JPH02142918A - Coating structure of roller return passage in linear guide device and its manufacturing method - Google Patents

Abstract

PURPOSE:To form economically and efficiently a roller return passage with high accuracy without depending on the block construction and the broach processing by covering the inner wall of a through hole having the round section to the square shape with the plastic to form the roller return passage. CONSTITUTION:A through hole (lower hole) 10 having the round section is drilled at the predetermined position in the wall thickness of a wing 2b of the slider main frame 2. A drill having the diameter large than the length of the diagonal of a roller R is used in the drilling process. Firstly, the lower end side of the lower hole 10 is sealed, and the predetermined quantity of the plastic 11A such as the cold setting epoxy resin is flowed into the lower hole 10. A prism punch 15 on which the surface lubricant is coated is inserted into the lower hole 10 till it touch the lower end of the hole. The prism punch 15 has the section shape and the size as same as the square section shape and the size of a roller return passage 5. After the filled plastic 11A is hardened, the prism punch 15 is pulled out. Thereby, the plastic covering layer 11 of the inner surface of the lower hole 10 and the square-shaped through hole 12 are simply formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a coating structure for a roller return passage in a linear guide device in which the inner wall of the roller return passage is coated with plastic, and a method for manufacturing the same.

[Conventional technology]

The roller linear guide device is a linear guide device that uses rollers having a substantially square longitudinal section as rolling elements. A conventional roller linear guide device of this type is disclosed in, for example, Japanese Utility Model Application Publication No. 118021/1983.

As shown in FIG. 5, a slider 2 is movably axially straddled over an extended guide rail 1 having axial roller rolling grooves 3 on both sides. . A roller rolling groove 4 facing the roller rolling groove 3 of the guide rail is formed on the inner surface of the slider 2. Furthermore, a roller return passage 5 is formed parallel to the roller rolling groove 4. The roller rolling grooves 3, 4 and the roller return passage 5 are connected to each other by a curved path at the front and rear ends to form a roller circulation path. A large number of rollers R are inserted into this roller circulation path so as to be freely removable. Through the shifting of these rollers R, the slider 2 can be moved lightly back and forth on the guide rail l.

[Problem to be solved by the invention]

Incidentally, the roller return passage 5 has a rectangular cross section in accordance with the shape of the roller R. However, since it is not possible to easily drill a deep rectangular through hole, the roller return passage 5 is divided into two parts at the center in the above-mentioned conventional glue-Larlinear guide device, and each divided member has a groove. A method has been adopted in which a square roller return passage 5 is formed by processing the divided members and then joining these divided members together.

As a result, the number of parts increases and the structure of the product becomes complicated.

However, in order to form the roller return passage 5 without using such a dividing method, broaching may be considered.

However, broaching in this case has the following problems.

■ Prior to drilling the broach, it is necessary to drill a pilot hole for the broach, but this pilot hole must have a diameter smaller than the distance between the facing faces of the square holes.

That is, the pilot hole drill diameter is small. Therefore, the drill is easily bent, resulting in low machining efficiency and poor machining accuracy.

■ Broochier tools are very expensive and processing costs increase.

■ Harness from broaching accumulates in the corners of the square hole, making it difficult to completely remove it.

Therefore, the present invention has been made by focusing on the above-mentioned conventional problems, and its purpose is to utilize trill drilling, which is simple and easy to obtain with high precision, without using the dividing method or broaching. An object of the present invention is to form a square hole for a roller return passage in a linear guide device at low cost, efficiently (and with high precision).

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a movable idler on the guide rail, such as an extended guide rail having axial roller rolling grooves on both sides. A slide and a slider which are fitted and have a roller rolling groove on the side surface facing the roller rolling groove of the guide rail and a roller return passage parallel to this in the wall thickness, both of the roller rolling grooves and the roller return passage. A linear guide device comprising a large number of rollers rolling in a roller circulation path including a roller return path, wherein the inner wall of a through hole having a circular cross section is coated with plastic in a square shape. shall be.

The plastic coating can contain a solid lubricant.

Further, the method for manufacturing the roller return passage in the linear guide device of the present invention is to drill a through hole with a circular cross section larger than the diagonal length of the roller at the position where the roller return passage is to be formed, and pour a predetermined amount of plastic into the through hole. The space between the inner wall of the through hole and the prismatic surface is filled with plastic by inserting a prismatic column substantially in contact with the prismatic surface, and after the plastic hardens, the prismatic column is removed to form a roller return passage.

[Function] Since the structure of the roller return passage is such that the inner wall of the through hole with a circular cross section is covered with plastic in a square shape, the through hole with a circular cross section can be drilled with a large diameter drill. Drilling is easy and efficient. Furthermore, since a predetermined square hole can be formed by covering the inner wall of the through hole with plastic in a square shape, the conventional expensive and troublesome broaching process can be dispensed with, and there is no need for deburring work at all.

Further, there is no need to divide the slider to form a roller return passage, and the structure is simple and inexpensive.

Further, if the plastic coating layer contains a solid lubricant, the driving friction of the slider can be reduced.

〔Example〕

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

1 to 4 show one embodiment of the present invention. Note that the same reference numerals are given to the same or equivalent parts as in the prior art.

The main body 2A of the slider 2, which is movably and loosely fitted onto the guide rail 1, has a body structure rather than the conventional divided structure. A roller return passage 5 is provided within the thickness of the sleeve portion 2b having a U-shaped cross section. This roller return passage 5 is formed by covering the inner peripheral surface of a through hole 0 with a circular cross section with a plastic coating layer 11 and having a square through hole 12 in the center. The size of the rectangular through hole 12 is such that the roller R can pass through it easily. The plastic coating layer 11 may be made of thermosetting synthetic resin or thermoplastic synthetic resin as long as it is solidified at the operating temperature of the linear guide device. Further, the arrangement of the square through holes 12 may be arranged approximately symmetrically with the roller R in the roller rolling groove 3.4 as shown in the figure, but the arrangement is not limited to this, and for example, the roller shafts may be arranged perpendicularly. It is possible. Furthermore, the position of the roller return passage 5 is not limited to that shown in the drawings.
It can also be placed at other locations within the wall thickness of the sleeve portion 2b.

The method of manufacturing the roller return passage 5 will be explained below.

First, a through hole (preparatory hole) 10 having a circular cross section is bored at a predetermined position within the wall thickness of the sleeve portion 2b of the slider body 2A (FIG. 2). In this drilling process, a drill with a diameter larger than the diagonal length of the roller R is used.

That is, this drill diameter is much larger than the pilot hole drill diameter when broaching the roller return passage 5.
There are no problems such as bending the drill, and drilling can be performed with high efficiency.

Next, first, the lower end side of the pilot hole 10 is closed, and a predetermined amount of plastic IIA, such as room temperature curing epoxy resin, is poured into the pilot hole 10 from the upper opening (FIG. 3).

Thereafter, a prismatic bunch 15 coated with a mold release agent is inserted into the prepared hole 10 up to its lower end. This prismatic bunch 15 has the same cross-sectional shape and dimensions as the square cross-sectional shape and dimensions of the roller return passage 5. Further, a collar 16 is provided in accordance with the length L of the slider body 2A (that is, the length of the roller return passage 5), and a discharge port 17 for excess plastic IIA is formed in this collar. As a result, the pilot hole 1o and the prismatic bunch 15
The space between the cup is filled with plastic IIA, and the prismatic bunch 15 can be well positioned and held (FIG. 4).

Once the filled plastic IIA has hardened, the prismatic bunch 15 is pulled out.

In this way, the plastic coating layer 11 on the inner surface of the pilot hole 10 and the rectangular through hole 12 are easily formed.

According to this embodiment, there is no need to take the trouble to divide the slider 2 to form the roller return passage 5, and the structure is simplified.

In addition, there is no need for broaching, which is not easy to process narrow deep holes (and requires expensive tools, as well as difficult deburring work), which greatly contributes to cost reduction and improved production efficiency. be able to.

In addition, the system has the effect of alleviating noise problems, which have recently become subject to particularly strict regulations. That is, the slider main body 2A is a steel product. Therefore, the contact between the inner wall of the conventional roller return passage 5 and the roller R is a steel-to-steel contact.
Although there is a lot of noise when the slider 2 moves at high speed, in this embodiment the roller R comes into contact with the plastic coating layer 11, so the noise generation is significantly reduced.

Note that the plastic coating layer 11 is coated with graphite in advance.

By mixing a solid lubricant such as molybdenum disulfide, the sliding friction of the rollers R can be reduced, and the driving torque of the motor for driving the linear guide device can be reduced.

〔Effect of the invention〕

As explained above, according to the present invention, in the roller linear guide device, the roller return passage is formed by covering the inner wall of the through hole with a circular cross section in a square shape with plastic.

Therefore, it is possible to form the roller return passage inexpensively, efficiently, and with high accuracy without using a divided structure or blow preprocessing.

Further, if the plastic coating layer contains a solid lubricant, the effect of reducing the driving friction of the slider can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part of an embodiment of the present invention. Figures 2, 3, and 4 are partial cross-sectional views illustrating the manufacturing process of the device shown in Figure 1, respectively, and Figure 5 is a front view showing a partial cross-section of the structure of the roller return passage in a conventional roller linear guide device. It is a diagram. 1 is a guide rail, 2 is a slider, 3.4 is a ball rolling groove, 10 is a through hole (prepared hole) with a circular cross section, 11 is a plastic coating layer, 12 is a square through hole, and 15 is a prismatic punch.

Claims (3)

[Claims] (1) An extended guide rail with axial roller rolling grooves on both sides, and a roller that is movably loosely fitted onto the guide rail and faces the roller rolling groove of the guide rail. A linear slider comprising a slider having a groove on its side surface and a roller return passage parallel to the groove within its wall thickness, and a large number of rollers rolling in a roller circulation path including both of the roller rolling grooves and the roller return passage. A covering structure for a roller return passage in a linear guide apparatus, wherein the inner wall of a through hole of the roller return passage has a circular cross section and is covered with plastic in a rectangular shape. (2) A coating structure for a roller return passage in a linear guide device according to claim (1), wherein the plastic coating contains a solid lubricant. (3) Drilling a through hole with a circular cross section with a diameter larger than the diagonal length of the roller at the roller return passage forming position, pouring a predetermined amount of plastic, and inserting a prism approximately in contact with the through hole;
The roller in the linear guide device according to claim 1, wherein the space between the inner wall of the through hole and the prismatic surface is filled with plastic, and after the plastic solidifies, the prismatic is removed to form the roller return passage. Manufacturing method for return passage.