JP2020091000A - Fan clutch - Google Patents

Abstract

To provide a fan clutch which enables an engine and a cooling fan to be connected reliably in a case that the engine and the cooling fan are forcibly connected by a key member.SOLUTION: A fan clutch 1 disposed between an engine and a cooling fan of a vehicle includes: a driving body 2 driven by the engine; driven body 3 connected to the cooling fan; a switch mechanism 4 which switches a connection/disconnection state of the driving body 2 and the driven body 3; a key member 8 which enables the driving body 2 and the driven body 3 to connect with each other separately from the switch mechanism 4; and a fastening hole 2H which is provided at the driving body 2 or the driven body 3 and to which the key member 8 is attached through a bolt 9. The key member 8 has: a first through hole 8Ha through which the bolt 9 passes in a non-direct-coupled state; and a second through hole 8Hb through which the bolt 9 passes in a direct-coupled state.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fan clutch provided on a vehicle.

2. Description of the Related Art Conventionally, a fan clutch that switches a connection/disconnection state between an engine and a cooling fan based on a temperature of a coolant may be used between a cooling fan of a radiator provided in a vehicle and the engine (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2007-321622

By the way, in the fan clutch, in order to avoid a situation in which the cooling fan is stopped when the fan clutch is abnormal, a key member forcibly connecting the engine and the cooling fan (hereinafter, referred to as "direct connection key"). May be attached. This key member is generally provided on the side of a cooling fan or the like, and when it is desired to use a direct connection key, the fan clutch is connected via a bolt that can be fastened to a fastening hole (screw hole) provided in the fan clutch. Attached to. With such a fan clutch, when the key member is not used for a long time with the fastening hole open, foreign matter gets mixed into the fastening hole, and when you want to use the direct coupling key, the fixing of the direct coupling key is smooth. It may not be possible to

The fan clutch of the present invention has been devised in view of such a problem, and can reliably connect the engine and the cooling fan when it is necessary to forcibly connect the engine and the cooling fan by the key member. One of the purposes is to provide a possible fan clutch.

The fan clutch disclosed herein is a fan clutch interposed between an engine of a vehicle and a cooling fan, and includes a driving body driven by the engine, and a driven body connected to the cooling fan. A switching mechanism that switches the connection/disconnection state between the driving body and the driven body, a key member that can connect the driving body and the driven body separately from the switching mechanism, the driving body, or the A fastening hole which is provided in the driven body and to which the key member is attached via a bolt, wherein the key member is in a non-direct connection state in which the driving member and the driven body are not connected by the key member. In this case, a first through hole through which the bolt passes, and a second through hole through which the bolt passes in the case of a direct connection state in which the driving member and the driven member are connected by the key member, There is.

When the driving member and the driven member are not connected to each other by the key member, the bolt is fastened to the fastening hole through the first through hole provided in the key member. On the other hand, when the driving member and the driven member are directly connected by the key member, the bolt is fastened to the fastening hole through the second through hole provided in the key member. In this way, since the bolt is always fastened to the fastening hole through either the first through hole or the second through hole provided in the key member, it is possible to prevent foreign matter from entering the fastening hole.

According to the fan clutch of the present disclosure, the bolt is always fastened to the fastening hole through either the first through hole or the second through hole provided in the key member. Therefore, when it is necessary to connect the engine and the cooling fan, the driving member and the driven member can be reliably connected by the key member.

FIG. 3 is a schematic cross-sectional view of the fan clutch according to the embodiment, taken along the center of the rotation axis, showing a non-direct connection state. FIG. 3 is a schematic cross-sectional view of the fan clutch according to the embodiment cut along the center of the rotation axis, showing a direct connection state. It is a schematic diagram which shows the key member provided in the fan clutch of FIG. It is a typical sectional view which cut a fan clutch concerning one modification about a rotation axis.

A fan clutch as an embodiment will be described with reference to the drawings. The embodiments described below are merely examples, and are not intended to exclude various modifications and application of techniques that are not explicitly described in the following embodiments. Each configuration of the embodiment can be variously modified and implemented without departing from the spirit thereof. Also, they can be selected or combined as needed.

[1. Device configuration]
The fan clutch 1 according to the present embodiment is interposed between an engine mounted on a vehicle and a cooling fan (neither is shown). As shown in FIG. 1, the fan clutch 1 includes a driving body 2, a driven body 3 which is coaxial with the driving body 2 and is rotatable relative to the driving body 2 via a bearing, and a driving body 2. A switching mechanism 4 for switching the connection/disconnection state with the driven body 3 is provided.

The driving body 2 is connected to the crankshaft of the engine via a belt mechanism (not shown) and is driven by the engine. The driven body 3 is connected to a cooling fan, and when the driving body 2 and the driven body 3 are connected, the driving force of the engine is transmitted to rotate the driven body 3 and drive the cooling fan.

In the present embodiment, a viscous fan clutch 1 that exemplifies torque transmission by utilizing the viscosity of silicon oil flowing through the labyrinth-like flow path P formed by the driven body 3 and the drive body 2 is illustrated. The switching mechanism 4 includes a cover 5 that forms a space S for holding silicon oil, a bimetal 6 that deforms according to the ambient temperature of the fan clutch 1, and a valve plate 7 that is rotated by the bimetal 6, and the labyrinth. The connection/disconnection state is switched by switching whether or not silicon oil is supplied to the flow channel P.

Specifically, when the ambient temperature of the fan clutch 1 rises, the valve plate 7 is rotated by the bimetal 6 to open the inflow hole 5Ha provided in the cover 5. As a result, the silicone oil in the space S passes through the inflow hole 5Ha and is supplied to the labyrinthine flow path P, so that the driving body 2 and the driven body 3 are brought into a connected state. On the other hand, when the ambient temperature of the fan clutch 1 decreases, the valve plate 7 reversely rotates and returns to its original position, closing the inflow hole 5Ha. As a result, the silicon oil is not supplied to the labyrinth-like flow path P, and the driving body 2 and the driven body 3 are disconnected. The silicon oil left between the driving body 2 and the driven body 3 when the inflow hole 5Ha is closed is returned to the space S via the outflow hole 5Hb provided outside the inflow hole 5Ha in the rotation center. ..

In the fan clutch 1 configured as described above, the connection/disconnection state between the driving body 2 and the driven body 3 is appropriately controlled according to the ambient temperature of the fan clutch 1, thus contributing to power saving. On the other hand, if an abnormality occurs in the fan clutch 1 due to leakage of silicon oil or breakage of the bimetal 5, the connection/disconnection state may not be properly controlled.

Therefore, the fan clutch 1 of the present embodiment is provided with a direct connection key 8 (key member) capable of connecting the driving body 2 and the driven body 3 separately from the switching mechanism 4. The fan clutch 1 also includes a bolt 9 for mounting the direct connection key 8 and a fastening hole (screw hole) into which the bolt 9 is fitted. In the present embodiment, the fastening hole 2H provided in the driving body 2 is illustrated.

When the drive body 2 and the driven body 3 are not connected by the direct connection key 8, as shown in FIG. 1, the direct connection key 8 is attached to the drive body 2 by the bolt 9 at a position where the direct connection key 8 does not contact the driven body 3. Hereinafter, this state is referred to as "non-direct connection state". On the other hand, when the drive body 2 and the driven body 3 are connected by the direct connection key 8, the direct drive key 8 is driven by the bolt 9 at a position where the direct connection key 8 engages with the driven body 3 as shown in FIG. Attached to body 2. Hereinafter, this state is referred to as a "direct connection state". 1 and 2, hatching showing the cross section of the direct connection key 8 and the bolt 9 is omitted.

As shown in FIG. 3, the direct connection key 8 is a rectangular parallelepiped member having a plurality of through holes 8H into which the bolts 9 are inserted. The direct coupling key 8 has a first through hole 8Ha through which the bolt 9 passes in the non-direct coupling state and a second through hole 8Hb through which the bolt 9 passes in the direct coupling state. In this embodiment, the first through hole 8Ha and the second through hole 8Hb that are orthogonal to each other in the direct connection key 8 are illustrated.

The first through hole 8Ha is provided along the long side of the direct connection key 8 as shown by the long broken line in FIG. The second through hole 8Hb is provided along the short side of the direct connection key 8Hb at a position displaced from the center of the long side of the direct connection key 8 as shown by the short dashed line in FIG. The two through holes 8Ha and 8Hb are provided so as to penetrate the direct coupling key 8 with a diameter slightly larger than the diameter of the threaded portion of the bolt 9.

Further, the first through hole 8Ha of the present embodiment is provided with a counterbore processing in such a shape that the head of the bolt 9 fits into the portion on the side where the bolt 9 is inserted. This counterboring is performed in order to equalize the length X where the threaded portion of the bolt 9 meshes with the first through hole 8Ha and the length X where the threaded portion of the bolt 9 meshes with the second through hole 8Hb. .. In other words, the counterbore processing is performed to equalize the lengths of the bolts 9 protruding from the direct connection key 8 when the bolts 9 are fitted into the two through holes 8Ha and 8Hb, respectively. In this embodiment, the bolt 9 is a hexagonal star-shaped bolt, and the portion of the first through hole 8Ha on the side where the bolt 9 is inserted has a diameter slightly larger than the diameter of the bolt head of the bolt 9. Is processed in.

As shown in FIG. 1 and FIG. 2, in the driving body 2 to which the direct coupling key 8 is attached, a part of a surface portion 2F facing the driven body 3 and an outer peripheral surface is notched so as to fit the direct coupling key 8. A notch 2C is provided. The fastening hole 2H is provided along the radial direction of the driving body 2 on the rotary shaft side with respect to the cutout portion 2C, and is provided at a position where it can communicate with both of the two through holes 8Ha and 8Hb.

The cutout portion 2C is formed by cutting the driving body 2 so that each side forms a rectangular parallelepiped space along the axial direction, the radial direction, and the circumferential direction of the driving body 2. The axial dimension of the cutout portion 2C is set to be substantially the same as the dimension of the short side of the direct connection key 8. As a result, when the direct coupling key 8 is fitted such that the short side of the direct coupling key 8 extends along the axial direction, the direct coupling key 8 does not project to the driven body 3 side from the surface portion 2F (see FIG. 1). On the other hand, when the direct coupling key 8 is fitted such that the long side of the direct coupling key 8 extends along the axial direction, the direct coupling key 8 projects toward the driven body 3 side from the surface portion 2F (see FIG. 2).

Further, the driven body 3 is provided with a notch portion 3C which is notched in a shape in which the direct connection key 8 fits in a part of a surface portion 3F of the driving body 3 facing the driven body 2. The cutout portion 3C is formed by cutting the driving body 3 so that each side forms a rectangular parallelepiped space along each of the axial direction, the radial direction, and the circumferential direction of the driving body 3, like the cutout portion 2C. It As a result, when the direct coupling key 8 is fitted so that the long side of the direct coupling key 8 extends along the axial direction, a part of the direct coupling key 8 protruding toward the driven body 3 side from the surface portion 2F is cut out 2C. (See FIG. 2).

[2. Action]
Next, the operation of the direct connection key 8 and the fan clutch 1 will be described.

In the non-direct coupling state, as shown in FIG. 1, the direct coupling key 8 is fitted into the notch 2C of the driving body 2 so that the first through hole 8Ha of the direct coupling key 8 and the fastening hole 2H of the driving body 2 communicate with each other. Then, the direct connection key 8 is attached to the driving body 2 by the bolt 9. At this time, since the direct connection key 8 is fitted into the cutout portion 2C so that the short side of the direct connection key 8 perpendicular to the first through hole 8Ha is along the axial direction, the driven body 3 is more than the surface portion 2F of the drive body 2. It does not project to the side and does not contact the driven body 3. In this state, the connection/disconnection state between the driving body 2 and the driven body 3 is switched by the switching mechanism 4. Further, at this time, since the fastening hole 2H is closed by the bolt 9, it is difficult for foreign matter to enter the fastening hole 2H.

When switching from the non-direct connection state to the direct connection state, the bolt 9 inserted in the first through hole 8Ha is pulled out, the direct connection key 8 is rotated 90 degrees, and the direction of the direct connection key 8 is changed. Further, the direct connection key 8 is fitted into the cutout portion 2C of the drive body 2 so that the second through hole 8Hb of the direct connection key 8 and the fastening hole 2H of the drive body 2 communicate with each other, and the direct connection key 8 is fixed by the bolt 9. When attached to the driving body 2, the direct connection key 8 is in a direct connection state. At this time, since the fastening hole 2H is held in the non-directly connected state in a state of being closed by the bolt 9, as described above, it is difficult for foreign matter to enter the fastening hole 2H, and the direct connection key 8 is fixed. Can be smooth.

In the direct connection state, as shown in FIG. 2, the direct connection key 8 is fitted into the notch 2C so that the long side of the direct connection key 8 which is perpendicular to the second through hole 8Hb is fitted in the cutout portion 2C so as to extend along the axial direction. It is in a state of protruding toward the driven body 3 side from the surface portion 2F. The protruding portion fits into the cutout portion 3C of the driven body 3. As a result, the driving body 2 and the driven body 3 are forcibly connected. Therefore, when the driving body 2 is driven, the driven body 3 is driven via the direct connection key 8 regardless of the operating state of the switching mechanism 4. Therefore, when an abnormality occurs in the fan clutch 1, it is possible to avoid that the cooling fan does not operate even though it needs to be cooled by the cooling fan.

[3. effect]
According to the fan clutch 1 described above, the bolt 9 is always fastened to the fastening hole 2H through either the first through hole 8Ha or the second through hole 8Hb provided in the direct connection key 8, so that the bolt 9 is fastened. The hole 2H can be always closed. Therefore, the fastening hole 2H is not opened even in the non-directly connected state, so that it is possible to prevent foreign matter from entering the fastening hole 2H in the non-directly connected state. Therefore, when it is desired to forcibly connect the engine and the cooling fan, the fixing of the bolt 9 is not hindered by the foreign matter mixed in the fastening hole 2H, and the driving body 2 and the driven body 3 are directly connected by the key 8. It can be surely connected.

Further, in the above-described fan clutch 1, the rectangular parallelepiped direct connection key 8 is fixed to the drive body 2 by changing the direction between the non-direct connection state and the direct connection state, so that the notch portion 2C of the drive body 2 is made small. be able to. Therefore, the direct connection key 8 can be attached even to the drive body 2 having no allowance in the axial dimension, and the fastening hole 2H can be always closed by the bolt 9.

[4. Modification]
The configuration of the fan clutch 1 described above is an example. The direct connection key 8 provided on the fan clutch 1 is connected to the drive body 2 and the driven body 3 by changing the direction and being fastened to the drive body 2. However, the configuration of the direct connection key 8 is as follows. Is not limited to this.

For example, the direct connection key 8'may have a first through hole 8Ha' and a second through hole 8Hb' which are provided in parallel along the short side as shown in FIG. In this case, the axial dimension of the cutout portion 2C' may be set to be substantially the same as or larger than the dimension of the long side of the direct connection key 8'. When the first through hole 8Ha' and the second through hole 8Hb' of the direct connection key 8'are provided in parallel along the short side, the direct connection key 8'does not require a spot facing for accommodating the bolt head. Therefore, the structure of the direct connection key 8'can be further simplified.

Further, in the present embodiment, the bimetal type fan clutch 1 is illustrated, but the fan clutch may be an electronically controlled type instead of the bimetal type. Further, although the viscous type fan clutch 1 is illustrated in the present embodiment, the fan clutch may be an electromagnetic type. In the present embodiment, the cutouts 2C and 3C are provided, but instead of the cutouts, a fixing portion that fixes the position of the direct connection key is projected from each of the driving body 2 and the driven body 3. It may be provided.

1 Fan Clutch 2 Drive Body 2H Fastening Hole 3 Driven Body 4 Switching Mechanism 8, 8'Direct Connection Key (Key Member)
8Ha, 8Ha' First through hole 8Hb, 8Hb' Second through hole 9 Bolt

Claims (1)

A fan clutch interposed between a vehicle engine and a cooling fan,
A driving body driven by the engine,
A driven body connected to the cooling fan;
A switching mechanism that switches the connection/disconnection state between the driving body and the driven body,
A key member capable of connecting the driving body and the driven body separately from the switching mechanism,
A fastening hole provided in the driving body or the driven body, to which the key member is attached via a bolt,
The key member includes a first through hole through which the bolt passes when the driving member and the driven member are not connected to each other by the key member, and the driving member and the driven member by the key member. And a second through hole through which the bolt passes in the case of a direct connection state.

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