JP3466099B2 - Sprocket coupling device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sprocket connecting device used in an engine firing device or the like.

[0002]

2. Description of the Related Art In a firing device used for engine load tests and the like (for example, see Japanese Patent Laid-Open No. 58-18140), a sprocket provided on an output shaft of an engine is provided on an input shaft of a measuring machine. It is designed to be coupled to a joint, and as this coupling structure, there is known a configuration in which a corrugated recess along the outer peripheral shape of the sprocket is provided in the joint and the sprocket is fitted into this recess.

[0003]

By the way, in the above-mentioned conventional example, the wall surface of the joint facing the recess is corrugated, but a slight clearance is inevitably formed between this wall surface and the tooth portion of the sprocket. is necessary. Therefore, if the rotation of the sprocket becomes irregular, noise will occur between the sprocket and the joint, and reduction of such noise has been desired. In particular, in the firing device, there is a demand for discovering an abnormal noise of the engine for the purpose of inspection, and thus there has been an urgent demand for such noise reduction.

[0004]

To solve the above problems, a first invention relating to a sprocket coupling device of the present application is a sprocket coupling device including a cup-shaped joint having a fitting recess for fitting a sprocket. At
In the fitting recess of the joint, a plurality of tapered tooth fixing portions that are in close contact with the teeth of the sprocket are provided at equal intervals in the circumferential direction.

A second invention is the same as the first invention,
The tooth fixing portion is a member having a tapered head portion.

A third invention is the same as the first invention,
The tooth fixing portion is a rod-shaped member attached to the joint with its axis inclined with respect to the rotation axis of the sprocket.

A fourth invention is the same as the first invention,
The tooth fixing portion is a tapered wall portion integrally formed in the fitting recess of the joint.

A fifth invention is characterized in that, in any one of the first to fourth inventions, the joint is provided in a firing device.

[0009]

According to the first aspect of the present invention, when the sprocket is fitted in the coupling recess, some of the teeth of the sprocket come into contact with the tooth fixing portions provided at appropriate intervals in the circumferential direction. However, since the tooth fixing portion has a tapered shape, the tooth portions come into close contact with each other, and as a result, the sprocket and the joint are joined without play. Therefore, even if the sprocket rotates irregularly, noise is less likely to be generated between the sprocket and the joint, and the noise at the joint can be reduced.

According to the second aspect of the invention, since the tooth fixing portion is a member having a tapered head portion, this member can be attached to the joint in parallel with the rotation axis of the sprocket, so that the tooth fixing portion is attached. Will be easier.

In the third aspect of the invention, since the rod-shaped member is attached to the joint so that the axis of the sprocket is inclined with respect to the rotation axis of the sprocket, the tooth fixing portion having the tapered portion can be easily provided and the rod-shaped member can be easily provided. The shape of can be simplified.

According to the fourth aspect of the invention, since the tapered wall portion is formed integrally with the wall surface facing the fitting recess of the joint, this wall portion serves as a tooth fixing portion having the tapered portion, and when the sprocket is fitted. The teeth can be brought into close contact with each other. In addition, the number of parts is reduced by providing the joint integrally, and the joint is easily manufactured.

According to a fifth aspect of the present invention, since any one of the above tooth fixing portions is provided in the joint of the firing device, a joining structure suitable for the firing device is provided, particularly when the generation of noise at the joining portion of the sprocket and the joint is disliked. Obtainable.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment will be described below with reference to the drawings. 1 to 3 relate to a first embodiment applied to a firing device, FIG. 1 is a cross-sectional view showing a joint structure of a joint and a sprocket, and FIG. 2 is a view showing a measuring machine side portion of the firing device. 3 is a sectional view taken along line 3-3 of FIG.

First, as shown in FIG. 2, in the measuring machine side portion of this firing device, an input shaft 2 having a joint 1 attached to one end is connected to a torque meter 3 and further connected to a pump motor 4. The portion of the input shaft 2 where the joint is mounted projects from the cover 5 of the device, and the positioning rod 6 also projects in parallel with this.

The positioning rod 6 is inserted into an engine mount mounting hole 8 (FIG. 3) of a completed engine 7 configured for a motorcycle, for example,
The joint 1 and the engine 7 are positioned. In this state, the joint 1 is connected to the sprocket 10 attached to the output shaft 9.

The engine 7 is fixed on a support base (not shown) which constitutes a firing device. A throttle-controlled air supply device is connected to the intake side of the engine and an exhaust side of the engine is connected to the exhaust side. By connecting a duct and by interlocking the input shaft 2 with a brake device, it is possible to inspect engine startability and brake performance by a load test.

1 and 3 show details of the joint structure of the joint 1 and the sprocket 10. The joint 1 is cup-shaped, and the inner side of the peripheral wall portion 12 surrounding the fitting recess 11 for fitting the sprocket 10 therein. A plurality of tooth fixing portion mounting holes 13 are provided at equal intervals along a concentric circle (in this embodiment, three holes are provided at 120 ° intervals).

The tooth fixing portion mounting hole 13 is formed in the sprocket 1
An accommodating recess 1 for a bolt head formed parallel to the center line C of the output shaft 9 which is a 0 rotation shaft and carved to the bottom 14 and formed on the step 15 side provided on the outer peripheral side of the bottom 14
It communicates with 6. An input shaft mounting hole 17 is formed through the center of the bottom portion 14, the center of the input shaft mounting hole 17 is formed coaxially with the center line C of the output shaft 9, and the inner peripheral surface is provided with a spline groove. Are formed.

The tooth fixing portion mounting hole 13 is provided with a tooth fixing portion 20 which is a member having a tapered head portion having a substantially mushroom shape as a whole. The number of the tooth fixing portion 20 is arbitrary, but the tooth fixing portion mounting hole 13 is provided. Corresponding to the above, in this embodiment, 3 at 120 ° intervals.
Individually arranged.

The tooth fixing portion 20 is provided with a tapered head portion 21 having an umbrella shape of a mushroom and a shaft portion 22 following the head portion. The shaft portion 22 is inserted into the tooth fixing portion mounting hole 13 and is provided in advance at the tip thereof. With respect to the screw hole 23, the accommodation recess 1 of the bolt head
It is integrated with the bottom portion 14 by fastening a bolt 24 inserted from 6.

The tapered head portion 21 has an inclination of an inclination angle α with respect to the center line C of the output shaft 9, and the sprocket 10
Is inclined so as to intersect with the center line C of the output shaft 9 in the fitting direction, and the periphery thereof enters the tooth groove 10b of the tooth portion 10a, and the base side is larger than the tooth groove 10b, and a part of the surface is A part of the tooth portion 10a, for example, the tooth bottom 10c is closely contacted.

A spline portion 30 formed at one end portion of the input shaft 2 is fitted in the input shaft mounting hole 17 of the bottom portion 14 and is prevented from coming off by a circlip 31. Further, the spline portion 30 is formed. An axial elongated hole 32 is formed in the portion, and a pin 33 is inserted from the joint 1 side into the elongated hole 32.

For this reason, the joint 1 can rotate integrally with the input shaft 2, and within the length range of the slot 32, the input shaft 2 can be rotated.
It is free to move in the axial direction. However, the flange portion 34 and the step portion 15 that are integrally rotatable around the input shaft 2 are provided.
A coil spring 35 disposed between and compressed to move and urge the shaft 2 toward the shaft end of the input shaft 2.

Next, the operation of this embodiment will be described. When the sprocket 10 is fitted into the fitting recess 11 of the joint 1, the tapered head portion 21 of the tooth fixing portion 20 enters the tooth groove 10b. Moreover, the joint 1 is the coil spring 3
Since it is urged to move toward the sprocket 10 by means of 5, the tapered head 21 is provided with a tooth portion 10 of the sprocket 10.
It is pressed against a.

Then, since the surface of the tapered head portion 21 has an inclination of an inclination angle α so as to intersect with the center line C of the output shaft 9 in the fitting direction of the sprocket 10, the tooth on any part of the base side surface thereof. Part of the portion 10a, for example, the tooth bottom 10
It abuts c and is pressed tightly in this part.

Moreover, as is apparent from FIG. 3, since the tooth fixing portions 20 are provided at 120 ° intervals, the sprocket 10 is securely fixed to the joint 1 at the three points, and the sprockets 10 are joined together without play. Even if the sprocket 10 and the output shaft 9 are coaxially centered and the rotation of the sprocket 10 is irregular, noise is less likely to occur between the sprocket 10 and the joint 1, so that the noise at the joint can be reduced.

Further, since the tooth fixing portion 20 is shaped like a mushroom-shaped headed pin, the tooth fixing portion 20 can be mounted parallel to the output shaft 9, that is, perpendicular to the rotation surface of the joint 1, so that the mounting work becomes easy. In addition, if it is desired to change the degree of taper, it is possible to easily replace the taper head 21 with another one having a different inclination angle α.

Further, if this coupling structure or the coupling structure in another embodiment described below is adopted in the firing device, it is possible to inspect for abnormal noise of the engine 7 without being disturbed by noise at the coupling portion of the sprocket 10 and the joint 1. The coupling structure is suitable for a device that dislikes this kind of noise.

FIG. 4 relates to the second embodiment, and is a view similar to FIG. 1 showing the coupling structure of the sprocket 10 and the joint 1 used in the firing device similar to the previous embodiment. It should be noted that common functional parts and those of the previous embodiment use common symbols, and the differences will be mainly described below.

The tooth fixing portion 20 in the present embodiment is a rod-shaped member having a single shape, and the one end portion 40 is fixed to the bottom portion 14 while keeping the entire axis C1 at an angle of inclination α. For this fixing structure, various known methods such as press fitting can be adopted.

In this way, the other end 41, which is the free end side, is not a tapered head portion, but since this entire portion has a taper shape inclined with respect to the central axis C, it is also in the tooth groove 10b. Since the sprocket 10 and the joint 1 are inserted into each other and are joined together without play, the same effect as that of the previous embodiment can be obtained with respect to noise, and the tooth fixing portion 20 has a simple rod shape, so that the shape can be simplified.

5 and 6 relate to a third embodiment applied to a firing device similar to the previous embodiments, and FIG.
6 is a cross-sectional view (however, showing the entire cross-section) showing a portion corresponding to line 6-6 in FIG. In the tooth fixing portion 20 of this embodiment, tapered wall portions 50 are integrally formed on the inner surface of the peripheral wall 12 facing the fitting recess 11 at intervals of 120 ° in the circumferential direction.

The tapered wall portion 50 also has an inclination angle α, and one tooth portion 10a is formed as a bottom portion of a concave groove 51 which can be fitted with a clearance on the inlet side, and the concave groove 51 is fitted. It is provided in a bulging portion 52 formed to project from the peripheral wall 12 into the recess 11.

In this way, even if the inlet side of the recessed groove 11 is wide enough to have a clearance, the tips of the tooth portions 10a that have entered the recessed groove 51 come into contact with the tapered wall portion 50 and press it tightly. Since it will be in the state where it is set, it is possible to join without backlash.

It will be more effective if at least one of the side walls 53 facing the groove 51 is tapered so that the width of the groove 51 becomes gradually narrower in the depth direction. Further, the number of the concave grooves 51 is arbitrary as long as it is plural, and all the tooth portions 10
You may provide only the number corresponding to a.

According to the structure of this embodiment, since the tapered wall portion 50 as the tapered portion can be formed integrally with the joint 1, the number of parts can be reduced and the joint having the tapered portion can be easily manufactured.

The invention of the present application is not limited to the above-described embodiment, and various applications are possible. For example, the object of application of this joint is not limited to the firing device, and sprockets can be joined by fitting without play. Any device may be used as long as the device requires the. Further, instead of the coil spring 35, another type of elastic member such as a disc spring or a rubber block can be used.

[Brief description of drawings]

FIG. 1 is a sectional view showing a joint and sprocket coupling structure according to a first embodiment.

FIG. 2 is a view showing a measuring machine side portion of the firing device.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is similar to FIG. 1 according to the second embodiment.

5 is similar to FIG. 1 according to the third embodiment.

6 is a cross-sectional view showing a portion corresponding to line 6-6 in FIG.

[Explanation of symbols]

1: joint, 2: input shaft, 7: engine, 10: sprocket, 11: fitting recess, 12: peripheral wall part, 20: tooth fixing part, 21: tapered head part, 35: coil spring, 50: taper shape Wall part, 51: concave groove

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-8-247381 (JP, A) JP-A-58-18140 (JP, A) JP-A-6-109597 (JP, A) SAIKAI HEI 4- 56923 (JP, U) Actual Kaihei 3-37284 (JP, U) Actual public 16-5350 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16D 1/02 G01M 15 / 00

Claims (5)

(57) [Claims] 1. A sprocket coupling device including a cup-shaped joint having a fitting recess for fitting a sprocket, wherein a tapered tooth fixing portion is in close contact with a tooth portion of the sprocket in the fitting recess of the joint. A sprocket connecting device characterized in that a plurality of sprocket connecting devices are provided at equal intervals in the circumferential direction. 2. The sprocket connecting device according to claim 1, wherein the tooth fixing portion is a member having a tapered head portion. 3. The sprocket coupling device according to claim 1, wherein the tooth fixing portion is a rod-shaped member attached to a joint with an axis inclined with respect to a rotation axis of the sprocket. 4. The sprocket connecting device according to claim 1, wherein the tooth fixing portion is a tapered wall portion integrally formed in the fitting recess of the joint. 5. The sprocket coupling device according to claim 1, wherein the joint is provided in a firing device.