JPS6055282B2 - Method for manufacturing air cleaner cover seal packing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a seal packing for an air cleaner cover used for an internal combustion engine.

The air cleaner to which the present invention is directed has a structure in which a filter element is disposed within a housing formed of a cylindrical body and a dish-shaped cover, and an annular seal packing is installed between the body and the cover. As shown in Japanese Utility Model Publication No. 51-15855, this annular seal packing is made by moving a foamable resin, such as a polyurethane foam raw material, into an annular groove formed on the outer periphery of a dish-shaped cover over the annular groove.
It is discharged from a nozzle that rotates once or from a nozzle placed on the annular groove of the rotating cover, and is foamed to form on the outer periphery of the cover. In this method, for example, resin discharged into the annular groove of the cover from a nozzle that rotates once on the annular groove overlaps at its discharge start point and discharge end point, causing height irregularities, as shown in Figure 1. This has the drawback that the sealing properties of the sealing packing are impaired as the sealing properties of the sealing packing are impaired.

Note that if the resin to be discharged has a low viscosity and a slow reaction, if the resin is left to stand for a certain period of time after discharge, the liquid level will flatten and this problem will not occur. will get worse. In order to increase mass productivity, it is necessary to use a foamable resin with high viscosity and high reactivity, so the above drawbacks will remain in this case. Therefore, the present invention provides a method for manufacturing an annular seal packing formed by discharging resin from a nozzle, in which the discharge amount is continuously increased at the start of discharging the foamable resin mixture, and then the discharge amount is maintained at a predetermined constant amount. The foamable resin mixture is discharged to a uniform height by continuously decreasing the discharge amount at the end of the discharge and setting the sum of the discharge amount at the beginning of the discharge and the discharge amount at the end of the discharge to the above-mentioned constant amount. To provide a method for manufacturing an air cleaner cover seal packing that does not reduce sealing performance.

To explain by way of an example, first, in FIG. 2, 5 and 1 are a forming device used in the seal packing manufacturing method according to the present invention, 2 is a dish-shaped cover of an air cleaner having an annular groove 4 on the outer periphery, and 3 is a forming device used in the seal packing manufacturing method according to the present invention. is a rotating table for rotating the cover.

The forming device 1 has tanks 5 and 6 containing foamed resin raw materials A and B, which are connected to a discharge control device 13 by conduits 9, 10, 11, and 12 via pumps 7 and 8, respectively. There is. At the same time, the discharge control device 13 has a conduit 1
4 connects the solvent tank 33. Discharge control device 1
3 has the function of sufficiently mixing the raw materials A and B in the tank, and also controlling the mixture in a predetermined amount and appropriately, as will be described later. The dish-shaped cover 2 has an annular groove 4 on its outer periphery, in which raw materials are mixed and discharged to form a seal packing.

Further, the rotary table 3 has a rotation drive unit 34 such as a motor,
This is for rotating the cover placed thereon. The discharge control device 13 and the rotary table 3 are controlled by an operation control device (not shown) to cause the plungers 31 and 32 of the device 13 to move up and down for one cycle while the cover rotates approximately once. The foaming resin mixture is controlled to be supplied from the nozzle 40 to one location in the annular groove 4 of the foamable resin mixture liquid powder 2 over approximately 3600 mm.

Next, the structure of the discharge device 13 will be explained.

In FIGS. 3, 4, and 5, 15 is a body, which has a central hole 16 passing through the center of the body, and a first annular chamber 17 and a first annular chamber 17 connected thereto around the central hole 16. , second annular chambers 18, 19 of smaller diameter are provided. Further, on the outer periphery of the body 15, there are air flow ports 260, 21 communicating with the annular chamber 17, and raw material flow ports 22, 23, 24, 25 communicating with the annular chambers 18, 19, respectively,
There are also flow passages 26 and 27 at the bottom that communicate with the annular chambers 18 and 19.
There is. Inside the core hole 16 is a port with an impeller 28 fixed to one end and a pulley 30 fixed to the other end! A tube 29 is inserted.
Pulley 30 is connected to a drive source via a belt (not shown). Inside the second annular chambers 18 and 19, a plunger 3 is provided.
1 and 32 are slidably arranged. Plungia 31
, 32 are each of the same shape, with a lower end forming a valve 1 and an upper end connected to a disk 35 inserted into the first annular chamber 17. Moreover, the middle part of the plunger forms a notch part 36 cut along the circumference, and creates a space between it and the second annular indoor wall, which forms a flow path. Raw material communication port 23
, 25 is an inverted truncated conical valve body, and its outer periphery and the second annular interior wall form a sealed space 37 having a triangular cross-section. When the lower end of the plunger is installed at the bottom of the second annular chamber of the body 15, there is no communication between the raw material flow port 23 and the flow path 16, and between the raw material flow port 25 and the flow path 27. The disk 35 is arranged within the first annular chamber 17 and slides up and down (between the air flow openings 20, 21). A lid 38 is attached to the upper part of the body 15 configured as described above, and an impeller housing 39 is fixed to the lower part.At the same time, a nozzle 40 is attached to the tip of the housing 39 for discharge and control. A device 13 is formed.

The discharge control device 13 connects the raw material flow ports 22 and 23 with conduits 9,
10, conduit pipes 11 and 12 are connected to the raw material distribution ports 24 and 25, respectively, and compressed air supply pipes 41 and 42 are connected to the air distribution ports 20 and 21 for use. The supply pipes 41 and 42 have flow rate control valves 43 and 44.
and a compressed air supply (not shown) via a solenoid valve 45
leading to.

The solenoid valve 45 is controlled by a timer 46 to reverse the air flow path. The method for manufacturing a seal packing for an air cleaner cover using a two-component foamed polyurethane resin is as follows.

When the pump 7 is started, the liquid raw material A, which is a raw material component of the polyurethane resin, flows from the tank 5 through the conduit 9 to the raw material distribution port 23 of the discharge control device 13, and from there flows through the notch 36 of the plunger 31 and the It circulates into the tank 5 from the flow port 22 through a flow path formed between the two annular interior walls. Similarly, raw material B is also circulated through the pump 8 upon startup. When the solenoid valve 45 is operated to cause compressed air to flow from the compressed air supply source through the conduit 42 and into the air flow port 21, fluid pressure acts on the lower surface of the disk 35 disposed in the first annular chamber 17 and raises it. At the same time, the plungers 31 and 32 connected to the disk 35 are also raised. Along with this, the lower end of the plunger, which was in contact with the bottom of the second annular chamber,
Leaving the bottom part, the raw material distribution port 23 and the flow path 26, and the raw material distribution port 25 and the flow path 27 are communicated with each other, and the raw materials A and B are connected to each other.
is sent into the housing 39. When a predetermined period of time has elapsed, the timer 46 or the solenoid valve 45 is operated to reverse the flow of compressed air. As a result, compressed air flows in from the air flow opening 20 and acts on the upper surface of the disk 35, thereby causing the plunger 3 connected thereto to act on the upper surface of the disk 35.
1 and 32 are lowered to close the flow passages 26 and 27, and the supply of raw materials A and B into the housing 39 is stopped. The raw materials A and B in the housing 39 are transported by the rotating impeller 2.
8 to form a foamable resin mixture, and the mixture is thoroughly mixed by the nozzle 40 to the annular groove 4 provided in the air cleaner cover 2.
discharged inside. The air cleaner cover 2 is arranged horizontally on the rotary table 3, and the air cleaner cover 2 is arranged horizontally on the rotary table 3, and the air cleaner cover 2 is arranged horizontally on the rotary table 3.
Rotate to 0 position. As shown in FIG. 6, as the plunger 32 rises and its lower end exceeds point a, the opening cross-sectional area increases continuously, and the amount of discharge of the mixed liquid increases accordingly, so that the lower end position of the plunger 32 reaches c Once the point is exceeded, it becomes a constant amount.

Conversely, as the plunger 32 descends, the opening cross-sectional area becomes
The discharge amount decreases continuously, and the flow path is completely blocked when the plunger 32 comes into contact with the bottom. Further, when the lower end of the plunger 32 is between positions a and b, a part of the raw material is bypassed and returned into the tank, and the amount sent into the housing 39 is
It will increase or decrease according to the rise or fall of . As a result, from the start of discharging the foamable resin mixture, that is, from when the lower end of the rising plunger 32 is located at point a in FIG. 6 until it reaches point b, the discharge amount increases continuously. However, after c, the amount is constant, and from the end of the discharge, that is, when the lower end of the descending plunger 32 is located at c, until it reaches after a, the discharge amount decreases continuously. Become. Therefore, the amount of the foamable resin mixture to be discharged at the start and end of the discharge is approximately equal to the amount to be discharged when the lower end of the plunger 32 is above c, The height becomes uniform (Figure 7). Therefore, Plungia 31,
32 during one cycle (ascent and descent), the rotating table 3
will be rotated by approximately 360 degrees or slightly more than 360 degrees. This value is optimally determined depending on the discharge speed or the rotational speed of the rotary table 3. If the foamable resin mixture in the annular groove 4 of the air cleaner cover is left as it is, it will foam due to a chemical reaction and form a highly elastic seal packing.

Then, if necessary, heat the seal packing to cure it. As described above, in the process of discharging the foamable resin mixture from the nozzle into the annular groove of the cover, the discharge amount is continuously increased and decreased at the start and end of the discharge, and the discharge amount at the beginning of the discharge is Since the sum of the sum of the discharge amount and the discharge amount at the end of discharge is the same value as the discharge amount discharged between the start of discharge and the end of discharge, foaming is achieved in the entire area within the annular groove of the cover. To provide an air cleaner cover seal packing with a resin mixture having a uniform height and excellent sealing properties.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of a seal packing formed by a conventional manufacturing method, FIG. 2 is a diagram of an apparatus for explaining the manufacturing method of the present invention, and FIG. 3 is a cross-sectional view of a discharge control device used in the manufacturing method of the present invention. Figures 4 and 5 are C-C in Figure 3.
6 is a partially enlarged view of FIG. 3, and FIG. 7 is a partially sectional view of the seal packing obtained according to the present invention. 13... Discharge control device, 22, 23, 24, 2
5... Raw material distribution port, 15... Body,
26, 27... Distribution path, 17... First
Annular chamber, 31, 32... Plunger, 18, 1
9...Second annular chamber, 355...Disk, 20, 21...Air circulation port, 38...
...Lid body.

Claims (1)

[Claims] 1. A method for manufacturing an air cleaner cover seal packing, in which a foamable resin mixture is sequentially discharged from one location in the annular groove of a dish-shaped cover provided with an annular groove on the outer periphery, and the mixture is foamed to form an elastic seal packing, The discharge amount of the foamable resin mixture is continuously increased at the beginning of dispensing, then maintained at a predetermined constant amount, and the discharge amount is continuously decreased at the end of dispensing, so that the dispensing amount at the beginning of dispensing and the dispensing amount at the end of dispensing are changed. A method for manufacturing an air cleaner cover seal packing, characterized by a discharge step in which the sum of the above is set to the fixed amount.