JPH02150548A - Frame accuracy keeping and positioning structure of gear box - Google Patents

Abstract

PURPOSE:To keep an essential function without troublesome manufacture and extra seat by pressing a hollow knock pin in a knock pin hole disposed on a fitting bolt portion and then fixing a casing and a bracket by a fitting bolt. CONSTITUTION:Knock pin insert holes 1c and 2c where a knock pin 3 can be inserted with interference concentrically with a fitting bolt hole 2b and a fitting bolt screw hole 1b are disposed opposite to each other on casing 1 side and on bracket 2 side. On the other hand, a knock pin 3 having a through- hole 3 a little larger than the outside diameter of a fitting bolt 4 and interference a little larger than the knock pin insert holes 1c, 2c is pressed in the knock pin holes 1c, 2c, a bracket 2 is joined, the fitting bolt 4 is fastened to form a gear box. In such a structure, an essential positioning function is kept without the need of extra seat and boring in addition to a fitting bolt seat. Furthermore, the knock pin 3 is prevented from slipping out in the axial direction due to vibration or the like during operation, and the quality and function of a product can be kept.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides a structure that enables a positioning function in order to maintain frame accuracy of a gear box.

[Conventional technology]

The conventional technique will be explained with reference to FIG.

A gear box composed of a casing 1 and a bracket 2 has a structure in which the gears mesh through bearings provided on the casing and the bracket 2, respectively.

Due to the nature of gears, gear boxes require severe machining accuracy and mounting accuracy. Therefore, dowel pin seats are provided at locations other than the multiple mounting bolt positions, and the frame is machined based on the dowel pin hole machining to facilitate assembly. In this case, the spigots 1a and 2a are provided on the casing and the bracket, respectively, and the spigots are joined,
In addition to tightening with a plurality of mounting bolts 4, the dowel pin 3 is press-fitted into the dowel hole 2C, thereby maintaining the severe frame precision of the gear box.

According to this structure, in addition to machining multiple bolt seats and holes, extra dowel pin seats and dowel pin holes are machined.
This requires a lot of processing time, and since a seat other than the bolt seat is provided, the gear box becomes large in order to prevent interference between the internal gear and the seat, which hinders compact metering. In addition, there is a possibility that the dowel pin may move in the axial direction due to vibrations during operation and be pulled out to the outside, resulting in a decrease in the quality of the product.

Regarding the alignment of the gear case and motor in a gear motor using a dowel pin, please refer to Japanese Patent Publication No. 63-2.
The disclosure is in No. 7941.

[Problem to be solved by the invention]

As mentioned above, in the conventional technology, the machining accuracy and assembly of the casing and bracket are improved by providing extra dowel pins and dowel pin mounting holes in locations other than the multiple mounting bolts that connect the casing and bracket, and press-fitting the dowel pins. Precision was maintained. This not only made manufacturing difficult, but also made it difficult to make the gear box compact and weighable.

Furthermore, there is a possibility that the dowel pin moves in the axial direction due to vibrations during operation and is pulled out to the outside, resulting in a decrease in the quality of the product.

SUMMARY OF THE INVENTION An object of the present invention is to provide a gear box that solves the problems of the prior art and can maintain its original function without the need for complicated manufacturing or the provision of extra seats.

[Means to solve the problem]

The above object is to provide dowel pin mounting holes concentrically at the same location in the bolt seat and bolt hole of the mounting bolt that joins the casing and the bracket.

Further, this is achieved by press-fitting a hollow knock pin having an inner diameter (bolt mounting hole diameter) slightly larger than the outer diameter of the mounting bolt into the knock pin hole, and then tightening the mounting bolt to fix the casing and the bracket.

[Effect]

By press-fitting a hollow dowel pin into the dowel pin mounting hole, which is provided at the same location as the multiple mounting bolts that connect the casing and the bracket and concentrically with the bolt holes, interference between the gear in the gear box and the dowel pin mounting seat is prevented. Moreover, it becomes possible to position the casing and the bracket, and it becomes possible to maintain the original function without the need for extra hole drilling or seats.

Roughly tightening the mounting bolts and fixing the casing and bracket prevents the dowel pin from moving in the axial direction and coming out due to vibrations during operation, maintaining product quality and functionality. becomes possible.

〔Example〕

The present invention will be explained in detail with reference to FIGS. 1 and 2.

In a gear box in which a concave spigot 1as and a convex spigot 2& are provided at the joint between the casing 1 and the bracket 2, and a plurality of mounting bolt screw holes 1b and a plurality of mounting bolt holes 2b are provided facing each other, the mounting bolt hole 2b and the mounting bolt hole 2b are provided oppositely. Knock pin insertion holes 1c and 2c are provided on the casing side and the bracket side, respectively, so as to face each other and allow the dowel pin 3 to be inserted concentrically into the bolt screw hole 1b while holding the shim.

On the other hand, the dowel pin 3 has a through hole 3a that is slightly larger than the outer diameter of the mounting bolt 4 (same diameter as the mounting bolt hole 2b), and has an outer diameter that is slightly offset from the dowel pin insertion holes 1c and 2c. By press-fitting into the insertion holes 1c and 2c, joining the bracket 2, and tightening the mounting bolt 4, a gear box is constructed.

Since the present invention has the above-described structure, it is possible to maintain the original positioning function without requiring extra seats or hole machining other than the mounting bolt seats, and furthermore, it is possible to maintain the original positioning function. This prevents it from moving in the axial direction and being pulled out to the outside, making it possible to maintain the quality and functionality of the product.

Figure 3 shows a structure in which workability is taken into consideration by providing a knock pin insertion hole 2C that also serves as a mounting bolt hole on the bracket 2 side, so that the mounting bolt 4 can be tightened after driving the knock pin from the outside. Same as above.

〔Effect of the invention〕

According to the positioning structure for maintaining frame accuracy in a gear box of the present invention, since the mounting bolts and dowel pins are arranged at the same location and concentrically, there is no need to provide an extra seat other than the mounting bolt seat. This makes it possible to prevent interference with the gear box, making it possible to make the gear box more compact and weigh more.

Furthermore, it is possible to prevent the dowel pin from moving in the axial direction and being pulled out due to vibrations during operation, thereby maintaining the quality and functionality of the product.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view showing an embodiment of the frame precision maintaining and positioning structure of the gear box of the present invention, and FIGS. 2 and 3 are partially cutaway side views showing an embodiment of the present invention. A detailed partial view, FIG. 4 is a partially cutaway side view showing a prior art gear box.

Claims (1)

[Claims] 1. In a structure in which a gear box is constructed by providing a concave spigot and a convex spigot at the joint of the casing and the bracket, and tightening the casing and bracket with a plurality of mounting bolts, the screw holes of the plurality of mounting bolts are provided. and a dowel pin insertion hole is provided concentrically with the bolt through hole and facing each other on the casing side and the bracket side,
By press-fitting a hollow knock pin with a through hole into which a mounting bolt can be inserted into the knock pin insertion hole, the frame precision positioning function can be maintained without providing an extra seat other than the mounting bolt seat, and the axis of the knock pin can be maintained. A gear box frame accuracy maintenance and positioning structure that is characterized by being able to prevent directional movement from falling out.