Device and method for checking position of rolling ball in ball socket

Abstract

The invention provides a device and method for checking the position of a rolling ball in a ball socket, and the device comprises a fixed table, a bottom plate and a support, the fixed table and the support are disposed on the bottom plate, and the upper end of the support extends to the upper part of the fixed table and is provided with an image collection module; the fixing table is used for placing a ball socket and limiting and fixing the ball socket; the image acquisition module is used for shooting a ball socket arranged on the fixed table so as to obtain coordinate positions of three rolling balls on the ball socket, obtaining a coordinate position of a ball center of a virtual ball of the ball socket through the coordinate positions of the three rolling balls, comparing the coordinate position of the ball center of the virtual ball with the coordinate position of a theoretical ball center corresponding to the ball socket, and obtaining a comparison result of the coordinate position of the ball center of the virtual ball and the coordinate position of the theoretical ball center; whether the positions of the three rolling balls on the ball socket meet preset requirements or not is judged; according to the method, the accuracy of rolling ball position inspection is ensured, and the inaccuracy caused by manual inspection is avoided.

Description

Technical Field

[0001] The invention relates to the field of coordinate measurement technology, and in particular to a device and method for calibrating the position of a rolling ball in a ball socket. Background Art

[0002] In the prior art, both the outer and inner sides of the ball socket for accommodating the pulley ball are spherical in shape. In order to ensure that the pulley ball can roll smoothly in all directions in the ball socket, the positions of the three rolling balls in the ball socket need to be precisely set. When the positions of the three rolling balls in the ball socket deviate and do not meet the set requirements, the subsequent rolling of the pulley ball may not achieve the ideal smoothness, affecting the feel of use.

[0003] For the above problem, the existing inspection method is usually to put the pulley ball into the ball socket, manually roll the pulley ball, and judge whether the pulley ball rolls smoothly by manual feeling. This method is difficult to ensure the accuracy of each inspection.

[0004] In view of this, overcoming the defects of the prior art is an urgent problem to be solved in the field of this technology. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to accurately check the accuracy of the position of the rolling ball in the ball socket.

[0006] The present invention adopts the following technical solution:

[0007] In a first aspect, a device for checking the position of a rolling ball in a ball socket is provided, comprising: a fixed platform 1, a base plate 2, a bracket 3 and an image acquisition module 4, wherein:

[0008] The fixing platform 1 and the bracket 3 are both arranged on the bottom plate 2, the upper end of the bracket 3 extends to the upper position of the fixing platform 1, and the image acquisition module 4 is arranged on the upper end of the bracket 3;

[0009] The fixed platform 1 is used to place the ball socket 5 and limit and fix the ball socket 5. When the ball socket 5 is set on the fixed platform 1, the plane where the three rolling balls 51 on the ball socket 5 are located is parallel to the horizontal plane; the image acquisition module 4 is used to shoot the ball socket 5 set on the fixed platform 1, so as to obtain the coordinate positions of the three rolling balls 51 on the ball socket 5, and obtain the coordinate position of the center of the virtual ball of the ball socket 5 through the coordinate positions of the three rolling balls 51, and compare the coordinate position of the center of the virtual ball with the coordinate position of the theoretical center of the ball socket 5, so as to judge whether the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements.

[0010] Preferably, the fixing platform 1 comprises a base 11, a limiting groove 12 and at least two threaded holes 13, wherein:

[0011] The limiting groove 12 is located at the upper end of the base 11; the two threaded holes 13 are both provided on the upper end surface of the base 11 and are respectively located at two sides of the limiting groove 12;

[0012] The limiting groove 12 is used to accommodate the ball socket 5, and the screw hole platform 54 on one side of the ball socket 5 corresponds to one of the threaded holes 13 and is fixed by screws. The screw hole platform 54 on the other side of the ball socket 5 corresponds to the other threaded hole 13 and is fixed by screws.

[0013] Preferably, the bottom surface of the limiting groove 12 is a matching inclined surface 121, and the angle between the matching inclined surface 121 and the horizontal plane is a first preset angle; the angle between the matching inclined surface 52 on the outer surface of the ball socket 5 and the plane where the three rolling balls 51 are located is a second preset angle; the first preset angle and the second preset angle are the same;

[0014] When the ball socket 5 is located in the limiting groove 12 , the matching inclined surface 121 fits with the matching inclined surface 52 , thereby ensuring that when the ball socket 5 is limited and fixed in the limiting groove 12 , the plane where the three rolling balls 51 are located is parallel to the horizontal plane.

[0015] Preferably, a positioning pin 122 is further provided on the matching bevel 121 , and when the ball socket 5 is located in the limiting groove 12 and the matching bevel 121 fits with the mating bevel 52 , the positioning pin 122 is inserted into the positioning hole 53 on the mating bevel 52 .

[0016] Preferably, the angle between the upper end surface of the base 11 and the horizontal plane is the first preset angle.

[0017] Preferably, the image acquisition module 4 is located directly above the ball socket 5 .

[0018] In a second aspect, a method for verifying the position of a rolling ball in a ball socket is provided, which is used in a device for verifying the position of a rolling ball in a ball socket, comprising:

[0019] The ball socket 5 is fixed so that the plane where the three rolling balls 51 on the ball socket 5 are located is parallel to the horizontal plane, and the ball socket 5 is photographed directly above the ball socket 5 to obtain a picture of the ball socket;

[0020] Obtaining coordinate positions of three rolling balls 51 respectively according to the ball and socket photographs;

[0021] The coordinate position of the center of the virtual ball in the socket 5 is obtained through the coordinate positions of the three rolling balls 51;

[0022] The coordinate position of the center of the virtual ball is compared with the coordinate position of the theoretical center of the ball socket 5 to determine whether the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements.

[0023] Preferably, the step of obtaining the coordinate position of the center of the virtual ball of the socket 5 through the coordinate positions of the three rolling balls 51 specifically includes:

[0024] The average value of the horizontal axis coordinates of the centers of the three rolling balls 51 is used as the horizontal axis coordinate of the center of the virtual ball, and the average value of the vertical axis coordinates of the centers of the three rolling balls 51 is used as the vertical axis coordinate of the center of the virtual ball;

[0025] Obtaining the projection position of any rolling ball 51 on the horizontal plane, and the projection position of the center of the virtual ball on the horizontal plane;

[0026] Obtaining a projection distance between the projection position of any rolling ball 51 and the projection position of the center of the virtual ball;

[0027] The height difference between the center of the virtual ball and the plane where the three rolling balls 51 are located is obtained according to the projection distance, the inner radius of the ball socket 5 and the radius of the rolling ball 51, and the height difference is used as the vertical axis coordinate of the center of the virtual ball.

[0028] Preferably, the coordinate position of the center of the virtual ball is compared with the coordinate position of the theoretical center of the ball socket 5 to determine whether the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements, which specifically includes:

[0029] Obtain the horizontal axis coordinate difference between the horizontal axis coordinate of the center of the virtual sphere and the horizontal axis coordinate of the center of the theoretical sphere;

[0030] Obtain the difference between the longitudinal coordinate of the center of the virtual sphere and the longitudinal coordinate of the center of the theoretical sphere;

[0031] Obtain the vertical axis coordinate difference between the vertical axis coordinate of the center of the virtual sphere and the vertical axis coordinate of the center of the theoretical sphere;

[0032] When the horizontal axis coordinate difference, the vertical axis coordinate difference and the vertical axis coordinate difference are all less than or equal to the preset difference, the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements;

[0033] When one or more of the horizontal axis coordinate difference, the vertical axis coordinate difference and the vertical axis coordinate difference is greater than the preset difference, the positions of the three rolling balls 51 on the ball socket 5 do not meet the preset requirements.

[0034] Preferably, the step of respectively acquiring the coordinate positions of the three rolling balls 51 according to the ball and socket photographs specifically includes:

[0035] Obtain pixel positions of the centers of the three rolling balls 51 in the ball-and-socket photo, and obtain coordinate positions of the centers of the three rolling balls 51 in the industrial camera coordinate system respectively;

[0036] The industrial camera coordinate system is transformed into a special tooling coordinate system to obtain the coordinate positions of the centers of the three rolling balls 51 in the special tooling coordinate system.

[0037] The present invention provides a device and method for checking the position of a rolling ball in a ball socket, comprising: a fixed platform 1, a bottom plate 2 and a bracket 3, wherein the fixed platform 1 and the bracket 3 are both arranged on the bottom plate 2, and the upper end of the bracket 3 extends to the upper position of the fixed platform 1 and is provided with an image acquisition module 4; the fixed platform 1 is used to place a ball socket 5 and limit and fix the ball socket 5; the image acquisition module 4 is used to shoot the ball socket 5 arranged on the fixed platform 1 to obtain the coordinate positions of three rolling balls 51 on the ball socket 5, obtain the coordinate position of the center of a virtual ball of the ball socket 5 through the coordinate positions of the three rolling balls 51, compare the coordinate position of the center of the virtual ball with the coordinate position of the theoretical center of the ball socket 5 corresponding to the ball socket 5, so as to judge whether the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements; the above method ensures the accuracy of the inspection of the position of the rolling ball 51 and avoids the inaccuracy caused by manual inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 is a schematic diagram of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0040] Figure 2 It is a schematic structural diagram of a ball socket of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0041] Figure 3 It is a schematic diagram of the structural components of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0042] Figure 4 It is a partial structural schematic diagram of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0043] Figure 5 It is a schematic structural diagram of another ball socket of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0044] Figure 6 It is a partial structural schematic diagram of another device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0045] Figure 7 It is a structural schematic diagram of a ball socket of another device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0046] Figure 8 is a method flow chart of a method for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0047] Fig. 9 is a top view of a ball socket of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0048] Fig.10 is a cross-sectional view of a ball socket of a device for checking the position of a rolling ball in a ball socket provided by an embodiment of the present invention;

[0049] The diagram numbers are as follows:

[0050] The fixing platform 1, the base 11, the limiting groove 12, the matching inclined surface 121, the positioning pin 122, the threaded hole 13, the bottom plate 2, the bracket 3, the image acquisition module 4, the ball socket 5, the rolling ball 51, the matching inclined surface 52, the positioning hole 53, and the screw hole platform 54. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0052] In the description of the present invention, it is necessary to understand that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

[0053] In the description of the present invention, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, the meaning of "multiple" is two or more. In addition, for example, the same type of nouns may be described as two independent individuals by adding "A" and "B" at the end. In this case, the corresponding features defined as "A" and "B" are only used to distinguish the same type of individuals for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features.

[0054] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity, i.e., the limitations of the measurement system.

[0055] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as open inclusion, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "examples", "specific examples" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner, that is, although they may be carried in the embodiments or examples of the above terms due to reasons such as the order and position of appearance, it is not limited to that they can be carried in combination by one embodiment or example.

[0056] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0057] Embodiment 1:

[0058] Embodiment 1 of the present invention provides a device for checking the position of a rolling ball in a ball socket, such as Figure 1 and Figure 2 As shown, it includes: a fixing platform 1, a base plate 2, a bracket 3 and an image acquisition module 4, wherein:

[0059] The fixing platform 1 and the bracket 3 are both arranged on the bottom plate 2 . The upper end of the bracket 3 extends to a position above the fixing platform 1 . The image acquisition module 4 is arranged on the upper end of the bracket 3 .

[0060] The fixed platform 1 is used to place the ball socket 5 and limit and fix the ball socket 5. When the ball socket 5 is set on the fixed platform 1, the plane where the three rolling balls 51 on the ball socket 5 are located is parallel to the horizontal plane; the image acquisition module 4 is used to shoot the ball socket 5 set on the fixed platform 1, so as to obtain the coordinate positions of the three rolling balls 51 on the ball socket 5, and obtain the coordinate position of the center of the virtual ball of the ball socket 5 through the coordinate positions of the three rolling balls 51, and compare the coordinate position of the center of the virtual ball with the coordinate position of the theoretical center of the ball socket 5, so as to judge whether the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements.

[0061] Wherein, the image acquisition module 4 can be an industrial camera.

[0062] In this embodiment, when the ball socket 5 is set on the fixed platform 1, the inner side of the ball socket 5 faces upward and the outer side of the ball socket 5 faces downward. The image acquisition module 4 is located directly above the ball socket 5 and shoots the inner side of the ball socket 5 in a vertically downward direction.

[0063] In this embodiment, the image acquisition module 4 is located directly above the ball socket 5, wherein the virtual ball is not an actual physical structure existing in the ball socket 5, but a hypothetical structure used for the convenience of description; since the plane passed by the three rolling balls 51 in the ball socket 5 is parallel to the horizontal plane, when the three rolling balls 51 are photographed from the vertical direction, the position of the rolling balls 51 in the photo will hardly be affected by the vertical axis projection position error, and the horizontal axis coordinate and the vertical axis coordinate of the rolling ball 51 in the photo can be directly regarded as the horizontal axis coordinate and the vertical axis coordinate of the rolling ball 51 in the three-dimensional coordinate system.

[0064] After the horizontal axis coordinates and the vertical axis coordinates of each rolling ball 51 are acquired, the coordinates of the center of the virtual ball in the ball socket 5 can be calculated according to the horizontal axis coordinates and the vertical axis coordinates of each rolling ball 51 .

[0065] In this embodiment, the theoretical ball center is the ball center corresponding to the inner side of the ball socket 5 when the positions of the three rolling balls 51 are accurate. Taking the theoretical ball center as a standard, the theoretical ball center is compared with the ball center of the virtual ball obtained in the subsequent measurement to know whether the ball center of the virtual ball meets the requirements. Since the ball center of the virtual ball is obtained based on the coordinate positions of the three rolling balls 51, when the ball center of the virtual ball meets the requirements, it means that the coordinate positions of the three rolling balls 51 meet the requirements. When the ball center of the virtual ball does not meet the requirements, it means that the coordinate positions of the three rolling balls 51 do not meet the requirements.

[0066] Figure 3 The device for verifying the position of the rolling ball in the ball socket may include various components, including an image acquisition module 4, a computing module, a camera bracket, special tooling and other installation accessories.

[0067] In this embodiment, since the fixing platform 1 needs to fix and limit the ball socket 5, this embodiment provides a structural design of the fixing platform 1 as follows: Figure 4 and Figure 5 As shown, the fixing platform 1 includes a base 11, a limiting groove 12 and at least two threaded holes 13, wherein: the limiting groove 12 is located at the middle position of the upper end of the base 11; the two threaded holes 13 are both arranged on the upper end surface of the base 11, and are respectively located at both sides of the limiting groove 12; the limiting groove 12 is used to accommodate the ball socket 5, the screw hole platform 54 on one side of the ball socket 5 corresponds to one of the threaded holes 13, and is fixed by screws, and the screw hole platform 54 on the other side of the ball socket 5 corresponds to the other threaded hole 13, and is fixed by screws.

[0068] In this embodiment, the limiting groove 12 is used to accommodate the lower end portion of the ball socket 5, but since the ball socket 5 cannot be stably limited and fixed by the limiting groove 12 alone, it is also necessary to fix it by screws. In this embodiment, a screw hole platform 54 is respectively provided on both sides of the ball socket 5, and the screw hole platform 54 can be used to fix the ball socket 5, that is, two threaded holes 13 are provided on the fixing platform 1, one of the threaded holes 13 is located on one side of the limiting groove 12, corresponding to one of the screw hole platforms 54 on the ball socket 5; the other threaded hole 13 is located on the other side of the limiting groove 12, corresponding to the other screw hole platform 54 on the ball socket 5, and the ball socket 5 is fixed on the fixing platform 1 by the cooperation of screws.

[0069] Furthermore, since the lower surface of the ball socket 5 is in an arc shape, even if the ball socket 5 is set in the limiting groove 12, the arc surface of the lower surface of the ball socket 5 and the inner surface of the limiting groove 12 are still prone to relative movement. Even if they are fixed by screws, the positional relationship between the ball socket 5 and the limiting groove 12 cannot be guaranteed to be accurate, and the plane where the three rolling balls 51 are located cannot be guaranteed to be parallel to the horizontal plane; and when the ball socket 5 is actually fixed in the limiting groove 12, there is no relative reference object during the fixing process to ensure that the ball socket 5 is placed correctly, so that the plane where the three rolling balls 51 are located is parallel to the horizontal plane, resulting in a relatively troublesome fixing process of the ball socket 5 on the fixing seat, and it is also prone to errors. Therefore, this embodiment also involves the following designs:

[0070] like Figure 5-Figure 7As shown, the bottom surface of the limiting groove 12 is a matching inclined surface 121, and the angle between the matching inclined surface 121 and the horizontal plane is a first preset angle; the angle between the matching inclined surface 52 on the outer surface of the ball socket 5 and the plane where the three rolling balls 51 are located is a second preset angle; the first preset angle and the second preset angle are the same. When the ball socket 5 is located in the limiting groove 12, the matching inclined surface 121 and the matching inclined surface 52 are in contact with each other, thereby ensuring that when the ball socket 5 is fixed in the limiting groove 12, the plane where the three rolling balls 51 are located is parallel to the horizontal plane.

[0071] In this embodiment, a positioning hole 53 is provided on the ball socket 5, and the peripheral position of the positioning hole 53 on the outer side surface of the ball socket 5 is a plane, which is the matching bevel 52. This part of the structure on the ball socket 5 is used to match with other structural parts after leaving the factory. In this embodiment, the positioning hole 53 and the matching bevel 52 are used to fix the ball socket 5. Since the matching bevel 52 is a plane, it is easier to refer to and limit than the arc-shaped outer side surface of the ball socket 5. By fitting the matching bevel 121 with the matching bevel 52, and matching the screw hole platforms 54 on both sides of the ball socket 5 with the two threaded holes 13 on the fixing platform 1 respectively, at this time, the plane where the three rolling balls 51 are located and the matching bevel 121 are located. The angle between them is also the second preset angle. Since the angle between the matching bevel 121 and the horizontal plane is the first preset angle, the first preset angle is the same as the second preset angle. Therefore, at this time, the plane where the three rolling balls 51 are located is parallel to the horizontal plane. Therefore, by arranging the matching bevel 121 in the limit groove 12, the position state of the ball socket 5 is easier to confirm. As long as the matching bevel 121 and the matching bevel 52 are fitted together, and the screw hole platforms 54 on both sides of the ball socket 5 are respectively matched with the two threaded holes 13 on the fixing platform 1, it can be ensured that the plane where the three rolling balls 51 are located is parallel to the horizontal plane. There is no need for technicians to spend extra energy to confirm the position state of the three rolling balls 51 in the ball socket 5, thereby improving the measurement efficiency.

[0072] like Figure 6 and Figure 7 As shown, a positioning pin 122 is also provided on the matching bevel 121 . When the ball socket 5 is located in the limiting groove 12 and the matching bevel 121 fits with the matching bevel 52 , the positioning pin 122 is inserted into the positioning hole 53 on the matching bevel 52 .

[0073] The positioning pin 122 is used to limit the ball socket 5 when the matching bevel 121 and the matching bevel 52 are in contact with each other, so that it is convenient for technical personnel in this field to match and fix the screw hole base 54 of the ball socket 5 and the threaded hole 13 on the fixing platform 1. If there is no positioning pin 122, when the screw hole base 54 of the ball socket 5 and the threaded hole 13 on the fixing platform 1 are matched and fixed, it is still necessary to manually maintain the position of the ball socket 5. Therefore, the positioning pin 122 further facilitates the operation of limiting and fixing the ball socket 5.

[0074] Embodiment 2:

[0075] This embodiment provides a method for checking the position of a rolling ball in a ball socket on the basis of the embodiment 1, which is used in the device for checking the position of a rolling ball in a ball socket described in the embodiment 1. Figure 8 As shown, including:

[0076] In step 101, the ball socket 5 is fixed so that the plane where the three rolling balls 51 on the ball socket 5 are located is parallel to the horizontal plane, and the ball socket 5 is photographed directly above the ball socket 5 to obtain a photo of the ball socket.

[0077] In step 102, the coordinate positions of the three rolling balls 51 are respectively obtained according to the ball and socket photographs.

[0078] In this embodiment, the pixel positions of the centers of the three rolling balls 51 in the ball socket photo are obtained, and the coordinate positions of the centers of the three rolling balls 51 in the industrial camera coordinate system are obtained respectively; the industrial camera coordinate system is transformed into a special tooling coordinate system to obtain the coordinate positions of the centers of the three rolling balls 51 in the special tooling coordinate system.

[0079] In step 103 , the coordinate position of the center of the virtual ball in the socket 5 is obtained through the coordinate positions of the three rolling balls 51 .

[0080] The average value of the horizontal axis coordinates of the centers of the three rolling balls 51 is used as the horizontal axis coordinate of the center of the virtual ball, and the average value of the vertical axis coordinates of the centers of the three rolling balls 51 is used as the vertical axis coordinate of the center of the virtual ball.

[0081] The coordinates of the three rolling balls 51 are (p 1x ,p 1y )、(p 2x ,p 2y ) and (p 3x ,p 3y ), the line connecting the centers of the three rolling balls 51 forms an equilateral triangle, the center point of the equilateral triangle is the center of the virtual ball, so the coordinates of the center of the virtual ball (p ox ,p oy ) is calculated as follows:

[0082]

[0083] Obtain the projection position of any rolling ball 51 on the horizontal plane, and the projection position of the center of the virtual ball on the horizontal plane; obtain the projection distance between the projection position of any rolling ball 51 and the projection position of the center of the virtual ball; obtain the height difference between the center of the virtual ball and the plane where the three rolling balls 51 are located according to the projection distance, the inner radius of the socket 5 and the radius of the rolling ball 51, and use the height difference as the vertical axis coordinate of the center of the virtual ball.

[0084] The calculation process of the projection distance M between the projection position of any rolling ball 51 and the projection position of the center of the virtual ball is as follows:

[0085] M=|p 1y -p oy |;

[0086] The inner radius R of the ball socket 5 and the radius r of the rolling ball 51 are both fixed structural dimensions and are known data, such as Fig.10 As shown, it can be seen that the sum of the projection distance M, the inner radius R of the ball socket 5 and the radius r of the rolling ball 51 and the height difference H between the center of the virtual ball and the plane where the three rolling balls 51 are located are the three sides of a right triangle. Fig.10 The long right-angled side of the connecting line of the right triangle is M, the short right-angled side is H, and the hypotenuse is R+r. Therefore, the height difference H between the center of the virtual ball and the plane where the three rolling balls 51 are located can be calculated according to the Pythagorean theorem. The calculation process is as follows:

[0087]

[0088] In summary, the coordinates of the center of the virtual ball are (p ox ,p oy ,H).

[0089] In step 104, the coordinate position of the center of the virtual ball is compared with the coordinate position of the theoretical center of the ball socket 5, so as to determine whether the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements.

[0090] Get the horizontal coordinate difference between the horizontal coordinate of the center of the virtual sphere and the horizontal coordinate of the theoretical center; get the vertical coordinate difference between the vertical coordinate of the center of the virtual sphere and the vertical coordinate of the theoretical center; get the vertical coordinate difference between the vertical coordinate of the center of the virtual sphere and the vertical coordinate of the theoretical center.

[0091] In this embodiment, the coordinates of the theoretical center of the ball are (0, 0, H'). Therefore, when the coordinate position of the center of the virtual ball is compared with the coordinate position of the theoretical center of the ball corresponding to the socket 5, the horizontal axis coordinate difference between the horizontal axis coordinate of the center of the virtual ball and the horizontal axis coordinate of the theoretical center of the ball is the horizontal axis coordinate value p of the center of the virtual ball. ox The difference between the vertical axis coordinate of the center of the virtual ball and the vertical axis coordinate of the theoretical center is the vertical axis coordinate value p of the center of the virtual ball. oy The vertical axis coordinate difference between the center of the virtual sphere and the vertical axis coordinate of the theoretical sphere is |H'-H|.

[0092] In summary, the deviation values ​​Δx, Δy and Δz of the center of the virtual ball in each coordinate direction are:

[0093]

[0094]

[0095] When the horizontal axis coordinate difference, the vertical axis coordinate difference and the vertical axis coordinate difference are all less than or equal to the preset difference, the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements.

[0096] When one or more of the horizontal axis coordinate difference, the vertical axis coordinate difference and the vertical axis coordinate difference is greater than the preset difference, the positions of the three rolling balls 51 on the ball socket 5 do not meet the preset requirements.

[0097] In this embodiment, since the coordinates of the center of the virtual ball are calculated using the coordinates of the centers of the three rolling balls 51, when the error between the coordinates of the center of the virtual ball and the position coordinates of the theoretical center of the ball is within an allowable range, it means that the positions of the three rolling balls 51 on the ball socket 5 meet the preset requirements, and after the roller ball is subsequently accommodated in the ball socket 5, the roller ball can roll relatively smoothly; when the error between the coordinates of the center of the virtual ball and the position coordinates of the theoretical center of the ball exceeds the allowable range, it means that the positions of the three rolling balls 51 on the ball socket 5 do not meet the preset requirements, and after the roller ball is subsequently accommodated in the ball socket 5, the roller ball may not be able to roll relatively smoothly.

[0098] The preset difference value is set by those skilled in the art according to actual conditions.

[0099] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for checking the position of a rolling ball in a ball socket, characterized in that: include: A fixing platform (1), a base plate (2), a bracket (3) and an image acquisition module (4), wherein: The fixing platform (1) and the bracket (3) are both arranged on the bottom plate (2), the upper end of the bracket (3) extends to a position above the fixing platform (1), and the image acquisition module (4) is arranged on the upper end of the bracket (3); The fixed platform (1) is used to place a ball socket (5) and to limit and fix the ball socket (5); when the ball socket (5) is arranged on the fixed platform (1), the plane on which the three rolling balls (51) on the ball socket (5) are located is parallel to the horizontal plane; the image acquisition module (4) is used to photograph the ball socket (5) arranged on the fixed platform (1), thereby obtaining the coordinate positions of the three rolling balls (51) on the ball socket (5), obtaining the coordinate position of the center of a virtual ball of the ball socket (5) through the coordinate positions of the three rolling balls (51), and comparing the coordinate position of the center of the virtual ball with the coordinate position of the theoretical center of the ball socket (5), thereby judging whether the positions of the three rolling balls (51) on the ball socket (5) meet preset requirements.

2. The device for checking the position of a rolling ball in a ball socket according to claim 1, characterized in that: The fixing platform (1) comprises a base (11), a limiting groove (12) and at least two threaded holes (13), wherein: The limiting groove (12) is located at the upper end of the base (11); the two threaded holes (13) are both arranged on the upper end surface of the base (11) and are respectively located at two sides of the limiting groove (12); The limiting groove (12) is used to accommodate the ball socket (5); a screw hole platform (54) on one side of the ball socket (5) corresponds to one of the threaded holes (13) and is fixed by screws; and a screw hole platform (54) on the other side of the ball socket (5) corresponds to another threaded hole (13) and is fixed by screws.

3. The device for checking the position of a rolling ball in a ball socket according to claim 2, characterized in that: The bottom surface of the limiting groove (12) is a matching inclined surface (121), and the angle between the matching inclined surface (121) and the horizontal plane is a first preset angle; the angle between the matching inclined surface (52) on the outer surface of the ball socket (5) and the plane where the three rolling balls (51) are located is a second preset angle; the first preset angle and the second preset angle are the same; When the ball socket (5) is located in the limiting groove (12), the matching inclined surface (121) and the matching inclined surface (52) fit each other, thereby ensuring that when the ball socket (5) is fixed in the limiting groove (12), the plane on which the three rolling balls (51) are located is parallel to the horizontal plane.

4. The device for checking the position of a rolling ball in a ball socket according to claim 3, characterized in that: A positioning pin (122) is also provided on the matching inclined surface (121). When the ball socket (5) is located in the limiting groove (12) and the matching inclined surface (121) and the matching inclined surface (52) are in contact with each other, the positioning pin (122) is inserted into the positioning hole (53) on the matching inclined surface (52).

5. The device for checking the position of a rolling ball in a ball socket according to claim 3, characterized in that: The angle between the upper end surface of the base (11) and the horizontal plane is the first preset angle.

6. The device for checking the position of a rolling ball in a ball socket according to any one of claims 1 to 5, characterized in that: The image acquisition module (4) is located directly above the ball socket (5).

7. A method for checking the position of a rolling ball in a ball socket, used for being applied to the device for checking the position of a rolling ball in a ball socket as claimed in any one of claims 1 to 6, characterized in that: include: The ball socket (5) is fixed so that the plane where the three rolling balls (51) on the ball socket (5) are located is parallel to the horizontal plane, and the ball socket (5) is photographed directly above the ball socket (5) to obtain a photo of the ball socket; Obtaining the coordinate positions of three rolling balls (51) respectively according to the ball and socket photographs; Obtaining the coordinate position of the center of the virtual ball of the ball socket (5) through the coordinate positions of the three rolling balls (51); The coordinate position of the center of the virtual ball is compared with the coordinate position of the theoretical center of the ball corresponding to the ball socket (5), so as to determine whether the positions of the three rolling balls (51) on the ball socket (5) meet the preset requirements.

8. The method for checking the position of a rolling ball in a ball socket according to claim 7, characterized in that: The step of obtaining the coordinate position of the center of the virtual ball of the ball socket (5) through the coordinate positions of the three rolling balls (51) specifically includes: The average value of the horizontal axis coordinates of the centers of the three rolling balls (51) is used as the horizontal axis coordinate of the center of the virtual ball, and the average value of the vertical axis coordinates of the centers of the three rolling balls (51) is used as the vertical axis coordinate of the center of the virtual ball; Obtaining the projection position of any rolling ball (51) on the horizontal plane, and the projection position of the center of the virtual ball on the horizontal plane; Obtaining a projection distance between the projection position of any rolling ball (51) and the projection position of the center of the virtual ball; The height difference between the center of the virtual ball and the plane where the three rolling balls (51) are located is obtained according to the projection distance, the inner radius of the ball socket (5) and the radius of the rolling ball (51), and the height difference is used as the vertical axis coordinate of the center of the virtual ball.

9. The method for checking the position of a rolling ball in a ball socket according to claim 8, characterized in that: The step of comparing the coordinate position of the center of the virtual ball with the coordinate position of the theoretical center of the ball corresponding to the ball socket (5) to determine whether the positions of the three rolling balls (51) on the ball socket (5) meet preset requirements specifically includes: Obtain the horizontal axis coordinate difference between the horizontal axis coordinate of the center of the virtual sphere and the horizontal axis coordinate of the center of the theoretical sphere; Obtain the difference between the longitudinal coordinate of the center of the virtual sphere and the longitudinal coordinate of the center of the theoretical sphere; Obtain the vertical axis coordinate difference between the vertical axis coordinate of the center of the virtual sphere and the vertical axis coordinate of the center of the theoretical sphere; When the horizontal axis coordinate difference, the vertical axis coordinate difference and the vertical axis coordinate difference are all less than or equal to the preset difference, the positions of the three rolling balls (51) on the ball socket (5) meet the preset requirements; When one or more of the horizontal axis coordinate difference, the vertical axis coordinate difference and the vertical axis coordinate difference is greater than the preset difference, the positions of the three rolling balls (51) on the ball socket (5) do not meet the preset requirements.

10. The method for checking the position of a rolling ball in a ball socket according to claim 6, characterized in that: The step of obtaining the coordinate positions of the three rolling balls (51) respectively according to the ball and socket photographs specifically includes: Obtaining pixel positions of the centers of the three rolling balls (51) in the ball-and-socket photograph, and respectively obtaining coordinate positions of the centers of the three rolling balls (51) in the industrial camera coordinate system; The industrial camera coordinate system is transformed into a special tooling coordinate system to obtain the coordinate positions of the centers of the three rolling balls (51) in the special tooling coordinate system.

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