Relative angle testing fixture for camshaft
By designing a relative angle detection tool for an annular body, using the module split line and signal wheel detection boss, the problem of low camshaft detection efficiency in the prior art is solved, fast and accurate angle detection is achieved, and the demand for mass production is met.
Patent Information
- Application Number
- CN202422064108.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-23
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-08-23
AI Technical Summary
The existing camshaft detection methods are inefficient and cannot meet the inspection needs of mass production, especially the angle detection of the tail keyway relative to the hexagonal and signal wheels is difficult to accurately complete.
A relative angle detector for an annular body is designed to indirectly judge the angle of the tail keyway and the camshaft split line by detecting the angle of the tail keyway relative to the hexagon, and the angle of the tail keyway and the signal wheel are detected by the signal wheel detection boss correlation.
It realizes rapid and accurate detection of the angle between the keyway at the tail end of the camshaft relative to the hexagon and signal wheel, improves detection efficiency, meets the inspection needs of mass production, and reduces costs.
Smart Images
Figure CN222912615U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of camshaft inspection tools, in particular to a relative angle inspection tool for a camshaft. Background Technique
[0002] As an important component part of an automobile engine, the main function of a camshaft is to control the opening / closing action of a valve. Generally, the existing camshaft is designed with a thread, a hexagonal structure, a support journal structure, a cam structure, a signal wheel structure, and a tail-end keyway structure. Moreover, there are clear requirements for the positional relationship among the hexagon, the keyway, the cam, and the signal wheel.
[0003] Among them, when the camshaft is installed in the engine, a tooling is first used to clamp the tail-end keyway to make it horizontal and unable to rotate. When the position of the keyway is fixed, at this time, the hexagon, the cam angle, and the signal wheel angle are also fixed. After the camshaft is fixed, a VVT screw needs to be installed at its head end, and the VVT screw has a clear tightening torque requirement. When tightening, a special fixture is required to clamp the outside of the hexagon from top to bottom and clamp it, so that the torque wrench at the head end can withstand the torque when tightening the screw. At this time, if the angle between the tail slot and the hexagon exceeds the tolerance, then the special fixture will not be able to be clamped into the hexagon and clamped, resulting in the VVT screw not being able to be tightened to the specified torque, and further the assembly of the camshaft fails. At the same time, as a position sensor of the camshaft in the engine, the signal wheel is used to accurately transmit the rotational speed signal of the camshaft and the position of the top dead center of the first cylinder compression to the electronic control module, so as to control the operation of the engine. When the signal wheel angle is abnormal, engine misfiring or abnormal engine output power may occur.
[0004] Therefore, the angles of the tail-end keyway relative to the hexagon and the signal wheel are crucial for the camshaft and must be guaranteed to be accurate by 100%. At present, generally, the angular tolerance between the head-end hexagon and the tail-end keyway is ±2°, and the angular tolerance between the signal wheel and the tail-end keyway is ±0.5°.
[0005] However, the conventional measurement method is to use a coordinate measuring device to collect the coordinate points of the tail-end keyway position, the hexagon position, and the signal wheel tooth surface position respectively, and then evaluate after forming a reference plane, which results in very low detection efficiency of the camshaft and cannot meet the requirements of batch production detection every day. Content of the Utility Model
[0006] The purpose of the utility model is to provide a relative angle inspection tool for a camshaft, which can simultaneously detect the angles of the tail-end keyway relative to the hexagon and the signal wheel, and has the advantages of ingenious structure, convenient use, high detection efficiency, and low cost.
[0007] The technical solution of the present utility model to solve the above technical problems is: A relative angle gauge for a camshaft, including an annular main body. A positioning key for positioning and clamping connection with the keyway at the tail end is provided on the inner ring side of the annular main body. A hexagonal detection notch corresponding to the casting parting line of the camshaft is provided on the annular surface of the annular main body. A signal wheel detection boss for positioning and clamping connection with the notch of the signal wheel is further provided on the outer edge of the annular main body.
[0008] As a further improvement of the present utility model, the signal wheel detection boss includes a first signal wheel detection boss and a second signal wheel detection boss.
[0009] As a further improvement of the present utility model, there are two first signal wheel detection bosses, and the two first signal wheel detection bosses are arranged in sequence along the outer edge of the annular main body.
[0010] As a further improvement of the present utility model, there are two second signal wheel detection bosses, and the two second signal wheel detection bosses are arranged in sequence along the outer edge of the annular main body.
[0011] As a further improvement of the present utility model, the side surface of the positioning key that is in clamping fit with the keyway at the tail end has a taper.
[0012] As a further improvement of the present utility model, the inner ring side of the annular main body is a positioning hole for sleeving and fitting with the outer side of the convex at the tail end of the camshaft.
[0013] As a further improvement of the present utility model, one end of the hexagonal detection notch close to the inner ring side of the annular main body is communicated with the inner ring side of the annular main body.
[0014] As a further improvement of the present utility model, there are two hexagonal detection notches, and the two hexagonal detection notches are respectively arranged on both sides of the center of the annular main body.
[0015] Beneficial effects
[0016] Compared with the prior art, the advantages of a relative angle gauge for a camshaft of the present utility model are as follows:
[0017] 1. By means of the principle that the casting has a parting line, this gauge indirectly determines the angle of the keyway at the tail end relative to the hexagon by detecting the angle between the keyway at the tail end and the parting line of the camshaft. At the same time, the position of the signal wheel is close to the keyway at the tail end. Therefore, by designing a signal wheel detection boss on the gauge, the angle relationship between the keyway at the tail end and the signal wheel can be incorporated into the detection together.
[0018] With this gauge, the staff no longer needs to use a coordinate measuring device to perform multiple point sampling and quantitative detection on the camshaft. Moreover, this gauge can simultaneously detect the angles of the keyway at the tail end relative to the hexagon and the signal wheel, and has the advantages of ingenious structure, convenient operation, high detection efficiency, and low cost.
[0019] The present utility model will become clearer through the following description in conjunction with the accompanying drawings, which are used to explain the embodiments of the present utility model. Description of the Drawings
[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.
[0021] Figure 1 One of the three-dimensional views of the present utility model;
[0022] Figure 2 Another three-dimensional view of the present utility model;
[0023] Figure 3 The use state diagram of the present utility model.
[0024] Wherein: 1 - annular main body; 2 - first signal wheel detection boss; 3 - second signal wheel detection boss; 4 - hexagonal detection notch; 5 - positioning key; 6 - positioning hole. Detailed Embodiment
[0025] In order to make the purpose, technical solutions and advantages of the present utility model clearer, the following further details the present utility model in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts belong to the scope of protection of the present utility model.
[0026] In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; of course, it can also be a mechanical connection or an electrical connection; in addition, it can also be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0027] Now refer to the accompanying drawings to describe the embodiments of the present utility model.
[0028] Embodiment
[0029] The specific implementation manner of the present utility model is as Figures 1-3As shown in the figure, a relative angle gauge for a camshaft includes an annular main body 1, which is coaxial with the camshaft during use and is detachably installed at the tail end of the camshaft. Specifically: a positioning key 5 for positioning and clamping with the tail-end keyway is provided on the inner ring side of the annular main body 1; a hexagonal inspection notch 4 corresponding to the casting parting line of the camshaft is provided on the annular surface of the annular main body 1; a signal wheel inspection boss for positioning and clamping with the notch of the signal wheel is further provided on the outer edge of the annular main body 1.
[0030] During use, just sleeved the gauge onto the tail end of the camshaft to be measured, align the positioning key 5 of the gauge with the tail-end keyway and snap it in. If the signal wheel inspection boss can also be smoothly snapped into the notch of the signal wheel at this time, the angular tolerance of the tail-end keyway relative to the signal wheel meets the requirements; if not, the angular tolerance of the tail-end keyway relative to the signal wheel does not meet the requirements. At the same time, observe the hexagonal inspection notch 4 to see if the casting parting line of the camshaft is in the hexagonal inspection notch 4. If the casting parting line is in the hexagonal inspection notch 4, the angular tolerance of the tail-end keyway relative to the hexagon meets the requirements; if the casting parting line is not in the hexagonal inspection notch 4, the angular tolerance of the tail-end keyway relative to the hexagon does not meet the requirements.
[0031] Based on the principle that there is a parting line in the casting, the gauge indirectly determines the angle of the tail-end keyway relative to the hexagon by detecting the angle between the tail-end keyway and the casting parting line of the camshaft - this is because the angular relationship between the hexagon and the parting line has been ensured during the development of the casting mold, and the parting line (or parting surface) is parallel to two of the planes of the hexagon, that is, the hexagon and the parting line always remain in the same position after the casting is produced. Due to the casting principle and characteristics, there is always a parting line on the casting and it can not be machined off later, so the angle between the tail-end keyway and the parting line can be cleverly used to indirectly evaluate the angle between the tail-end keyway and the hexagon. At the same time, the position of the signal wheel is close to the tail-end keyway, so by designing a signal wheel inspection boss on the gauge, the angle relationship between the tail-end keyway and the signal wheel can be included in the detection together.
[0032] With this gauge, the staff no longer needs to use a coordinate measuring device to take multiple points and quantitative detections on the camshaft, changing the original detection method with a long detection cycle and requiring quantitative analysis into a detection method with a short detection cycle and qualitative detection. The detection time is at least 5 times faster than before, and it can quickly determine whether the angles between the tail-end keyway and the hexagon and the signal wheel are qualified. Moreover, this gauge has the ability to simultaneously detect the angles of the tail-end keyway relative to the hexagon and the signal wheel, and has the advantages of ingenious structure, convenient operation, high detection efficiency and low cost.
[0033] In this inspection tool, the signal wheel detection bosses include a first signal wheel detection boss 2 and a second signal wheel detection boss 3. The first signal wheel detection boss 2 and the second signal wheel detection boss 3 have different sizes and can be respectively positioned and clamped with the notches of signal wheels of different sizes, ensuring the accuracy of detection. In this embodiment, there are two first signal wheel detection bosses 2, and the two first signal wheel detection bosses 2 are arranged in sequence along the outer edge of the annular body 1. There are two second signal wheel detection bosses 3, and the two second signal wheel detection bosses 3 are arranged in sequence along the outer edge of the annular body 1.
[0034] One side surface of the positioning key 5 of this embodiment, which is in clamping fit with the tail-end keyway, has a taper. Designing a taper on part of the positioning key 5 can eliminate the influence of the relative clearance caused by machining errors between the positioning key 5 and the keyway during detection. At the same time, designing the positioning key 5 with a taper can ensure that the positioning key 5 fits completely with the keyway, thus ensuring the detection accuracy. Moreover, in order to enable the inspection tool to be positioned and installed quickly and accurately, the inner ring side of the annular body 1 is a positioning hole 6 that is sleeved and fitted with the outer side of the tail-end protrusion of the camshaft.
[0035] One end of the hexagonal inspection notch 4 of this embodiment, which is close to the inner ring side of the annular body 1, is communicated with the inner ring side of the annular body 1. At the same time, there are two hexagonal inspection notches 4, and the two hexagonal inspection notches 4 are respectively arranged on both sides of the center of the annular body 1. The hexagonal inspection notch 4 is obtained by converting according to the tolerance of ±2° required by the drawing, that is, the notch is a fan-shaped area of ±2°, and the tolerance can also be compressed to ±1.5° for evaluation to eliminate the influence brought by detection errors.
[0036] The above describes the present utility model in combination with the best embodiment, but the present utility model is not limited to the disclosed embodiment above, and should cover various modifications and equivalent combinations made according to the essence of the present utility model.
Claims
1. A relative angle gauge for a camshaft, characterized in that: The invention comprises an annular body (1), wherein the inner ring side of the annular body (1) is provided with a positioning key (5) which is positioned and snap-fitted with a keyway at the tail end, the annular surface of the annular body (1) is provided with a hexagonal detection notch (4) which corresponds to the casting parting line of the camshaft, and the outer edge of the annular body (1) is also provided with a signal wheel detection boss which is positioned and snap-fitted with a notch of a signal wheel.
2. The relative angle gauge for a camshaft according to claim 1, characterized in that: The signal wheel detection boss comprises a first signal wheel detection boss (2) and a second signal wheel detection boss (3).
3. The relative angle gauge for a camshaft according to claim 2, characterized in that: There are two first signal wheel detection bosses (2), and the two first signal wheel detection bosses (2) are arranged in sequence along the outer edge of the annular main body (1).
4. The relative angle gauge for a camshaft according to claim 2 or 3, characterized in that: There are two second signal wheel detection bosses (3), and the two second signal wheel detection bosses (3) are arranged in sequence along the outer edge of the annular main body (1).
5. The relative angle gauge for a camshaft according to claim 1, characterized in that: The side surface of one side where the positioning key (5) is snap-fitted with the tail end keyway has a taper.
6. The relative angle gauge for a camshaft according to claim 1 or 5, characterized in that: The inner ring side of the annular body (1) is a positioning hole (6) that is sleeve-fitted with the outer side of the protrusion at the rear end of the camshaft.
7. The relative angle gauge for a camshaft according to claim 1, characterized in that: One end of the hexagonal detection notch (4) close to the inner ring side of the annular body (1) is connected to the inner ring side of the annular body (1).
8. The relative angle gauge for a camshaft according to claim 1 or 7, characterized in that: There are two hexagonal detection slots (4), and the two hexagonal detection slots (4) are respectively arranged on both sides of the center of the annular body (1).