JP2961895B2 - Reduction gear for driving a speedometer cable of a gear transmission for automobiles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed reducer for driving a speedometer cable of a gear transmission for an automobile, and more particularly to a positioning of a sleeve which supports a driven gear of the speed reducer.

[0002]

2. Description of the Related Art A gear transmission for an automobile is provided with a reduction gear for driving a speedometer cable, and the reduction gear includes a driven gear connected to an output shaft of the gear transmission. The driven gear is fitted into a sleeve fixed to a casing of the gear transmission.

Therefore, as shown in FIG. 5, the sleeve is positioned and fixed to the casing by bolts. That is, a hole 15 for passing the bolt 10 is provided in the sleeve 11. At the time of assembling, the sleeve 11 and the driven gear 12 are integrally inserted into the casing 17. Next, the sleeve 11 is inserted until the distal end portion 12 a of the driven gear 12 in the axial direction comes into contact with a stopper 17 a provided on the inner wall of the casing 17.

However, if the driven gear 12 and the casing 17 rotate in contact with each other, the rotation resistance of the driven gear 12 increases, causing a problem of wear and seizure of the tooth surface.

Therefore, a hole 15 provided in the sleeve 11 is provided.
Is set to match the position of the bolt 10 at the position where the driven gear 12 and the stopper 17a come into contact with each other.
A gap 16 is provided between the bolt 5 and the bolt 10 in advance.
As a result, the thrust force generated when the driven gear 12 meshes with the output shaft side causes the driven gear 12 itself to move in the axial direction by the gap 16 so that a gap is provided between the driven gear 12 and the casing 17. I was

[0006]

However, the above conventional apparatus has the following problems.

[0007] Seal members 13, 14, and 15 are provided between the sleeve 11 and the casing 17 and between the sleeve 11 and the driven gear 12, respectively. These seal members prevent leakage of the lubricating oil in the casing 17 and prevent water from entering from outside the casing. Therefore, the sealing member needs to ensure extremely high sealing performance. Therefore, the sliding resistance of the sleeve 11 due to the sealing members 13 and 14 is reduced when the casing 1 is assembled.
7 is larger than the thrust force generated from the screw gear used for speed reduction.
As a result, the driven gear 12 cannot move by the thrust force against the sliding resistance.
And the casing 17 is kept in contact with each other. Accordingly, the rotational resistance of the driven gear 12 is increased, and there is a problem that wear and seizure of the tooth surface occur.

In order to prevent the driven gear 12 and the casing 17 from coming into contact with each other, the
It is necessary to pull back a little after inserting 1 into casing 17 once. However, in this case, it is difficult to match the positions of the holes 15 and the bolts 10, and there is a problem that the assembling time is long and the productivity does not match.

In view of the above, the present invention provides a stop gear which pushes a sleeve in an axial direction and a rotational direction by an axial force of a bolt to restrict the axial movement of a driven gear and a driven gear provided on an inner wall of a casing. The object of the present invention is to eliminate the need for adjusting the position between the positioning hole of the sleeve and the bolt at the time of assembly by securing a gap between the positioning holes and guiding the bolt to the positioning hole for the sleeve.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the conventional apparatus, the present invention provides a cylinder portion formed on an inner wall of a casing of an automobile gear transmission, a sleeve fitted to the cylinder portion, and a sleeve inside the sleeve portion. The driven gear, which is inserted into the through hole formed in the driven gear and meshes with the output shaft side of the gear transmission, the seal member and the sleeve which are respectively disposed between the driven gear and the sleeve and between the cylinder portion and the sleeve. A positioning hole for a sleeve to be bored and screwed with a bolt, a driven gear and a driven gear provided on the inner wall of the casing by pushing the sleeve in the axial and rotational directions by the axial force of the bolt provided in the sleeve positioning hole. A guide is provided to secure a gap between the gear and the stopper for restricting the movement of the gear in the axial direction, and to guide the bolt to the sleeve positioning hole.

[0011]

FIG. 1 is a longitudinal sectional view of an embodiment of the apparatus according to the present invention.

A cylinder portion 1b is formed on an inner wall of a casing 1 for housing a gear transmission (not shown).
A sleeve 3 is slidably fitted in the cylinder portion 1b. A through hole 3a is formed in the axis of the sleeve 3, and one end of a driven gear 4 constituting a reduction gear (not shown) for driving a speedometer cable (not shown) is rotatably supported. I have. The other end of the driven gear 4 is meshed with a drive gear 9 which is connected and fixed to an output shaft 9 of a gear transmission (not shown).

The sleeve 3 is provided with seal members 6, 7, 8 for preventing the leakage of the lubricating oil in the casing 1 and for preventing water from entering from outside the casing. In addition, a high sealing property is maintained between the driven gear 4 and the sleeve 3.

FIG. 2 is an enlarged sectional view of a fitting portion of the sleeve 3 and the bolt 2. The sleeve 3 is provided with a positioning hole 3 a for positioning the bolt 2.
A conical guide portion 3b for facilitating the assembling is formed with a chamfer.

The operation of the above embodiment at the time of assembly will be described below.

FIG. 3 is a diagram showing an assembled state based on the above configuration, and FIG. 4 is a diagram showing an assembled state.

In FIG. 3, the sleeve 3 is fitted into the cylinder 1b integrally with the driven gear 4. At this time, the force for pushing the sleeve 3 needs to overcome the large sliding resistance of the sealing members 6 and 7. Therefore, as a work, the sleeve 3 is inserted by a strong external force until the end face 4a of the driven gear 4 always comes into contact with the stop face 1a provided on the inner wall of the casing 1. In this state, when the bolt 2 is fastened to the hole of the sleeve 3, the end surface 2a of the bolt 2 is guided by the conical guide portion 3b. Further, when the bolt 2 is tightened, the sleeve 3 is pushed in the arrow A direction by the rotational force of the bolt 2. As a result, as shown in FIG. 4, a gap X is secured between the end face 4a of the driven gear 4 and the stopper 1a of the casing 1. Therefore, the driven gear 4 does not rotate in a state where the driven gear 4 and the casing 1 are in contact with each other, and the tooth surfaces of the driven gear 4 do not wear or seize.

In the conical guide portion 3b, the difference Y in the radial direction between the conical guide portion 3b and the positioning hole 3a is set to be larger than the gap X between the driven gear 4 and the casing 1 at the insertion port of the bolt 2. Have been. As a result, bolt 2
There is no need for axial alignment of the positioning hole 3a with the positioning hole 3a, and the assembling property is improved.

[0019]

As described above, the speed reducer for driving the speedometer cable of the gear transmission for an automobile according to the present invention has the following features.
By forming a conical guide in the positioning hole of the sleeve, the sleeve can be pushed in the axial and rotational directions by the axial force of the bolt, and between the end face of the driven gear and the stopper of the casing. A gap can be secured. Therefore, there is no problem that the tooth surface of the driven gear is worn and seized.

Further, since the bolt is guided by the conical guide portion, there is no need to align the positioning hole of the sleeve with the bolt in the axial direction. As a result, it is possible to provide an apparatus which is easy to assemble and suitable for mass production. Further, since the component tolerance can be allowed by freely changing the radial difference between the conical guide portion and the positioning hole, the shape processing is facilitated. Therefore, the processing cost is minimized.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a speed reduction device for driving a speedometer cable of an automotive gear transmission according to the present invention.

FIG. 2 is an enlarged sectional view of a fitting portion of a sleeve and a bolt in FIG.

FIG. 3 is a diagram showing an assembled state of the device of the present invention.

FIG. 4 is a view showing a completed assembly state of the apparatus of the present invention.

FIG. 5 is a diagram showing an assembled state of a conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 1a Stopper surface (stopper part) 2 Bolt 3 Sleeve 3a Sleeve positioning hole 3b Conical guide part (guide part) 4 Follower gear 6, 7, 8 Seal member 9 Output shaft of gear transmission

Claims (1)

(57) [Claims] An output shaft of the gear transmission, which is inserted into a cylinder formed on an inner wall of a casing of a gear transmission for an automobile, a sleeve fitted to the cylinder, and a through hole formed in the sleeve. Driven gear engaged with the side, seal members respectively disposed between the driven gear and the sleeve, and between the cylinder portion and the sleeve, positioning for the sleeve which is bored in the sleeve and into which a bolt is screwed. The axial movement of the driven gear and the driven gear provided on the inner wall of the casing by pushing the sleeve in the axial and rotational directions by the axial force of the bolt provided in the hole and the positioning hole for the sleeve. Speed meter casing for an automotive gear transmission, comprising a guide portion for securing a gap between the stopper portion and a guide portion for guiding the bolt to a sleeve positioning hole. Speed reducer for bull drive.