure to the one or the other of the cylinders 14, the assembly consisting of the cylinders 14, the sprockets 43 and 35, and the chains 37 and 44 may be displaced in the one direction or the other selectively, and thus the drive sprocket 43 may be rotated in the one direction or the other. Thus this assembly constitutes a drive means for the manipulator. The tension of the chains may be adjusted by the nuts 30 in an obvious manner.
The first arm 3 is provided with a first arm frame 59 which is connected firmly to the front end of the sleeve 39. This frame 59 comprises a rear plate 60 of which the lower part in the figure is coupled to the front end of the flange 39a of the sleeve 39, a front plate 61 which is parallel to the rear plate 60 and is ~paced a certain distance away from it, a bottom plate 62 of a U-shape, which is connected to the lower ends of the rear and the front plates 60 and 61, and an upper plate 63 which is connected to the upper ends of the rear and front plates 6~
and 61. Thus it is seen that the first arm frame 59 may be rotated arount the axis of the sleeve 39, which will be hereinafter called the first axis, by rotating the drive sprocket 43 by the drive means.
Through the hollow inside of the sleeve 39 a first shaft 46 is fitted coaxially, and its ends project outwards from either end of the sleeve 39~
On the rear end of the first shaft 46 is secured, by a key 48 and a nut 49, a stop member 47 which extends upwards and i8 engaged with a limited play means 50 which is the essence of this invention.
Fig. 4 shows the limited play means 50. As seen in Fig. 2, it is mounted to the lower rear surface of the rear plate 9 of the lower frame 8. The stop member 47 is held between two pistons 54 of two air cylinders 52 which are continuously supplied, during operation of the manipul&tor, with compressed zir, from conduits 56 through openings 57. The outer peripheries of the pistons 54 are sealed by seals SS. The entire assembly is held together by a stop block 51, as seen in Fig. 2. Ea~h of the cylinders 5~ has a slot 53 in its lower inner side, and the stop block 51 is 80 arranged, as seen in Fig. 4, that it prevents the pistons moving past the points which keep the stop member 47 in the central position.
It will be clear that the operation of this limited play means 50 ix to keep the end of the stop member 47 fixed in the central position until the shaft 46 is twisted with respect to the body 2 with more than a certain minimum torque. When such twist is applied, however, the shaft 46 is allowed to turn a little until the stop member 47 comes into contact with the end of one or the other of the slots 53. This turning of the shaft 46 is against the smooth resistance of one or the other of the pistons 54, as it is pressed inwards into its cylinder against the pressure of the compressed air. The other piston 54 does not participate in the motion, as it is stopped from moving outwards by the stop block 51.
~urther, as soon as the torque applied to the shaft 46 becomes less than the certain minimum torque, the pressure of the air in the compressed one of the cylinders 52 returns the stop member 47 to the central position and holds it there.
The construction of the remainder of the manipulator will now be described.
~07S275 On the lower front surface of the front plate 10 of the lower frame 8 is fixed a sprocket 58 coaxial to the sleeve 39 about the first axis, but not contacting the sleeve 39. This will hereinafter be called the third fiprocket. This sprocket cannot rotate with respect to the body 2.
The first shaft 46 passes through the lower portions of the rear and the front plates 60 and 61 of the first arm 3 via bearings 64 mounted to the rear and the front plates 60 and 61. In parenthesis, the rear end of the shaft 46 is also supported in a bearing which is not designated by any reference numeral in Fig. 2 but may be seen therein, and which is fitted in the sleeve 39. The front end of the first shaft 46 project~ frontwards past the front plate 61 and is provided with a stop nut 65 mountea on it which prevents the first shaft from slipping out rightwards in the figure. A dust cover 66 is mounted to the front plate 61 over the end of the shaft 46.
A sprocket 68, hereinafter called the first sproc~et, with two sets of gear teeth, is secured to the first shaft 46 between the rear and the front plates ~0 and 61 of the first arm 3 by way of a key 67. ~ence this sprocket is normally fixed with respect to the body 2 until it is twisted with a force greater than the certain minimum force necessary to move the limited play means 50. Further, as a particular feature of the present invention, a stopper piece 69 is provided on the rear surface of the first sprocket 68, and two stopper pieces 70 and 71 are attached to the front surface of the rear plate 60 of the first arm frame 59 so that the rotation of the first arm with respect to the first sprocket is limited in either direction. As explained later, this will mean that the rotation of the second arm with respect to the first arm is limited.
The arrangements for mounting the second arm 4 to the first arm 3 will now be described.
At the upper portion in the figure of the first arm 3, which is the other end of it from the end which pivots around the first axis, are arranged an arm sleeve 72 and a second sprocket 73, which has two rows of gear teeth, and these are coupled together by a coupling pin 74a. This assembly is pivoted in holes in the front and the rear plates 61 and 60 by bearings 74b.
The diameter of the first sprocket 68, in this embodiment, is twice as large as that of the second sprocket 73.
Between these sprockets 6~ and 73 are extended a pair of endless chains 81.
A second shaft 75 is coaxially fitted into the combination of the arm sleeve 72 and the second spro~ket 73 via bearings 76 mounted therein, and may therefore rotate therein. The ends of the second shaft 75 project out from the ends of the arm sleeve 72.
1~75Z75 On the rear end of the second shaft 75 is mounted securely a fourth sprocket 77 via a key 78 inserted there-between, by a nut 79. An endless chain 80 is stretched between the third sprocket 58 and the fourth sprocket 77.
In this embodiment the diameters of the third and the fourth sprockets are the same. A first arm cover 98 is attached to the frame 59 over the sproc~ets 77 and 58 and the chain 80, and this cover covers up all of the first arm 3 except its front. The axis of the second shaft 75 and the sleeve 72 and sprockets 73 and 77 will hereinafter be called the second axis.
In order to adjust the tension of the endless chains 80 and 81, tension control means 82 and 83 are arranged in the central rear surfaces of the rear plate 60 and the front plate 61 of the first arm frame 59. These tension control means are not essential to the present invention but they will be briefly described here in the interests of complete-ness of explanation.
The tension control means 82 comprises a base plate 84 having a vertical groove in its central rear surface, an arm support member 85 which is attached to the lower rear surface of the base plate 84 and has a -r ~ .~.
~ 18 ~
pair of side grooves in its side ends, a pair of arms 87 having inward projections 87a, the lower end of each of which is fitted in a side ~roove of the support member 85 and is pivotally connected to it by a pin 86, and a pair of tension rollers 88 which are pivotally mounted by pins B9 to the fork~ e upper ends of the arms 87, and which contact with the endless chain 80.
lQ An arm push member 91 of a generally pentagonal shape is slidably fitted in the vertical groove of the base plate 84 and moves between the base plate 84 and a hold plate 90 having a vertical slot 92 in its center which is mounted to the arm support member 85 and projects upwards. The top of the arm push member 91 contact& the inward projections 87a of the arms 87. A
guide pin 93 is mounted to the arm push member 91 through the slot 92 of the hold plate 90.
A vertical screwed hole is formed in the midd~e of the arm support member 85. A tension control screw bolt 95 is screwed into the screwed hole of the arm support member 85 and is fixed by a stop nut 94.
When the screw bolt 95 is moved upwards it pushes the arm push member 91 upwards, and the inward pro~ections 87a are pushed outwards by the arm push member 91. Thus the arms 87 together with the rollers 88 are pivoted outwards, thereby controlling the tension of the endless chain 80.
The tension control means 83 has the same structure as the one 82 described above, except that two coaxial tension rollers are mounted to each ~rm 87, ~o that ~oth the chains 81 may be adjusted together. The tenfiion control meanfi 83 and 82 are illustrated in Figs. S and 6, and the same reference numerals are ufied for corresponding parts in the two figures. Further explanation will be omitted for the sake of brevity, since these tension control means are not essential to the present invention. Openings 96 covered by plates 97 are provided in the first arm frame 59 for adjustment of the tension control screws 95.
Now the s~cond arm will be described. It includes a frame 99, as shown in Figfi. 1 and 2, and this frame 99 is secured to the front end of the arm sleeve 72 and rotates together therewith about the second axis. A fifth sprocket 101 is mounted to the second shaft 75 at its front end where it projects out of the sleeve 72 by a nut 102, and is secured thereto by a key 100.
In this embodiment the second arm 4 is the same length as the first arm 3. At the other end of the frame 99 of the second arm 4, therefore, at a distance away from the second axis the same as the distance between the first and the second axes, is pivotally attached a third shaft 103, which has a sixth sprocket 104 firmly attached to it by a nut 107.
The holder for the material to be manipulated, designated ~y 5, which includes an arm 105 having an L-shape, is also arranged on the third shaft 103 and is mounted to the sixth sprocket 104 by screw~ 106.
An endless chain 108 is stretched between the fifth and sixth sprockets 101 and 104. The axis of the third shaft 103 will hereinafter be called the third axis.
In this embodiment the diameters of the fifth and the sixth sprockets are the same. A second arm cover 120 is attached over the frame 99 of the second arm 4 and covers the fifth and sixth sprockets 101 and 104 and the chain 108. This cover in fact covers all of the front of the second arm 4, except for the fact that a slit 121 is provided in the lower end portion of the cover so that the arm 105 may be able to rotate around the third axis without interference from the cover.
A tension control means 109 is disposed to the central front surface of the second arm frame 99 in order to adjust the tension of the endless chain 108.
This tension control means is almost the same as the tension control means 82 and a3 ~ except that the arms move inwards instead of outwards. Although the tension control means 109 is not essential to the present invention, it will be descri~ed in the interests of completeness of explanation. A pair of L-shaped arms 113, each having an inward projection 113a, are pi~otally mo~nted to the base plate 110 by pins 112 in their corner portions.
- Tension rollers 114 are pivotally mounted in the lower ends of the lower projections of each arm 113 by pins 115, and are adapted to be contacted with the endless chain 108 from the outside. A support member 111 is ~.o~5Z75 mounted to the frame 99 just under the base plate 110 and includes a vertical screwed hole in its center. A
tensicn control screw bolt 119 is sGrewed into the screwed hole of the support member 111 and is fixed by a stop nut 118. An arm push member 117 which is fitted slidably into the vertical groove of the base plate 110 is interposed between the base plate 110 and a hold plate 116 which is mounted to the support member 111 and projects upwards. When the screw bolt 119 is moved upwards it pushes the arm push member 117 upwards, and the inward projections 113a are pushed up and outwards by the arm push member 117. Consequently the arms 113 together with the rollers 114 are pivoted inwards, thereby controlling the tension of the endless chain 108.
The material holder, shown in Figures 1 and 7, comprises the L-shaped arm 1~5, a pivot arm 124 pivotally mounted to the bottom of the horizontal portion of the arm 105, an H-shaped holder frame 128 attached to the pivot arm 124, and suction cups 129 fixed to the holder frame 128.
~s .
1075'~75 A hooknose 122a formed at the right hand end 122 as seen in Fig. 1 of the arm 105 engages with a hooknose formed on the pivot arm 124. Thus, as will be seen from the figure, the pivot arm, which is pivoted to the arm 105 by the pin 123, can pivot up and down by just a little. The valve seat 126 made of an elastic material such as rub~er is mounted in the small opening 125 in the arm 105 so that when the pivot arm 124 is raised it interrupts flow of fluid therethrough. A flexible conduit 127 leads from the opening 125 to a pressure sensor and a compressor which are not shown.
Normally, when the pivot arm 124 is hanging in the lower position, the flow of air through the hole 125 is not interrupted, and the pressure ~ensor does not act. However, when the holder 5 is brought into contact from above with an object to be manipulated, the arm 124 is raised so as to interrupt the flow of air through the hole 125, and this activates the pressure sensor. This then supplies vacuum pressure from a source of vacuum which is not shown to the suction cups 129, via the conduit 131, a distributor 130, and branch tubes 131a.
Therefore the suction cups grab firmly the object which is to be manipulated.
Compres~ed air type suction cups of a wel -known type may also be used which are activated by supply of compressed air instead of vacuum. In this case, the same compressor can be used for all the powering functions of the manipulator of the present invention.
The operation of the manipulator described above will now be explained.
First, it will be clear to anyone skilled in the mechanical arts that the third, fourth, fifth, and sixth sprockets 58, 77, 101, and 104 of the machine described above will function so as to constrain the holder 5 to be always in a fixed orientation with respect to the body 2, in combination with the endless chains 80 and 108 stretched around them, as the arms 3 and 4 are moved by operation of the cylinders 14.
It will be clear to such a skilled person that the essential condition for this is that the product of the diameters of the fourth and sixth sprockets should be e~ual to the product of the diameters of the third and fifth sprockets, and in this embodiment this condition is fulfilled. These sproc~ets and chains therefore constitute a constraining means which rotates the holder about the third axis so as to keep it in a fixed orientation with respect to the body. Of course the machine of the present invention is initially adjusted so that the holder is horizontal, and by the action of this constraining means, therefore, it remains horizontal at all times.
It would however be quite within the scope of the present invention to provide this constraining means in a different way, and various other method~ will be apparent to the man skilled in the art upon mature consideration.
1075Z~75 Next, in the manipulator described above, the first and second sprockets 68 and 73, and the chain 81 passed around them, constitute a proportion maintaining means which pivots the second arm around the second axis with respect to the first arm. It wil~ be realized that the small degree of limited play provided by the limited play means 50 is not employed during normal movement of the arms in the central portion of their travel, because there is not sufficient torque on the shaft 46 to operate the limited play means. TherefoEe, since the lengths of the arms are equal, and the radius of the second sprocket is half that of the first sprocket, and the first sprocket is, in default of operation of the limited play means 50, essentially fixed to the body 2, it will be easily appreciated that, assuming that the app~ratus is initially adjusted so that when the first arm is upright the second arm is upright, when the first arm has rotated through an angle x with respect to the vertical, the second arm is forcibly rotated, by the first and second sprockets and the chain, through an angle 2x in the contrary direction relative to the first arm, and therefore through an angle of x relative to the vertical, in the contrary direction. Thus the third axis is always maintained at th~ same level as the first axis, and moves from side to side in a straight line as the drive sprocket is turned by the drive means. This motion is illustrated in Fig. 8 by the positions of the arms labelled C to B to A to E.
However, this ratio of two to one for the proportion of the amount of turning of the second ~rm about the first arm to the amount of turning of the first arm about the body is not essential to the principle of the manipulator described above, nor is it an essential principle of the present invention.
Any fixed proportion will still cause the third axi to move in a fixed line locus as the apparatus is operated, although such a locus would of course not be a straight line. Further, it is not essential to the present invention that the second arm be of the same length as the first arm. That is, it is not essential that the distance between the first and the second axes be the same as the distance between the ~econd and the thi~d axes. In some embodiments the second arm might be provided as longer or shorter than the first arm, and, although of course this too would mean that the locus of the third axis would no longer be a straight line, this might be useful in some applications.
Further, it would be quite within the scope of the present invention to provide the proportion maintaining means ~etween the rotations of the first arm about the body and the second arm about the first arm in a different way, and many other possibilities will be evident to one skilled in the mechanical arts.
The function of the limited play means of the present invention is as follows. During the main portion of the travel of the two arms, that is, from position A
in Fig. 8, where the two arms are vertical, through position B, which is an intermediate position, to position C, wherein the arms are extended to the left, the limited play means does not operate, because not enough torque is put upon the shaft 46. Therefore, as described above, strict proportionality is maintained by the proportional maintaining means, this proportion of rotations of the first arm relative to the body and the second arm relative to the first arm being two to one.
However, when the arms reach position C, it is so arranged that the stopper 69 contacts the stopper 71, and therefore further turning of the first arm about the first sprocket is prevented. This means that further turning of the second arm about the first arm is prevented. If there were no limited play means 50, therefore, the machinery would be fixed and unable to move any further in the direction of counterclockwise rotation of the first arm, as seen in Fig. 8. However, the drive means is still acting, and it is quite strong enough to operate the limited play means by driving the stop member 47 against one of the pistons 54 and driving that piston into its cylinder. Thus, although zero rotation of the second arm relative to the first arm is occurring, rotation of the first arm with respect to the body can still occur for
2~ a small angle. ~t may therefore be properly said that the limited play means is allowing the proportional relation ~which in this case is t~o to one) to alter within a certain limited range about the strictly proportional amount.
This occurs when a twisting force of moment greater than a certain moment is applied to the second arm, or, more generally, when twi~ting moment which is in a direction to alter the sa,d proportion is applied anywhere in the s~stem.
10752'75 Therefore, as explained abo~e, for a short angle the first and the second arms, which are fixed with respect to one another, rotate together about the first axis. This means that the third axis i5 moved vertically downwards for a certain short distance, in a direction almost perpendicular to its previous movement. Thus it moves from position C in Fig. 8, to position D. In this position the holder 5 contacts an object to be moved, and, as described above, the suction cups grab the object. A control means which is not shown then reverses the direction of the drive means so as to rotate the first arm clockwise about the first axis.
The manipulator then moves from position D through position C
and position A to position E, where the arms are extended rightwards. In the same fashion as above the stop 69 now contacts the stop 70, and further movement of the second arm with respect to the first arm is prevented. The drive means now again forces the limited play means ~0 to allow variation of the strictly proportional relation of two to one between the rotation of the second arm about the first arm and the first arm about the body, and the two arms rotate together as one body from position E to position F. According to particular control means which are not detailed, the pressure sensor then acts and causes the suction cups to release the object to be manipulated.
Further, these control means reverse the operation of the drive means so as to reverse the operation of the arms and to bring the holder back to position D to pick up another object in another cycle.
1~752~5 ~s shown in Fig. 8, for example, the manipulator 1 of the present invention is applied to a press machine 200 having a mold 201 and a ram 202 positioned just above the mold 201, and manipulates an object 210a from the left hand side to the right hand side on the mold 201. The object 210a is pressed by moving down the ram 202 and is then manipulated from the mold 201 in the same manner as described above. Then, another object 210b is manipulated onto the mold 201 in the same manner as described above.
It will be apparent that, due to the functioning of the limited play means 50 of the present invention, at the ends of the locus through which the object is moved its direction of motion is altered sharply through nearly a right angle, for a short distance. In the described embodiment this is very useful for picking up and putting down objects. According to the present invention the construction of the manipulator is very simple, robust, cheap, and easy to service.
Another useful function of the limited play device of the present invention is as a protection again~t shocks.
It will be easily seen that if a sudden torque is applied to one of the arms, as for instance by an operator stumbling against the material holder, the limited play device 50 functions as a shock absorber and absorbs some of the impact on the machinery, which, if it were not cushioned, might cause serious damage to an inflexible structure.
Although the invention has been shown and described with respect to a preferred embodiment thereof, it should be understood that various changes and modifications could be made therein by a person skilled in the mechanical art, without departing from the scope of the invention, and therefore it is not intended that the description of the embodiment given above should limit the scope of protection sought, which scope is to be defined solely by the appended claims.
This occurs when a twisting force of moment greater than a certain moment is applied to the second arm, or, more generally, when twi~ting moment which is in a direction to alter the sa,d proportion is applied anywhere in the s~stem.
10752'75 Therefore, as explained abo~e, for a short angle the first and the second arms, which are fixed with respect to one another, rotate together about the first axis. This means that the third axis i5 moved vertically downwards for a certain short distance, in a direction almost perpendicular to its previous movement. Thus it moves from position C in Fig. 8, to position D. In this position the holder 5 contacts an object to be moved, and, as described above, the suction cups grab the object. A control means which is not shown then reverses the direction of the drive means so as to rotate the first arm clockwise about the first axis.
The manipulator then moves from position D through position C
and position A to position E, where the arms are extended rightwards. In the same fashion as above the stop 69 now contacts the stop 70, and further movement of the second arm with respect to the first arm is prevented. The drive means now again forces the limited play means ~0 to allow variation of the strictly proportional relation of two to one between the rotation of the second arm about the first arm and the first arm about the body, and the two arms rotate together as one body from position E to position F. According to particular control means which are not detailed, the pressure sensor then acts and causes the suction cups to release the object to be manipulated.
Further, these control means reverse the operation of the drive means so as to reverse the operation of the arms and to bring the holder back to position D to pick up another object in another cycle.
1~752~5 ~s shown in Fig. 8, for example, the manipulator 1 of the present invention is applied to a press machine 200 having a mold 201 and a ram 202 positioned just above the mold 201, and manipulates an object 210a from the left hand side to the right hand side on the mold 201. The object 210a is pressed by moving down the ram 202 and is then manipulated from the mold 201 in the same manner as described above. Then, another object 210b is manipulated onto the mold 201 in the same manner as described above.
It will be apparent that, due to the functioning of the limited play means 50 of the present invention, at the ends of the locus through which the object is moved its direction of motion is altered sharply through nearly a right angle, for a short distance. In the described embodiment this is very useful for picking up and putting down objects. According to the present invention the construction of the manipulator is very simple, robust, cheap, and easy to service.
Another useful function of the limited play device of the present invention is as a protection again~t shocks.
It will be easily seen that if a sudden torque is applied to one of the arms, as for instance by an operator stumbling against the material holder, the limited play device 50 functions as a shock absorber and absorbs some of the impact on the machinery, which, if it were not cushioned, might cause serious damage to an inflexible structure.
Although the invention has been shown and described with respect to a preferred embodiment thereof, it should be understood that various changes and modifications could be made therein by a person skilled in the mechanical art, without departing from the scope of the invention, and therefore it is not intended that the description of the embodiment given above should limit the scope of protection sought, which scope is to be defined solely by the appended claims.
Claims (6)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A jointed manipulator comprising:
a body;
a first arm of which one end is pivotally mounted around a first axis to the body;
a first arm of which one end is pivotally mounted around a second axis to the other end of the first arm remote from the body;
a holder for holding material to be manipulated, which is pivotally mounted around a third axis to the other end of the second arm remote from the first arm;
a drive means for pivoting the first arm around the first axis with respect to the body;
a constraining means which constrains the holder to be in a fixed rotational orientation with respect to the body as the arms are pivoted by rotating the holder about the third axis with respect to the second arm;
and a coupling means, comprising:
a proportion maintaining means which pivots the second arm around the second axis with respect to the first arm, the amount of said pivoting bearing a proportional relation to the amount of pivoting provided by the drive means of the first arm around the first axis with respect to the body, a limited play means which allows the said proportional relation to alter within a certain limited range about the exactly proportional amount, when a twisting force of moment greater than a certain minimum moment is applied to the second arm, and a stop means which limits the movement of the second arm around the second axis with respect to the first arm within a certain range.
a body;
a first arm of which one end is pivotally mounted around a first axis to the body;
a first arm of which one end is pivotally mounted around a second axis to the other end of the first arm remote from the body;
a holder for holding material to be manipulated, which is pivotally mounted around a third axis to the other end of the second arm remote from the first arm;
a drive means for pivoting the first arm around the first axis with respect to the body;
a constraining means which constrains the holder to be in a fixed rotational orientation with respect to the body as the arms are pivoted by rotating the holder about the third axis with respect to the second arm;
and a coupling means, comprising:
a proportion maintaining means which pivots the second arm around the second axis with respect to the first arm, the amount of said pivoting bearing a proportional relation to the amount of pivoting provided by the drive means of the first arm around the first axis with respect to the body, a limited play means which allows the said proportional relation to alter within a certain limited range about the exactly proportional amount, when a twisting force of moment greater than a certain minimum moment is applied to the second arm, and a stop means which limits the movement of the second arm around the second axis with respect to the first arm within a certain range.
2. A manipulator according to claim 1, wherein the first, second, and third axes are parallel.
3. A manipulator according to claim 1 or claim 2, wherein the first and second arms are approximately the same length and the proportional relation between the amount of pivoting provided by the proportion maintaining means of the second arm around the second axis with respect to the first arm, and the amount of pivoting provided by the drive means of the first arm around the first axis with respect to the body, is approximately two to one.
4. A manipulator according to claim 3, wherein the constraining means comprises a third sprocket mounted around the first axis and fixed with respect to the body, fourth and fifth sprockets mounted around the second axis and fixed with respect to one another, a sixth sprocket mounted around the third axis and fixed with respect to the holder, an endless chain stretched around the third and fourth sprockets, and an endless chain stretched around the fifth and sixth sprockets, the product of the diameters of the fourth and the sixth sprockets being approximately equal to the product of the diameters of the third and the fifth sprockets, so that the sixth sprocket is approximately fixed in rotational orientation with respect to the body;
wherein the proportion maintaining means comprises a first sprocket mounted around the first axis, a second sprocket mounted around the second axis and fixed with respect to the second arm, and an endless chain stretched around the first and the second sprockets, said first sprocket being approximately twice the diameter of said second sprocket; wherein the limited play means comprises a stop arm which is mounted to rotate with the first sprocket and a pair of air cylinders and pistons which are supplied with compressed air and which opposedly engage the end of the stop arm and whose travel is limited so that the stop arm is fixed in position until it pushes against one of the pistons with force greater than a certain minimum force; and wherein the stop means comprises a plurality of stops mounted to the first arm and to the first sprocket in a manner to engage one another when the first arm has moved around the first sprocket to a certain extent in either direction.
wherein the proportion maintaining means comprises a first sprocket mounted around the first axis, a second sprocket mounted around the second axis and fixed with respect to the second arm, and an endless chain stretched around the first and the second sprockets, said first sprocket being approximately twice the diameter of said second sprocket; wherein the limited play means comprises a stop arm which is mounted to rotate with the first sprocket and a pair of air cylinders and pistons which are supplied with compressed air and which opposedly engage the end of the stop arm and whose travel is limited so that the stop arm is fixed in position until it pushes against one of the pistons with force greater than a certain minimum force; and wherein the stop means comprises a plurality of stops mounted to the first arm and to the first sprocket in a manner to engage one another when the first arm has moved around the first sprocket to a certain extent in either direction.
5. A manipulator according to claim 4, wherein the drive means comprises at least one fluid pressure cylinder.
6. A manipulator according to claim 5, wherein the holder is provided with suction cups which hold the material to be manipulated by vacuum suction.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6811678A JPS54159963A (en) | 1978-06-06 | 1978-06-06 | Articulated arm type manipulator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1075275A true CA1075275A (en) | 1980-04-08 |
Family
ID=13364439
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA313,064A Expired CA1075275A (en) | 1978-06-06 | 1978-10-11 | Jointed manipulator with controlled play indexing |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS54159963A (en) |
| AU (1) | AU509083B1 (en) |
| CA (1) | CA1075275A (en) |
| DE (1) | DE2842435A1 (en) |
| FR (1) | FR2427883A1 (en) |
| GB (1) | GB2022047A (en) |
| IT (2) | IT7920459V0 (en) |
| SE (1) | SE7810564L (en) |
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56142985U (en) * | 1980-03-24 | 1981-10-28 | ||
| IT8022968V0 (en) * | 1980-10-01 | 1980-10-01 | Norda Spa | AUTOMOBILE FOR FEEDING AND UNLOADING OF OPERATING MACHINES IN GENERAL. |
| US4433951A (en) * | 1981-02-13 | 1984-02-28 | Lam Research Corporation | Modular loadlock |
| JPS57199330U (en) * | 1981-06-12 | 1982-12-17 | ||
| JPH0328507Y2 (en) * | 1981-06-12 | 1991-06-19 | ||
| JPS5810491A (en) * | 1981-07-08 | 1983-01-21 | 株式会社東芝 | Robot device |
| CA1265091A (en) * | 1982-04-16 | 1990-01-30 | Richard Theodore Sahlin | Apparatus for loading and/or unloading industrial presses |
| GB2124173B (en) * | 1982-07-16 | 1986-05-14 | Planters Powergrind | Sheet material handling apparatus |
| JPS5959392A (en) * | 1982-09-29 | 1984-04-05 | メドマン株式会社 | Wrist device for industrial robot |
| FR2539661B1 (en) * | 1983-01-20 | 1986-07-04 | Citroen Sa | PARTS LOADER WITH SINGLE CONTROL MOTOR |
| IT8354029V0 (en) * | 1983-12-12 | 1983-12-12 | Comau Spa | MANIPULATOR ROBOT PARTICULARLY FOR THE TRANSFER OF SHEET ELEMENTS FROM A MOLDING STATION TO THE NEXT STATION OF A MOLDING LINE |
| CA1245246A (en) * | 1984-07-27 | 1988-11-22 | John Garin | Scara type manipulator apparatus |
| DE3511531A1 (en) * | 1985-03-29 | 1986-10-09 | Audi AG, 8070 Ingolstadt | Apparatus for relocating articles |
| GB8512056D0 (en) * | 1985-05-13 | 1985-06-19 | Universal Machine Intelligence | Robotic arm |
| US4728252A (en) * | 1986-08-22 | 1988-03-01 | Lam Research Corporation | Wafer transport mechanism |
| JPH02172689A (en) * | 1988-12-22 | 1990-07-04 | Ade Corp | Robot arm for converting rotary motion into linear motion |
| CH687370A5 (en) * | 1993-06-15 | 1996-11-29 | Robotec Consulting Ag | Knickarmvorrichtung for handling machines and industrial robots. |
| FR2818180B1 (en) * | 2000-12-20 | 2003-04-25 | Genus Technologies | GRIP DEVICE INTENDED TO BE MOUNTED ON A ROBOT ARM |
| DE10356941B4 (en) * | 2003-12-05 | 2008-03-20 | Gerhard Schubert Gmbh | vacuum slide |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB793898A (en) * | 1956-06-25 | 1958-04-23 | Seneca Falls Machine Co | Improvements in work-transfer mechanism for machine tools |
| US3010587A (en) * | 1957-09-20 | 1961-11-28 | Richard G Hollinger | Workpiece transfer mechanism |
| FR1431559A (en) * | 1965-04-22 | 1966-03-11 | Us Industries Inc | Device for handling objects |
| FR1545207A (en) * | 1966-11-23 | 1968-11-08 | Westinghouse Electric Corp | Manipulator device mounted remotely from the operator |
| GB1244940A (en) * | 1969-03-31 | 1971-09-02 | Aida Tekkosho Kk | An article transfer apparatus |
| JPS4726449U (en) * | 1971-04-16 | 1972-11-25 | ||
| US3985238A (en) * | 1973-03-17 | 1976-10-12 | Daikin Kogyo Co., Ltd. | Industrial robot |
-
1978
- 1978-06-06 JP JP6811678A patent/JPS54159963A/en active Granted
- 1978-09-20 GB GB7837534A patent/GB2022047A/en not_active Withdrawn
- 1978-09-29 DE DE19782842435 patent/DE2842435A1/en not_active Ceased
- 1978-10-10 SE SE7810564A patent/SE7810564L/en unknown
- 1978-10-11 CA CA313,064A patent/CA1075275A/en not_active Expired
- 1978-10-18 AU AU40851/78A patent/AU509083B1/en not_active Expired
- 1978-11-27 FR FR7833491A patent/FR2427883A1/en active Pending
-
1979
- 1979-01-10 IT IT7920459U patent/IT7920459V0/en unknown
- 1979-01-10 IT IT7919182A patent/IT7919182A0/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| DE2842435A1 (en) | 1979-12-13 |
| JPS5630158B2 (en) | 1981-07-13 |
| IT7919182A0 (en) | 1979-01-10 |
| GB2022047A (en) | 1979-12-12 |
| FR2427883A1 (en) | 1980-01-04 |
| IT7920459V0 (en) | 1979-01-10 |
| AU509083B1 (en) | 1980-04-17 |
| JPS54159963A (en) | 1979-12-18 |
| SE7810564L (en) | 1979-12-07 |
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Legal Events
| Date | Code | Title | Description |
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| MKEX | Expiry |