JPS6311543B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an improvement in a throttle dash pot for an internal combustion engine.

As a means of reducing harmful exhaust gases such as HC generated during deceleration in automobiles, dart pots are installed in the carburetor and throttle body to slow down the speed of the accelerator pedal, but the characteristics change due to wear particles. However, there was a problem with durability.

The purpose of this invention is to propose a dart pot that can overcome these difficulties.

The conventional darts pot is covered by U.S. Patent No. 3081847.
As seen in the above issue, the structure was such that abrasion particles on the spring contact surface, abrasion particles on the stopper part, abrasion powder on the collar, etc. entered the check valve and orifice part, so after long-term use, the abrasion particles could be reversed. This had the disadvantage that it changed the characteristics of the stop valve and orifice, causing defects such as the dart pot operating time being too early or too late.

The present invention proposes a dart pot that does not have these drawbacks, and will now be described based on embodiments shown in the drawings.

The diaphragm 10 is sandwiched between two shells 8 and caulked to the rod 1 fitted with a resin collar 19. This is called a diaphragm subassembly. The guide 6 is caulked to the lower cover 7, and this is called a lower cover subassembly. The check valve 18 is attached to the top cover 11. A plate 13 forming an orifice section is placed on a sheet 14, and the retainer 1
2 is press-fitted into the top cover 11 to be pressed and fixed. This is called a cover subassembly. The diaphragm subassembly is caulked by the cover subassembly and lower cover subassembly via the gasket nut 9. A holder 15 is placed on the holder 15 in this state, a filter 16 is placed on top of the holder 15, and a cap 17 is placed on top of the holder 15. Finally, insert spring 5,
It is held down with a stopper 3, fixed with an E-ring 2, and covered with a rubber boot 4. If a sudden upward load in the pushing direction is applied to the tip of rod 1, check valve 1
8 is closed, and the air inside the casing is removed from plate 1.
The rod 1 passes through a very narrow orifice 3, passes through a holder 15, a filter 16, and is discharged to the outside through the gap between the cap 17 and the upper cover 11, and stops at the position where the stopper 3 hits the lower end of the guide 6. Therefore, the upper part of the shell 8 will not hit the upper cover 11. Therefore, no abrasion powder is generated from the movable parts in the pressure chamber. The upward movement of the rod 1 and the diaphragm 10 is hindered by the compressive resistance of the air present in the casing, resulting in a so-called damping effect. When the load is removed from the rod 1, the rod is pushed back by the force of the spring 5, and the check valve 18 opens. At that time, air flows from the outside through the gap between the cap 17 and the upper cover 11, the filter 16, the holder 15, and the opening in the check valve 18, and enters the pressure chamber A inside the casing, and the rod 1 quickly moves. be returned. The parts that generate abrasion powder in the illustrated dart pot are the contact surface where the spring 5 contacts the guide 6 and the stopper (retainer) 3, the contact surface between the stopper 3 and the guide 6, the sliding part between the guide 6 and the collar 19, and the shell 8. The wear powder from these parts is isolated by the diaphragm 10 and does not enter the pressure chamber A, so the check valve 18 and the orifice of the plate 13 are does not change the properties of or,
By using a large filter above the check valve and orifice, it is possible to reliably prevent dust from entering from the outside, and to prevent clogging of the orifice and the check valve from getting caught. Further, since the stopper (retainer) and the spring are arranged outside the casing partitioned by the top cover 11, cap 17, and diaphragm 10, the top cover 11 can be made of resin, which is effective in reducing costs.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of an embodiment of the invention. 1... Rod, 3... Stoppa (retainer),
5...Spring, 6...Guide, 7...Lower cover, 10...Diaphragm, 11...Upper cover, 13...Plate constituting the orifice, 16...Filter, 17...Cap, 18
……non-return valve.

Claims (1)

[Claims] 1 The chamber surrounded by the upper cover and lower cover is divided into two by a diaphragm, forming an atmospheric chamber and a pressure chamber.The pressure chamber has an orifice restricted by the upper cover and a check valve that allows flow into the chamber. , and communicates with the atmosphere through a filter provided on the outside thereof, and a guide is provided on the lower cover side for guiding a rod attached to the diaphragm and protruding to the outside, and a spring is provided on the outside of the guide. One end of the spring is engaged, the other end of the spring is engaged with a stopper attached to the protrusion of the rod, and the abutment surface of the lower end of the guide abuts the abutment surface of the stopper, causing the rod to enter the pressure chamber. A darth pot characterized by having a structure that restricts.