Multiple-displacement engine

• US 4,556,026 A
• Filed: 03/18/1985
• Issued: 12/03/1985
• Est. Priority Date: 08/31/1983
• Status: Expired due to Fees

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Masuda, Shunji, Okazaki, Katumi, Nakaya, Hisashi
• Primary Examiner(s): Lazarus, Ira S.
• Application Number:
  US06/712,915
• Time in Patent Office: 260 Days
• Field of Search: 123/198 F, 123/192 B, 123/DIG. 6, 123/DIG. 7
• US Class Current: 123/198.00F
• CPC Class Codes: F01L 13/00 Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
• CPC Class Codes: F02B 2075/027 four
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: F16F 15/26 of crankshaft systems using solid masses, other than the ordinary pistons, moving with the system , i.e. masses connected through a kinematic mechanism or gear system F16F15/226 takes precedence

Abstract

A multiple-displacement engine which can be operated either in a full-displacement state in which all the cylinders are operative or a part-displacement state in which a part of the cylinders are inoperative is provided with a balancer for attenuating torque fluctuation due to explosion in the operative cylinders in the part-displacement state of the engine. The engine is further provided with a balancer actuator which actuates the balancer when the engine is operated in the part-displacement state.

Claims

1. A multiple-displacement engine which can be operated either in a full-displacement state in which all the cylinders thereof are operative or a part-displacement state in which a part of the cylinders are inoperative, and comprises fuel supply interruption means for cutting fuel supply to a part of the cylinders, operating condition detecting means for detecting operating condition of the engine, and cylinder number control means which determines the number of cylinders to be supplied with fuel according to a signal from the operating condition detecting means and actuates the fuel supply interruption means, characterized by having balancer means for generating moment which attenuates torque fluctuation due to explosion in the operative cylinders in the part-displacement state of the engine, and balancer actuating means which receives a control signal from the cylinder number control means and actuates the balancer when the engine is operated in the part-displacement state.

2. A multiple-displacement engine as defined in claim 1 in which said balancer means comprises a balancer shaft extending in parallel to the crankshaft of the engine and a weight eccentrically provided on the balancer shaft, and is adapted to be driven by the crankshaft by way of clutch means.

3. A multiple-displacement engine as defined in claim 2 in which said clutch means is disposed between the balancer shaft and the crankshaft, and said balancer actuating means comprises the clutch means and timing control means which connects the balancer shaft to the crankshaft in a predetermined phase in response to a cylinder-reduction signal from the cylinder number control means.

4. A multiple-displacement engine as defined in claim 3 in which said timing control means comprises position detecting means for detecting the positions of the crankshaft and the balancer shaft, gate means provided between the cylinder number control means and the clutch means, and timing determination means which outputs a signal for opening the gate means at a predetermined time in response to a signal from the gate means.

5. A multiple-displacement engine as defined in claim 2 in which said balancer shaft includes an even number of shafts and is arranged to statically balance by itself, the balancer shaft being adapted to be rotated in the direction opposite to the crankshaft.

6. A multiple-displacement engine as defined in claim 2 in which a pair of said weights are provided on opposite ends of the balancer shaft.

7. A multiple-displacement engine as defined in claim 1 in which said operating state detecting means comprises an engine load sensor and said cylinder number control means actuates said fuel supply interruption means to change the operating state of the engine to the part-displacement state when load on the engine is lighter than a predetermined value.

8. A multiple-displacement engine as defined in claim 7 in which said operating state detecting means further comprises an engine speed sensor for detecting the engine speed and said cylinder number control means actuates said fuel supply interruption means to change the operating state of the engine to the part-displacement state when the engine speed is lower than a predetermined value.