JP2014009724A - Power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission device in which engine drive and motor drive are both used, in a simple way and at low cost.SOLUTION: The power transmission device includes: a sprocket 7 having teeth 23 provided on the outer circumference and fitted into a gap formed in a power transmission chain 4; and a motor 8 driven by a battery 9, for rotating the sprocket 7. In the power transmission device, both engine drive in which the power transmission chain 4 is driven by rotating a primary pulley 2 by an engine 5 and motor drive in which the power transmission chain 4 is driven by rotating the sprocket 7 can be used.

Description

  The present invention relates to a power transmission device suitable for a continuously variable transmission (CVT) of a vehicle such as an automobile.

  As a power transmission device such as a continuously variable transmission for an automobile, a primary pulley to which driving force is input from an engine, a secondary pulley that outputs driving force to a driving wheel, and a power transmission chain wound around both pulleys What you have is known.

  As a power transmission chain, one having a plurality of links and a plurality of connecting members (first pin and second pin) for connecting the plurality of links so as to be bent is known (Patent Document 1). .

JP 2009-228702 A

  In power transmission devices such as continuously variable transmissions for automobiles, a system (hybrid system) that combines a system that drives a power transmission chain by rotating a pulley with an engine and a system that drives a power transmission chain with a motor is adopted. May be. In this case, in order to transmit the driving force of the motor to the power transmission chain, a planetary gear or a clutch needs to be installed on the power transmission chain. For this reason, combining the drive system of the power transmission chain by the motor with the existing power transmission apparatus that only uses the system of driving the power transmission chain by rotating the pulley with the engine is troublesome and costly. There was a problem that it took.

  The present invention has been made in view of the above problems, and an object thereof is to provide a power transmission device in which engine driving and motor driving are used in a simple and low cost manner.

  A power transmission device according to the present invention includes a primary pulley to which a driving force is input from an engine, a secondary pulley, and a power transmission chain wound around the primary pulley and the secondary pulley. In the power transmission device having a plurality of links and a plurality of connecting members that connect the plurality of links so as to be bendable, a sprocket having teeth inserted into a gap of the power transmission chain on the outer periphery, and the sprocket And a motor for driving the power transmission chain by rotating the primary pulley by the engine, and driving the power transmission chain by rotating the sprocket by the motor. Can be used with motor drive Than is.

  According to the power transmission device of the present invention, it is possible to use both engine driving and motor driving in a simple and low cost manner.

FIG. 1 is a front view showing an embodiment of a power transmission device according to the present invention. 2 is a cross-sectional view taken along the line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG.

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

  1 to 3 show an embodiment of a power transmission device according to the present invention.

  As shown in FIG. 1, the power transmission device (1) includes a primary pulley (2), a secondary pulley (3), a power transmission chain (4) wound around both pulleys (2) and (3), An engine (5) for driving the primary pulley (2) and a motor (8) for driving the power transmission chain (4) are provided.

  The power transmission device (1) is used as a continuously variable transmission for a vehicle driven by an engine (5). A driving force is input from the engine (5) to the primary pulley (2), and this driving force is output to the driving wheel side via the power transmission chain (4) and the secondary pulley (3).

  Between the primary pulley (2) and the secondary pulley (3), there is a sprocket (7) meshed with the string part of the power transmission chain (4) (the part not regulated by the pulley (2) (3)) Has been placed. The sprocket (7) is rotated by a motor (8). The motor (8) is connected to a battery (power source) (9). The engine (5) and the motor (8) are controlled by the control devices (6) and (10), respectively.

  In the power transmission device (1), the underdrive (hereinafter referred to as “U / D”) having the maximum speed ratio corresponding to low speed traveling and the overdrive (hereinafter referred to as “U / D”) corresponding to the high speed traveling are minimum. "O / D")) and the gear ratio changes. FIG. 1 shows the O / D state, where the winding diameter of the power transmission chain (4) on the primary pulley (2) side is the maximum, and the power transmission chain (4) on the secondary pulley (3) side is wound. The diameter is the smallest. In the U / D state, the winding diameter of the power transmission chain (4) on the primary pulley (2) side is minimum, and the winding diameter of the power transmission chain (4) on the secondary pulley (3) side is maximum.

  The power transmission chain (4) includes a plurality of links (11), a plurality of first pins (14), and a plurality of second pins (15).

  As shown in FIG. 2, the link (11) has a front through hole (12) located on the front side in the chain traveling direction and a rear through hole (13) located on the rear side in the chain traveling direction. The links (11) are overlapped so that the front through-hole (12) of one link (11) on the rear side in the traveling direction and the rear through-hole (13) on the other link (11) on the front side in the traveling direction correspond to each other. ing. Each first pin (14) and each second pin (15) are fitted into a plurality of front through holes (12) and rear through holes (13) overlapping in the chain width direction.

  The first pin (14) and the second pin (15) are relatively rolled and brought into contact with each other, whereby the links (11) can be bent. The first pin (14) and the second pin (15) constitute a connecting member that connects the plurality of links (11) in a bendable manner.

  As shown in FIG. 1, the sprocket (7) includes a rotating shaft (21), a pair of disk portions (22) provided integrally with the rotating shaft (21), and each disk portion (22). It consists of a plurality of teeth (23) arranged around. The sprocket (7) is disposed so as to be located at approximately the center of the distance between the axes of the primary pulley (2) and the secondary pulley (3). The rotating shaft (21) is connected to the motor (8), whereby the sprocket (7) is rotated by the motor (8) using the battery (9) as a power source.

  As shown in FIG. 2, the power transmission chain (4) has an end portion of the first pin (14) inserted through the front through hole (12) and a second pin (through the rear through hole (13)). A gap (G) exists between the ends of 15). The teeth (23) of the sprocket (7) are shaped to fit into the gap (G) and mesh with the first pin (14). As shown in FIG. 3, the teeth (23) of the sprocket (7) are formed so as to mesh with both end portions of the first pin (14). The axial center position of the sprocket (7) is fixed, and the teeth (23) of the sprocket (7) and the first pin (14) are always meshed with each other.

  When the sprocket (7) is rotated because the teeth (23) of the sprocket (7) and the first pin (14) mesh with each other, the first pin (14) is moved in the direction of chain movement. The power transmission chain (4) is driven.

  The energy efficiency of the engine (5) is high when in the O / D state (during high speed running) and is low during the U / D state (during start-up or low speed running).

  The power transmission chain (4) in the power transmission device (1) can be driven by rotating the primary pulley (2) by the engine (5), as in the prior art. This is engine drive, and conventionally, the power transmission chain (4) was driven only by this engine drive. In the power transmission device (1), the drive of the primary pulley (2) by the engine (5) is stopped and the sprocket (7) is rotated by the motor (8) to drive the power transmission chain (4). Can be made. This is motor drive, and in the power transmission device (1), engine drive and motor drive can be used in combination.

  The motor (8) receives the power supply from the battery (9) and rotates the sprocket (7), and also converts the rotation of the sprocket (7) into electric power and stores it in the battery (9) (Charger function). When the engine is driven, power supply to the motor (8) is stopped. As a result, the motor (8) cannot rotate the sprocket (7). However, since the teeth (23) of the sprocket (7) and the first pin (14) are always meshed, the sprocket (7) rotates when the power transmission chain (4) is driven by the engine drive. Electricity is generated with the rotation of the sprocket (7). The electric power obtained by power generation is stored in the battery (9). Thus, the function of the charger is given to the motor (8).

  The control device (10) of the motor (8) functions to drive the sprocket (7) by the motor (8) based on the rotational speed of the engine (5), the vehicle speed, etc., and the motor (8) functions as a charger. Switch the state to be activated. Further, the control device (10) of the motor (8) increases or decreases the rotational speed of the sprocket (7) as necessary.

  In the power transmission device (1), the engine drive and the motor drive can be used together to move the power transmission chain (4). The power transmission chain (4) is moved by driving the engine. At this time, since the motor (8) functions as a charger, it is possible to reduce fuel consumption by storing the obtained electric power in the battery (9).

  At the time of start-up or low-speed running where the energy efficiency of the engine (5) is low, the power transmission chain (4) is moved by motor drive. As a result, it is not necessary to use the engine (5) under conditions of poor energy efficiency, and fuel consumption can be reduced.

  In order to use both engine drive and motor drive, the output shaft of the engine (5) and the shaft of the primary pulley (2) are usually connected, and the output shaft of the motor (8) and the primary pulley (2). A device for switching between the state where the shafts are connected to each other is required. As a device for switching, for example, there is a planetary gear device, a clutch or the like, but if such a device is used, there is a problem that the cost is high and the power transmission device (1) is enlarged. On the other hand, in the power transmission device (1), the teeth (23) of the sprocket (7) and the first pin (14) are utilized by utilizing the gap (G) formed in the power transmission chain (4). By disposing them so as to mesh with each other, it is not necessary to connect the output shaft of the motor (8) and the shaft of the primary pulley (2). Thereby, in the power transmission device (1), an additional device for driving the motor can be simplified, and the combined use of the engine drive and the motor drive can be achieved at low cost.

  The string part between the pulleys (2) and (3) in the power transmission chain (4) is not regulated by the pulleys (2) and (3), so it vibrates in the direction perpendicular to the traveling direction (string vibration) This may cause noise characteristics to deteriorate. In the power transmission device (1), the teeth (23) of the sprocket (7) are engaged with the strings of the power transmission chain (4), so that the direction of travel of the strings of the power transmission chain (4) is orthogonal. The movement in the direction to be controlled is restricted, and the string vibration is reduced.

(1): Power transmission device, (2): Primary pulley, (3): Secondary pulley, (4): Power transmission chain, (5): Engine, (7): Sprocket, (8): Motor, (9 ): Battery (Power), (11): Link, (14): First pin, (15): Second pin, (23): Teeth

Claims (2)

A primary pulley to which driving force is input from the engine; a secondary pulley; and a power transmission chain wound around the primary pulley and the secondary pulley. The power transmission chain includes a plurality of links, the plurality of links In the power transmission device having a plurality of connecting members for connecting the link so as to be bent,
An engine for driving the power transmission chain by rotating the primary pulley by the engine, further comprising a sprocket having teeth inserted into a gap of the power transmission chain on an outer periphery, and a motor for rotating the sprocket. A power transmission device capable of using both driving and motor driving for driving the power transmission chain by rotating the sprocket by the motor.   The state where the motor drive is stopped and only the engine drive is used, the sprocket is rotated by driving the power transmission chain, and the motor connected to the rotating sprocket functions as a charger. 1 power transmission device;

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