JP2656478B2 - Eccentric drive for rotating mass - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a drive formed by a first eccentric and acting on at least one point of a rotating mass and a second eccentric. Guide means acting at at least one further point radially outwardly from said at least one point of the rotating mass, and a bearing device provided at at least one of these points of action The bearing arrangement having an elastic bearing bed consisting of a rubber-elastic molded ring held between the bearing ring of the bearing arrangement and the bearing bore of the rotating mass. Eccentric drive for rotating mass bodies.

2. Description of the Related Art An eccentric driving device of this type is described in Japanese Patent Application Laid-Open No. 61-283780 filed by the present applicant. In this known eccentric drive, the drive, which is the first eccentric, is formed by a drive shaft and an eccentric pin, and the guide, which is the second eccentric radially outward, is a guide shaft. And an eccentric pin.
The drive unit, which is the first eccentric device, acts on the inner peripheral portion (action point) of the rotating mass body to cause the entire rotating mass body to perform a circular motion defined by the eccentric amount of the eccentric pin. In order to ensure this circular motion of the whole rotating mass body, the guide portion, which is the second eccentric device, acts on the outer peripheral portion (action point) of the rotating mass body to guide the circular motion of the whole rotating mass body. I do. The guide shaft of the guide portion is rotated synchronously with the drive shaft via a timing belt transmission mechanism. As is well known, such an eccentric drive is used to drive a positive displacement machine (compressor or pump) and includes a spiral working chamber formed by a rotating mass and a casing. The medium is sucked, compressed, and discharged while being continuously displaced in the circumferential direction. In known eccentric drives of this type, the elastic bearing bed, which is formed by an elastic forming ring having a non-linear spring characteristic in the radial direction, can be produced by accumulating manufacturing tolerances or in different ways. The thermal expansion serves to compensate for the stresses that occur between both points of action. In this known eccentric drive, in order to fix the bearing ring in the bearing hole of the rotating disk (rotating mass body) in the axial direction, a small axial direction is formed in the bearing ring and the annular groove of the bearing hole. It was inserted with play and the two parts were axially fixed to each other by an engaging action. The circumferential fixing was performed by engaging a special thick portion, for example, having a semicircular cross section provided on the forming ring, with a bearing hole and a recess formed on the bearing ring.

However, fixing the bearing ring to the rotating mass by an engaging action requires a special operation step. For example, an annular groove must be formed on the inner peripheral surface of the bearing hole and the outer peripheral surface of the bearing ring by expensive plunge grinding.
In addition, special axial grooves must be formed in both parts for circumferential fixing. Even if the bearing ring is axially fixed by means of a spring ring, expensive machining must also be performed. This is because, even in this case, at least one of the annular grooves must be plunge-ground.

In order to secure the bearing ring and the rotating mass without engagement, the forming ring is connected to the bearing ring by a load generated during operation due to friction generated between the forming ring and the bearing ring and the rotating mass. Attempts have already been made to insert and retain a radial prestress so as to prevent axial or circumferential relative movement with the rotating mass.

[Problem to be solved by the invention] A problem to be solved by the present invention is to make it possible to easily incorporate a forming ring without requiring expensive processing costs.

[Means for Solving the Problem] To solve this problem, the configuration of the present invention employs the first
A drive acting on at least one point of the rotating mass, formed by an eccentric device of the type described above, and at least one drive formed by a second eccentric device and spaced from said at least one point of the rotating mass. It has a guide acting at another point and a bearing device provided at at least one of these points of action, the bearing device comprising a bearing ring of the bearing device and a bearing bore of the rotating mass. A resilient bearing bed consisting of a rubber-elastic molding ring held between the molding rings, the frictional forces occurring between the molding ring and the bearing ring and the rotating mass during operation. A rotating mass of the type inserted and held in a radially prestressed manner to prevent axial or circumferential relative movement between the bearing ring and the rotating mass due to the resulting load; In the eccentric drive of the above, the forming ring is held in an annular chamber, which is connected to the inner peripheral surface of the bearing hole of the rotating mass body, the outer peripheral surface of the bearing ring and the rotating mass body near one side. The partition is separated by a lateral step provided and a lateral step provided on the bearing ring near the other side surface.

[Example] Hereinafter, the configuration of the present invention will be specifically described based on an example shown in the drawings.

In the drawings, a bearing device, generally designated by the reference numeral 1, has a drive shaft or guide shaft 2, which is a rotating mass formed by a rotating disk 4 of a positive displacement machine. It has an eccentric pin 3 for the body. Details of such positive displacement machines are described, for example, in DE-A 35 19 981 and in the drawings.

The rotating disk 4 is supported by a bearing 7 held in a cup-shaped bearing sleeve 8 via a bearing ring 5 mounted in a bearing bore 6 and an eccentric pin of the drive shaft or guide shaft 2. 3 is supported. Hole in bearing ring 5
The cup-shaped bearing sleeve 8 pushed into the
In the region of the closed bottom, there is a lubricant reservoir 9 for lubricating a bearing 7, for example, configured as a needle bearing. The seal 10 is arranged between the eccentric pin 3 and the bearing ring 5 on the open end side of the bearing sleeve 8 surrounding the eccentric pin 3.

Between the inner peripheral surface 16 of the rotating disk 4 and the outer peripheral surface 12 of the bearing ring 5, there is provided an annular chamber 21 having a rectangular cross section for accommodating a rubber elastic forming ring 20. In the embodiment shown, the molding ring 20 has a cross-section in the form of three circles joined by axially parallel webs. With such a cross-section, the forming ring 20 has a non-linear spring characteristic in the radial direction, so that as the radial spring deformation increases, the spring stiffness increases quadratically. . That is, while the three circles are initially compressed, a large amount of spring deformation occurs with a small force, but when the web is compressed, the spring stiffness increases with a steep slope. However, instead of the cross-section as shown, other cross-sections which give rise to a non-linear spring characteristic in the radial direction are also conceivable.

An annular chamber 21 having a rectangular cross section formed between the rotating disk 4 and the bearing ring 5 has a lateral stepped portion 18 provided on the rotating disk 4 near one side surface in the axial direction. / 19,
Near the other side, it is separated by a lateral step 14/15 provided on the bearing ring 5. In this way, the rotating disk 4 and the bearing ring 5 are each provided with one stepped portion.
Since only 18/19 or 14/15 are formed, the rotating disk 4
The processing of the bearing ring 5 can be performed in one step. In short, it is not necessary to plunge the annular groove. At the same time, the assembly of the bearing device 1 is facilitated. That is, a rubber elastic molding ring 20 having an inner diameter smaller than the diameter of the outer peripheral surface 12 of the bearing ring 5 is first fitted over the outer peripheral surface 12 of the bearing ring 5. In short, the forming ring 20 is fitted over the bearing ring 5 under radial prestressing, in which case the chamfer 13 formed on the side of the bearing ring 5 on the side opposite to the step 14/15 Covering of the molding ring 20 is facilitated. After the forming ring 20 has been fitted over the outer peripheral surface 12 until it touches the annular shoulder 15 of the bearing ring 5, the bearing ring 5 is rotated from the side of the rotating disk 4 opposite the step 18/19. Bearing hole 6 of disk 4
Is pushed into. On this side surface of the rotating disk 4, a chamfered portion 17 is formed on an inner peripheral surface 16 of the rotating disk 4, and the chamfered portion 17 is provided with a bearing ring 5 having a forming ring 20.
While compressing the forming ring 20 in the radial direction.
It is easy to push in until the molding ring 20 touches the.

When the assembly is performed in this manner, the bearing ring 5
The rubber-elastic molding ring 20 arranged between the rotary disk 4 and the rotary disk 4 is radially prestressed, this prestress being sufficiently large and based on the loads occurring during the operation of the positive displacement machine. The axial and circumferential relative movement between the bearing ring 5 and the rotating disk 4 is prevented by the frictional force between the forming ring 20 and the rotating disk 4 and the bearing ring 5. Thus, additional means for axially or circumferentially fixing the bearing ring 5 to the rotating disk 4 are no longer necessary.

[Effect of the Invention] As described above, in the configuration of the present invention, the forming ring 20 is held in the annular chamber 21, and the annular chamber 212 is formed on the inner periphery of the bearing hole 6 of the rotating disk 4 which is a rotating mass body. Surface 16, the outer peripheral surface 12 of the bearing ring 5, a lateral step 18/19 provided on the rotating disk 4 near the one side, and a bearing near the other side. Since it is made to be partitioned by the side steps 14/15 provided on the ring 5, the production becomes easy. This is because the lateral steps 18/19 and 14/15 make it unnecessary to form the annular groove by plunge grinding. Moreover, the assembly work is simplified. This is because the prestressed forming ring 20 no longer needs to be mounted in the annular groove beyond the side wall of the annular groove, and therefore there is no risk of damaging the forming ring 20.

[Brief description of the drawings]

The drawing is a longitudinal section in the region of one eccentric device of an eccentric bearing device of a rotating mass. 1 ... bearing device, 2 ... drive shaft or guide shaft, 3 ... eccentric pin, 4 ... rotating disk, 5 ... bearing ring, 6 ... bearing hole, 7 ...
Bearing, 8 ... Bearing sleeve, 9 ... Lubricant storage chamber, 10 ... Seal, 11 ... Hole, 12 ... Outer peripheral surface, 13 ... Chamfered part, 14/15 ...
… Stepped part, 15 …… Circular shoulder, 16 …… Inner peripheral surface, 17 …… Chamfered part, 18
/ 19 …… Step, 19 …… Circular shoulder, 20 …… Forming ring, 21 …… Circular chamber

Claims (1)

(57) [Claims] 1. A drive formed by a first eccentric and acting on at least one point of the rotating mass, and a drive formed by a second eccentric and from said at least one point of the rotating mass. It has radially outwardly spaced guides acting on at least one other point and a bearing device provided on at least one of these points of action, the bearing device comprising: A resilient bearing bed comprising a rubber-elastic forming ring held between the bearing ring of the device and the bearing bore of the rotating mass, said forming ring comprising a forming ring and a bearing ring or a rotating mass. Inserted under radial prestress such that the frictional forces created between the bearing ring and the rotating mass prevent the axial or circumferential relative movement between the bearing ring and the rotating mass due to the loads created during operation. In an eccentric drive for a rotating mass of the retained type, a forming ring (20) is held in an annular chamber (21), which is a bearing for the rotating mass (4). An inner peripheral surface (16) of the hole (6), an outer peripheral surface of the bearing ring (5), and a lateral step (18/19) provided on the rotating mass body (4) near one side surface. And an eccentric drive for the rotating mass, characterized by being separated by a lateral step (14/15) provided on the bearing ring (5) near the other side.