CN111936277A

CN111936277A - Apparatus and method for a robot

Info

Publication number: CN111936277A
Application number: CN201980024788.0A
Authority: CN
Inventors: 维萨·希尔沃宁; 维尔·希尔沃宁
Original assignee: Masnova Ltd
Current assignee: Masnova Ltd
Priority date: 2018-02-06
Filing date: 2019-02-06
Publication date: 2020-11-13
Anticipated expiration: 2039-02-06
Also published as: FI20185101A1; CN111936277B; WO2019155121A1; FI130255B

Abstract

The present invention relates to an apparatus and method for increasing the stroke speed of a robot by rapidly adjusting the stroke length and by balancing the robot. The problem with increasing the stroke speed is the vibrations, which may render the stroke inaccurate and may damage the robot in question. In the present invention, the apparatus comprises: a dual crankshaft (106); a flywheel (108) connected to the crankshaft (106); two motors (102, 104) for adjusting the stroke length by adjusting the position of the crankshaft relative to the flywheel, wherein one motor is for rotating the crankshaft and the other motor is for rotating the flywheel.

Description

Apparatus and method for a robot

Technical Field

The present invention relates generally to apparatus and methods for robot equipment and, more particularly, to apparatus and methods for adjusting stroke length during operating speeds and for balancing the Z-axis of robot equipment at high speeds.

Background

The robot may be programmed to provide a stroke or press along the Z-axis. However, adjusting the stroke length may be difficult to perform. Typically, the robot has to be stopped when adjusting the stroke length, which takes time.

The strokes along the Z-axis are typically arranged sinusoidally so that the percussion device performs a reciprocating movement. Unfortunately, it is well known that this can wear motors and machinery in the robot, which can shorten the life cycle of the robot or at least cause costs due to repair or replacement of worn parts.

The stroke speed of the robot may be difficult to increase because the vibration caused by the weight of the impact ram increases when attempting to increase the stroke speed. The vibrations degrade stroke accuracy and may damage the robot.

Attempts have been made to solve this problem by increasing the weight of the apparatus to balance the ram, but in many cases these solutions result in a very heavy apparatus which may also require a lot of space. For example, in clean indoor environments where there is a lack of space, it is particularly impractical to use such large and heavy robots therein.

Disclosure of Invention

The object of the present invention is to implement a solution which makes it possible to eliminate the aforementioned drawbacks of the prior art. In particular, the invention implies a solution to how to increase the impact speed of the robot.

The object of the invention is achieved by the features disclosed in the independent patent claims.

The device for increasing the impact speed of a robot according to the invention is characterized by the features of claim 1.

According to an embodiment of the present invention, an apparatus for increasing impact speed of a robot device includes: a double crankshaft; a flywheel connected to the crankshaft; two motors for adjusting a stroke length by adjusting a position of the crankshaft with respect to the flywheel, wherein one motor is for rotating the crankshaft and the other motor is for rotating the flywheel.

In this embodiment, the stroke speed may be increased by: wherein the stroke length can be adjusted at the operating speed without stopping the robot for stroke length adjustment.

In one embodiment, the apparatus further comprises: a balance weight for balancing the Z axis such that the balance weight is connected in one crankshaft and a movable weight of the Z axis is connected in the other crankshaft, and wherein the phase difference between the crankshafts is 180 degrees. In this embodiment, the stroke speed of the robot apparatus can be increased by a scheme in which the vibration caused by the inertia of the movable mass is reduced by the balance weight.

In one embodiment, the mass of the balancing weight is selected to be the same as the mass of the movable weight. This feature may further minimize vibration and help increase stroke speed.

In one embodiment, the shape of the balancing weight is cylindrical, so that its center of gravity can be arranged on the same vertical axis as the movable weight. In this way, it is possible to minimize lateral vibration caused by moving the counterweight at high speed.

In another embodiment, at least one tension spring is arranged on the Z-axis for lightening the weight of the movable weight and/or the balancing weight. In this feature, the static weight of the robot in the Z-axis can be compensated.

In one embodiment, the horizontal arm of the robot includes an adjustable balancing weight. This feature may enable the horizontal arms of the robot to be balanced as well, in order to avoid or at least minimize vibrations caused by the movement of these arms.

The method according to the invention for increasing the impact speed of a robot is characterized by the features of claim 7.

According to an embodiment of the invention, the method for increasing the impact speed of a robot comprising the device according to the invention comprises at least the following steps: the stroke length is adjusted by adjusting the position of the crankshaft relative to the flywheel.

In one embodiment, the method further comprises the steps of: arranging the balance weight in connection with one crankshaft and the movable weight of the Z axis in the other crankshaft and arranging the phase difference between the crankshafts to be 180 deg..

Some preferred embodiments of the invention are described in the dependent claims.

Significant advantages can be achieved with the present invention compared to prior art solutions. The device according to the invention with double crankshafts can be used for fast linear movements. Linear rotational movement may eliminate or at least reduce motor and mechanical wear of the stroke system in the robot as compared to reciprocating movement. In addition, the acceleration and deceleration of the two ends of the linear movement can be optimized with respect to the speed. In this way, the stroke speed of the robot can be increased.

By using the device according to the invention, the stroke length of the robot can be adjusted in each round and at full speed. This may enable faster operation and easy programming of the stroke length function. Furthermore, the stroke length can be steplessly adjusted from zero to the maximum stroke length. The device according to the invention also makes it possible to achieve the starting and ending points of the stroke length.

The arrangement according to the invention in a robot may be small and compact, which may mean that a robot with the arrangement in question may be much faster than a normal robot, e.g. ten times faster, up to a stroke speed of even 360 strokes rpm/min. However, the robot with the device in question may not need a large space itself, but it may be able to adapt to the space of the average robot. The robot with the device in question can be used for various purposes and can be used under various conditions, such as clean room conditions.

The expression "high speed" herein refers to crankshaft speed, which may be 300rpm/min or more.

The expression "number" means herein any positive integer starting from one (1), such as one, two or three.

The terms "a" and "an," as used herein, are defined as one or more than one.

Drawings

The invention is described in more detail below with reference to the attached drawing figures, wherein:

figure 1 depicts a perspective view of an apparatus according to an embodiment of the invention in a robot,

figure 2a depicts a perspective view of an apparatus according to an embodiment of the invention in a lower stroke position in a robot,

figure 2b depicts a perspective view of the device of figure 2a in a mid-stroke or zero stroke length position,

figure 2c depicts a perspective view of the device of figure 2a in the upper stroke (up, up) position,

figure 3a depicts a front view of a dual crankshaft and flywheel in a lower stroke position according to an embodiment of the present invention in a robot,

figure 3b depicts a front view of the dual crankshaft and flywheel of figure 3a in a mid-stroke or zero stroke length position,

figure 3c depicts a front view of the dual crankshaft and flywheel of figure 3a in an upper stroke position,

figure 4a depicts a perspective view of figure 3a,

figure 4b depicts a perspective view of figure 3b,

figure 4c depicts a perspective view of figure 3c,

fig. 5a and 5b depict adjustable balance weights in other arms of a robot, and fig. 6 is a method according to an embodiment of the invention.

Detailed Description

In the drawings herein, a unique feature receives a unique reference numeral, while in more than one drawing the same feature receives the same reference numeral throughout. Furthermore, certain directional terms may be used, such as "upper," lower, "" top, "" bottom, "" left, "" right, "" inner, "" outer, "" inner, "and" outer. These terms are generally for ease of reference and should be understood as such unless a particular embodiment requires otherwise.

Fig. 1 depicts a perspective view of an apparatus according to an embodiment of the present invention in a robot device. The apparatus comprises two

motors

102 and 104 for the Z-axis of the robot in question, a double crankshaft 106 and a flywheel 108 connected to the crankshaft 106. The

motors

102 and 104 are used to adjust the stroke length by adjusting the position of the crankshaft 106 relative to the flywheel 108 in such a way that one motor is used to rotate the crankshaft 106 and the other motor is used to rotate the flywheel 108, as described in more detail below.

In one embodiment, the apparatus further includes a balancing weight 110 for balancing the Z axis. The movable counterweight 114 in the Z-axis comprises other components of the robot in question, such as arm units for the X-axis and the Y-axis and motor units for moving the arm units in question.

The balance weight 110 is connected in one crankshaft and the movable weight 114 is connected in the other crankshaft. Flywheels 108 are preferably disposed at and between both ends of crankshaft 106, as will be described in more detail below.

In one embodiment, the mass of the balance weight 110 is selected to be the same as the weight of the movable weight 114. The balance weight 110 is advantageously cylindrical in shape so that its center of gravity can be disposed on the same vertical axis as the movable weight.

According to an embodiment, at least one tension spring 112 is arranged on the Z-axis for lightening the movable weight. It will be appreciated by those skilled in the art that the device may comprise more than one tension spring and that the characteristics of the springs may be different. A tension spring is connected from its upper end to the upper part of the robot, preferably above the balancing weight, and from its lower part to the movable weight.

Fig. 2a depicts a front view of an arrangement according to an embodiment of the invention in a lower stroke position in a robot, fig. 2b depicts the arrangement of fig. 2a in a mid-stroke position or zero stroke length position, and fig. 2c depicts the arrangement of fig. 2a in an upper stroke position.

As seen in fig. 2a to 2c, a balance weight 110 is connected in one crankshaft 106a and a movable weight is connected in the other crankshaft 106 b. In one embodiment, the phase difference between the balance weight 110 and said movable weight 114 is 180 ° degrees, such that when the movable weight is in the lower stroke position, the balance weight is in the upper position, and vice versa.

Fig. 3a depicts a front view of a dual crankshaft and flywheel in a lower stroke position according to an embodiment of the present invention in a robot, fig. 3b depicts the dual crankshaft and flywheel of fig. 3a in a mid-stroke position or zero stroke length position, and fig. 3c depicts the dual crankshaft and flywheel of fig. 3a in an upper stroke position. Fig. 4a to 4c depict perspective views of fig. 3a to 3c, respectively.

In one embodiment, the stroke length is adjusted by adjusting the position of the

crankshafts

106a, 106b relative to the flywheel 108. According to this embodiment, the motors (not shown in fig. 3 a-3 c, 4 a-4 c) are arranged to rotate the flywheel 108 and the

crankshafts

106a, 106b independently, such that one motor rotates the flywheel 108 and the other motor rotates the

crankshafts

106a, 106 b.

As can be seen in fig. 3a and 3c and fig. 4a and 4c, the

crankshafts

106a, 106b are arranged in an outermost position with respect to the position of the flywheel 108, which means the longest stroke. In other words, when the crankshaft is directed straight downwards, the end of the flywheel connected to the crankshaft is also directed downwards, and when the crankshaft is directed straight upwards, the end of the flywheel in question is also directed upwards.

The zero stroke length position can be seen in fig. 3c and 4 c. In this position, the

crankshafts

106a, 106b are rotated 180 degrees from a maximum stroke position to an innermost position between the flywheels. In this case, the stroke length is zero when the motor rotates the flywheel and the crankshaft.

By adjusting the angle between the flywheel and the crankshaft between zero and 180 degrees, the stroke length can be adjusted continuously between zero and a maximum value.

Fig. 5a and 5b depict adjustable balancing weights 402 in

other arms

404a, 404b of the robot. Typically, the robot includes at least two arms coupled together to cover the x-y axis. The arms move to different positions relative to each other. According to the invention, a balancing weight 402 is arranged on the horizontal axis of the

arms

404a, 404b to compensate the mass of the arms with respect to the working axis.

The balance weight 402 is arranged to be movable on a horizontal axis, the balance weight 402 being moved to the following positions when the

arms

404a, 404b are moved: in this position, the weight of the arm is in equilibrium from the perspective of the working axis 406.

Fig. 6 is a flow chart of a method according to an embodiment of the invention. At step 502, a balance weight is arranged in connection with one crankshaft and a movable weight is arranged in connection with another crankshaft. At step 504, the crankshafts are arranged to have a phase difference of 180 ° such that when the movable counterweight moves downward, the balance weight moves upward, and vice versa.

Another embodiment includes step 506, wherein a stroke length of the robot is adjusted by adjusting a position of the crankshaft relative to the flywheel. This step is repeated while the impact program is run using the robot.

The scope of the invention is to be determined by the appended claims and their equivalents. The skilled person will again recognise the fact that the explicitly disclosed embodiments are constructed for illustrative purposes only, and the scope will cover other embodiments, combinations of embodiments, manufacturing processes and equivalents that are better suited for each particular use case of the invention.

Claims

1. Apparatus for increasing the impact velocity of a robotic device, comprising:

-a double crankshaft (106),

a flywheel (108) connected to the crankshaft (106),

-two motors (102, 104) for adjusting the stroke length,

characterized in that one motor is adapted to rotate the crankshaft (106) and the other motor is adapted to rotate the flywheel (108) for adjusting the angle between the flywheel (108) and the crankshaft (106) between substantially zero and 180 degrees.

2. The apparatus of claim 1, wherein the apparatus further comprises a balance weight (110) for balancing the Z-axis, such that the balance weight (110) is connected in one crankshaft (106a) and the movable weight (114) of the Z-axis is connected in the other crankshaft (106b), and wherein the phase difference between the crankshafts is 180 ° degrees.

3. The apparatus of claim 2, wherein the mass of the balancing weight (110) corresponds to the mass of the movable weight (114).

4. The device according to any one of claims 2 to 3, wherein the shape of the balancing weight (110) is cylindrical, such that the center of gravity of the balancing weight can be arranged on the same vertical axis as the movable weight (114).

5. The device according to any preceding claim, wherein at least one tension spring (112) is arranged on the Z-axis for lightening the movable weight (114).

6. An apparatus according to any preceding claim, wherein the horizontal arm of the robot comprises at least one adjustable balancing weight.

7. Method for increasing the impact speed of a robot comprising a device according to any of claims 1 to 6, comprising at least the following steps:

-adjusting a stroke length (506) by adjusting a position of the crankshaft relative to the flywheel.

8. The method of claim 7, further comprising the steps of:

-arranging the balancing weights in connection with one crankshaft and the movable weights of the Z-axis in the other crankshaft (502);

-arranging a phase difference between the crankshafts to be 180 ° degrees (504).