JPS6047892A - Scroll type pump - Google Patents

Abstract

PURPOSE:To absorb excessive force generated in steel balls by the thermal expansions thereof during operation by a method wherein a receiving plate is provided in a circular groove formed on the back surface and the plate of a movable scroll member while the receiving plate is deflected toward the side of a releasing space. CONSTITUTION:The plate 7, arranged at the back surface of a side plate 52 for the movable scroll member 5, is provided with four sets of first circular grooves 8 with equal intervals, a releasing hole 9 is bored at the center of the bottom surface of the circular groove 8 and first receiving plate of spring material is arranged on the bottom surface. The second circular groove 12 is provided on the back surface of the side plate 52 so as to oppose to the first circular groove 8, a circular recess 13 is formed on the bottom surface thereof as a release space and the second receiving plate 14 of spring material is arranged on the bottom surface. According to this method, the first and second receiving plates 10, 14 are deflected toward the sides of releasing spaces 9, 13 when the excessive force is applied to the steel balls 16 by the thermal expansion during operation, and the force applied on the steel balls 16 may be absorbed, whereby the abnormal abrasion, breakage or the like may be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a scroll type pump, such as an air pump such as a pump for a supercharger of an automobile engine;
Alternatively, it is effective when used as a vacuum pump.

In conventional scroll pumps, the thrust bearing, which also has the function of preventing rotation of the movable scroll member, has a circular groove provided on the back surface of the movable scroll member, and a portion facing the circular groove on the surface facing the back surface of the movable scroll member. It consists of a circular groove provided in the groove, and a steel ball accommodated in such a manner that it spans both of the two circular grooves. Normally, when a pump is operated, the temperature inside the pump rises due to the pumping work of the fluid, and the movable scroll member and the fixed scroll member thermally expand due to the heat. Therefore, the bearing of the movable scroll member is subjected to not only the force normally received from the pressure of the working fluid but also the force due to thermal expansion as described above. Therefore, in conventional bearings, all of these forces act on the steel balls, and there is a risk that the steel balls may become abnormally worn, seize, or break.

Therefore, in view of the above problems, the present invention aims to prevent the steel balls forming the bearings of the movable scroll member from suffering abnormal wear, seizure, breakage, etc. caused by excessive loads acting on the steel balls. do.

In order to achieve this object, in the present invention, a receiving plate made of a spring material is arranged on the bottom of at least one of the circular grooves provided on the back surface of the movable scroll member and the surface opposite to this back surface, and A cylindrical side plate was disposed on the circumferential surface of the groove, and an escape space was provided on the bottom surface.

Hereinafter, an embodiment in which the present invention is used as a pump for a supercharger of an automobile engine will be described.

As shown in FIG. 1, a shaft 1 is rotated from an automobile engine (not shown) via a pulley or the like.
has an eccentric portion 1a having an axis O' eccentric from its axis 0 by ρ, and is rotatably supported by a boss portion 3a of a front housing 3 via a bearing 2°2'. A ratio balance weight 1b is provided on the eccentric portion 1a to smooth the rotation of the shaft 1, and a boss portion 5a of a movable scroll member 5 is rotatably fitted through a bearing 4.

The movable scroll member 5 includes a movable scroll portion 51, a side plate 52 integrally constructed with the movable scroll portion 51, and a boss portion 5a provided at the center of the side plate 52. The movable scroll portion 51 has a spiral shape, and the fixed scroll member 6 is disposed so as to mesh with the spiral movable scroll portion 51. The fixed scroll member 6 also includes a spiral fixed scroll portion 61 and a side plate 62 integrally constructed with the fixed scroll portion 61, and has the function of a rear housing that forms the outer shape of the rear portion of the pump.

A plate 7 is disposed on the back side of the side plate 52 of the movable scroll member 5, and is sandwiched between the front housing 3 and the fixed scroll member 6 and fixed to each other by bolts (not shown).

An O-ring 20 is arranged between the fixed scroll member 6 and the plate 7. Figure 2 is a front view of plate 7;
Six bolt holes 7a for passing bolts are bored in its outer edge. Furthermore, four first circular grooves 8 are provided at equal intervals inwardly from the bolt 7a, and a relief hole 9 is bored through the plate 7 as a relief space in the center of the bottom surface of the first circular groove 8. It is set up. Since the diameter of this escape hole 9 is smaller than the diameter of the first circular groove 8, a first plate 10 made of a spring material is disposed on the portion that remains as the bottom surface, and the circumference of the first circular groove 8 is A cylindrical first side plate 11 is press-fitted into the portion.

A second circular groove 12 is also provided on the back surface of the side plate 52 of the movable scroll member 5 at a position opposite to the first circular groove 8 of the plate 7. A circular recess 13 is also formed on the bottom surface of the second circular groove 12 as an escape space, a second receiving plate 14 made of a spring material is disposed on the bottom surface, and a circumferential portion of the second circular groove 12 is provided with a second receiving plate 14 made of a spring material. A cylindrical second side plate 15 is press-fitted.

In this way, a steel ball 16 is disposed between the first circular groove 8 and the second circular groove 12 in which the first and second receiving plates 10, 14 and the first and second side plates 11.15 are disposed, respectively. This supports the force of the movable scroll member 5 in the leftward direction in FIG. 1 and prevents the movable scroll member 5 from rotating.

The front housing 3 is provided with a suction port 17 for sucking fluid into the pump chamber P formed by the movable scroll member 5 and the fixed scroll member 6. In the center is a discharge port 18 for discharging the fluid in the pump chamber P to the outside of the pump.
is formed. Further, a plate 21 is disposed between the plate 7 and the front housing 3, and a bellows frame 22 is disposed so as to straddle both the plate 21 and the plate 7. This bellow flamm 22 prevents the fluid in the pump chamber P from flowing out along the shaft 1.

Next, the operation of the device of this embodiment will be explained.

When the shaft 1 is driven by a prime mover (not shown), the movable scroll member 5 is pivotally supported by the eccentric portion 1a of the shaft 1.
performs a turning motion. When the movable scroll member 5 rotates, the pump chamber P formed by the movable scroll member 5 and the fixed scroll member 6 repeatedly increases and decreases in volume. When the volume of the pump chamber P increases, air that has passed through an air cleaner (not shown) is sucked into the pump chamber P through the suction port 17.
As the volume of the pump chamber P decreases as the movable scroll member 5 rotates, the sucked air is discharged from the discharge port 18 and supercharged into a combustion chamber of a vehicle engine (not shown).

Here, the pressure inside the pump chamber P and the movable scroll member 5
Due to self-straddling thermal expansion, the movable scroll member 5 receives a force in the left direction in FIG. 1, and this force is supported by the steel balls 16. If excessive force is applied to the steel ball 16 at this time,
The first and second receiving plates 10 and 14 made of spring material provide relief space 9
．． It bends toward the steel ball 3 side and absorbs the force applied to the steel ball 16. Therefore, even if excessive force is applied to the steel ball 16, it is absorbed, and the steel ball 16 will not be damaged or abnormally worn.

In this embodiment, the first circular groove 8. provided on the back surface of the movable scroll member 5 and the plate 7. Although the relief spaces 9 and 13 are provided on both bottom surfaces of the second circular groove 12, the relief space 9 may be provided only in the first circular groove 8 as shown in FIG.
Alternatively, as shown in FIG. 4, the escape space 13 may be provided only in the second circular groove 12. The other operations and effects of Configuration 1 are the same as those of the first embodiment.

As explained above, if the scroll type pump of the present invention is used, even if the movable scroll member thermally expands and excessive force is applied to the steel balls, the receiving plate provided in the circular groove will bend excessively toward the relief space. Since the steel ball absorbs such force, there is no risk of abnormal wear or seizure of the steel ball. Further, since the receiving plate and the side plate are constructed separately, the receiving plate can be freely bent without being subject to side plate restrictions.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, and FIG.
Figure 3 is a front view showing the plate of the device, and Figures 3 and 4 are longitudinal sectional views showing other embodiments of the present invention. DESCRIPTION OF SYMBOLS 1... Shaft, la... Eccentric part, 3... Front housing, 5... Movable scroll member, 6...
Fixed scroll member, 8... First circular groove, 9... Relief space, 10... First receiving plate, 11... First side plate, 1
2...Second circular groove, 13...Escape space, 14...
Second receiving plate, 15... Second side plate, 16... Steel ball, 17
...Intake port, 18...Discharge port. Representative Patent Attorney Takashi Okabe Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] a housing forming the outer shape of the pump; a shaft rotatably supported by the housing and having an eccentric portion;
A movable scroll member that is rotatably supported by the eccentric portion of the shaft and performs a revolution movement without rotation; and a movable scroll member that is fixed to the housing so as to mesh with the movable scroll member, and forms a pump chamber together with the movable scroll member. a fixed scroll member, a suction port for sucking fluid into the pump chamber, a discharge port for discharging the fluid in the pump chamber to the outside of the pump chamber, a back surface of the movable ring member, and a surface facing the back surface. a circular groove formed in the movable ring member, and a steel ball housed in the circular groove, and a bottom surface of at least one of the circular grooves formed in the back surface of the movable ring member and the surface facing the back surface. A scroll pump characterized in that a receiving plate made of a spring material is disposed, a cylindrical side plate is disposed on the circumferential surface of the circular groove, and a relief space is provided on the bottom surface of the circular groove. .