Starting control valve assembly for multiple throttle

Abstract: In a starting control valve assembly, bypass tubes connecting intake ports of each throttle body are connected to joint pipes 16 of a starting control valve assembly 11. The starting control valve assembly 11 comprises valve bodies 12, communication paths 13 formed inside the valve bodies 12 and communicating with an air cleaner, first flow paths 17 and second flow paths 24 connecting the communication paths 13 and the joint pipes 16, tuning screws 21 for respectively adjusting opening amounts of each of the first flow paths 17, and a shaft valve 26 for collectively adjusting opening amounts of the second flow paths 24. Through holes are formed orthogonal to the second flow paths 24. The shaft valve 26 is rotatably provided inside the through holes 25. A plurality of communication holes 27 for respectively connecting the second flow paths 24 are formed in the shaft valve 26, all facing in the same direction. This is to simplify idle opening amount between each cylinder and simplify the structure of a throttle body.

Description: This invention relates to a starting control valve assembly for a multiple throttle of a multiple cylinder engine of a vehicle such as a motorcycle. In a multiple throttle valve body of a multiple cylinder engine of a motorcycle, etc., as shown in Fig. 6 and Fig. 7, a starter valve 3 is provided for each throttle body 1, and the inside of an air cleaner 4 is connected through these starter valves 3 to intake ports 5 of throttle bodies 1. The starter valve 3 is formed in the throttle body 1, and has tuning screws 3a, 3b provided midway along a flow path connected to the intake port 5. Valves provided on the tips of the tuning screws 3a are moved by rotating tuning screws 3a other than tuning screw 3b that constitutes a reference among the tuning screws 3a, 3b, and adjustment of the degree of idle opening between each cylinder is carried out by adjusting the degree of opening of the flow paths, and adjusting the amount of intake from the air cleaner 4. Further, these starter valves 3 are provided with lever plates 6 respectively engaged with the tuning screws 3a, 3b, and these lever plates 6 are attached to a support shaft 7 which is supported rotatably and in a condition of being urged by a spring 8. A wire drawn from a choke is connected to one of these lever plates 6 and at the time of starting the engine the lever plate 6 is rotated backwards against the force of the spring 8, with the axis of the support shaft 7 as a center, by pulling of the wire, and in this way each of the tuning screws 3a, 3b of each of the starter valves 3 are collectively rotated towards the rear, and the intake amount of the intake ports 5 is increased. When the intake amount is increased at start up, the above described starter valves 3 are simultaneously rotated towards the rear, which means there is a need for a connecting structure in which the tuning screws of each of the starter valves 3 can slide together, which increases the number of components and brings about an increase in the cost. Also, there is a simple structure for distributing air from one valve to the intake ports of each throttle body at the time of idling and start up, but in this case, competition for air supply occurs between cylinders which causes a usage limitation and a uniform air amount can not be supplied. This invention has been conceived in view of the above described situation, and an object of this invention is to provide a starting control valve assembly for a multiple throttle capable of bringing about simplification in the structure of a throttle body 1 and associated cost reduction, and in which adjustment of the extent of idle opening between cylinders of each throttle body is easy. In order to achieve the above described object, a starting control valve assembly for a multiple throttle according to claim 1 is for a multiple throttle with multiple throttle bodies having intake ports for introducing a mixture to each combustion chamber of a multiple cylinder engine, for supplying air from an air cleaner to said intake paths via a bypass channel, and comprises valve bodies having supply paths with one end connected to each throttle body and respective other ends connected to the intake ports; connection paths, formed in the valve bodies, connected to the air cleaner; first flow paths and second flow paths for connecting the connection paths and the supply paths; adjustment screws, respectively provided in the first flow paths, for adjusting respective open amounts of the first flow paths; and rod like shaft valves rotatably provided within through holes crossing respective second flow paths, wherein a plurality of idle connection holes respectively connected to the second flow paths are formed in the shaft valves, facing in the same direction, and opening extents of the second flow paths are adjusted together using the idle connection holes, by causing the shaft valves to rotate. According to the starting control valve assembly for a multiple throttle as disclosed in claim 1, the structure is such that it allows the idle adjustment for each throttle and variation of intake at the time of starting to be carried out collectively using a single shaft valve, which means that compared to the structure of the related art, where a starter valve is provided for each cylinder and in order to cause each of the adjustment screws of these starter valves to move collectively it is necessary to have a structure connecting the adjustment screws together, it is possible to simplify the structure of the valve itself, and there is no need for a connecting structure, which brings about a substantial reduction in the number of component parts and a drastic reduction in cost. Also, since there is no competition for air supply between the cylinders when idling and starting air is supplied to the intake ports of each of the throttle bodies through the respective second flow paths, it is possible to ensure stable idling. Also, idle adjustment and increase in intake amount at the time of starting for each throttle can be carried out collectively by one shaft valve provided in a valve body. A starting control valve assembly for a multiple throttle according to claim 2 is basically the starting control valve assembly for a multiple throttle as disclosed in claim 1, wherein seal members are provided in the shaft valves at positions interposed between the second flow paths, and each second flow path is made airtight. According to the starting control valve assembly for a multiple throttle as disclosed in claim 2, since seal members are provided on both ends of the shaft valve sandwiching the second flow paths, it is possible to prevent these second flow paths leaking. In this way, it is possible to prevent leaks between each second flow path. A starting control valve assembly for a multiple throttle according to claim 3 is basically the starting control valve assembly for a multiple throttle as disclosed in claim 1 or claim 2, wherein control motors are provided in the shaft valves, and the shaft valves are rotatably adjusted using the control motors. According to the starting control valve assembly for a multiple throttle as disclosed in claim 3, it is very easy to electrically control the engine idle opening amount and variation in intake when starting, using a control motor connected to the end of the shaft valve. In this way, the engine idle opening amount and increase in air intake amount at the time of start up can be electrically controlled extremely easily by the control motors. A starting control valve assembly for a multiple throttle according to claim 4 is basically the starting control valve assembly for a multiple throttle as disclosed in claim 1 or claim 2, wherein rods of a displacement device causing movement of the rods in response temperature variations are connected to the shaft valves, and the shaft valves are adjusted by the displacement device. According to the starting control valve assembly for a multiple throttle as disclosed in claim 4, since a rod of a displacement device for moving the rod in response to temperature variation is connected to the end of the shaft valve through a link, for example, making the displacement device operate using variation in temperature of engine coolant, the shaft valve is made to rotate in response to variations in engine temperature, and it is possible to vary idling amount and intake when starting. In this way, by having the displacement device operate, for example, due to variations in temperature of coolant, the shaft valves are rotated according to variations in engine temperature and it is possible to increase the idle opening amount and amount of intake at the time of starting. Embodiments of a starting control valve assembly for a multiple throttle of the present invention will now be described below with reference to the drawings. Fig. 1 is a cross sectional view of a starting control valve assembly for describing the composition and structure of a starting control valve assembly for a multiple throttle of an embodiment of the present invention; Fig. 2 is a cross sectional drawing taken along line A - A in Fig. 1 of a starting control valve assembly for describing the composition and structure of a starting control valve assembly for a multiple throttle of an embodiment of the present invention, Fig. 3 is a side view of a starting control valve assembly for describing the composition and structure of a starting control valve assembly for a multiple throttle of an embodiment of the present invention, Fig. 4 is a cross sectional view along line A - A in Fig. 1 for describing the composition and structure of a starting control valve assembly for a multiple throttle of another embodiment of the present invention; Fig. 5 is a cross sectional view along line A - A in Fig. 1 for describing the composition and structure of a starting control valve assembly for a multiple throttle of another embodiment of the present invention, Fig. 6 is a perspective drawing of a throttle body of the related art provided with starter valves; and Fig. 7 is a rear view of a starter valve for describing the composition and structure of the starter valves provided in the throttle body. In Fig. 1 to Fig. 3, reference numeral 11 is a starting control valve assembly provided in a multiple throttle body of a motorcycle, etc., and bypass tubes 10, connected to each throttle body constituting the multiple throttle body and communicating with the intake ports of the throttle bodies, are connected to this starting control valve assembly 11. Communication paths 13 are formed in the valve bodies 12 constituting the starting control valve assembly 11, along the width direction. Air introduction ports 14 are provided above the valve bodies 12, pipes (not shown) connected to the air cleaner are connected to these introduction ports 14, and air is supplied to the communication paths 13 through these introduction ports 14. Joint pipes 16 respectively connected to the bypass tubes 10 are also provided in the valve bodies 12, and the inside of these joint pipes 16 and the communication paths 13 are connected together through first flow paths 17, formed for each cylinder, and second flow paths 24. Namely, these joint pipes 16 are supply paths for supplying air to each throttle body. Tuning screws 21 are provided midway along the first flow paths 17. These tuning screws 21 are screwed into screw holes 22 formed in the valve bodies 12. Tip parts 21a of these tuning screws 21 are also inserted into holes 23 crossing the flow paths 17, and in this way the extent to which the screws are screwed in when the tuning screws 21 are rotated is made to fluctuate. The opening amounts of the first flow paths 17 are adjusted by thus causing the extent to which tip parts 21a are inserted into the holes 23 to fluctuate. That is, the amount of intake air supplied from the air cleaner to the intake port of each throttle body through the valve bodies 12 and the bypass tubes 10 is adjusted by rotating the tuning screws 21. Further, through holes 25 are formed in the valve bodies 12, crossing the second flow paths 24 and communicating with these second flow paths 24. A rod like shaft valve 26 is rotatably provided in the through hole 25. Idle communication holes 27, being the same in number as the number of cylinders, are formed in the shaft valves 26, in the same direction and orthogonal to the shaft. Seal members 28 are also provided on both sides of the shaft valve 26 sandwiching the second flow paths 24, and each of the second flow paths 24 are made airtight. Then , by rotating the shaft valve 26 and establishing paths between the communication holes 27 formed in the shaft valve 26 and the second flow paths 24, a path is set up between the communication paths 13 connecting to the air cleaner and the joint pipes 16 connecting to the intake ports of the throttle bodies through the bypass tubes 10. Air is thus supplied from the air cleaner to the intake ports of each throttle body through the valve bodies 12 and the bypass tubes 10. A lever 29 is also provided on the shaft valve 26 on the end. A wire attachment portion 29a is formed on the end of this lever 29, and an end of a wire (not shown) drawn from a choke lever (also not shown) is connected to this wire attachment portion 29a. Idle screws 31 are also provided in the valve bodies 12, and a tip of this idle screw 31 regulates movement of the lever 29 in one direction by coming into contact with part of the lever 29. A regulated position of rotation of the lever 29 can also be adjusted by adjusting the extent to which the idle screws 31 are screwed in. Springs 32 are also provided on the shaft valve 26, to urge the shaft valve 26 in a direction of bringing the lever 29 into contact with the idle screws. That is, the shaft valve 26 is urged by the springs 32, and the lever 29 provided on the shaft valve 26 is brought into contact with the idle screws 31. If the extent to which the idle screws are screwed is then caused to fluctuate, the shaft valve 26 rotates and the amount of communication between the communication holes 27 of the shaft valve 26 and the second flow paths 24, namely the idle opening amount for each throttle, is collectively adjusted. If the wire connected to the wire attachment portion 29a is pulled, the lever 29 is rotated in the reverse direction, against the force of the spring 32, to rotate the shaft valve 26. In this way the communication holes 27 of the shaft valve 26 and the second flow paths 24 are collectively connected, the opening amount is increased, and the amount of intake air to the intake ports of each throttle body is increased. Specifically, this starting control valve assembly 11 can carry out favorable engine starting through increased intake air amount to each intake port, by pulling the wire connected to the lever 29. Further, extremely easy adjustment of the idle opening amount for each throttle can be performed by rotating the idle screws 31, and by carrying out rotational adjustment of tuning screws 21 for other throttles in accordance with a throttle constituting a reference, it is possible to carry out simple adjustment of idle opening amounts between cylinders for all of the throttles. In this way, the starting control valve assembly 11 of the above described embodiment has the tuning screws 21 provided for each cylinder provided together in a single valve body 12. Because this valve body 12 and each throttle body are connected through bypass tubes 10, the direction in which the tuning screws 21 face can be freely chosen, compared to the structure of the related art in which tuning screws 21 were respectively provided in each throttle body, without being restricted by the position at which the throttle body is arranged, and excellent layout design freedom is possible, thus making it possible to utilize space efficiently. Therefore, by using the starting control valve assembly 11 that has starter tuning screws 21 provided together in the valve bodies 12, adjustment of idle opening amount after being mounted in a motorcycle etc. can be carried out extremely easily from one side, and it is possible to reduce the time and effort required for vehicle maintenance. It is also possible to reduce the manufactured length of the flow path of the throttle body and the complexity of its shape, and in this way the manufacturing cost of the throttle body can be reduced. Using a single shaft valve 26 provided in the valve bodies 12 it is possible to collectively carry out idle adjustment for each throttle as well as the increase in air intake amount at the time of starting. Further, compared to the structure of the related art in which a multiple piston type starter valve is provided for each throttle body, the number of component parts can be substantially reduced, and the cost can be drastically reduced. Still further, since air is respectively supplied to the intake ports of each throttle body when idling and when starting through the second flow paths 24, no competition for air supply occurs between the cylinders, and it is possible to ensure stable idling. Also, seal members 28 are provided on the shaft valve 26 sandwiching the second flow paths 24, which means that it is possible to prevent leakage from these second flow paths 24. Fig. 4 shows a starting control valve assembly 11 having a control motor 35 connected to the end of the shaft valve 26. In this case, rotation of the shaft valve 26 is achieved through use of the control motor 35. That is, with this starting control valve assembly 11 engine idling open adjustment and fluctuation in intake at the time of starting can be electrically controlled by the control motor 35. Fig. 5 shows a link 41 attached to the end of the shaft valve 26, arid connected to this link 41 there is a rod 42 of a displacement device 43 for moving the rod 42 in response to temperature variation. This displacement device 43 contains wax, which varies in volume in response to temperature variation, so the temperature of the wax varies depending on the temperature of coolant supplied from a radiator. Accordingly, the rod 42 is moved in response to variations in volume of the wax and the shaft valve 26 is rotated through the link 41. In other words, in the case where this displacement device 43 has been provided, the shaft valve 26 is caused to rotate in response to variations in engine temperature, and it is possible to vary idling opening amount and intake when starting. In the above described starting control valve assembly 11, by making the diameter of the shaft valve 26 small, it is possible to make the clearance from the through holes small, and this makes it difficult for sticking of the shaft valve 26 to occur due to the intrusion of foreign matter etc. into clearance holes. In a starting control valve assembly, bypass tubes connecting intake ports of each throttle body are connected to joint pipes 16 of a starting control valve assembly 11. The starting control valve assembly 11 comprises valve bodies 12, communication paths 13 formed inside the valve bodies 12 and communicating with an air cleaner, first flow paths 17 and second flow paths 24 connecting the communication paths 13 and the joint pipes 16, tuning screws 21 for respectively adjusting opening amounts of each of the first flow paths 17, and a shaft valve 26 for collectively adjusting opening amounts of the second flow paths 24. Through holes are formed orthogonal to the second flow paths 24. The shaft valve 26 is rotatably provided inside the through holes 25. A plurality of communication holes 27 for respectively connecting the second flow paths 24 are formed in the shaft valve 26, all facing in the same direction. This is to simplify idle opening amount between each cylinder and simplify the structure of a throttle body.

Claims: A starting control valve assembly for a multiple throttle with multiple throttle bodies having intake ports for introducing a mixture to each combustion chamber of a multiple cylinder engine, for supplying air from an air cleaner to said intake ports via a bypass channel (10), comprising: valve bodies (12) having supply paths (16) with first ends connectable to each throttle body and respective remaining ends connectable to said intake ports; connection paths (13), formed in said valve bodies (12), connectable to said air cleaner; first flow paths (17) and second flow paths (24) for connecting said connection paths (13) and said supply paths (16); adjustment screws (21), respectively provided in said first flow paths (17), for adjusting respective open amounts of the first flow paths (17); and a shaft valve (26) rotatably provided within through holes crossing respective second flow paths (24), wherein a plurality of idle connection holes (27) respectively connected to said second flow paths (24) are formed in said shaft valve (26), facing in the same direction, and opening extents of said second flow paths (24) are adjusted together using said idle connection holes (27), by causing the shaft valve (26) to rotate. The starting control valve assembly for a multiple throttle as disclosed in claim 1, wherein seal members (28) are provided in said shaft valve (26) at positions interposed between said second flow paths (24), and each second flow path (24) is made airtight. The starting control valve assembly for a multiple throttle as disclosed in claim 1 or claim 2, wherein a control motor (35) is provided in said shaft valve (26), and said shaft valve (26) is rotatably adjusted using said control motor (35). The starting control valve assembly for a multiple throttle as disclosed in claim 1 or claim 2, wherein a rod (42) of a displacement device (43) causing movement of said rod (42) in response to temperature variations is connected to said shaft valve (26), and said shaft valve (26) is adjusted by said displacement device (43).

Inventors: AKAGI TAKASHI, KUBOTA TOSHIYUKI, AKAGI, TAKASHI, KUBOTA, TOSHIYUKI
Applicants: HONDA MOTOR CO LTD, HONDA GIKEN KOGYO KABUSHIKI KAISHA
Application year: 1998
Main classification: F02M13
IPC codes: F02M3, F02M13, F02D9