JPH0612048B2 - Eccentric shaft of multi-cylinder rotary piston engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a multi-cylinder rotary piston engine having at least three cylinders, and further,
Specifically, it relates to an eccentric shaft of a multi-cylinder rotary piston engine.

(Prior Art) In a multi-cylinder rotary piston engine, for example, as disclosed in Japanese Utility Model Publication No. 55-14723, when the number of cylinders is 3 or more, the eccentric portion also becomes 3 or more, and one eccentric shaft is provided. It has been proposed that the eccentric shaft is divided into at least two or more parts for assembly because it is difficult to assemble the eccentric part by forming three or more eccentric parts.

In the one disclosed in Japanese Utility Model Publication No. 55-14723, the eccentric shaft is divided into a first eccentric shaft having two eccentric parts and a second eccentric shaft having one eccentric part. The tip portion and the tip portion of the second eccentric shaft are fitted and brought into contact with each other, and the second eccentric shaft is fitted with a bolt in a through hole opened in the eccentric shaft and the bolt is attached to the tip portion of the first eccentric shaft. It is configured to form a threaded portion that is screwed into and to connect the first eccentric shaft and the second eccentric shaft with this bolt. However, since the bolt extends through the engine cylinder, There is a risk that the bolt will be affected by heat, or the bolt will be elongated due to the fastening axial force of the bolt, and the first eccentric shaft and the second eccentric shaft are joined together at their tip end portions, so-called cantilever. Because of the formula, the first eccentric shaft of the second eccentric shaft is affected by the engine vibration. And the distal end of the shaft runout large end remote from the tip that abuts, bolt there is a possibility that breakage has become a difficult practical use.

Further, since the tip end portions are connected only to each other, it is difficult to accurately match the axial center of the first eccentric shaft and the axial center of the second eccentric shaft.

Therefore, a configuration has been proposed in which the second eccentric shaft is fitted and inserted into the first eccentric shaft, and the first eccentric shaft and the second eccentric shaft are spline-coupled to each other. There is a risk of rattling.

(Object of the Invention) The present invention has been made in consideration of the above circumstances, and an object of the present invention is to reliably connect the eccentric shafts together and prevent rattling due to engine vibration. Then
Another object of the present invention is to provide an eccentric shaft for a multi-cylinder rotary piston engine that can easily and accurately match the shaft centers thereof.

(Structure of the Invention) In order to achieve the above object, the present invention has the following structure, that is, a large diameter portion having an eccentric portion on the outer periphery and a small diameter portion having a diameter smaller than the large diameter portion. A first eccentric shaft having a tapered portion formed between the small-diameter portion and the large-diameter portion and expanding in diameter as it extends from the small-diameter portion toward the large-diameter portion; and an eccentric portion on the outer periphery. And has a hollow shape that is fitted to the outer circumference of the small diameter portion, the tapered hole formed in the inner end portion is fitted in the tapered portion, and is located axially opposite to the inner end portion. A second eccentric shaft that is pressed in the direction of the large diameter portion while the outer end portion is pressed into the small diameter portion.

According to this structure, the second eccentric shaft and the first eccentric shaft can be press-fitted to each other and supported as a whole, so that the eccentric shafts can be reliably coupled to each other, and the eccentric shaft can be vibrated by the engine vibration. It is possible to prevent the bond between the two people from loosening. Further, since the second eccentric shaft is fitted and coupled to the small-diameter portion of the first eccentric shaft, the shaft centers of the eccentric shafts can be easily and accurately matched with each other.

(Embodiment) An embodiment of an eccentric shaft of a multi-cylinder rotary piston engine according to the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall structure of a multi-cylinder rotary piston engine to which an eccentric shaft according to the present invention is applied. In FIG. 1, reference numeral 1 denotes a multi-cylinder (3-cylinder) rotary piston engine main body. The cylinder rotary piston engine body 1 has end side housings 2 and 3, intermediate side housings 4 and 5, and rotor housings 6 to 8, and the rotor housing 6 includes the end side housing 2 and the intermediate side housing 4. And the rotor housing 7 is kept airtight by the intermediate side housings 4 and 5 to form the working chamber 9 of the first cylinder.
The working chamber 10 of the cylinder is formed, and the rotor housing 8 is kept airtight by the end side housing 3 and the intermediate side housing 5 to form the working chamber 11 of the third cylinder. It is a passage. Each housing 2
8 are positioned with respect to each other by positioning pins 21 to 23 having a hollow shape, and are joined by being tightened by a tension bolt 24. In FIG. 2, 25 is an insertion hole of the tension bolt 24, 26 is an intake hole, and 27 is an intake hole.
Indicates an exhaust hole.

The multi-cylinder rotary piston engine body 1 is provided with a first eccentric shaft 28 penetrating the multi-cylinder rotary piston engine body 1 from the end side housing 2 toward the end side housing 3. This first eccentric shaft 28
Has a large-diameter portion 29 extending in the axial direction and a small-diameter portion 30 having a smaller diameter than the large-diameter portion 29. Here, the large-diameter portion 29 extends from the end side housing 2 to the intermediate side housing 5. The small diameter portion 30 is configured to extend up to
It is configured to project to the outside from the intermediate side housing 5 via the rotor housing 8 and the end side housing 3. The large-diameter portion 29 has an eccentric portion 31 formed in a portion facing the working chamber 9, and an eccentric portion 32 in a portion facing the working chamber 10.
Is formed, and triangular rotors 33 and 34 as shown in FIG. 2 are attached to the eccentric portions 31 and 32, respectively. Here, a flywheel 36 is attached to the large-diameter end portion 35 of the first eccentric shaft 28, 37 is a ring gear attached to the flywheel, and a small-diameter end portion 38 of the small-diameter portion 30 is attached to the ring gear. The bolt portion 39 is formed and the attached member 40 is attached.

Fixed gears 41, 42, 4 are provided on the end side housing 2, the end side housing 3, and the intermediate side housing 5.
3 are attached by bolts 44, fixed gears 41 and 42 are also configured to serve as bearings for the first eccentric shaft 28, 45 and 46 denote bearings thereof, and 41a to 43a denote fixed gears. The tooth portions 41 to 43 are shown. Each rotor 33, 34 has an internal gear 4
7 and 48 are attached, and the teeth thereof are the teeth 41 of the fixed gear.
The internal gears 47 and 48 are screwed to the a and 42a, and rotate around the fixed gears 41 and 42 together with the rotors 33 and 34 in a planetary manner.

A hollow second eccentric shaft 49 is provided on the small-diameter portion 30 of the first eccentric shaft 28. The second eccentric shaft 49 has a through hole 50 extending in the axial direction thereof as shown in FIG. 3, and the small diameter portion 30 is configured to be fitted into the through hole 50. A taper portion 51 is formed on the first eccentric shaft 28 between the large diameter portion 29 and the small diameter portion 30 as shown in FIG. 4, and the taper portion 51 extends from the small diameter portion 30 to the large diameter portion 2.
9, the diameter of the through hole 50 gradually increases as it extends toward the inner diameter of the through hole 50.
2 is formed, and the taper portion 51 is press-fitted into the taper hole 52. The taper portion 51 and the taper hole 52 are axially positioned by the eccentric portion 53 formed on the second eccentric shaft 49. It functions as. The eccentric portion 53 is located in the working chamber 11 of the third cylinder, and the rotor 54 is attached to the eccentric portion 53.
An internal gear 55 is fixed to the internal gear 55, and its tooth portion is meshed with the tooth portion 43a of the fixed gear 43. The internal gear 55 together with the rotor 54 rotates around the fixed gear 43 as a planet. Here, the fixed gear 43 also serves as the bearing portion of the second eccentric shaft 49, and 56 is its bearing.

The second eccentric shaft 49 is inserted from the small-diameter end portion 38 into the small-diameter portion 30, and between the small-diameter portion 30 and the second eccentric shaft 49, the rotation direction of the eccentric portion 53 of the second eccentric shaft 49. A key 57 is provided for positioning the respective eccentric parts of the first eccentric shaft 28. The second eccentric shaft 49 is tapered in the axial direction of the small diameter portion 30 via the member 40 to be mounted by the nut 58 screwed to the bolt portion 39 formed on the small diameter end portion 38 of the first eccentric shaft 28. The hole 52 is pressed in a direction approaching the tapered portion 51, and here, of the both end portions of the second eccentric shaft 49, the outer end portion on the side far from the inner end portion where the tapered hole 52 is formed. It is configured to project from the end side housing 3 to the outside. The second eccentric shaft 49 is fitted while press-fitting the small-diameter portion 30, and here, the portion near the outer end portion on the side far from the inner end portion where the tapered hole 52 is formed is the press-fitting portion 50a. ,
The press-fitting portion 50a press-fits the small-diameter portion 30. Therefore, the second eccentric shaft 49 is supported by the first eccentric shaft 28 so that the second eccentric shaft 49 cannot rotate relative to the taper hole 52 and the press-fitting portion 50a. The taper hole 52 and the press-fitting portion 50a
Is a non-press-fitted portion 50b that is not press-fitted into the small diameter portion 30 to facilitate the insertion of the second eccentric shaft 49 into the small diameter portion 30, and here, the inner peripheral surface of the tapered hole 52 is provided. Further, in order to prevent relative rotation between the second eccentric shaft 49 and the first eccentric shaft 28 as much as possible, for example, copper plating for increasing the friction coefficient is applied, and the outer peripheral surface of the tapered portion 51 is porous chrome plated, ion-plated. Ceramic coating by the coating method.

Reference numeral 57 'is a key for positioning the attached member 40 (for example, an oil pump drive gear, a balance weight, etc.) in the rotational direction.

Although the embodiment has been described above, the present invention is not limited to this, and includes the following cases, for example.

(A) In the embodiment, the second eccentric shaft 49 is pressed toward the large diameter portion 29 of the first eccentric shaft 28 by the cooperative action of the nut 58 and the bolt portion 39 via the mounted member 40. Instead of the mounted member 40, a collar is interposed between the nut 58 and the second eccentric shaft 49, and the second eccentric shaft 49 is pressed through this collar to be press-fitted into the small diameter portion 30. You can also do it.

Further, the attached member 40 is omitted and the nut 58 directly
The outer end of the eccentric shaft 49 may be pressed.

(B) In this embodiment, the second eccentric shaft 49 is press-fitted only at two axially separated positions, but the second eccentric shaft 49 has its first eccentric shaft 49 over its entire axial direction. Alternatively, the small-diameter portion 30 of 28 may be press-fitted.

(C) In this embodiment, an example in which the eccentric shaft of the present invention is applied to a three-cylinder multi-cylinder rotary piston engine has been shown, but the eccentric shaft of the present invention can also be applied to four or more cylinders.

(D) In this embodiment, the eccentric shaft is divided into the first eccentric shaft and the second eccentric shaft, but in the case of a multi-cylinder rotary piston engine having four or more cylinders, two eccentric parts are provided on the second eccentric shaft. Alternatively, two second eccentric shafts may be provided, and a plurality of the second eccentric shafts may be supported by the small diameter portion of the first eccentric shaft.

(Effects of the Invention) Since the present invention is configured as described above, it has the following effects.

(A) The first eccentric shaft and the second eccentric shaft are press-fitted into the second eccentric shaft that uses taper fitting and the outer end of the second eccentric shaft that does not use taper fitting. Since the second eccentric shaft is firmly supported with respect to the first eccentric shaft, it is possible to prevent rattling between the first eccentric shaft and the second eccentric shaft due to engine vibration. .

(B) Since the first eccentric shaft and the second eccentric shaft are connected to each other by press-fitting, the shaft of the first eccentric shaft is different from that of the structure in which the end portions of the eccentric shaft are joined together. The center and the axis of the second eccentric shaft can be easily matched.

[Brief description of drawings]

FIG. 1 is a sectional view showing the overall configuration of a multi-cylinder rotary piston engine according to the present invention. FIG. 2 is an internal configuration diagram of a multi-cylinder rotary piston engine according to the present invention. FIG. 3 is a side view of the second eccentric shaft of the multi-cylinder rotary piston engine according to the present invention. FIG. 4 is a side view showing a partial configuration of the first eccentric shaft of the multi-cylinder rotary piston engine according to the present invention. 1 ... Multi-cylinder rotary piston engine body 28 ... First eccentric shaft 29 ... Large diameter part 30 ... Small diameter part 31 ... Eccentric part 32 ... Eccentric part 49 ... Second eccentric shaft 51 ... Tapered part 53 ...... Eccentric part

Claims (1)

[Claims] 1. A large-diameter portion having an eccentric portion on the outer periphery and a small-diameter portion having a smaller diameter than the large-diameter portion, wherein the small-diameter portion and the large-diameter portion are provided between the small-diameter portion and the large-diameter portion. A first eccentric shaft formed with a tapered portion that expands in diameter as it extends toward the end, and a hollow shape that includes an eccentric portion on the outer periphery and is fitted to the outer periphery of the small diameter portion, and is formed on the inner end portion The tapered hole is fitted into the tapered portion, and the outer end portion located axially opposite to the inner end portion is pressed into the small diameter portion, and is pressed toward the large diameter portion. An eccentric shaft for a multi-cylinder rotary piston engine, comprising: