JPS6244123B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bellows-shaped double-acting actuator used for adjusting an air pump damper of an automobile air conditioner.

Conventionally, this type of device has two diaphragms housed in a metal frame with a spring interposed between them.
The tip of the piston that passes through two diaphragms is connected to the damper, and one diaphragm is deformed to cause the piston to move back to the first stage, and then the other diaphragm is deformed to move the piston to move back to the second stage to open the damper in two stages. However, it requires a large number of parts, such as a metal frame, diaphragm, piston, and spring, and it is time-consuming to assemble them airtight, and furthermore, dust gets in the sliding parts of the piston, resulting in malfunction. There were drawbacks such as being more reliable.

The present invention is intended to eliminate these drawbacks of the prior art.

Next, embodiments of the present invention will be described with reference to FIGS. 1 to 3 of the accompanying drawings.

Reference numeral 1 denotes an outer bellows body made of synthetic resin, in which a bellows 1a and an end plate 2 are integrally formed by blow molding a soft thermoplastic synthetic resin such as thermoplastic polyester elastomer. A mounting piece 3 for attaching a tow cable is integrally protruded from the center portion of the outer surface of the end plate 2, which is formed in a gradually increasing thickness, and a first stopper 4 made of hard synthetic resin is provided at the center of the inner surface of the end plate 2. is protruded by insert molding. Further, a bellows 1a is integrally formed to protrude from the peripheral edge of the end plate 2, which is formed to be gradually thinner, and the opening edge 5 of the bellows 1a is fitted and fixed in the annular groove 7a of the fixed plate 6, and is sealed. The fixing plate 6 is made of a hard synthetic resin plate or a metal plate. Next, 8 is an inner bellows body, and the bellows 8a and the end plate 10 are integrally formed by blow molding the same soft thermoplastic synthetic resin as the outer bellows body.
A second stopper 11 is accommodated in the outer bellows body 1 through a ventilation gap 9 and protrudes from the end plate 1 opposite to the first stopper 4 of the outer bellows body 1, and the opening edge 12 of the bellows 8a is connected to the fixing plate 6. It is fitted and fixed in the annular groove 7b and hermetically sealed.

Furthermore, a guide shaft 13 which becomes a third stopper is insert-molded into the second stopper 11 of the end plate 10 and is provided to protrude toward the fixed plate 6, and a protrusion 15 provided at the inner end of the guide shaft 13 which becomes the third stopper. When the inner bellows body 8 comes into contact with the fixed plate 6, the contraction of the inner bellows body 8 is stopped. Also, the guide shaft 1 serves as the third stopper.
3 is inserted into the hollow guide tube 14 that protrudes inward from the fixed plate 9 so as to be able to move forward and backward, and when the protrusion 15 at the tip is engaged with the engaging portion 17 provided at the inner end of the guide tube 14. The inner bellows body 8 stops expanding. A ventilation groove 16 opens in the axial direction from the inner end of the guide tube 14 . Further, on the fixed plate 6, a ventilation section 18 consisting of a ventilation pipe communicating with the ventilation gap 9 in the outer bellows body 1 and a ventilation section 19 consisting of a ventilation pipe communicating with the inner bellows body 8 are provided to protrude outward. do.
Further, a mounting piece 20 is provided protruding outward from the center of the fixing plate 6, and several reinforcing pieces 21 and 22 are provided radially protruding from the end plate 2 of the outer bellows body 1 and the fixing plate 6, respectively.

Further, when the inside of the outer bellows body 1 is made negative pressure through the ventilation part 18, the protrusion 15 is locked by the engaging part 17, and while the inner bellows body 8 is prevented from expanding, only the outer bellows body 1 is contracted. As a result, the first stopper 4 comes into contact with the second stopper 11. Furthermore, when the inside of the inner bellows body 8 is made negative pressure through the ventilation part 19, the inner bellows body 8 contracts and the outer bellows body 1 further contracts, so that the protrusion 15 comes into contact with the fixing plate 6. There is.

When manufacturing, please use synthetic resin or metal first
The outer bellows body 1 is blow-molded with the stopper 4 inserted, and the inner bellows body 8 is formed by inserting the second stopper 11 and the guide shaft 13, which are integrally formed of hard synthetic resin or metal, and serve as the third stopper. Blow molding is performed, and the opening edge 12 of the inner bellows body 8 is adhesively fixed to the fixing plate 6, and then the opening edge 5 of the outer bellows body 1 is adhesively fixed to the fixing plate 6.

Next, the operation of this embodiment will be explained.

As shown in FIG. 4, the mounting piece 3 of the end plate 2 of the outer bellows body 1 is connected by a tow cable 25 to a damper 24 which is pivoted at one end facing the air passage 23 of an air conditioner of an automobile or the like. 24 is pulled by a tension spring 26 in a direction opposite to the direction in which the tow rope 25 is pulled. The other end of the outer bellows body 1 is pivoted to a fixed body 27 by a mounting piece 20 of this fixed plate 6.

In such a state, first the inner bellows body 8
The ventilation part 19 is opened to atmospheric pressure through, for example, a three-way switching valve, and when the ventilation part 18 is communicated with a negative pressure source through, for example, a three-way switching valve to apply negative pressure to the outer bellows body 1, the inner The extension of the bellows body 8 is caused by the guide shaft 1
The protrusion 15 of the guide tube 14 is engaged with the engaging portion 17 of the guide tube 14 and stopped, and the outer bellows body 1 contracts.
The damper 24 rotates clockwise from position a. When the first stopper 4 of the outer bellows body 1 comes into contact with the second stopper 11 of the inner bellows body 8, the contraction of the outer bellows body 1 is stopped for the following reason. At this time, the damper 24 is at position b.
That is, when the stoppers 4 and 11 come into contact with each other,
Of the pressure receiving area of the outer bellows body 1, the inner bellows body 8
The pressure-receiving areas of are canceled out by pushing each other, and the actual pressure-receiving effective area of the outer bellows body 1 is only the annular part of the ventilation gap 9 between the inner and outer bellows, and the contraction due to the negative pressure acting only on that annular part Since the spring is predesigned so that the force is smaller than the tension force of the tension spring 26, the contraction of the outer bellows body 1 stops at that position. Therefore, the damper 24 is reliably stopped once at position b (this is considered as the first operation).

Next, while continuing to apply negative pressure inside the outer bellows body 1, the ventilation section 19 is connected to a negative pressure source by switching the three-way switching valve, etc., and negative pressure is also applied to the inner bellows body 8, so that the inner bellows body 8 contracts. Along with this, the outer bellows body 1 also shrinks, and the shrinkage progresses until the protrusion 15 of the guide shaft 13, which serves as the third stopper of the inner bellows body 8, comes into contact with the inner surface of the fixed plate 6, and the damper 24 is at position c. It stops when it reaches (this is called the second operation). When the damper 24 is returned to the a position, the ventilation portions 18 and 19 are communicated with atmospheric pressure by switching the three-way switching valve or the like.

According to the present invention, the inner and outer synthetic resin bellows bodies are both formed integrally with the end plate and the bellows, so they are easy to manufacture and can be molded all at once by blow molding of synthetic resin, etc. Not only can the trouble of attaching the bellows to the end plate be saved, but there is also no need to use an airtight member to maintain the airtightness of the connecting portion between the two. Moreover, since the end plate is made gradually thicker at the center and gradually thinner at the periphery to form a bellows, the end plate does not deform when the bellows body expands and contracts, and it can be attached to the end plate. It is convenient for forming pieces and attaching guide shafts.

Further, the inner bellows body is housed in the outer bellows body, the open ends of both bellows are closely fixed to a fixing plate, the end plates of the outer and inner bellows bodies are movable toward and away from each other, and the outer and inner bellows are attached to the fixing plate. A ventilation portion communicating with the inside of the body is formed, and a guide shaft having a protrusion protruding from the end plate of the inner bellows body can be moved back and forth in a guide tube protruding from the fixed plate and having an engaging portion. When the outer bellows body is inserted into the outer bellows body and a negative pressure is created inside the outer bellows body, the protrusion is engaged with the engagement portion and only the outer bellows body contracts while preventing the inner bellows body from elongating. When the inner bellows body is activated and a negative pressure is created inside the inner bellows body, the inner bellows body contracts and the outer bellows body is further contracted to perform a second operation. Despite its simple structure, which does not use a rigid case body for support or pistons, springs, sealing members, etc., the two-stage operation of the end plate of the outer bellows body is extremely smooth and reliable. It will be held in Furthermore, since the number of parts is small, assembly is extremely easy.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of the device showing an example of the embodiment of the present invention, FIG. 2 is a front view of the same, FIG. 3 is a back view of the same, and FIG. 4 is an explanatory view showing the same in use. 1... Outer bellows body, 1a... Bellows, 2...
... end plate, 6 ... fixed plate, 8 ... inner bellows body,
8a... Bellows, 10... End plate, 13... Guide shaft, 14... Guide tube, 15... Protrusion, 17...
Engagement part, 18, 19... Ventilation part.

Claims (1)

[Claims] 1. A synthetic resin in which the end plate and the bellows are integrally formed in the same way within an outer bellows body made of synthetic resin, in which the bellows are integrally formed from the peripheral edge, which is formed gradually thinner, of the end plate, which is formed gradually thicker in the center. An inner bellows body made of resin is housed, the opening ends of the bellows of the outer and inner bellows bodies are closely fixed to a fixing plate, the end plates of the outer and inner bellows bodies are movable toward and away from each other, and the fixing plate A ventilation portion communicating with the inside of the outer bellows body and the inside of the inner bellows body, respectively, are formed in the guide cylinder, which is provided to protrude from the fixed plate in the axial direction and has an engaging portion, and is provided to protrude from the end face plate of the inner bellows body. When a guide shaft having a section is inserted so as to be freely retractable and a negative pressure is applied to the inside of the outer bellows body through the ventilation section,
The protrusion is locked to the engaging portion to prevent the inner bellows from elongating, while only the outer bellows contracts to perform the first operation, and the interior of the inner bellows is moved through the ventilation portion. 1. A bellows-like double-acting actuator, characterized in that when a negative pressure is applied to the inner bellows body, the inner bellows body contracts and the outer bellows body further contracts to perform a second operation.