JP2660731B2 - Absolute type rod with bit pattern - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an absolute-type bit-patterned rod.

[Conventional technology]

2. Description of the Related Art Conventionally, for a pressure cylinder that expands and contracts a rod by obtaining air pressure or oil pressure, the following configuration is known for measuring the amount of expansion and contraction of the rod.

(1) Rod: Incremental type information (for example, 1,
Generally, a configuration in which simple information (0, 1, 0... Arranged) is patterned on the rod surface.

(2) Manufacturing method: desired incremental shape information is determined in advance, a concave portion is locally formed on the rod surface by machining or the like according to this pattern, and then a metal or the like having different electromagnetic characteristics is formed in the concave portion. And finally finishing the entire surface to produce the rod of the above (1).

(3) Position detecting device: A position detecting device is provided with the same number of position detecting sensors as the number of rows of the incremental type information (for example, on the head of a pressure cylinder, etc.) so that its sensor surface is close to and facing the incremental type information on the rod surface. In general, a position detecting device configured to detect the incremental type information on the surface of the device is generally used.

[Problems to be solved by the invention]

However, the conventional configuration has the following disadvantages. In order to detect the relative position between the rod and the position detection sensor in the position detection device, the relative initial position between the rod and the position detection sensor is stored in advance by a CPU or the like, or the rod is returned to the origin every time measurement is performed. Thus, since the number of the incremental type information must be counted from the initial position or the origin, the detection is slow and redundant, and there is a surface unsuitable for high-speed detection. Further, there is a disadvantage that the number of the incremental type information is erroneously counted when the rod expands and contracts at a high speed or under a high load in different directions and sizes. Further, in the rod manufacturing method, since the rod surface is once cut into a concave shape, an unexpected situation may occur unless the rod has sufficient strength in advance.

An object of the present invention is to provide an absolute-type bit-patterned rod that can measure the relative position between a rod and a position detection sensor at high speed and with high accuracy.

[Means for solving the problem]

In order to achieve the above object, the rod with a bit pattern according to the present invention is a pressure cylinder rod, which has a thermosetting layer on the surface of the rod and the electromagnetic properties of the thermosetting layer by local heating in the thermosetting layer. It is characterized in that bit patterns having different electromagnetic characteristics are formed for each stroke so that the stroke position can be determined.

[Action]

According to the above configuration, since the rod with the absolute type bit pattern according to the present invention has the absolute type bit pattern on the rod surface, the expansion and contraction amount of the rod is related to the magnitude of the load, the load vibration, the expansion and contraction speed of the rod, and the like. And can always be detected with high accuracy. Moreover, since the rod surface is thermoset, the strength required for the rod of the pressure cylinder is sufficiently ensured. Details are as follows. The absolute type bit pattern is only made to have electromagnetic characteristics different from the electromagnetic characteristics of the thermosetting layer by local heating. In other words, the absolute type bit pattern
Since the thermosetting layers are both based on heat treatment, there is almost no strong boundary between them. Therefore, the strength required for the rod of the pressure cylinder is sufficiently ensured. That is, according to the above configuration, an absolute type bit pattern rod having high strength and high accuracy in detecting the amount of expansion and contraction is obtained.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, the surface of the rod 2 is patterned with 8-bit absolute type information 3. On the other hand, the same number (eight) of position detection sensors 6 as the number of bits of the absolute type information 3 are provided on the head 4 of the cylinder 1.
Is provided. Reference numeral 7 denotes wiring for outputting the detected absolute type information 3. 5 is a seal.

FIG. 2 shows a second embodiment, and FIG. 2 (a) is a partially enlarged view of the rod 2. FIG. On the surface of the rod 2, 4-bit absolute type information 3 is patterned. Specifically, assuming that 1 to 4 digits of 4 bits are a to d, the absolute type information 3 at the top of the figure is "a = b = c = d = 0, as shown in FIGS. ”, That is, the binary number“ 0000 ”, which means the decimal number“ 0 ”. The absolute type information 3 in the second row is “a = b = c = 0, d =
1 ", that is, binary" 0001 "and decimal" 1 "
Means Similarly, the absolute type information 3 is patterned to “a = b = c = d = 1”, that is, to “1111” in binary (that is, “15” in decimal).
In FIG. 1, if the rod 2 is of the second embodiment, four position detecting sensors 6, the rod 2 expands and contracts, the head 4 is fixed, and if the length between one memory is 10 mm, the length is up to 150 mm. If it is a position, whether it is the initial position or the change position of the working path, the position detection sensor 6 can detect 1 to 15 (that is, it can detect the amount of expansion and contraction of the rod 2). The rod 2 is an absolute type information 3 to be patterned on the surface.
May be not only information arranged in order as described above, but also encrypted absolute type information.

Next, although not shown, a method of manufacturing the rod 2 will be described.
In the step of locally heating the surface of the rod 2 to form a bit pattern, laser or EBW (Ele
In the process of performing surface hardening on the surface of the rod 2, the surface hardening includes heat treatment such as quenching, carburizing, nitriding, and hard plating such as chrome plating. Etc.

According to the above embodiment, the following effects can be obtained. Third
As shown in the figure, the detection signal 8 from each position detection sensor 6
(The output of FIG. 7A is shown for each detection position), and by providing a threshold 9 by a comparator, the detection signal 8 can be output as a pulse 10 as shown in FIG. . Since the pulse 10 is a digital signal, it can be easily input to the CPU, thereby enabling high-speed detection. Further, since the absolute type information 3 is detected, the position is detected with high accuracy.

On the other hand, in the method of manufacturing the rod with the absolute bit pattern, any one of the two steps of local heating and surface hardening may be performed first. Moreover, since there are only two steps and the processing contents are various, a rod with an absolute type bit pattern can be easily manufactured.

〔The invention's effect〕

As described above, according to the rod with the absolute type bit pattern according to the present invention, since the rod type has the absolute type bit pattern, the amount of expansion and contraction of the rod is related to the magnitude of the load, the load vibration, the expansion and contraction speed of the rod, and the like. And can always be detected with high accuracy. Moreover, since the rod surface is thermoset, the strength required for the rod of the pressure cylinder is sufficiently ensured. Details are as follows.
The absolute type bit pattern is only made to have electromagnetic characteristics different from the electromagnetic characteristics of the thermosetting layer by local heating. That is, since both the absolute type bit pattern and the thermosetting layer are based on heat treatment, there is almost no strong boundary between them. Therefore, the strength required for the rod of the pressure cylinder is sufficiently ensured.
That is, according to the invention of the present application, an absolute-type bit pattern rod having high strength and high accuracy in detecting the amount of expansion and contraction is obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of a cylinder having a rod with an absolute type bit pattern according to a first embodiment. Second
FIG. 2 is a perspective view of a rod with an absolute type bit pattern according to a second embodiment, in which (a) shows a rod and a dot pattern, and (b) shows a bit pattern meaning 2
FIG. 3C is a diagram illustrating a decimal number, and FIG. 3C is a diagram illustrating a decimal number represented by a bit pattern. 3A and 3B are diagrams for explaining the effect of the position detecting device, wherein FIG. 3A is a graph showing the relationship between the detection output and the position, and FIG. 3B is a graph showing the relationship between the pulse output and the position. 1 ... Cylinder 2 ... Rod 3 ... Absolute type information 4 ... Head 5 ... Seal 6 ... Position detection sensor 7 ... Wiring a, b, c, d ... Absolute type information

Claims (1)

(57) [Claims] In a rod of a pressure cylinder, a thermosetting layer is provided on the surface of the rod, and a bit pattern having electromagnetic characteristics different from the electromagnetic characteristics of the thermosetting layer due to local heating is applied to the thermosetting layer for each stroke. A rod with an absolute type bit pattern, wherein the stroke position is formed so as to be distinguishable.