Railway vehicle traction gear meshing test method

Abstract

The invention relates to the related technical field of rail transit vehicles, in particular to a rail vehicle traction gear meshing test method, which comprises the following steps of: firstly, calculating an actual meshing interval value, enabling an actual meshing-in and meshing-out position to generate additional displacement on a meshing interval due to a meshing-in and meshing-out gap, moving a meshing-in point from an original A point to a F point, at the moment, when the meshing interval variable quantity is # imgabs0 # and the meshing is quitted in the same way, the meshing interval variable quantity is # imgabs1 #, the actual meshing interval length is changed from # imgabs2 # to # imgabs3 #, parallel calculation is carried out, and then the numerical value of # imgabs4 # is calculated in a column formula; the number N of tooth pairs participating in meshing at the same time is calculated, finally, the calculated number N of tooth pairs participating in meshing at the same time is compared with a set meshing tooth pair number reference index n, and finally, a detection result for whether meshing of the traction gear of the railway vehicle is qualified or not is obtained. According to the rail vehicle traction gear meshing test method, the actual meshing tooth pair number of the gear teeth can be determined by analyzing the gear edge trimming amount and the driving and driven gear tooth crest edge trimming amount.

Description

Technical Field

[0001] The invention belongs to the technical field related to rail transit vehicles, and particularly relates to a method for inspecting the meshing of traction gears of rail vehicles. Background Technique

[0002] The traction gear is an important transmission component of rail vehicles, which is used to transmit the torque of the traction motor to the wheelset, and then drive the vehicle to run. Its meshing quality directly affects the transportation load-bearing capacity and running stability of the vehicle. At present, the average value of the number of pairs of teeth in simultaneous meshing is commonly used to measure the meshing quality of gear transmission. When the gears mesh, deformation will occur. Therefore, in order to reduce the meshing impact and improve the load-bearing capacity, the traction gears of rail vehicles often adopt the design of tooth tip relief (thinning the tooth tip) during design. The design of the relief amount is usually based on the meshing deformation amount of the teeth under a certain speed condition. When the vehicle runs at high speed, the output torque of the traction motor decreases. At this time, the reduction of the deformation amount will lead to the shortening of the meshing interval, greatly reducing the actual number of meshing teeth.

[0003] At present, the theoretical calculation method cannot calculate the actual number of meshing teeth under different speed (load) conditions and different relief amounts. The invention determines a method for inspecting the meshing of traction gears of rail vehicles by analyzing the basic mechanism of gear relief and the determination method of the tooth tip relief amounts of the driving and driven gears, and based on the change of the actual meshing interval before and after relief. This method fully considers the influence of different loads and different relief amounts on the meshing interval, improves the calculation accuracy of the actual number of meshing teeth, and provides an accurate and feasible method for inspecting the tooth tip relief amount and meshing quality. Summary of the Invention

[0004] The purpose of the invention is to provide a method for inspecting the meshing of traction gears of rail vehicles by analyzing gear relief and the tooth tip relief amounts of the driving and driven gears, so as to determine the actual number of meshing teeth of the teeth.

[0005] To achieve the above purpose, the invention provides the following technical solution: A method for inspecting the meshing of traction gears of rail vehicles, including the following steps:

[0006] Step S1: First calculate the value of the actual meshing interval. Due to the meshing-in and meshing-out clearances at different working conditions, the actual meshing-in and meshing-out positions have additional displacements on the meshing interval. The meshing-in point moves from the original A to point F. At this time, the change amount of the meshing interval is Similarly, when disengaging from meshing, the change amount of the meshing interval is The length of the actual meshing interval changes from to Then the parameter The value is calculated according to the following formula:

[0007]

[0008] Where: Point C is the intersection of the pitch circles of the driving and driven gears; is the change amount of the meshing interval from C to point F; is the change amount of the meshing interval from C to point H;

[0009] Step S2: The calculation of the and is calculated according to the geometric relationship, and the calculation formula is as follows:

[0010]

[0011] Where: r x1 and r x2 are the radii of the actual engagement and disengagement points of the driving and driven gears respectively; r b1 , r b2 are the base circle radii of the driving and driven gears respectively; α0 is the engagement angle;

[0012] Step S3: According to the results of the above Step S1 and Step S2, calculate the number of teeth pairs N actually engaged simultaneously:

[0013]

[0014] Where: m is the module; L is the actual meshing interval of the tooth; P is the normal tooth pitch of the tooth base circle.

[0015] Step S4: To ensure the smoothness of the traction gear during high-speed operation, considering the actual working conditions and machining error factors, set the benchmark index n of the number of meshing teeth pairs as the minimum value for evaluating the meshing quality. If the number of meshing teeth pairs is greater than or equal to n, it is evaluated as qualified; otherwise, it is evaluated as unqualified.

[0016] As a further improvement of the present invention, the calculation of the radii r x1 and r x2 of the engagement and disengagement points during actual meshing in Step S2 is specifically carried out according to the following steps:

[0017] Step S201: First, calculate the reduction height Δh of the meshing point. After crowning, the engagement and disengagement points will change in the tooth height direction, that is, the meshing point will move downward from the tooth tip, as shown in Figure 3 where s is the sum of the meshing deformation x of the tooth and the base pitch error f before a certain working condition. During meshing, the engagement and disengagement points change from point A at the tooth tip to point B. From the Figure 3 geometric relationship in, establish an approximate function of the crowning amount and the deformation amount:

[0018]

[0019] Where: s is the sum of the meshing deformation x and the base pitch deviation f; δ is the crowning amount of the driven gear tooth tip; h i is the meshing point height from point B to point C; h is the crowning height of the tooth;

[0020] Therefore, it can be known that the reduced height Δh of the meshing point is calculated by the following formula:

[0021]

[0022] Where: h is the height of tooth tip modification, and hi is the height of the meshing point;

[0023] Step S202: Then calculate the radius r of the meshing-in and meshing-out points during actual meshing by using the following formula x1,2 :

[0024]

[0025] Where: r is the radius of the addendum circle; r x1,2 is the radius of the actual meshing start and end points (meshing-in and meshing-out points).

[0026] As a further improvement of the present invention, the specific value of the set number of meshing tooth pairs index n in the step S4 is 1.2.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: By analyzing the tooth tip modification situation of the gear, based on the change law of the actual meshing interval before and after the modification, a calculation method for the actual number of meshing tooth pairs of the tooth profile is determined; According to the relationship between the meshing deformation amount and the modification amount of the tooth profile under different working conditions, the change amount of the meshing-in and meshing-out points in the tooth height direction under different working conditions after the modification is determined, and according to the geometric relationship formula, a calculation method for the actual meshing interval and the actual number of meshing tooth pairs is determined; The method of the present technical solution fully considers the influence of the modification amount on the meshing interval, has practical value for inspecting the tooth tip modification and evaluating the meshing quality, and provides an accurate method for improving the gear design and evaluating the gear meshing quality. Brief Description of the Drawings

[0028] Figure 1 It is a schematic diagram of the actual meshing interval of the tooth profile of the present invention.

[0029] Figure 2 It is a schematic diagram of the meshing clearance after the modification of the present invention.

[0030] Figure 3 It is a schematic diagram of the change in the position of the meshing point of the present invention.

[0031] The symbols in the drawings are explained as follows:

[0032] The change amount of the actual meshing interval of the tooth profile; Point C: The intersection point of the pitch circles of the driving and driven gears; r b1、 r b2： are the base circle radii of the driving and driven gears respectively; r A1 : The root circle radius of the driving gear; r A2：: Addendum circle radius of the driven gear; r E1 : Addendum circle radius of the driving gear; r E2 : Root circle radius of the driven gear; α a1 and α a2 are the addendum circle pressure angles of the driving and driven gears respectively; α0: Contact angle; W1: Rotational speed of the driving gear, W2: Rotational speed of the driven gear; S: Sum of the meshing deformation x of the tooth profile and the base pitch error f before different working conditions; x: Meshing deformation; δ: Tooth tip relief amount, h i : Height from the meshing point to the starting point of the relief; r: Addendum circle radius; r x1,2 : Radii at the starting and ending points of meshing; A: Tooth tip meshing point; B: Tooth tip meshing point. Specific embodiments

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] Please refer to Figures 1 to 3 , the specific embodiments of the present invention are described as follows:

[0035] 1) Method for evaluating the meshing quality of gear teeth: The present invention takes the number of gear teeth N that are simultaneously engaged as an important index for evaluating the meshing quality of gear teeth. The ratio of the actual meshing interval L of the gear teeth to the normal base pitch P of the gear teeth is the number of gear teeth N that are simultaneously engaged: N = L / P.

[0036] The actual meshing interval L of the same pair of gear teeth changes with the operating conditions. Therefore, the value of the number of gear teeth N that are simultaneously engaged under different operating conditions is different. The value of N when the traction gear of the rail vehicle runs at high speed is used as an index for evaluating the meshing quality, and it is stipulated that N under this condition is greater than or equal to 1.2.

[0037] 2) Calculation of the effective meshing interval of gear teeth: The meshing transmission interval of a pair of gear pairs is limited. As Figure 1 shown in the schematic diagram of the meshing interval of two gears meshing, where is the actual meshing interval of the gear teeth, C is the intersection point of the pitch circles of the driving and driven gears, r b1、 r b2 are the base circle radii of the driving and driven gears respectively, r A1 is the root circle radius of the driving gear, r A2 is the addendum circle radius of the driven gear, r E1 is the addendum circle radius of the driving gear, r E2 is the root circle radius of the driven gear. As Figure 1 Effective meshing interval:

[0038]

[0039] According to the geometric relationship, where:

[0040]

[0041] In the formula: α a1 and α a2 are the addendum circle pressure angles of the driving and driven gears respectively, and α a0 is the contact angle.

[0042] 3) Variation of the tooth engagement interval: The tip relief amount of the traction gear of the rail vehicle is the sum of the meshing deformation amount x and the base pitch deviation f under a certain speed condition. In the high-speed condition, due to the reduction of the traction force, the deformation amount of the front pair of teeth when the teeth engage is smaller than the tip relief amount of the driven gear, so the engagement will be delayed; similarly, the tip relief of the driving gear will cause the teeth to disengage earlier in the high-speed condition. The meshing and disengagement clearances after tip relief are as Figure 2 shown.

[0043] The actual meshing and disengagement positions have additional displacements in the engagement interval due to the meshing and disengagement clearances, resulting in a change in the engagement interval. Figure 1 The meshing-in point moves from the original point A to point F. At this time, the variation of the engagement interval is Similarly, when disengaging, the variation of the engagement interval is The actual length of the engagement interval changes from to

[0044] 4) Calculation of the actual length of the meshing line

[0045] After tip relief, the meshing-in and disengagement points will change in the tooth height direction, that is, the meshing point will move downward a certain distance from the tooth tip. As in Figure 3 where s is the sum of the meshing deformation amount x and the base pitch error f of the front pair of teeth under different working conditions. The starting and ending points of meshing change from point A at the tooth tip to point B. Let the tip relief amount of the driven gear be δ, and r’ x is the radius at point C. The meshing deformation amount is x, and s = x + f. Based on this, the height h i of the meshing point and the radius rx of the meshing point can be calculated. From Figure 3 the geometric relationship, an approximate function of the tip relief amount and the deformation amount is established:

[0046]

[0047] Therefore, it can be known that the reduced height of the meshing point is:

[0048]

[0049] Where s is the sum of the meshing deformation and the base pitch deviation, h is the tip relief height, and hi is the height of the meshing point. Then calculate the radii r of the actual meshing start and end points (engagement and disengagement points). x1,2 , that is, calculate the radii r of the actual meshing start and end points (engagement and disengagement points) during actual meshing respectively x1 and r x2 :

[0050]

[0051] Where: r is the addendum circle radius; r x1,2 is the radius of the actual meshing start and end points.

[0052] Figure 1 In the actual meshing interval

[0053]

[0054] According to the geometric relationship, where:

[0055]

[0056]

[0057] Where: r x1 and r x2 are the radii of the actual engagement and disengagement points of the driving and driven gears respectively; r b1 , r b2 are the base circle radii of the driving and driven gears respectively; α0 is the pressure angle.

[0058] 5) Method for evaluating meshing quality

[0059] According to the results of the above steps S1 and S2, calculate the number of teeth pairs N actually participating in meshing:

[0060]

[0061] Where: m is the module.

[0062] Take the actual number of meshing teeth pairs N as an index to evaluate the meshing quality of the teeth. When calculating, first calculate the deformation x of the tooth meshing according to the tooth meshing stiffness and the working condition load; then calculate the radii r x1 and r x2 of the actual meshing start and end points respectively according to the relief amount δ, the relief height h, and the addendum circle radius r; finally calculate the actual number of meshing teeth pairs N according to the base circle radii r b1 , r b2 , the pressure angle α0, and the module m.

[0063] To ensure the smooth operation of the traction gear at high speeds, considering the influence of actual working conditions, machining errors, etc., the number of meshing teeth 1.2 is taken as the minimum value for evaluating the meshing quality. The method of the present invention can improve the deficiency that the theoretical calculation formula does not consider the amount of tip relief, has practical value for inspecting the tip relief of gear teeth and evaluating the meshing quality, and provides an accurate method for improving gear design and evaluating gear meshing quality.

[0064] The above are only the preferred examples of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for inspecting the meshing of traction gears of a railway vehicle, characterized in that: The specific steps include: Step S1: First calculate the actual meshing interval value. Under different working conditions, the meshing clearance causes the actual meshing position to undergo additional displacement in the meshing interval. The meshing point moves from the original point A to point F. At this time, the meshing interval change is Similarly, the change in the meshing interval when exiting meshing is The actual meshing interval length is given by becomes Then the parameter The value is calculated according to the following formula: In the formula: Point C is the intersection point of the master and driven gear pitch circles; is the change in the meshing interval from point C to point F; is the change in the meshing interval from point C to point H; Step S2: and According to the geometric relationship, the calculation formula is as follows: Where: r x1 and r x2 are the actual meshing point radius of the driving and driven gears respectively; r b1 、r b2 are the base circle radii of the driving and driven gears respectively; α0 is the meshing angle; Step S3: According to the results of step S1 and step S2, the number of tooth pairs N actually participating in the meshing at the same time is calculated: Where: m is the module; L is the actual meshing range of the gear teeth; P is the normal pitch of the gear tooth base circle. Step S4: To ensure the stability of the traction gear during high-speed operation, the meshing tooth pair number reference index n is set as the minimum value for evaluating the meshing quality in combination with the actual working conditions and processing error factors. If the meshing tooth pair number is greater than or equal to n, it is evaluated as qualified, otherwise it is evaluated as unqualified.

2. A method for inspecting the meshing of traction gears of a railway vehicle according to claim 1, characterized in that: The radius r of the meshing point during actual meshing in step S2 x1 and r x2 The calculation is as follows: Step S201: First calculate the lowered height Δh of the meshing point. After trimming, the meshing point will change in the direction of the tooth height, that is, the meshing point will move downward from the tooth top. As shown in FIG3 , s is the sum of the meshing deformation x and the base pitch error f of the gear teeth before a certain working condition. When meshing, the meshing point changes from point A on the tooth top to point B. Based on the geometric relationship in FIG3 , an approximate function of the trimming amount and the deformation is established: Where: s is the sum of the meshing deformation x and the base pitch deviation f; δ is the tooth tip trimming amount of the driven gear; h i is the meshing point height from point B to point C; h is the tooth trim height; Therefore, the lowered height Δh of the meshing point can be calculated by the following formula: Where: h-tooth trim height, hi-meshing point height; Step S202: Calculate the radius of different meshing points during actual meshing using the following formula: x1,2 : Where: r is the radius of the tooth tip circle; r x1,2 is the actual meshing start and end radius.

3. A method for inspecting the meshing of traction gears of a railway vehicle according to claim 1, characterized in that: In the step S4, the specific value of the meshing tooth pair number index n is set to 1.2.

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