JPH06320472A - Shaft drive mechanism - Google Patents

Abstract

PURPOSE:To improve durability through prevention of wear of a shaft member and to form a shaft member by using a soft material, in a shaft drive mechanism comprising a square tubular shaft member and a housing through which the square tubular shaft member is axially movably inserted and which has a plurality of rollers movably supporting the shaft member. CONSTITUTION:A shaft drive mechanism 1 comprises a square tubular shaft member 21 and a housing 2 through which the shaft member 21 is axially movably inserted and which has a plurality of rollers 7, 7,... to movably support the shaft member 21. Thin steel sheets 24, 24,... are mounted on a contact surface with the roller of the shaft member 21.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel shaft drive mechanism. More specifically, a shaft drive mechanism comprising a square pipe-shaped shaft member and a housing provided with a plurality of rollers for movably supporting the shaft member while the shaft member is movably inserted in the axial direction of the shaft member. An object of the present invention is to provide a novel shaft drive mechanism capable of preventing wear of members and improving durability, and also capable of forming the shaft member with an inexpensive soft material.

[0002]

2. Description of the Related Art FIG. 6 shows a two-axis drive mechanism a which is formed by combining two conventional axis drive mechanisms b at right angles.

B1 is a first uniaxial drive section, and b2 is a second uniaxial drive section.
The shaft drive unit includes a shaft member c each having a rectangular pipe shape, and a housing d that supports the shaft member c movably in the axial direction.

Rolling supporting portions f provided with a set of eight rollers e, e, ... Are provided in the housing d at two positions separated from each other in the axial direction, and four outer side surfaces of the shaft member c are provided. Two rollers e in each rolling support part f,
e rotatably abuts and supports the shaft member c.

Incidentally, such rolling support parts f, f are provided on one inner surface of the housing d at two positions which are axially separated from each other.

Thus, the shaft member c is sent by a drive mechanism (not shown), and the shaft member c moves relatively to the housing d.

The outer surfaces of d are connected so that the housings d and d of the uniaxial drive mechanisms b1 and b2 are orthogonal to each other to form a biaxial drive mechanism a.

By the way, such a shaft drive mechanism b has the advantages that it has a simple structure, and that when a square pipe is used for the shaft member c, it can be manufactured at low cost and can be made lightweight. .

However, in such a shaft drive mechanism b, if a square pipe manufactured by a die-drawing method such as aluminum is used for the shaft member c, it is cheaper and lighter, but the material is relatively large. Soft, roller e,
In the extreme case, that is, the shaft member c
When a high load is applied to the rollers e, e, ... Is transmitted to the rollers e, e ,. Therefore, in such a case, the movement of the shaft member c with respect to the housing d becomes heavy, and the shaft member c cannot be smoothly driven.

Further, the shaft member c is made of a relatively soft material.
Since the rollers e, e, ... Repetitively run on the upper surface, the contact surface between the shaft member c and the rollers e, e ,.
There is also a problem that wear of the tracks on which e, ...

Therefore, in order to solve the above problems of the shaft drive mechanism b, a shaft drive mechanism h as shown in FIG. 7 can be considered.

Incidentally, g is a biaxial drive mechanism formed by combining two of the above-mentioned axial drive mechanisms h at right angles.

Reference numeral h1 is a first uniaxial drive section, and h2 is a second uniaxial drive section.

Each of the uniaxial drive parts h1 and h2 includes a shaft member i in the shape of a square pipe, and a housing j that movably supports the shaft member i in its axial direction.

Rail members k, k made of steel extending in the axial direction are provided on the two outer surfaces of the shaft member i located on opposite sides of the shaft member i.
Is fixed.

Reference numerals l and l denote rolling support portions provided on the inner surface of the housing j at positions opposed to the rail members k and k of the shaft member i, and are provided with rollers m and m inclined at about 45 degrees, respectively. The rollers m, m are in rolling contact with the inclined surfaces n, n of the rail members k, k.

It should be noted that such rolling support portions 1, 1 are provided on one inner surface of the housing j at two locations which are axially separated from each other.

Thus, the shaft member i is sent by a drive mechanism (not shown), and the shaft member i moves relative to the housing j.

In such a shaft drive mechanism h, the rollers m, m have a structure in which the rollers m, m travel on rail members k, k fixed to the shaft member i. As described above, there are problems that the shaft drive mechanism b has, that is, the sinking phenomenon of the rollers m, m, ... And the wear of the contact surface of the shaft member i with the rollers m, m ,. The shaft member i can be driven lightly without generating
It has the advantage that the durability is also good.

[0020]

However, in the shaft drive mechanism h described above, if even one of the rollers m, m, ... Floats from the rail member k, the shaft member i will move. There is a problem that meandering occurs, which causes so-called backlash, and further, since rail members k, k are required as separate members, the cost is high and the shaft drive mechanism cannot be manufactured at low cost. Moreover, the weight of the shaft member also increases, and it is difficult to reduce the weight.

[0021]

In order to solve the above-mentioned problems, the shaft drive mechanism of the present invention has a shaft member in the shape of a square pipe and a shaft member into which the shaft member is movably inserted in its axial direction. A shaft drive mechanism comprising a housing provided with a plurality of rollers for movably supporting members, wherein a thin steel plate is attached to a contact surface of the shaft member with the rollers.

[0022]

Therefore, in the shaft drive mechanism of the present invention, since the shaft member is formed of the thin steel plate attached to the surface where the square pipe and the roller come into contact with each other, the shaft drive mechanism can be reduced in weight and further improved in height. Since a steel plate having a low hardness, such as a leaf spring or a square pipe material, can be easily obtained at a low price, a shaft drive mechanism having high durability can be manufactured at a low cost.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the shaft drive mechanism of the present invention will be described below with reference to the embodiments shown in the accompanying drawings.

Reference numeral 1 denotes a shaft drive mechanism, which comprises a shaft member and a housing that supports the shaft member so as to be movable in its axial direction.

Reference numeral 2 denotes a housing, which is formed of a metal plate in the shape of a short rectangular tube having a substantially square cross section, and 3a, 3b, 3c and 3d are four side wall portions of the housing 2, respectively.

Reference numerals 4 and 4 denote end plates fixed to both ends of the rectangular tube, and the end plates 4 and 4 are formed with substantially square insertion holes 5 and 5 having a size into which a shaft member described later is inserted. Has been done.

Rolling support portions 6, 6 are provided at positions near both ends inside the housing 2, respectively. 2
Since the two rolling support portions 6, 6 have the same structure, only one of them will be described in detail.

The rolling support portion 6 is provided with eight rollers 7, 7 ,. .., and there are a total of 4 sets of 2 rollers, of which 2
The set is made up of fixed rollers 7a, 7a, ... And the remaining two sets are made up of movable rollers 7b, 7b.

8 and 8 are attached to the housing 2 at the positions in contact with the end plate 4 in the housing 2 and at the positions in contact with the inner surfaces of the portions of the side wall portion 3c located on the opposite side to the side wall portion 3a in the width direction. It is a fixed roller support block.

As shown in FIG. 2, each roller support block 8 has bolts 10 and 1 which are inserted into the side wall portion 3c from the outside.
0 is screwed onto the surface in contact with the inner surface of the side wall portion 3c, and
Other bolts 10 and 10 that are inserted through the end plate 4 from the outside are screwed into the surface of the end plate 4 that is in contact with the inner surface of the end plate 4, and are thereby fixed at the above-mentioned positions in the housing 2.

The two roller support blocks 8, 8
Fixed rollers 7a and 7a are rotatably supported by roller support shafts 9 and 9 projecting from opposite sides of
In this state, a part of the fixed rollers 7a, 7a is projected from the end portions of the roller support blocks 8, 8 on the side opposite to the side wall portion 3c toward the baffle center side.

Reference numeral 11 denotes a roller support block fixed to the inner surface of the side wall portion 3d at a position in contact with the end plate 4, and has a length approximately twice that of the roller support block 8.

The roller support block 11 is fixed to the housing 2 while being in contact with the side wall portion 3b and the end plate 4.

That is, the bolts 10 and 10 inserted from the outside at positions separated from each other in the width direction of the side wall portion 3d are screwed onto the surface of the roller support block 11 which is in contact with the inner surface of the side wall portion 3d, and further, the end plate 4 is provided. Bolts 10 and 10 inserted from the outside at positions separated in the width direction are used for the end plate 4 of the roller support block 11.
The roller support block 11 is fixed to a predetermined position in the housing 2 by being screwed into a surface in contact with the inner surface.

The fixed rollers 7a and 7a are rotatably supported by the roller support shafts 12 and 12 projecting from the end surfaces of the side walls 3d of the roller support block 11 which are located on the opposite sides in the width direction. In this state, a part of the fixed rollers 7a, 7a is projected from the end of the roller support block 11 on the side opposite to the side wall 3d toward the center of the baffle.

Reference numeral 13 is a roller support block fixed to the end plate 4 at a position close to the inner surface of the side wall portion 3a, and 14,
Reference numeral 14 is a roller support shaft for supporting the rollers 7, 7 protruding from the end surfaces of the side wall portion 3a of the roller support block 13 which are located on opposite sides in the width direction.

The length of the roller support block 13 in the width direction of the side wall portion 3a is substantially the same as that of the roller support block 11, and the thickness in the direction perpendicular to the side wall portion 3a is that of the roller support block 11. It is made smaller.

Further, the roller support block 13 is provided with the end plate 4
Bolts 10 and 10 inserted from the outside through long holes formed at positions spaced apart from each other in the width direction of the roller support block 13 are screwed onto the surface of the roller support block 13 in contact with the inner surface of the end plate 4, whereby the roller support block 13 is formed. Are fixed in place in the housing 2.

Reference numeral 15 denotes a support plate fixed to a position facing the roller support block 13 on the inner surface of the side wall portion 3a and formed of a metal plate, and fixed to the inner surface of the side wall portion 3 by welding or the like.

The support plate 15 is formed with screw holes 16, 16 at positions near both ends thereof.
Reference numerals 6 and 16 are formed at positions corresponding to the bolt insertion holes formed in the side wall portion 3a.

Reference numerals 17 and 17 denote adjusting bolts. These adjusting bolts 17 and 17 are inserted into the side wall portion 3a from the outside,
And, by being screwed into the screw holes 16 of the support plate 15,
The tip thereof is in contact with the surface of the roller support block 13 facing the inner surface of the side wall portion 3a.

Reference numerals 18 and 18 denote lock nuts, which are screwed into the portions of the adjusting bolts 17 and 17 projecting to the outside of the side wall portion 3a to fix the positions of the adjusting bolts 17 and 17.

The movable rollers 7b, 7b are rotatably supported by the roller support shafts 14, 14 of the roller support block 13, respectively. In this state, the movable rollers 7b, 7b are rotatably supported.
Parts b and 7b are adapted to project from the end of the roller support block 13 on the side opposite to the side wall 3a toward the center of the bladder.

Reference numeral 19 denotes a roller support block fixed to the end plate 4 at a position close to the inner surface of the side wall portion 3b, and the roller support block 19 is formed to have substantially the same size as the roller support block 13.

The roller support block 19 is provided on the end plate 4
Bolts 10 and 10 inserted from the outside through long holes formed at positions spaced apart from each other in the width direction are screwed onto the surface of the roller support block 19 in contact with the inner surface of the end plate 4, whereby the roller support block 19 is It is fixed in place in the housing 2.

A support plate 15 similar to the above-mentioned support plate 15 is also fixed to a position facing the roller support block 19 on the inner surface of the side wall portion 3b.

Then, the adjusting bolts 17, 17 are attached to the side surface portion 3
b is inserted from the outside, and the screw hole 1 of the support plate 15 is
6 and 16 are screwed together, and the tips thereof are brought into contact with the surface of the roller support block 19 facing the inner surface of the side wall portion 3b,
Lock nuts 18, 18 are screwed into the protruding portions of the adjusting bolts 17, 17 to the outside of the side wall portion 3b to fix the positions of these adjusting bolts 17, 17.

Further, movable rollers 7b and 7b are rotatably supported by roller support shafts 20 and 20 projecting from end surfaces located on opposite sides in the width direction of the side wall portion 3b of the roller support block 19, respectively. In this state, a part of the movable rollers 7b, 7b is projected from the end of the roller support block 19 on the side opposite to the side wall 3b toward the center of the baffle.

Reference numeral 21 denotes a shaft member, which is made of, for example, aluminum and is formed into a rectangular tube shape by a die-drawing method, and has four peripheral surfaces 22, 22, ... .. are formed in two rows at regular positions in the longitudinal direction at regular intervals.

Numerals 24, 24, ... Are rail plates having substantially the same length as the shaft member 21 and a width approximately twice the axial width of the rollers 7, 7 ,. For example, it is made of a leaf spring material, and holes 25, 25, ... Corresponding to the holes 23, 23 ,. These holes 23, 23,
, And holes 25, 25, ... together with rivets 26, 2
Two pieces are fixed to the outer peripheral surface 22 of the shaft member 21 on the contact surface with the rollers 7, 7 ,.

Therefore, the shaft member 21 is inserted into the housing 2 through the insertion holes 5 and 5 formed in the end plates 4 and 4, and the rolling support portions 6 at two positions in the housing 2 are
6, each of which is supported by eight rollers 7, 7, ...

That is, in each rolling support portion 6, two rollers 7, 7, ... Are respectively rotatably contacted with the four outer peripheral surfaces 22, 22 ,. Not driven by the drive unit in the axial direction. And
At this time, track plates 24, 24, ... Are fixed to the contact surfaces of the outer peripheral surfaces 22 with the rollers 7, 7 ,.
The rollers 7, 7, ...
4, 24, ... and rolling on the track plates 24, 24, ..., so that the sinking phenomenon does not occur.
Rollers 7, 7 of the shaft member 21 made of aluminum and soft,
Wear due to ... Is prevented.

By the way, in order to uniformly contact all the rollers 7, 7, ... With the shaft member 21 in each rolling support portion 6, as described above, the movable rollers 7b are opposed to the fixed rollers 7a, 7a. , 7b are arranged.

That is, two fixed rollers 7a, 7 are provided on each of the two adjacent outer peripheral surfaces 22, 22 of the shaft member 21.
Although a is in contact with the outer peripheral surfaces 22 and 22, two movable rollers 7b and 7b are respectively in contact with the two outer peripheral surfaces 22 and 22 located on the opposite side of the outer peripheral surfaces 22 and 22, respectively.

Therefore, the fixed rollers 7a facing each other,
7a and the movable rollers 7b, 7b become too larger than the distance between the outer peripheral surfaces 22, 22 located on the opposite sides of the shaft member 21, and the fixed rollers 7a, 7a or the movable rollers 7
When a gap is formed between the movable rollers 7b and 7b, or when the gap is too narrow, the roller support block 13 or 19 supporting the movable rollers 7b and 7b.
Bolts 10 and 10 and lock nuts 18 and 1 screwed together
After loosening 8, adjust bolts 17 and 17 to support plate 15
The roller supporting block 1 is screwed in or unscrewed from the screw holes 16 of the roller supporting block 1 and the tip thereof is advanced or retracted.
The distance is adjusted by pressing 3 or 19 toward the roller support block 8, 8 or 11 facing it or vice versa. By making such adjustments, the rollers 7 and 7 are attached to the four outer peripheral surfaces 22 and 2 of the shaft member 21.
2, ... all, that is, these outer peripheral surfaces 22, 22, ...
It is possible to make a contact with the rail plates 24, 24 fixed to the ·, while maintaining an appropriate contact pressure.

In the above embodiment, the rail plates 24, 24, ... Are provided on the four outer peripheral surfaces 22, 22, ... Of the shaft member 21.
······································································ For example, as shown in FIG. 4, the outer peripheral surfaces 22, 22, ...
Using the rail plates 27, 27, ... Having a width substantially the same as the width of the holes 28, holes 28 are formed in the longitudinal direction in a row at regular intervals at a substantially central portion in the width direction of each outer peripheral surface 22, 28, ... and rail plates 27, 27, ..
8, 28 ... Holes 29, 29, ...
.. and rivets 26, 26, like the rail plate 24,
.. may be fixed to the shaft member 21 and the entire outer peripheral surface 22 may be covered with one track plate 27.

Further, the outer peripheral surfaces 22, 22, ... Of the shaft member 21.
.. wear of the contact surfaces with the rollers 7, 7, ...
Since it is particularly intense at the upper and lower surfaces 2 as shown in FIG.
The rail plates 24, 24, ... May be attached only to the 2a and 22a.

[0058]

As is apparent from the above description, in the shaft drive mechanism of the present invention, the shaft member having a square pipe shape and the shaft member are movably inserted in the axial direction and the shaft member is movable. A shaft drive mechanism comprising a housing provided with a plurality of rollers supported on a roller, characterized in that a thin steel plate is attached to a contact surface of the shaft member with the roller.

Therefore, in the shaft drive mechanism of the present invention, the shaft member is formed by the thin steel plate attached to the surface where the square pipe and the roller come into contact with each other. Steel plates with low hardness, such as leaf springs and square pipe materials, are cheap and easily available,
A shaft drive mechanism with high durability can be manufactured at low cost.

Note that the specific structures and shapes shown in the above embodiments are merely examples of the implementation of the present invention, and the technical scope of the present invention is limited by these. Not interpreted.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a shaft drive mechanism of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along the line II-II of FIG.

FIG. 3 is an enlarged perspective view showing a part of a shaft member.

FIG. 4 is a sectional view of an essential part showing a modified example.

FIG. 5 is a cross-sectional view of a main part showing another modification.

FIG. 6 is a side view showing an example of a conventional shaft drive mechanism with a part cut away.

FIG. 7 is a side view showing a comparative example with a part cut away.

[Explanation of symbols]

 1 Shaft drive mechanism 2 Housing 7 Roller 21 Shaft member 24 Thin steel plate (rail plate) 27 Thin steel plate (rail plate)

Claims (3)

[Claims] 1. A shaft drive mechanism comprising a square pipe-shaped shaft member and a housing provided with a plurality of rollers through which the shaft member is movably inserted in the axial direction and which movably supports the shaft member. A shaft drive mechanism, wherein a thin steel plate is attached to a contact surface of the shaft member with the roller. 2. The shaft drive mechanism according to claim 1, wherein the square pipe-shaped shaft member is made of aluminum. 3. The shaft drive mechanism according to claim 1, wherein a thin steel plate is attached to a surface of the shaft member that is in contact with the roller and receives a load.