A device for measuring the margin of safety holes of threaded parts

Abstract

The present invention relates to a device for measuring the margin of a safety hole of a threaded part, comprising a measuring table, the measuring table comprising a case, a measuring head and a display panel, the measuring head being able to elastically extend and retract relative to the case to drive a pointer in the display panel to swing to a corresponding angle, a measuring positioning piece being fixed on the case, the measuring device also comprising a reference rod for inserting into the safety hole of the threaded part to be measured, the reference rod being used to coaxially cooperate with the safety hole and having both ends extending out of the safety hole, the measuring positioning piece having a positioning reference surface for contacting with both ends of the reference rod extending out of the safety hole, a measuring contact piece being guided and moved along the direction of extension and retraction of the measuring head on the measuring positioning piece, one end of the measuring contact piece along the direction of extension and retraction of the measuring head having a measuring plane for contacting with the edge of the threaded part to be measured, and the other end having a measuring head top press-fit surface for press-fitting with the measuring head top. The measuring device in the present invention can realize the measurement of the margin of the safety hole of the threaded part, and the measurement is convenient and fast, thereby improving efficiency.

Description

Technical Field

[0001] The invention relates to a measuring device, in particular to a device for measuring the margin of a safety hole of a threaded part. Background Art

[0002] In aerospace and military threaded fastener products, threaded fasteners with safety holes on the head are usually used. For example, the invention patent application with the authorization announcement number CN111677744B discloses a double safety connection structure, a turboprop aircraft engine and a double safety fixing method, which involves a threaded fastener with a safety hole. The threaded fastener has a hexagonal head nut, and the safety hole is opened on the hexagonal head nut in a direction perpendicular to the axis of the threaded fastener. As shown below Figure 1 As shown, the safety hole 02 is opened at a position close to one of the edges of the hexagonal nut 01 , multiple safety holes 02 are opened on the same nut 01 , and the axis of one safety hole 02 is perpendicular to one pair of side surfaces of the hexagonal nut 01 .

[0003] The actual processed threaded parts have accuracy requirements for the position of the safety hole. Before the product leaves the factory, it is necessary to measure whether the distance between the center axis of the safety hole and the edge of the hexagonal nut meets the requirements. In the field, the distance between the center axis of the safety hole and the edge of the hexagonal nut is called the safety hole margin, that is, Figure 1 The L in.

[0004] In the prior art, there are commonly measuring devices such as groove depth measurement and surface height difference measurement. For example, a circular arc groove and end face groove depth measuring tool disclosed in the utility model patent with authorization announcement number CN213396896U includes a base and a measuring table fixed on the base by a top screw, wherein the measuring table is a common standard part in the field, including a scale display plate, a case, and a measuring head that can be elastically extended and retracted relative to the case. When the measuring head is elastically extended and retracted relative to the case, it will drive the pointer in the scale display plate to swing to a corresponding angle. The bottom surface of the base is provided with a reference surface, and the measuring head extends out of the reference surface. When in use, the outer surface of the workpiece to be measured is positioned and matched with the reference surface, and the measuring head is extended into the end face groove of the workpiece to be measured. The measuring head is pressed against the bottom of the groove of the end face groove. At this time, the measuring head shrinks upward, and at the same time, the pointer in the scale display plate points to the corresponding scale. The degree is the relative depth of the end face groove.

[0005] For another example, the utility model patent with the authorization announcement number CN210952673U discloses a surface height difference measuring device, which includes a dial indicator stand and a dial indicator, and the dial indicator is also a measuring meter. The measuring device can measure the surface height difference in a small space.

[0006] The above two measuring devices use a measuring table to measure the end face groove depth and surface height difference, and can directly read the value. The measurement is convenient and fast, but the above two measuring devices cannot be applied to the measurement of the margin of the safety hole. The conventional method of detecting the margin of the safety hole in the prior art is to use a projector to detect the hole margin. First, a stop rod matching the hole diameter is inserted into the safety hole, and then it is placed under the projector for alignment. The center axis of the safety hole is found by the stop rod, and the distance from the edge to the center axis of the hole is measured. This measurement method is difficult to align, resulting in low measurement efficiency. Summary of the invention

[0007] The purpose of the present invention is to provide a device for measuring the margin of a safety hole of a threaded part, so as to solve the technical problems of difficult alignment and low measuring efficiency in the prior art.

[0008] In order to achieve the above-mentioned purpose, the technical solution of a device for measuring the margin of a threaded part safety hole provided by the present invention is:

[0009] A device for measuring the margin of a safety hole of a threaded part, comprising a measuring gauge, the measuring gauge comprising a gauge case, a measuring head and a display panel, the measuring head being able to elastically extend and retract relative to the gauge case to drive a pointer in the display panel to swing to a corresponding angle, a measuring positioning piece being fixed on the gauge case, the measuring device also comprising a reference rod for inserting into the safety hole of the threaded part to be measured, the reference rod being used to coaxially cooperate with the safety hole and having both ends extending out of the safety hole, the measuring positioning piece having a positioning reference surface for contacting with both ends of the reference rod extending out of the safety hole, a measuring contact piece being assembled on the measuring positioning piece for guiding movement along the extension and retraction direction of the measuring head, the measuring contact piece having a measuring plane at one end along the extension and retraction direction of the measuring head for contacting with the edge of the threaded part to be measured, and a measuring head top press-fit surface at the other end for press-fitting with the measuring head top.

[0010] The beneficial effect is as follows: the present invention utilizes a measuring table, fixes a measuring positioning piece on the table case of the measuring table, sets a positioning reference surface on the measuring positioning piece, and sets a reference rod for being installed in the safety hole of the threaded part to be measured. When measuring the threaded part to be measured, the reference rod is inserted into the safety hole. In the process of the reference rod moving toward the positioning reference surface until it contacts the positioning reference surface, the measuring contact piece presses the measuring head of the measuring table. Correspondingly, the pointer in the display panel swings and points to the corresponding scale. The sum of the value corresponding to the scale and the radius of the safety hole is the size of the safety hole margin. The threaded part safety hole margin measuring device of the present invention does not require a complicated alignment process and is easy to operate. At the same time, the safety hole margin can be measured by intuitively reading the value through the measuring table, and the measurement efficiency is high. At the same time, the measuring positioning piece is fixed on the measuring table in the present invention, which can be carried around to achieve mobile measurement.

[0011] As a further improvement, the measuring positioning member has an axial positioning surface for positioning and matching with the axial end surface of the nut of the threaded part to be measured. The axial positioning surface prevents the threaded part to be measured from coming off from one side.

[0012] As a further improvement, the measuring positioning member includes a measuring sleeve, the measuring head extends into the measuring sleeve, the measuring contact member is guided and moved and assembled in the measuring sleeve, and the end surface of the measuring sleeve away from the display panel constitutes the positioning reference surface. The sleeve-type measuring positioning member can be used as a handle structure for easy handholding. At the same time, the measuring head and the positioning contact member can be accommodated therein, which is convenient for assembly.

[0013] As a further improvement, the measuring positioning member includes a positioning block fixed to the end of the measuring sleeve away from the display panel, and the axial positioning surface is located on the positioning block. The threaded part to be measured is axially stopped by fixing the positioning block on the measuring sleeve, and the structure is simple.

[0014] As a further improvement, the positioning block extends to the mouth of the measuring sleeve and cooperates with the measuring contact piece in the axial direction of the measuring sleeve to prevent the measuring contact piece from falling out.

[0015] As a further improvement, the inner hole of the measuring sleeve includes a large diameter hole section and a small diameter hole section, and the measuring contact piece is a force transmission rod including a large diameter rod section and a small diameter rod section, the small diameter rod section of the force transmission rod is guided and matched with the small diameter hole section of the measuring sleeve, and the large diameter rod section is guided and matched with the large diameter hole section. By setting the inner hole of the measuring sleeve as a stepped hole and the measuring contact piece as a stepped shaft, when the force transmission rod is inserted, the small diameter rod section of the force transmission rod is first inserted into the large diameter hole section for easy insertion, and then the large diameter rod section is guided and matched with the large diameter hole section, and the small diameter rod section is guided and matched with the small diameter hole section, thereby ensuring the stability of the force transmission rod during movement.

[0016] As a further improvement, the case includes a measuring rod, the case includes a measuring rod, the display panel and the measuring head are respectively located at both ends of the measuring rod, the measuring rod is inserted into a measuring sleeve, and a top screw for fixing the measuring rod in the measuring sleeve is inserted into one radial side of the measuring sleeve. The measuring meter is fixed in the measuring sleeve by the detachable fixing method of the top screw, and the position of the measuring head in the measuring sleeve can be adjusted, and the measuring meter and the measuring contact are conveniently replaced.

[0017] As a further improvement, the measuring sleeve is provided with an avoidance groove for avoiding the edge of the threaded part to be measured, and the avoidance groove penetrates the wall of the measuring sleeve in a direction perpendicular to the axial positioning surface. The avoidance groove is provided and penetrates the wall of the measuring sleeve to facilitate observation of the process of the nut moving to the reference rod and the positioning reference surface.

[0018] As a further improvement, the measuring positioning piece is provided with an avoidance groove for avoiding the edge of the threaded part to be measured, so that the nut can press the measuring contact piece to retract into the measuring positioning piece, thereby reducing the external space occupied by the measuring contact piece.

[0019] As a further improvement, the avoidance groove is a V-shaped groove, and the V-shaped groove is adapted to the shape of the hexagonal nut. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a nut in the prior art;

[0021] Figure 2 It is a structural schematic diagram of a first embodiment of a device for measuring the margin of a safety hole of a threaded part in the present invention;

[0022] Figure 3 for Figure 1 A cross-sectional view of the measuring sleeve;

[0023] Figure 4 for Figure 3 Left view of;

[0024] Figure 5 for Figure 1 Schematic diagram of the structure of the middle force transmission rod;

[0025] Figure 6 This is a measurement state diagram of a threaded part safety hole margin measurement device embodiment 1 of the present invention;

[0026] Description of reference numerals:

[0027] 01. Nut; 02. Safety hole; 1. Display panel; 2. Measuring sleeve; 21. Positioning reference surface; 3. Measuring rod; 4. Measuring head; 5. Force transmission rod; 51. Press-fit surface on top of measuring head; 52. Measuring plane; 53. Step surface; 6. Positioning block; 61. Axial positioning surface; 7. Top screw; 8. Avoidance groove; 9. Reference rod; 10. Nut. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the present invention clearer, 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 used to limit the present invention, that is, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0030] It should be noted that relational terms such as "first" and "second" that may appear are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, terms such as "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, elements defined by the sentence "including a...", etc., do not exclude the process or method that includes the elements.

[0031] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" that may appear should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the term "provided with" that may appear should be understood in a broad sense. For example, the object "provided with" may be a part of the body, or may be arranged separately from the body and connected to the body, and the connection may be a detachable connection or an inseparable connection. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] The present invention is further described in detail below in conjunction with embodiments.

[0034] A specific embodiment 1 of a device for measuring the margin of a threaded part safety hole provided by the present invention: The measuring object in this embodiment is a threaded part whose nut 10 is a hexagonal shape. Figures 2 to 6As shown, the measuring device is a portable structure, including a measuring table and a measuring sleeve 2 fixed on the measuring table, wherein the measuring table includes a case, a display panel 1 and a measuring head 4, the case includes a measuring rod 3, the display panel 1 and the measuring head 4 are respectively located at the two ends of the measuring rod 3, the measuring head 4 can elastically extend and retract relative to the measuring rod 3, and the extension and retraction of the measuring head 4 will drive the pointer in the display panel 1 to swing to a corresponding angle. It should be explained here that the specific way of elastic extension and retraction of the measuring head 4 is: an elastic member is installed in the case to apply force to the measuring head 4 so that the measuring head 4 extends out of the case. Since the measuring table is a common dial indicator in the prior art, the dial indicator is a standard measuring instrument and belongs to a known mature technology in the prior art, which will not be described in detail here. In this embodiment, the measuring rod 3 is installed in the inner hole of the measuring sleeve 2, and the measuring rod 3 is fixed in the measuring sleeve 2 by a top screw 7 installed on the radial side of the measuring sleeve 2, thereby realizing the fixing of the measuring sleeve 2 on the measuring rod 3 of the measuring table. In addition, by loosening the top screw 7, the position of the measuring rod 3 can be adjusted along the axial direction of the measuring sleeve 2, or the measuring meter can be replaced.

[0035] A force transmission rod 5 is installed in the measuring sleeve 2 for guiding movement. The force transmission rod 5 includes a large diameter rod section at the top and a small diameter rod section at the bottom. A step surface 53 is formed between the large diameter rod section and the small diameter rod section. The inner hole of the measuring sleeve 2 includes a large diameter hole section at the top and a small diameter hole section at the bottom. When the force transmission rod 5 is installed, the force transmission rod 5 is inserted into the measuring sleeve 2 from the large diameter hole section at the top of the measuring sleeve 2. The small diameter rod section of the force transmission rod 5 is guided to match with the small diameter hole section of the measuring sleeve 2, and the large diameter rod section is guided to match with the small diameter hole section. One end face of the force transmission rod 5 is a measuring head top press fit surface 51 that is pressed with the measuring head 4, and the other end face is a measuring plane 52 that is used to contact the edge of the nut 10 of the threaded part to be measured. In this embodiment, the upper end face of the force transmission rod 5 is the measuring head top press fit surface 51, and the lower end face is the measuring plane 52. The force transmission rod 5 constitutes a measuring contact piece. The end surface of the measuring sleeve 2 which is away from the display panel 1 , ie, the lower end surface, is the positioning reference surface 21 .

[0036] A positioning block 6 is fixed to the lower end of the measuring sleeve 2. The positioning block 6 extends to the mouth of the measuring sleeve 2 in the width direction and cooperates with the force transmission rod 5 in the axial direction to prevent the force transmission rod 5 from coming out of the measuring sleeve 2. In this embodiment, the measuring plane 52 on the force transmission rod 5 is in the same plane as the positioning reference surface 21. The positioning block 6 has an axial positioning surface 61. The axial positioning surface 61 axially positions the axial end face of the nut 10 of the threaded part to be measured from one side of the positioning reference surface 21 to prevent the nut 10 of the threaded part to be measured from coming out from one side. The positioning block 6 and the measuring sleeve 2 form a measuring positioning member. In this embodiment, after the positioning block 6 is fixed to the lower end of the measuring sleeve 2, a part of the positioning block 6 is located below the force transmission rod 5 and contacts the lower end of the force transmission rod 5, so that the measuring plane 52 at the lower end of the force transmission rod 5 is in the same plane as the positioning reference surface 21.

[0037] One end of the measuring sleeve 2 provided with the positioning reference surface 21 is provided with an avoidance groove 8 for avoiding the edges of the threaded part to be measured. The avoidance groove 8 is a V-shaped groove adapted to the shape of the hexagonal nut 10. The length of the V-shaped groove extends in a direction perpendicular to the axial positioning surface 61 and extends from the outer peripheral surface of the measuring sleeve 2 to the position of the positioning block 6. Since the avoidance groove 8 runs through the wall of the measuring sleeve 2, it is convenient to observe the process of the nut 10 pressing the force transmission rod 5 upward until the reference rod 9 cooperates with the positioning reference surface 21. The V-shaped groove limits the nut 10 from both radial sides of the threaded part to be measured, so that the edges of the nut 10 can always contact the measuring plane 52.

[0038] The threaded part safety hole margin measuring device of the present invention also includes a reference rod 9, which is used to penetrate the nut 10 of the threaded part to be measured, and both ends extend out of the safety hole. During measurement, the two end portions of the reference rod 9 extending out of the safety hole contact the positioning reference surface 21 on the measuring sleeve 2.

[0039] When assembling the threaded part safety hole margin measuring device of the present invention, firstly, the force transmission rod 5 is inserted into the measuring sleeve 2 from the upper end thereof. Due to the blocking effect of the positioning block 6 below, the force transmission rod 5 is prevented from being disengaged and inserted into the measuring sleeve 2. At this time, the measuring plane 52 at the lower end of the force transmission rod 5 is in the same plane as the positioning reference plane 21. Then, the measuring sleeve 2 is sleeved upward from the lower end of the measuring head 4 onto the measuring rod 3 of the measuring table. When the measuring head 4 contacts the upper end face of the force transmission rod 5, the top screw 7 is tightened to fix the measuring sleeve 2 and the measuring rod 3. Adjust the adjustment knob above the display panel 1 so that the pointer in the display panel 1 points to the zero scale.

[0040] When the threaded part insurance hole margin measuring device of the present invention is used to measure the threaded part to be measured, Figure 6 As shown, the reference rod 9 is now inserted into the safety hole on the nut 10 of the threaded part to be measured, and then the nut 10 with the reference rod 9 presses the force transmission rod 5 from bottom to top, the force transmission rod 5 moves upward, and presses the measuring head 4 to move upward together, until the two end parts of the reference rod 9 extending out of the safety hole are in contact with the positioning reference surface 21 at the lower end of the measuring sleeve 2. At this time, read the scale value pointed to by the pointer in the display panel 1, and the sum of the scale value and the radius d of the safety hole is the safety hole margin.

[0041] The specific embodiment 2 of the device for measuring the margin of a threaded part safety hole provided by the present invention is different from the embodiment 1 mainly in that the positioning block 6 and the axial positioning surface 61 can be omitted.

[0042] The specific embodiment 3 of the threaded part safety hole margin measuring device provided by the present invention is different from the embodiment 1 mainly in that the measuring positioning piece only includes the measuring sleeve 2, at this time, a part of the lower end of the measuring sleeve 2 is cut off to form a notch, and the axial positioning surface 61 is formed by the side wall of the notch.

[0043] The specific embodiment 4 of the threaded part safety hole margin measuring device provided by the present invention is different from the embodiment 1 mainly in that the lower positioning block 6 may not stop the force transmission rod 5, but relies on the step surface 53 on the force transmission rod 5 and the inner hole of the measuring sleeve 2 to prevent it from falling off.

[0044] The specific embodiment 5 of the threaded part safety hole margin measuring device provided by the present invention differs from the embodiment 1 mainly in that the measuring rod 3 can be fixed in the measuring sleeve 2 in an interference fit manner, or a thread is provided on the outside of the measuring rod 3 and installed in the measuring sleeve 2 by screwing the thread.

[0045] The specific embodiment 6 of the threaded part safety hole margin measuring device provided by the present invention is different from the embodiment 1 mainly in that the avoidance groove 8 may not be provided at the lower end of the measuring sleeve 2, and a support block is fixed on the opposite sides of the lower end of the measuring sleeve 2 respectively, and the positioning reference surface 21 is set on the two support blocks, and a space for the nut 10 to move is formed between the two support blocks.

[0046] The specific embodiment 7 of the device for measuring the margin of the safety hole of a threaded part provided by the present invention is different from the embodiment 1 mainly in that the shape of the avoidance groove 8 can be set according to the structure of the nut 10 of different shapes.

[0047] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments without creative work, or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A device for measuring the margin of a threaded part safety hole, comprising a measuring meter, the measuring meter comprising a case, a measuring head and a display panel, the measuring head being elastically retractable relative to the case to drive a pointer in the display panel to swing to a corresponding angle, characterized in that: A measuring positioning piece is fixed on the watch case, and the measuring device also includes a reference rod for inserting into the safety hole of the threaded part to be measured, the reference rod is used to coaxially cooperate with the safety hole and extend out of the safety hole at both ends, the measuring positioning piece has a positioning reference surface for contacting the two ends of the reference rod extending out of the safety hole, and a measuring contact piece is installed on the measuring positioning piece to guide and move along the telescopic direction of the measuring head. One end of the measuring contact piece along the telescopic direction of the measuring head has a measuring plane for contacting the edge of the threaded part to be measured, and the other end has a measuring head top press-fit surface that is press-fit with the top of the measuring head, and the measuring plane and the positioning reference surface are in the same plane.

2. The threaded part safety hole margin measuring device according to claim 1, characterized in that: The measuring positioning piece has an axial positioning surface for positioning and matching with an axial end surface of a nut of a threaded part to be measured.

3. The threaded part safety hole margin measuring device according to claim 2, characterized in that: The measuring positioning member comprises a measuring sleeve, the measuring head extends into the measuring sleeve, the measuring contact member is guided and movable and assembled in the measuring sleeve, and an end surface of the measuring sleeve away from the display panel constitutes the positioning reference surface.

4. The threaded part safety hole margin measuring device according to claim 3, characterized in that: The measuring positioning member comprises a positioning block fixed on an end of the measuring sleeve away from the display plate, and the axial positioning surface is located on the positioning block.

5. The threaded part safety hole margin measuring device according to claim 4, characterized in that: The positioning block extends to the opening of the measuring sleeve and is engaged with the measuring contact piece in the axial direction of the measuring sleeve.

6. The device for measuring the margin distance of a threaded part safety hole according to any one of claims 3 to 5, characterized in that: The inner hole of the measuring sleeve includes a large diameter hole section and a small diameter hole section, and the measuring contact piece is a force transmission rod including a large diameter rod section and a small diameter rod section. The small diameter rod section of the force transmission rod is guided and matched with the small diameter hole section of the measuring sleeve, and the large diameter rod section is guided and matched with the large diameter hole section.

7. The threaded part safety hole margin measuring device according to any one of claims 3 to 5, characterized in that: The watch case comprises a measuring rod, the display panel and the measuring head are respectively located at two ends of the measuring rod, the measuring rod is inserted into a measuring sleeve, and a top screw for fixing the measuring rod in the measuring sleeve is inserted into one radial side of the measuring sleeve.

8. The device for measuring the margin distance of a threaded part safety hole according to any one of claims 3 to 5, characterized in that: The measuring sleeve is provided with an avoidance groove for avoiding the edge of the threaded part to be measured, and the avoidance groove penetrates the wall of the measuring sleeve in a direction perpendicular to the axial positioning surface.

9. The threaded part safety hole margin measuring device according to any one of claims 1 to 5, characterized in that: The measuring positioning piece is provided with an avoidance groove for avoiding the edge of the threaded part to be measured.

10. The threaded part safety hole margin measuring device according to claim 9, characterized in that: The avoidance groove is a V-shaped groove.

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