JP7568901B2 - Raceway surface grinding machine - Google Patents

Description

The present invention relates to a raceway grinding machine that grinds a workpiece to form the raceway surface of a rolling element.

There is a known grinding machine that uses a grinding wheel or the like to grind a workpiece to form a rail track surface or the like on the workpiece (for example, Patent Document 1). Patent Document 1 discloses a multi-purpose grinding machine that manufactures linear guide rails by grinding a workpiece.

This composite grinding machine includes a work table on which a workpiece is placed, a gate-type column, a first grinding means having a pair of formed grinding wheels, and a second grinding means having one formed grinding wheel. The work table is provided on a long base and is a table that can be moved back and forth in the left and right directions on the long base by a driving means. The gate-type column has a pair of columns that stand across the long base from front to back, and a beam that is provided horizontally between the pair of columns.

The pair of formed grinding wheels of the first grinding means are supported by a grinding wheel shaft that is movable left and right and vertically movable relative to a cross rail provided on the left front surface of the gantry column. The single formed grinding wheel of the second grinding means is supported by a grinding wheel shaft that is movable back and forth and vertically movable relative to a cross rail provided on the rear surface of the gantry column.

In this composite grinding machine, a workpiece is placed on the worktable, and while the worktable is moved, both sides of the workpiece are ground with a pair of formed grinding wheels of the first grinding means, and at the same time, the top of the workpiece is ground with a single formed grinding wheel of the second grinding means. Patent Document 1 claims that because the top and both sides of the workpiece can be ground simultaneously, the grinding time for the workpiece can be shortened.

JP 2013-141734 A

However, the multi-purpose grinding machine in Patent Document 1 merely shortens the grinding time of the workpiece, and there is no description of a method for measuring the dimensions of the workpiece. Conventionally, workers have typically used a width gauge or similar to manually measure the distance of the grooves in the rail or block, and then repeatedly grind the workpiece to the specified dimensions. When considering automating this process, for example, simply adding a measuring device that automatically measures the dimensions of the workpiece to the multi-purpose grinding machine makes it difficult to accurately measure the dimensions of the workpiece due to dimensional deviations caused by thermal expansion associated with changes in the workpiece temperature during grinding, and grinding powder adhering to the workpiece.

In view of these problems, the present invention aims to provide a raceway grinding machine that can measure the dimensions of a workpiece with high accuracy and perform grinding with high dimensional accuracy.

To solve the above problems, a typical configuration of the raceway surface grinding machine according to the present invention includes a grinding section that grinds the workpiece to form the raceway surface of the rolling elements on the workpiece, a measuring machine that measures the dimensions of the workpiece, and a master workpiece that is installed near the machining position of the workpiece, and the measuring machine measures the dimensions of the workpiece after measuring the master work and calibrating the measuring machine.

In the above configuration, a master work is placed near the processing position of the workpiece to be ground by the grinding unit. The master work has an ideal shape for the workpiece after grinding, and by placing it near the processing position of the workpiece, it is in an environment (mainly a temperature environment) similar to that of the workpiece. Then, before measuring the dimensions of the workpiece, the measuring machine is calibrated by measuring the master work in an environment similar to that of the workpiece, and measures the dimensions of the workpiece after calibration, i.e., in a state where the reliability of the measurement is increased. Therefore, with the raceway surface grinding machine of the above configuration, it is possible to accurately measure the dimensions of the workpiece and perform grinding with high dimensional accuracy.

The above-mentioned raceway grinding machine further includes a mounting jig for mounting the master workpiece, and it is preferable that the mounting jig circulates coolant for cleaning the workpiece.

In this way, by circulating the coolant used to clean the workpiece through the mounting jig for the master work, the temperature of the master workpiece can be stabilized while bringing the temperature of the workpiece closer to that of the master work (reducing the temperature difference). This allows the master work to be placed in an environment closer to that of the workpiece, thereby further improving the reliability of measurements using a calibrated measuring instrument.

After grinding the workpiece with the grinding section of the above-mentioned raceway grinding machine, it is recommended that the workpiece be washed again with coolant before the dimensions of the workpiece are measured with the measuring machine.

Coolant is supplied during grinding, but the workpiece is also washed with coolant before the dimensions of the workpiece after grinding are measured with a measuring machine. This ensures that grinding powder adhering to the workpiece is almost always removed, allowing the dimensions of the workpiece to be accurately measured with the measuring machine. In addition, the workpiece is washed again with coolant and further cooled, reducing dimensional deviations due to the thermal expansion of the workpiece.

The above measuring machine has a measuring probe that is pressed against the workpiece and the master workpiece, and the raceway grinding machine preferably cleans the workpiece, master workpiece and measuring probe with air blower before measuring the workpiece and master workpiece with the measuring machine.

This allows grinding dust adhering to the workpiece, master workpiece, and measuring instrument's probe to be removed by air blowing, enabling the measuring instrument to accurately measure the workpiece's dimensions.

The above-mentioned raceway grinding machine is divided into a machining chamber for machining the workpiece, a cleaning chamber for cleaning the measuring element, and a master measurement chamber in which the master workpiece is installed. It is preferable that the partitions between the chambers through which the measuring machine enters and exits are provided with shutters.

As a result, grinding dust generated in the machining chamber when the workpiece is machined is blocked by the shutter and does not enter the cleaning chamber or master measurement chamber from the machining chamber. This prevents grinding dust from adhering to the measuring instrument's probe or the master workpiece, preventing measurement errors caused by grinding dust.

The present invention provides a raceway grinding machine that can measure the dimensions of a workpiece with high accuracy and perform grinding with high dimensional accuracy.

FIG. 2 is a diagram illustrating a raceway surface grinding machine according to an embodiment of the present invention. 2 is a diagram illustrating a measuring machine of the grinding apparatus of FIG. 1 and its surrounding structure. 3A and its surrounding structure; FIG. 2 is a flowchart showing the operation of the grinding device of FIG. 1 . 5A to 5C are diagrams illustrating the state of a grinding apparatus performing each operation of FIG. 4;

The preferred embodiment of the present invention will be described in detail below with reference to the attached drawings. The dimensions, materials, and other specific values shown in the embodiment are merely examples to facilitate understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements that have substantially the same function and configuration are given the same reference numerals to avoid duplicated explanations, and elements that are not directly related to the present invention are not illustrated.

Figure 1 illustrates an example of a raceway grinding machine (hereinafter, grinding machine 100) according to an embodiment of the present invention. Figure 1(a) illustrates the entire grinding machine 100. The grinding machine 100 is a device that automatically measures the dimensions of a workpiece 102, which is a workpiece, and grinds the workpiece 102, and includes a table 104, a column 106, a grinding machine 108, a measuring machine 110, and a master workpiece 112. Figures 1(b) and 1(c) respectively show the grinding machine 108 side and the measuring machine 110 side of the grinding machine 100 in Figure 1(a).

The table 104 is mounted on a base 114 and is configured to be movable on the base 114 in the direction of arrow A shown in FIG. 1(a), with the workpiece 102 attached to its upper portion. The column 106 is mounted on the base 114 and formed in a gate shape as shown in FIG. 1(b) and FIG. 1(c), and is positioned so as to surround the workpiece 102 and table 104 from above.

The grinding machine 108 is installed on the front side of the gate-shaped column 106 as shown in FIG. 1(b) and has a pair of grinding wheels 116, 118. The grinding machine 108 grinds the workpiece 102 attached to the moving table 104 with the pair of grinding wheels 116, 118 to form a track surface for the rolling elements (e.g., balls) on the rails or blocks of the workpiece 102. The measuring machine 110 is installed on the rear side of the gate-shaped column 106 as shown in FIG. 1(c) and measures the dimensions of the workpiece 102 and the master workpiece 112.

The master work 112 has an ideal shape for the work 102 after grinding, and is installed in a master measurement room (measurement room 120). In the measurement room 120, the dimensions of the master work 112 are measured by a measuring machine 110, and the master work 112 is cleaned with an air blower (described later). As shown in FIG. 1(c), the measurement room 120 is installed near the processing room (grinding room 122) where the work 102 is ground by the grinding machine 108. Therefore, the master work 112 is installed near the processing position of the work 102, and is in an environment (mainly a temperature environment) similar to that of the work 102.

Figure 2 illustrates an example of the measuring machine 110 of the grinding device 100 in Figure 1 and its surrounding structure. Figure 2(a) is an enlarged view of a portion of the grinding device 100 in Figure 1(c) in further detail. Figure 2(b) is an enlarged view of a portion of Figure 2(a).

As shown in FIG. 2(a), the grinding device 100 is divided by a measuring chamber 120, a grinding chamber 122, and a cleaning chamber 124 adjacent to the measuring chamber 120. The measuring chamber 120 and the cleaning chamber 124 are divided by partitions 126, 128, 130, and a top surface 140. The top surface 140 is also one of the partitions.

As shown in FIG. 2(b), the measuring machine 110 has a pair of arms 132, 134 and a pair of probes 136, 138 supported by the arms 132, 134. When measuring the dimensions of the workpiece 102 and the master workpiece 112, the probes 136, 138 are pressed against the workpiece 102 and the master workpiece 112 by the arms 132, 134. FIG. 2(a) illustrates a state in which the arms 132, 134 press the probes 136, 138 against the workpiece 102 to measure the dimensions of the workpiece 102.

The measuring machine 110 is configured to be movable vertically and horizontally with respect to the column 106, as shown by arrows B and C in FIG. 2(a). In addition, the top surfaces 140 of the cleaning chamber 124 and the measuring chamber 120 are provided with shutters 142 that can be opened and closed freely. Therefore, the measuring machine 110 can enter the cleaning chamber 124 or the measuring chamber 120 by rising from a state where it has entered the grinding chamber 122 shown in FIG. 2(a), moving further horizontally, waiting above the cleaning chamber 124 or the measuring chamber 120, and descending when the shutter 142 opens.

The measuring instrument 110 further has a pair of air blow nozzles 144, 146 as shown in FIG. 2(b). The air blow nozzles 144, 146 are directed toward the probes 136, 138 supported by the arms 132, 134 and their surroundings, and clean the probes 136, 138, the workpiece 102, and the master workpiece 112 with air blow. The probes 136, 138 are cleaned in the cleaning chamber 124.

The grinding device 100 further includes a pair of air blow nozzles 148, 150 and a pair of coolant cleaning nozzles 152, 154 in the grinding chamber 122, and an attachment jig 156 for attaching the master workpiece 112. The air blow nozzles 148, 150 are directed toward the workpiece 102 and clean the workpiece 102 with air blow. The coolant cleaning nozzles 152, 154 are directed toward the workpiece 102 and clean the workpiece 102 with coolant. The attachment jig 156 circulates coolant for cleaning the workpiece 102 (see FIG. 3). The cleaning chamber 124 is also provided with an air blow nozzle 151 and a coolant cleaning nozzle 155 for cleaning the gauges 136, 138.

Figure 3 is a diagram illustrating the structure of the mounting jig 156 and its surroundings in Figure 2(a). Figure 3(a) is a diagram illustrating the internal structure of the mounting jig 156 and its surroundings. Figure 3(b) is a diagram illustrating the master work 112 and mounting jig 156 in Figure 3(a) as viewed from below.

The mounting jig 156 is fixed by bolts or the like to a base 158 installed in the measurement chamber 120. Inside the base 158, a flow path 160 is formed that extends in the vertical direction as shown in FIG. 3(a). Coolant flows through the flow path 160 toward the mounting jig 156 as shown by arrow D in FIG. 3(a).

In addition, a flow path 162 is formed inside the mounting jig 156, as shown in FIG. 3(a). The flow path 162 extends horizontally, as shown in FIG. 3(b), and is further connected to a flow path 160 in the base 158. Therefore, the coolant that flows in from the flow path 160 flows horizontally in the flow path 162, as shown by the arrow E in FIG. 3(b).

In this way, in the grinding device 100, by circulating the coolant used to clean the workpiece 102 through the mounting jig 156 of the master workpiece 112, the temperature of the master workpiece 112 can be stabilized while the temperature of the workpiece 102 and the temperature of the master workpiece 112 can be made closer to each other. This allows the master workpiece 112 to be placed in an environment closer to that of the workpiece 102.

Figure 4 is a flow chart showing the operation of the grinding device 100 in Figure 1. Figure 5 is a diagram showing an example of the grinding device 100 performing each operation in Figure 4. In the grinding device 100, first, the track surface of the workpiece 102 is ground by the grinding machine 108 (see Figure 1 (b)) (step S100). During grinding of the workpiece 102, the measuring machine 110 is moved and placed on standby above the cleaning chamber 124.

Next, apart from supplying coolant during grinding, the workpiece 102 after grinding is washed with coolant by the coolant washing nozzles 152, 154, and further cleaned by air blowing by the air blow nozzles 148, 150 (step S102). Next, the shutters 142 provided on the top surface 140 of the washing chamber 124 and the measuring chamber 120 are opened (step S104).

Then, as shown by the arrow F in FIG. 5(a), the measuring device 110 is lowered and enters the cleaning chamber 124 through the top surface 140 with the shutter 142 (dotted line in the figure) open, and the measuring probes 136, 138 are cleaned by the air blow nozzles 144, 146, 151 and the coolant cleaning nozzle 155 (step S106).

Next, as shown by arrow G in FIG. 5(b), the measuring device 110 is raised and withdrawn from the cleaning chamber 124, and then moved horizontally to wait above the measuring chamber 120. The measuring device 110 is then lowered as shown by arrow G, and enters the measuring chamber 120 from the top surface 140 with the shutter 142 open, and the master work 112 is cleaned by blowing air with the air blow nozzles 144, 146 (step S108).

Next, the measuring machine 110 presses the probes 136, 138 against the master work 112 using the arms 132, 134 (see FIG. 2(b)) to measure the dimensions of the master work 112, thereby calibrating the measuring machine 110 itself (step S110).

Next, as shown by the arrow H in FIG. 5(c), the measuring machine 110 is raised and withdrawn from the measuring chamber 120, and then the shutter 142 is closed (step S112), and the measuring machine 110 is moved horizontally to wait above the grinding chamber 122. Then, as shown by the arrow H, the measuring machine 110 is lowered and enters the grinding chamber 122, where the workpiece 102 is cleaned by air blowing, for example, with the air blow nozzles 144, 146, 148, and 150 (step S114).

Furthermore, as shown in FIG. 5(c), the measuring machine 110 presses the measuring probes 136, 138 against the workpiece 102 using the arms 132, 134 (see FIG. 2(b)) to measure the dimensions of the workpiece 102 at two or more locations (step S116).

Next, similar to step S106, the measuring probes 136, 138 are cleaned in the cleaning chamber 124 by the air blow nozzles 144, 146, 151 and the coolant cleaning nozzle 155 (step S118). Similarly to step S108, the master workpiece 112 in the measuring chamber 120 is cleaned by the air blow nozzles 144, 146 (step S120). Then, similar to step S110, the dimensions of the master workpiece 112 are measured again (step S122).

The grinding device 100 then compares the dimensions of the master workpiece 112 measured in step S110 with the dimensions of the master workpiece 112 measured in step S122, and if the error between the two is not within the allowable range (step S124, No), it displays an error and prompts the operator to check for an abnormality (step S126). If the error is within the allowable range (Yes), it performs the operation of step S128.

If the dimensions of the workpiece 102 measured in step S116 are not within the tolerance range (No) in step S128, the grinding device 100 returns to step S100 and performs correction processing to correct the error. On the other hand, if the dimensions of the workpiece 102 are within the tolerance range (Yes) in step S128, the operation ends.

In this way, in the grinding device 100, before the measuring machine 110 measures the dimensions of the workpiece 102, the measuring machine 110 is calibrated by measuring the master workpiece 112, which is in an environment similar to that of the workpiece 102. Therefore, according to the grinding device 100, the measuring machine 110 measures the dimensions of the workpiece 102 after calibration, i.e., in a state where the reliability of the measurement is increased, so that the dimensions of the workpiece 102 can be measured with high accuracy, and furthermore, by performing correction processing so that the workpiece 102 has the specified dimensions, grinding processing with high dimensional accuracy can be performed.

In addition, the mounting jig 156 (see Figure 3) on which the master work 112 is attached circulates coolant to clean the work 102, so the master work 112 can be placed in an environment closer to that of the work 102, further improving the reliability of measurements by the measuring device 110 after calibration.

In addition, in the grinding device 100, after the workpiece 102 is ground by the grinding machine 108 and before the dimensions of the workpiece 102 are measured by the measuring machine 110, the workpiece 102 is washed again with coolant.

In other words, in the grinding device 100, coolant is supplied during grinding, but separately, before the dimensions of the workpiece 102 after grinding are measured by the measuring device 110, the workpiece 102 is washed with coolant, so that grinding powder adhering to the workpiece 102 can be almost certainly removed, and the dimensions of the workpiece 102 can be accurately measured by the measuring device 110. In addition, because the workpiece 102 is washed again with coolant and further cooled, dimensional deviations due to thermal expansion accompanying temperature changes of the workpiece 102 during grinding can be reduced.

In addition, the grinding device 100 cleans the workpiece 102, master workpiece 112, and measuring probes 136, 138 with air blowing before measuring the workpiece 102 and master workpiece 112 with the measuring device 110. Therefore, according to the grinding device 100, grinding powder adhering to the workpiece 102, master workpiece 112, and measuring probes 136, 138 can be removed by air blowing, and the dimensions of the workpiece 102 can be accurately measured by the measuring device 110.

The grinding device 100 is divided into a cleaning chamber 124 for cleaning the measuring probes 136 and 138 and a measuring chamber 120 for installing the master workpiece 112 by partitions 126, 128, and 130, and a shutter 142 is provided on the partition, i.e., the top surface 140, through which the measuring device 110 enters and exits.

Therefore, in the grinding device 100, the grinding powder generated in the grinding chamber 122 during grinding of the workpiece 102 is blocked by the shutter 142 and does not enter the cleaning chamber 124 or the measurement chamber 120 from the grinding chamber 122. As a result, the grinding powder does not adhere to the measuring probes 136, 138 of the measuring machine 110 or the master workpiece 112, preventing measurement errors caused by the grinding powder.

In the above embodiment, the workpiece 102 and the master workpiece 112 have been described as rails with grooves 160, 162 on both side surfaces (both outer surfaces) of a rectangular workpiece. However, they may also be blocks with grooves on both inner surfaces of a U-shaped workpiece. The block and workpiece are provided with rolling elements in the opposing grooves (raceway surfaces), and the block moves along the workpiece. Even in such a case, the measuring machine is calibrated by measuring the master workpiece in an environment similar to that of the workpiece before measuring the dimensions of the workpiece, and the dimensions of the workpiece can be measured after calibration, i.e., after the measurement reliability has been increased.

Although the preferred embodiment of the present invention has been described above with reference to the attached drawings, it goes without saying that the present invention is not limited to such an example. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

The present invention can be used as a raceway grinding machine that grinds a workpiece to form the raceway surface of rolling elements on rails or blocks.

100...grinding device, 102...workpiece, 104...table, 106...column, 108...grinding machine, 110...measuring machine, 112...master workpiece, 114...base, 116, 118...grinding wheel, 120...measuring chamber, 122...grinding chamber, 124...cleaning chamber, 126, 128, 130...partition wall, 132, 134...arm, 136, 138...measuring probe, 140...top surface, 142...shutter, 144, 146, 148, 150, 151...air blow nozzle, 152, 154, 155...coolant cleaning nozzle, 156...mounting jig, 158...base, 160, 162...flow path

Claims (4)

a grinding unit that grinds a workpiece to form a raceway surface of a rolling element on the workpiece;
A measuring machine for measuring the dimensions of the workpiece;
a master workpiece that is placed near a processing position of the workpiece and is therefore in an environment similar to that of the workpiece ;
A mounting jig for mounting the master work ,
the measuring machine measures the dimensions of the workpiece after measuring the master workpiece and calibrating the measuring machine ;
A raceway surface grinding machine characterized in that a coolant for cleaning the workpiece is circulated through the mounting jig . The raceway surface grinding machine according to claim 1, characterized in that after the workpiece is ground by the grinding unit and before the dimensions of the workpiece are measured by the measuring machine, the workpiece is washed again with coolant. the measuring machine has a measuring probe pressed against the workpiece and the master workpiece,
3. The raceway surface grinding machine according to claim 1, wherein the workpiece, the master workpiece, and the measuring element are cleaned with an air blower before the workpiece and the master workpiece are measured by the measuring machine. The raceway surface grinding machine is divided into a machining chamber for machining the workpiece, a cleaning chamber for cleaning the measuring element, and a master measuring chamber in which the master workpiece is placed,
4. The raceway surface grinding machine according to claim 3 , wherein a shutter is provided on one of the partition walls of each of the compartments through which the measuring machine enters and exits.

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