JPS6081467A - Distributor attaching structure for engine - Google Patents

Abstract

PURPOSE:To minimize the rattle of a distributor attaching section and the shift of spark ignition, by providing such an arrangement that the center section of a piston pin is formed in the center section of a crank section, a hydraulic cylinder is attached to the boss of the pin, and a distributor is attached to a cam shaft. CONSTITUTION:An intake valve 5 and exhaust valves 6a, 6b are disposed in an intake-port 3 and first and second ports 4a, 4b of an exhaust port system 4, respectively. The cam surfaces 8a, 8b of an exhaust side cam shaft 8 are contoured such that the opening period of the second port 4b lasts, extending between the opening period of the first port 4a and the opening period of the first period of another cylinder having the next firing order number. A distributor 13 is coupled to the other end of the exhaust side cam shaft 8. With this arrangement variations in the rotational speed of the cam shaft may be made small, and the rattle of the distributor attaching section and the shift of spark advance may be made minimum.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power distribution device structure for an engine.

[Prior art]

In general, an engine power distributor distributes and supplies high voltage generated by an ignition coil to the spark plugs of each cylinder at predetermined ignition timings. Since it is necessary for this power distribution device to operate in synchronization with the rotation of the engine, there are conventional power distribution devices that are attached to the camshaft. Jitsukai Showa 5
There is one shown in Japanese Patent No. 6-120365.

By the way, in the conventional power distribution type 1 structure in which the power distribution device is attached to the camshaft as described above, the camshaft resists the spring force of the valve spring, causing rotational fluctuations in the camshaft. As a result, there is a risk that rattling may occur in the handle of the power distributor, or that the advance angle mechanism within the power distributor may become out of synchronization with the rotation of the engine, causing the ignition advance angle to deviate.

[Purpose of the invention]

In view of these problems, the present invention provides an engine power distributor mounting structure that can reduce the rotational fluctuation of the cup shaft and minimize the rattling of the power distributor mounting part and the deviation of the ignition advance angle. (JL Zen)

[Structure of the invention]

Therefore, in the present invention, either one of the intake and exhaust ports 1- is formed into two ports, a first port and a second port, and the second port is formed into two ports.
The opening timing of the boat is set to span the opening timing of the first boat and the opening timing of the first boat 1- of the next cylinder in the ignition order. The rotation fluctuation of the camshaft that opens and closes the second boat is made small, and a power distribution device can be installed on this camshaft.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an engine power distributor mounting structure according to an embodiment of the present invention. In the figure, ■ is an engine having four first to fourth cylinders 2a to 2d, each of the cylinders 2a to 2d.
An intake boat 3 and an exhaust boat 4 are formed at 2d, and the exhaust boat 4 consists of two boats, a first boat 4a and a second boat 4b. Further, an intake valve 5 is provided in the intake boat 1-3, and an intake valve 5 is provided in the first valve 5 of the exhaust boat 4. 2nd bow) 4a, 4
Exhaust valves 6a and 6b are respectively disposed at the exhaust valves 6a and 6b.

Further, the engine 1 is provided with an intake side camshaft 7 that opens and closes the intake boat 3 and an exhaust side camshaft 8 that opens and closes the exhaust boat 4. A pulley 9.8 is attached to one end of the camshaft 7.8 on the intake side and the exhaust side. IO is attached, and the pulleys 9 and 10 are connected to the crankshaft boot by a timing heald (not shown), so that the force shafts I-7 and 8 are rotationally driven by the output of the engine l. It looks like this. Also, tappets 11.12 are installed on the intake side and exhaust side camshafts 7.8.
The cam surface 3a of the exhaust side camshaft 8 is formed with cam surfaces 7a, 8a, 8b that press the intake and exhaust valves 5, 6a, 6b via the cam surfaces 7a, 12b.

8b is the opening of the second boat 4b] period is the opening of the J boat 4a.
and the first of the cylinders whose firing order is next to that cylinder.
It has a profile spanning the opening period of the boat 4a. Here, the firing order of the cylinders is 1st. Third. 4th. It is in the second order. Further, a power distributor 13 is connected to the other end of the exhaust side camshaft 8.

Next, the functions and effects will be explained using FIG. 2.

Here, Fig. 2 shows the opening/closing timing of the exhaust valves (ia, 5b), and in the figure, p, i j (i=1~4.3=1°2)
are the norm timings of the j-th boat of the i-th cylinder, respectively.

When the engine operates, the rotational force of the engine 1 is transmitted to the intake side and exhaust side camshafts 7.8, and the camshafts 7.8 rotate synchronously with the engine 1. Then, the intake and exhaust valves 5, 6a and 6b of each cylinder 2a to 2d are opened and closed by the camshaft 7.8, and the power distributor 13 is operated by the rotation of the exhaust side force shaft 1-8.

At that time, for example, the first cylinder of the first cylinder 2a. 2nd boat 4a,
The opening/closing timing of 4b is such that the opening period E12 of the second ball l- of the j-th cylinder is equal to the opening period E11 of the hydraulic power of the first cylinder and the third cylinder of the next ignition order. E31, so that the exhaust side camshaft 8 always presses at least one exhaust valve 5a, 5b. As a result, the drag force of the valve spring acting on the exhaust side camshaft 8 becomes almost uniform when viewed as a whole, and the rotational fluctuation of the cam shirt 1-8 is greatly reduced compared to the conventional one-piece structure. There is almost no risk of rattling in the mounting part of the electric appliance 13,
Also, the deviation in the ignition advance angle can be minimized.

In the second embodiment, the power distributor is attached to the exhaust side camshaft, but this power distributor may be attached to the intake side camshaft. Also number 1. The valve timing of the second boat may be set differently in four specific operating ranges instead of in all operating ranges, and may also be set differently depending on the operating state.

〔Effect of the invention〕

As described above, the arrangement of the engine according to the present invention? h E) According to the mounting structure, either the intake or exhaust bow 1 should be
．． The opening timing of the second boat is set to span the opening timing of the first boat and the opening timing of the first boat of the next cylinder in the ignition order. Second
The rotational fluctuations of the camshaft that opens and closes the boat are minimized, and the power distributor can be mounted on this camshaft, minimizing rattling at the power distributor mounting part and deviations in the ignition advance angle. There is an effect that can be done.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a power distributor mounting structure for an engine according to an embodiment of the present invention, and FIG. 2 is a diagram for explaining the effects of the mounting structure. ■...Engine, 3...Intake boat, 4...Exhaust boat, 4a, 4b...1st. 2nd boat, 5... Intake valve, 5a, 5b... Exhaust valve, 7... Intake side force mushaf I., 8... Exhaust side camshaft, 13... Power distributor. Patent applicant: Toyo Kogyo Co., Ltd. Representative Patent attorney: Ken Kouse −

Claims (1)

[Claims] (1) An intake boat 1- having an intake valve, an exhaust port having a antagonistic valve, an intake side camshaft that opens and closes the intake boat, and an exhaust side camshaft that opens and closes the exhaust port. In the engine, the force of the intake port or air loss port 1 is formed into two boats, a first port and a second port, and the opening period of the second port is the same as the opening period of the first port 1. 1st cylinder in firing order
A power distribution device for an engine, characterized in that the power distribution device is connected to a camshaft that opens and closes an intake or exhaust port formed in a boat and is set to span an opening period of a boat. Inquiry structure.