Self-centering tip measuring radius detection device and detection method

Abstract

The invention discloses a self-centering tip measuring radius detection device and method, and belongs to the technical field of detection tools.The device comprises a base and a core rod, a center hole is formed in the center of the base, the core rod comprises a first rod body and a second rod body, the first rod body is cylindrical, the diameter of the first rod body is D1, the first rod body is in clearance fit with the center hole, and the second rod body is in clearance fit with the center hole; the second section of rod body is a trapezoidal cylinder, the maximum diameter of the second section of rod body is smaller than D1, a first measuring rod and a second measuring rod are arranged on the base, a first through hole is formed in the workpiece, the inner diameter of the first through hole is D2, the first measuring rod is located at the upper limit position of the tooth-shaped part measuring tip radius of the workpiece, and the second measuring rod is located at the lower limit position of the tooth-shaped part measuring tip radius of the workpiece. The upper limit and the lower limit of the workpiece are judged to have uniqueness; and the first section of rod body moves up and down in the central hole to play a guiding role and self-center the workpiece to be detected, so that the problem that the workpiece is difficult to center due to large tolerance of the through hole is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of detection tooling, and in particular relates to a self-centering measuring tip radius detection device and a detection method. Background Art

[0002] Before leaving the factory, workpieces with partial tooth profiles need to be inspected for the tip radius of the tooth profile to ensure that the tolerance is within the qualified range and that the tooth position of the workpiece is qualified. This workpiece has a circular through hole, which is concentric with the root circle and the top circle of the tooth profile of the workpiece. The tip radius refers to the use of a measuring rod (the diameter of the measuring rod is set according to the designed tooth module. The selection of the measuring rod diameter (d) is mainly related to the module (m), pressure angle (α) and number of teeth (z) of the gear. The goal is to make the contact point between the measuring rod and the tooth profile near the pitch circle of the gear to improve the measurement accuracy) placed in the tooth groove of the tooth profile and close to the tooth surfaces on both sides. At this time, the distance from the center of the circular through hole on the workpiece to the outer end of the measuring rod is the tip radius. The existing method for measuring the tip radius of the tooth profile of the workpiece is as follows: Figure 1 As shown, a push rod (a 100mm long tapered rod with a 0.2mm pull-up and pull-down length) is usually used to insert into the circular through hole on the workpiece. The measuring rod is manually placed against the tooth groove of the toothed part, and the measuring rod is close to the tooth surfaces on both sides between the teeth. Hold the push rod and the measuring rod with one hand, and use a vernier caliper with the other hand to measure the size A. B is the radius of the circular through hole of the workpiece, and A minus B is the measuring tip radius (the complete toothed workpiece is generally tested for the outer distance of the measuring rod between the teeth on both sides - that is, the "span-rod distance" or "measuring tip diameter" or "span-tip diameter". Due to the asymmetry of the teeth of the partially toothed workpiece, only 1 / 2 of the measuring tip diameter (span-rod distance or span-tip diameter) can be tested, so it is named "measuring tip radius" or "span-tip radius"). This manual measurement method manually fixes the measuring rod, which is easy to slide. The measuring rod is easy to turn inward or outward when measuring with a vernier caliper, and it is difficult to measure the maximum distance between the outer rods on both sides. In the actual measurement process, it is found that the error is as large as 0.05 to 0.1 mm. The measurement is extremely inaccurate and has no guiding significance for adjustments in production. At the same time, out-of-tolerance products may be mistakenly judged as qualified, and qualified products may be mistakenly judged as unqualified and scrapped. Summary of the Invention

[0003] In view of the above problems existing in the prior art, the technical problem to be solved by the present invention is to provide a self-centering measuring tip radius detection device and detection method for accurately detecting the measuring tip radius of a partially toothed workpiece.

[0004] Technical solution: In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0005] A self-centering gauge pin radius detection device, comprising a base and a core rod, a center hole corresponding to the core rod is arranged at the center position of the base, the core rod comprises a first rod body and a second rod body, the first rod body is cylindrical and has a diameter D1, the first rod body is in clearance fit with the center hole, the second rod body is a trapezoidal cylinder, the maximum diameter of the second rod body is smaller than D1, the base is provided with a first measuring rod and a second measuring rod for detecting the gauge pin radius of the tooth-shaped part of the workpiece, the workpiece is provided with a first through hole with an inner diameter D2, the minimum diameter of the second rod body is smaller than D2, and the maximum diameter of the second rod body is greater than D2, the first measuring rod is located at the upper limit position of the gauge pin radius of the tooth-shaped part of the workpiece, and the second measuring rod is located at the lower limit position of the gauge pin radius of the tooth-shaped part of the workpiece.

[0006] Preferably, the first measuring rod (3) and the second measuring rod are both cylindrical and have a diameter d, 1mm≤d≤15mm, the height of the first measuring rod 3 and the second measuring rod 4 beyond the base is h, and the height of the workpiece is h4, h>h4.

[0007] Preferably, the workpiece is provided with more than one tooth-shaped part, and the first measuring rod and the second measuring rod are respectively provided with more than one.

[0008] Preferably, the upper end surface of the base is a plane corresponding to the workpiece.

[0009] Preferably, the second rod body comprises more than two outer diameter sections, and the diameters of the more than two outer diameter sections gradually increase from top to bottom.

[0010] Preferably, the inner diameter of the center hole is D3, and 0.002mm≤D3-D1≤0.008mm.

[0011] Preferably, the first measuring rod and the second measuring rod both comprise a guide section and a working section, the diameter of the guide section is d1, and the diameter of the working section is d2, d2>d1.

[0012] The application also provides a self-centering gauge pin radius detection method, which uses the self-centering gauge pin radius detection device described above and comprises the following steps:

[0013] Step S1, the core rod is penetrated through the center hole of the base from bottom to top until the first rod body is located in the center hole;

[0014] Step S2, the first through hole of the workpiece to be detected is sleeved on the second rod body of the core rod from top to bottom, and the workpiece slides up and down on the second rod body to stop at a position corresponding to the inner diameter of the first through hole;

[0015] Step S3, the workpiece is rotated so that the tooth-shaped part is located above the first measuring rod;

[0016] Step S4, the core rod is lowered to drive the workpiece to move downwards, if the first measuring rod does not block the workpiece, the tooth profile radius of the workpiece is less than the upper limit of the specification, and the workpiece upper limit is qualified; if the first measuring rod blocks the workpiece, the tooth profile radius of the workpiece is greater than the upper limit of the specification, and the workpiece upper limit is unqualified;

[0017] Step S5, after the upper limit measurement of the tooth profile radius of the workpiece is completed, the core rod is moved upwards, and then the workpiece is rotated so that the tooth profile is located above the second measuring rod;

[0018] Step S6, the core rod is lowered to drive the workpiece to move downwards, if the second measuring rod does not block the workpiece, the tooth profile radius of the workpiece is less than the lower limit of the specification, and the workpiece lower limit is unqualified; if the second measuring rod blocks the workpiece, the tooth profile radius of the workpiece is greater than the lower limit of the specification, and the workpiece lower limit is qualified;

[0019] Preferably, in the steps S4 and S6, when the core rod is lowered, the first rod body is always located in the center hole.

[0020] Beneficial effects: Compared with the prior art, the present application has the following advantages:

[0021] 1. The self-centering radius detection device of the present application can quickly and simply determine whether the workpiece falls into the measuring rod after the workpiece through hole cooperates with the core rod, and the upper limit and lower limit of the workpiece are unique, fast and accurate, and the correct detection result can guide the workpiece production adjustment.

[0022] 2. By setting the base and the core rod, the center hole is arranged on the base, the lower half of the core rod is the first rod body, the first rod body corresponds to the center hole and the distance is within 0.008mm, and when the workpiece radius is detected, the first rod body moves up and down in the center hole to guide and center the workpiece to be detected, the center of the workpiece through hole is highly concentric with the center of the core rod, and the problem of large workpiece through hole tolerance and difficult centering is solved.

[0023] 3. When measuring the upper limit of the workpiece, the upper limit qualified workpiece can fall to the upper surface of the base with the movement of the core rod, the judgment is accurate, and the upper limit qualified product will not be misjudged as out of tolerance, and the upper limit unqualified workpiece cannot fall, so the upper limit out of tolerance product will not be misjudged as qualified. When measuring the lower limit of the workpiece, the lower limit qualified workpiece can be blocked by the measuring rod with the movement of the core rod, and no matter how the workpiece moves, it will not fall, the judgment is accurate, and the lower limit qualified product will not be misjudged as out of tolerance, and the lower limit unqualified workpiece falls, so the lower limit out of tolerance product will not be misjudged as qualified, which has guiding significance for the production of the workpiece. If the upper limit is unqualified, the upper limit of the workpiece is adjusted, and if the lower limit is unqualified, the lower limit of the workpiece is adjusted. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1is the present artificial measurement method in the push bar and the measurement bar using state diagram;

[0025] Figure 2 is the workpiece structure schematic diagram in the embodiment of the application;

[0026] Figure 3 is the measuring tip radius standard schematic diagram of the workpiece in the embodiment of the application;

[0027] Figure 4 is the cross section structure schematic diagram of the device in the embodiment of the application;

[0028] Figure 5 is the cross section structure schematic diagram of the base in the embodiment of the application;

[0029] Figure 6 is the cross section structure schematic diagram of the mandrel in the embodiment of the application;

[0030] Figure 7 is the first measurement bar structure schematic diagram in the embodiment of the application;

[0031] Figure 8 is the overhead structure schematic diagram of the base in the embodiment of the application;

[0032] Figure 9 is the first tooth shape part upper limit state schematic diagram of the device detecting the workpiece in the embodiment of the application;

[0033] Figure 10 is the first tooth shape part lower limit state schematic diagram of the device detecting the workpiece in the embodiment of the application;

[0034] Figure 11 is the second tooth shape part upper limit state schematic diagram of the device detecting the workpiece in the embodiment of the application;

[0035] Figure 12 is the second tooth shape part lower limit state schematic diagram of the device detecting the workpiece in the embodiment of the application. DETAILED DESCRIPTION

[0036] The application will be further illustrated below in conjunction with specific embodiments, which are implemented on the premise of the technical scheme of the application, and it should be understood that these embodiments are only used for illustrating the application and not for limiting the scope of the application.

[0037] As Figure 2 and Figure 3As shown, the workpiece 9 of the embodiment is a main tooth plate for angle adjustment of an automobile seat, and similar partial tooth workpieces are widely used in angle adjustment of partial circumferential direction. The workpiece 9 has a first through hole 901, and the workpiece 9 is provided with two tooth-shaped portions, i.e., a first tooth-shaped portion 91 and a second tooth-shaped portion 92. The first tooth-shaped portion 91 includes three first teeth, and the second tooth-shaped portion 92 includes four second teeth. The dedendum circle and the addendum circle of the first tooth-shaped portion 91 are concentric with the first through hole 901, and the dedendum circle and the addendum circle of the second tooth-shaped portion 92 are concentric with the first through hole 901. The inner diameter of the first through hole 901 is D2, and in the embodiment, D2 = 16.12 ± 0.04 mm. The standard addendum radius of the first tooth-shaped portion 91 is 42.07( +0.04 / -0.12 ) mm, the upper limit is 42.11 mm, and the lower limit is 41.95 mm. The standard addendum radius of the second tooth-shaped portion 92 is 32.08( +0.04 / -0.12 ) mm, the upper limit is 32.12 mm, and the lower limit is 31.96 mm.

[0038] As shown in Figure 4 , Figure 5 , Figure 6 and Figure 7 , the self-centering addendum radius detection device of the embodiment includes a base 1 and a core rod 2. The base 1 is in the shape of a whole ring, and the upper end surface of the base 1 is a plane corresponding to the workpiece. The lower end surface of the base 1 has a downwardly protruding step in the middle (to increase the guiding length of the center hole), and the center position of the base 1 is provided with a center hole 11 penetrating upward and downward. The center hole 11 is a circular hole, and the inner diameter of the center hole 11 is D3, D3 = 16.15( +0.006 / +0.004 ) mm.

[0039] As shown in Figure 4 , Figure 5 , Figure 6 and Figure 8As shown, the mandrel 2 corresponds to the center hole 11 of the base 1, the mandrel 2 comprises a first section of rod body 21 and a second section of rod body 22, the first section of rod body 21 and the second section of rod body 22 are integrally connected, the first section of rod body 21 is located below the second section of rod body 22, the first section of rod body 21 is cylindrical and the diameter D1 is 16.15±0.002mm, the upper limit of D1 is 16.15+0.002mm, the lower limit of D1 is 16.15-0.002mm, 0.002mm≤D3-D1≤0.008mm, that is, the fitting clearance is 0.002-0.008mm (if the center hole 11 and the first section of rod body 21 are both in the middle value, the ideal fitting clearance is 0.005mm, which ensures that the center of the mandrel 2 is basically coincided with the center of the center hole 11 of the base 1), the first section of rod body 21 is in clearance fit with the center hole 11, so that the first section of rod body 21 can be concentric with the center hole 11 (the center point deviation is between 0.001-0.004mm) when it is in the center hole 11, which plays a self-centering role. The second section of rod body 22 is a trapezoidal cylinder, in this embodiment, the second section of rod body 22 is designed with four outer diameter sections arranged from top to bottom in reference to the actual distribution of the diameter D2 of the first through hole 901 of the workpiece 9 (the actual measurement of the workpiece 9 is 16.11-16.15), which are the first outer diameter section 221, the second outer diameter section 222, the third outer diameter section 223 and the fourth outer diameter section 224, the diameters of the four outer diameter sections gradually increase from top to bottom, the diameter of the first outer diameter section 221 is 16.11±0.002mm, the diameter of the second outer diameter section 222 is 16.12±0.002mm, the diameter of the third outer diameter section 223 is 16.13±0.002mm, and the diameter of the fourth outer diameter section 224 is 16.14±0.002mm. Adding the diameter D1 of the first section of rod body 21 which is 16.15±0.002mm, there are five trapezoidal outer diameter sections in total, the upper end of the second section of rod body 22 has a diameter of 16mm, which is the smallest diameter of the second section of rod body 22, the smallest diameter of the second section of rod body 22 is smaller than D2, which facilitates the first through hole 901 of the workpiece 9 to be sleeved, the diameter D1 of the first section of rod body 21 is 16.15±0.002mm, which is the maximum value of the actual distribution of the diameter D2 of the first through hole 901 of the workpiece 9 (the workpiece 9 with the maximum through hole diameter is tightly fitted with the first section of rod body 21).

[0040] As Figure 4 , Figure 5 , Figure 6 and Figure 8As shown, the base 1 is provided with a first measuring rod 3 and a second measuring rod 4, which are used to detect the tip radius of the workpiece 9. Since the tooth-shaped part is provided with two, the first measuring rod 3 and the second measuring rod 4 are also provided with two, two first measuring rods 3 are respectively used to detect the upper limit of the tip radius of the first tooth-shaped part 91 and the second tooth-shaped part 92, and two second measuring rods 4 are respectively used to detect the lower limit of the tip radius of the first tooth-shaped part 91 and the second tooth-shaped part 92; the first measuring rod 3 is located at the upper limit position of the tip radius of the tooth-shaped part of the workpiece 9 (the upper limit position is a virtual circular ring on the base 1, and the first measuring rod 3 can be located at any position in the virtual circular ring), and the second measuring rod 4 is located at the lower limit position of the tip radius of the tooth-shaped part of the workpiece 9 (the lower limit position is another virtual circular ring on the base 1, and the second measuring rod 4 can be located at any position in the virtual circular ring). Figure 5The first upper limit and the first lower limit correspond to the first tooth-shaped portion 91. Since the upper limit of the tip radius of the first tooth-shaped portion 91 is 42.07+0.04 mm=42.11 mm, the radius at the first upper limit (the distance from the outermost side of the first measuring rod 3 to the center of the center hole 11 at this point is the upper limit of the tip radius of the first tooth-shaped portion 91, that is, the center distance from the center of the first measuring rod 3 to the center of the center hole 11 at this point plus the radius of the first measuring rod 3 is equal to the upper limit of the tip radius of the first tooth-shaped portion 91) is 42.11 mm (the general design and manufacturing tolerance of the gauge is 0.002-0.004, and the one-way tolerance or two-way tolerance is determined according to the actual situation, and the upper limit position of the design and manufacturing tolerance of this case is designed as-0.003 one-way tolerance, that is, 42.11(0 / -0.003) mm), and the lower limit of the tip radius of the first tooth-shaped portion 91 is 42.07-0.12 mm, and the radius at the first lower limit (the distance from the outermost side of the second measuring rod 4 to the center of the center hole 11 at this point is the lower limit of the tip radius of the first tooth-shaped portion 91, that is, the center distance from the center of the second measuring rod 4 to the center of the center hole 11 at this point plus the radius of the first measuring rod 3 is equal to the lower limit of the tip radius of the first tooth-shaped portion 91) is 41.95 mm (the design and manufacturing size and tolerance of the lower limit position of this embodiment is 41.95(+0.003 / 0) mm). The second upper limit and the second lower limit correspond to the second tooth-shaped portion 92. Since the upper limit of the tip radius of the second tooth-shaped portion 92 is 32.08+0.04 mm, the radius at the second upper limit (the distance from the outermost side of the first measuring rod 3 to the center of the center hole 11 at this point is the upper limit of the tip radius of the second tooth-shaped portion 92, that is, the center distance from the center of the first measuring rod 3 to the center of the center hole 11 at this point plus the radius of the first measuring rod 3 is equal to the upper limit of the tip radius of the second tooth-shaped portion 92) is 32.12 mm (the design and manufacturing size and tolerance of this embodiment is 32.12(0 / -0.003) mm), and the lower limit of the tip radius of the second tooth-shaped portion 92 is 32.08-0.12 mm, and the radius at the second lower limit (the distance from the outermost side of the second measuring rod 4 to the center of the center hole 11 at this point is the lower limit of the tip radius of the second tooth-shaped portion 92, that is, the center distance from the center of the second measuring rod 4 to the center of the center hole 11 at this point plus the radius of the second measuring rod 4 is equal to the lower limit of the tip radius of the second tooth-shaped portion 92) is 31.96 mm (the design and manufacturing size and tolerance of the lower limit position of this embodiment is 31.96(+0.003 / 0) mm).

[0041] As Figure 5 And Figure 7As shown, the first measuring rod 3 and the second measuring rod 4 are both cylindrical and have a diameter d, 1mm≤d≤15mm, the height of the first measuring rod 3 and the second measuring rod 4 beyond the base 1 is h, the height of the workpiece 9 is h4, h>h4, the height h4 of the workpiece 9 in the embodiment is 2.66-2.91mm, and the height h of the measuring rod beyond the base in the embodiment is designed as h=10mm. The first measuring rod 3 and the second measuring rod 4 both include a guiding section 31, a working section 32 and a clamping section 33, the height of the guiding section 31 is h1, the height of the working section 32 is h2, and the height of the clamping section 33 is h3, the guiding section 31 and the working section 32 are beyond the upper end surface of the base 1, h=h1+h2, the base 1 is provided with a slot hole corresponding to the clamping section 33, and the clamping section 33 is connected with the base 1 in interference. h2>h4, the height of the working section 32 is also greater than the height of the workpiece 9, h1=h2=5mm in the embodiment, h3=15mm, the diameter of the guiding section 31 is d1, the diameter of the working section 32 is d2, d2=d, and d2≥d1, d2=d=5mm in the embodiment, d1=4.9mm, and the diameter of the clamping section 33 is equal to the diameter of the working section 32. The guiding section 31 is provided to facilitate the guiding of the tooth-shaped part of the workpiece 9 during detection.

[0042] The embodiment also discloses a self-centering measuring rod radius detection method, which uses the self-centering measuring rod radius detection device and includes the following steps.

[0043] Step 1, the core rod 2 is penetrated through the center hole 11 of the base 1 from bottom to top until the first section rod body 21 is located in the center hole 11;

[0044] Step 2, the first through hole 901 of the workpiece 9 to be detected is sleeved on the second section rod body 22 of the core rod 2 from top to bottom, the workpiece 9 is slid down on the second section rod body 22 to stop at a position corresponding to the inner diameter of the first through hole 901 (the workpiece 9 and the second section rod body 22 are in close fit), and the inner diameter D2 of the first through hole 901 of the workpiece 9 in the embodiment is 16.14mm, so that the workpiece 9 stops when sliding down to the fourth outer diameter section 224;

[0045] Step 3, the first tooth-shaped part 91 is located above the first measuring rod 3 by rotating the workpiece 9;

[0046] Step 4, the core rod 2 is lowered to drive the workpiece 9 to be lowered synchronously, and the first section rod body 21 is always located in the center hole 11 when the core rod 2 is lowered, thereby playing a self-centering role, such as Figure 9If the first measuring rod 3 at the first upper limit does not block the workpiece 9 (the first tooth profile 91 of the workpiece 9 falls inside the first measuring rod 3 at the first upper limit), the first tooth profile 91 of the workpiece 9 has a first tooth profile radius smaller than the upper limit of the specification (if the first tooth profile 91 of the workpiece 9 falls inside the first measuring rod 3 at the first upper limit, the first tooth profile 91 of the workpiece 9 has a first tooth profile radius at the upper limit of the specification), and the first tooth profile 91 of the workpiece 9 is qualified at the upper limit; if the first measuring rod 3 at the first upper limit blocks the workpiece 9 (the first tooth profile 91 of the workpiece 9 cannot fall inside the first measuring rod 3 at the first upper limit), the first tooth profile 91 of the workpiece 9 has a first tooth profile radius greater than the upper limit of the specification, and the first tooth profile 91 of the workpiece 9 is unqualified at the upper limit.

[0047] Step 5, after the upper limit detection of the first tooth profile radius of the workpiece 9 is completed, the mandrel 2 is moved upward, and then the workpiece 9 is rotated so that the first tooth profile 91 is located above the second measuring rod 4 at the first lower limit;

[0048] Step 6, the mandrel 2 is lowered to drive the workpiece 9 to be lowered synchronously, and when the mandrel 2 is lowered, the first rod body 21 is always located in the center hole 11 to serve as a self-centering function, as shown in Figure 10 If the second measuring rod 4 at the first lower limit does not block the workpiece 9 (the first tooth profile 91 of the workpiece 9 falls inside the second measuring rod 4 at the first lower limit), the first tooth profile 91 of the workpiece 9 has a first tooth profile radius smaller than the lower limit of the specification (if the first tooth profile 91 of the workpiece 9 falls inside the second measuring rod 4 at the first lower limit, the first tooth profile 91 of the workpiece 9 has a first tooth profile radius at the lower limit of the specification), and the first tooth profile 91 of the workpiece 9 is unqualified at the lower limit; if the second measuring rod 4 at the first lower limit blocks the workpiece 9 (the first tooth profile 91 of the workpiece 9 cannot fall inside the second measuring rod 4 at the first lower limit), the first tooth profile 91 of the workpiece 9 has a first tooth profile radius greater than the lower limit of the specification, and the first tooth profile 91 of the workpiece 9 is qualified at the lower limit;

[0049] Step 7, after the detection of the first tooth profile 91 is completed, the mandrel 2 is moved upward, and then the workpiece 9 is rotated so that the second tooth profile 92 is located above the first measuring rod 3 at the second upper limit;

[0050] Step 8, the mandrel 2 is lowered to drive the workpiece 9 to be lowered synchronously, and when the mandrel 2 is lowered, the first rod body 21 is always located in the center hole 11 to serve as a self-centering function, as shown in Figure 11If the first measuring rod 3 at the second upper limit does not block the workpiece 9 (the second tooth profile 92 of the workpiece 9 falls inside the first measuring rod 3 at the second upper limit), the second tooth profile 92 of the workpiece 9 has a tip radius less than the upper limit of the specification (the second tooth profile 92 of the workpiece 9 falls inside the first measuring rod 3 at the second upper limit), and the second tooth profile 92 of the workpiece 9 is qualified at the upper limit; if the first measuring rod 3 at the second upper limit blocks the workpiece 9 (the second tooth profile 92 of the workpiece 9 cannot fall inside the first measuring rod 3 at the second upper limit), the second tooth profile 92 of the workpiece 9 has a tip radius greater than the upper limit of the specification, and the second tooth profile 92 of the workpiece 9 is unqualified at the upper limit.

[0051] Step 9, after the upper limit measurement of the tip radius of the second tooth profile of the workpiece 9 is completed, the mandrel 2 is moved upward, and then the workpiece 9 is rotated so that the second tooth profile is above the second measuring rod 4 at the second lower limit;

[0052] Step 10, the mandrel 2 is lowered to synchronously lower the workpiece 9, and when the mandrel 2 is lowered, the first rod body 21 is always located inside the center hole 11, thereby playing a self-centering role, as shown in Figure 12 If the second measuring rod 4 at the second lower limit does not block the workpiece 9 (the second tooth profile 92 of the workpiece 9 falls inside the second measuring rod 4 at the second lower limit), the second tooth profile 92 of the workpiece 9 has a tip radius less than the lower limit of the specification (the second tooth profile 9 of the workpiece 9 falls inside the second measuring rod 4 at the second lower limit), and the second tooth profile 92 of the workpiece 9 is unqualified at the lower limit; if the second measuring rod 4 at the second lower limit blocks the workpiece 9 (the second tooth profile 92 of the workpiece 9 cannot fall inside the second measuring rod 4 at the second lower limit), the second tooth profile 92 of the workpiece 9 has a tip radius greater than the lower limit of the specification, and the second tooth profile 92 of the workpiece 9 is qualified at the lower limit.

[0053] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A self-centering measuring tip radius detection device, characterized in that: The invention comprises a base (1) and a core rod (2), wherein a center hole (11) corresponding to the core rod (2) is provided at the center position of the base (1), and the core rod (2) comprises a first section rod body (21) and a second section rod body (22), wherein the first section rod body (21) is cylindrical and has a diameter of D1, and the first section rod body (21) is loosely matched with the center hole (11), and the second section rod body (22) is a trapezoidal cylinder, and the maximum diameter of the second section rod body (22) is smaller than D1, and the base (1) is provided with a A first measuring rod (3) and a second measuring rod (4) for measuring the tip radius of a toothed portion of a workpiece (9); the workpiece (9) is provided with a first through hole (901); the inner diameter of the first through hole (901) is D2; the diameter of the second section of the rod (22) is smaller than D2 at its smallest point, and larger than D2 at its largest point; the first measuring rod (3) is located at the upper limit of the tip radius of the toothed portion of the workpiece (9); and the second measuring rod (4) is located at the lower limit of the tip radius of the toothed portion of the workpiece (9).

2. The self-centering tip radius detection device according to claim 1, characterized in that: The first measuring rod (3) and the second measuring rod (4) are both cylindrical and have a diameter d, 1mm≤d≤15mm. The height of the first measuring rod 3 and the second measuring rod 4 beyond the base (1) is h, and the height of the workpiece (9) is h4, h>h4.

3. The self-centering tip radius detection device according to claim 2, characterized in that: The workpiece (9) is provided with more than one tooth-shaped portion, and the first measuring rod (3) and the second measuring rod (4) are respectively provided with more than one tooth-shaped portion.

4. The self-centering tip radius detection device according to claim 1, characterized in that: The upper end surface of the base (1) is a plane corresponding to the workpiece.

5. The self-centering tip radius detection device according to claim 1, characterized in that: The second rod body (22) comprises more than two outer diameter sections, and the diameters of the two or more outer diameter sections gradually increase from top to bottom.

6. The self-centering tip radius detection device according to claim 1, characterized in that: The inner diameter of the central hole (11) is D3, and the value of 0.002 mm≤D3-D1≤0.008 mm.

7. The self-centering tip radius detection device according to claim 2, characterized in that: The first measuring rod (3) and the second measuring rod (4) both comprise a guide section (31) and a working section (32); the guide section (31) has a diameter of d1, the working section (32) has a diameter of d2, and d2>d1.

8. A method for detecting a self-centering measuring tip radius, using the self-centering measuring tip radius detection device according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step S1, passing the core rod (2) through the center hole (11) of the base (1) from bottom to top until the first section of the rod (21) is located in the center hole (11); Step S2: The first through hole (901) of the workpiece (9) to be inspected is placed on the second rod section (22) of the core rod (2) from top to bottom, and the workpiece (9) slides up and down on the second rod section (22) to a position corresponding to the inner diameter of the first through hole (901) and stops; Step S3, rotating the workpiece (9) so that the toothed portion is located above the first measuring rod (3); Step S4, the core rod (2) is moved downward to drive the workpiece (9) to move downward. If the first measuring rod (3) does not block the workpiece (9), the measuring tip radius of the tooth-shaped portion of the workpiece (9) is less than the upper limit of the specification, and the workpiece (9) is qualified at the upper limit. If the first measuring rod (3) blocks the workpiece (9), the measuring tip radius of the tooth-shaped portion of the workpiece (9) is greater than the upper limit of the specification, and the workpiece (9) is unqualified at the upper limit. Step S5: After the upper limit of the tip radius of the toothed portion of the workpiece (9) is measured, the core rod (2) is moved upward, and then the workpiece (9) is rotated so that the toothed portion is located above the second measuring rod (4); Step S6, the core rod (2) is moved downward to drive the workpiece (9) to move downward. If the second measuring rod (4) does not block the workpiece (9), the measuring tip radius of the tooth-shaped portion of the workpiece (9) is less than the lower limit of the specification, and the lower limit of the workpiece (9) is unqualified; if the second measuring rod (4) blocks the workpiece (9), the measuring tip radius of the tooth-shaped portion of the workpiece (9) is greater than the lower limit of the specification, and the lower limit of the workpiece (9) is qualified.

9. The self-centering tip radius detection method according to claim 8, characterized in that: When the core rod (2) moves downward in steps S4 and S6, the first section of the rod (21) is always located in the center hole (11).

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