Belt changer

Abstract

To enable automatic belt replacement of belt grinders, eliminating the need for manual labor. [Solution] A belt changer 10 is configured to automatically replace the belt 21 of a belt grinder 20. The belt changer 10 consists of a base plate 11, a belt clamp 12, and a belt bender 13. The base plate 11 is capable of positioning the belt 21. The belt clamp 12 is movable in a direction toward and toward the long side of the belt 21, which is positioned in an elliptical loop shape on the base plate 11, and holds the belt 21 so that it does not shift in the width direction when it approaches. The belt bender 13 is movable in a direction toward and toward the short side of the belt 21, which is positioned in an elliptical loop shape on the base plate 11, and presses against the short side of the belt 21 to flex it when it approaches, and releases the belt 21 from flexing when it moves away. By appropriately operating the belt clamp 12 and the belt bender 13, the attachment and detachment of the belt 21 to the belt grinder 10 is automated.

Description

[Technical Field]

[0001] The present invention relates to a belt changer for replacing (attaching and detaching) the belt of a belt grinder. [Background Art]

[0002] As disclosed in Patent Document 1, there is known a belt grinder that grinds and polishes a workpiece by pressing it against the workpiece while rotating an endless belt wound in an elliptical loop between a drive pulley and an idle pulley. The distance between the drive pulley and the idle pulley is expandable and contractable, whereby the tension of the belt is adjusted. Since this belt deteriorates due to progress of wear and the like with use, it needs to be replaced in a timely manner. Conventionally, attaching and detaching the belt to and from the belt grinder has been performed manually.

[0003] Manually replacing the belt of a belt grinder as described above is time-consuming and cumbersome. In particular, the present inventors have attempted to automate grinding and polishing work by attaching a belt grinder to an articulated robot (robot arm). However, if manual work is required for the belt replacement step, efficiency cannot be improved, and the purpose of automation is negated. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Laid-Open No. 09-225829 [Summary of the Invention] [Problem to be Solved by the Invention]

[0005] Therefore, the problem to be solved by the present invention is to enable automatic replacement of the belt of a belt grinder without relying on manual work. [Means for Solving the Problem]

[0006] To solve the above-mentioned problems, the inventors have invented a belt changer capable of automatically replacing the belt of a belt grinder.

[0007] More specifically, the belt changer according to the invention comprises: a base plate capable of positioning an endless elliptical loop-shaped belt on its plate surface; a belt clamp that is movable in a direction approaching and moving away from the long side of the elliptical loop-shaped belt positioned on the base plate, and holds the belt in place to prevent it from shifting in the width direction when approaching and releases the belt from holding it in the width direction when moving away; and a belt bender that is movable in a direction approaching and moving away from the short side of the elliptical loop-shaped belt positioned on the base plate, and presses the short side of the belt to flex it when approaching and releases the belt from flexing when moving away.

[0008] With this configuration, when removing the belt from the belt grinder, first, the belt grinder with the belt attached is positioned against the base plate, and with the belt positioned on the plate surface, the belt clamp is brought close to hold it in place so that it does not slip. Then, with the tension on the belt released, the belt bender is brought close and bent. This creates a gap between the belt grinder and the belt held on the base plate, and when only the belt grinder is moved away from the base plate, the belt is removed. Furthermore, when attaching the belt to the belt grinder, the belt grinder without the belt attached is positioned opposite the base plate that holds the belt clamp. With the belt positioned around the belt grinder, tension is applied to the belt by increasing the distance between the drive pulley and the idler pulley and moving the belt bender away from the belt. The fixing is then released by moving the belt clamp away from the belt. In this state, the belt grinder and belt are moved away from the base plate, and the belt is attached. In this way, the belt changer can automatically attach and detach the belt from the belt grinder.

[0009] The belt changer according to the invention may have a configuration that includes a plurality of guide pins erected on a base plate, which can be guided to conform to both long sides and one short side of the belt so that the belt is positioned in an elliptical loop shape. This configuration allows for a simple structure in which the belt can be positioned in an elliptical loop shape on a base plate.

[0010] The belt changer according to the invention can be configured to have a plurality of push pins erected on a belt bender, which press against the short side of the belt and cause it to bend when the belt approaches. This configuration allows for a simple structure that can flex a belt positioned on a base plate.

[0011] In the belt changer according to the invention, the belt clamp has a pair of opposing holders, each of which can move toward and away from the long sides of the belt, and the holders can be configured to hold the long sides of the belt in the width direction with their bifurcated ends so that they do not slide. This configuration allows for a simple structure that prevents the belt on the base plate from shifting laterally in the width direction.

[0012] In the belt changer according to the invention, the belt clamp and belt bender can be configured to move closer to and further away from the belt positioned on the base plate by the extension and retraction of an air cylinder. This configuration allows for a simple structure to move the belt clamp and belt bender closer to and further away from the belt.

[0013] To solve the above-mentioned problems, the belt changer set according to the invention consists of a set of belt changers according to the invention, one of which is dedicated to removing the old belt from the belt grinder, and the other belt changer is dedicated to installing a new belt onto the belt grinder. With this configuration, the process of removing the belt with one belt changer and installing the belt with the other belt changer can be performed continuously and efficiently, thus streamlining the process of replacing old and new belts.

[0014] To solve the above-mentioned problems, the present invention provides a method for removing a belt from a belt grinder, which is capable of adjusting the belt tension by expanding or contracting the distance between the drive pulley and the idler pulley, using a belt changer according to the invention. This method includes the steps of: positioning the belt grinder with the belt attached opposite each other on a base plate; bringing the belt clamp close to the belt and holding its long side from the width direction; loosening the belt by reducing the distance between the drive pulley and the idler pulley of the belt grinder; bringing the belt bender close to the belt and pressing its short side to bend it, thereby creating a gap between the belt grinder and the belt; and moving the belt grinder away from the base plate, leaving the belt in place, and removing the belt. This configuration allows for efficient and automated removal of the belt from the belt grinder.

[0015] In order to further solve the problem described above, the present invention provides a belt attaching method according to the invention, in which a belt changer according to the invention is used to attach a belt to a belt grinder capable of adjusting belt tension by expanding or contracting the distance between a drive pulley and an idle pulley. The method comprises: positioning the belt on a base plate; causing an unloaded belt grinder with no belt mounted thereon to face the base plate; tensioning the belt on the belt grinder by expanding the distance between the drive pulley and the idle pulley of the belt grinder; moving belt benders away from the belt to release the short sides of the belt from pressing; moving belt clamps away from the belt to release the long sides of the belt from being held in the width direction; and retracting the belt grinder together with the belt from above the base plate. With this configuration, the work of attaching a belt to a belt grinder can be performed efficiently and automatically. Effects of the Invention

[0016] Since the belt changer and the like according to the invention are configured as described above, it becomes possible to automatically replace the belt of a belt grinder without relying on manual work. Brief Description of the Drawings

[0017] [Figure 1] Perspective view of a belt grinder and a belt changer [Figure 2] Front view of the belt changer [Figure 3] Perspective view of essential parts of the belt grinder [Figure 4] Front view showing a belt removing step [Figure 5] Front view showing a belt removing step [Figure 6] Front view showing a belt removing step [Figure 7] Front view showing a belt attaching step [Figure 8] Front view showing a belt attaching step [Figure 9]Front view showing the belt installation process. [Modes for carrying out the invention]

[0018] Embodiments of the present invention will be described below with reference to the drawings. As shown in Figures 1 and 2, the belt changer 10 of the embodiment is used as a set of belt changers, and as shown in the figures, it can automatically replace the belt 21 of the belt grinder 20, which is attached to the articulated robot R shown in Figures 2 and 3 and can automatically perform grinding and polishing work, without manual operation.

[0019] As shown in Figures 2 and 3, the belt grinder 20 has parallel drive pulleys 22 and idler pulleys 23, and an endless belt 21 is wound in an elliptical loop from the drive pulleys 22 to the idler pulleys 23. A tensioner 24 is provided between the drive pulley 22 and the idler pulley 23. By changing the distance between the drive pulley 22 and the idler pulley 23 using appropriate means such as a cylinder extension / retraction mechanism or a tilt mechanism, the tension of the belt 21 can be adjusted. When the distance between the drive pulley 22 and the idler pulley 23 is narrowed, the belt 21 is loosened, and when the distance between the drive pulley 22 and the idler pulley 23 is widened, the belt 21 is tightened (tension is applied).

[0020] The drive pulley 22 is rotationally driven by the motor 25, which in turn rotates the belt 21. When the belt is pressed against the object in this state, grinding and polishing of the object is performed. The idler pulley 23 is capable of free rotation. A cover 26 is provided to cover a portion of the belt 21, preventing debris, dust, and other particles from scattering during grinding and polishing.

[0021] As shown in Figures 1 and 2, a set of belt changers 10 forming a belt changer set are fixed on a work table T in two tiers, upper and lower. Each belt changer 10 includes a base plate 11, a belt clamp 12, and a belt bender 13.

[0022] As shown in Figures 1 and 2, the base plate 11 is fixed so that its surface is perpendicular to the work table T, and a plurality of guide pins 11a are erected on its surface. The guide pins 11a are arranged in parallel in a horizontal U-shape, allowing the belt 21 to be positioned in an elliptical loop on the surface of the base plate 11. With the belt 21 in position, the guide pin 11a follows both long sides (top and bottom in the figure) and one short side (right side in the figure) of the belt 21. Furthermore, a window 11b is provided in the area surrounded by the guide pins 11a of the base plate 11. This window 11b prevents dust and other particles from accumulating on the surface of the base plate 11.

[0023] As shown in Figures 1 and 2, the belt clamps 12 are provided in pairs facing each other in the vertical direction on the base plate 11 and are attached to the base plate 11 by appropriate means. Each belt clamp 12 consists of a holder 12a and an air cylinder 12b. The holder 12a is bent in a U-shape, and its tips, located at both ends of the U-shape, can hold the long side of the belt 21 positioned on the base plate 11 at two points. As shown in Figure 1, the tip of the holder 12a is split into two in the width direction of the belt 21, and by holding the belt 21 between them, its movement in the width direction (lateral displacement) is prevented.

[0024] Furthermore, the holder 12a can slide vertically along the surface of the base plate 11, moving forward and backward, due to the extension and retraction of the air cylinder 12b. This allows the holder 12a of each belt clamp 12 to move closer to and further away from the long side of the belt 21 positioned on the base plate 11. When the holder 12a approaches, the belt 21 on the base plate 11 fits between the bifurcated ends of the holder 12a, holding it in place and preventing it from shifting in the width direction. On the other hand, when the holder 12a moves away, the belt 21 on the base plate 11 slips out from between the ends of the holder 12a, releasing it from being held in the width direction.

[0025] As shown in Figures 1 and 2, the belt bender 13 is located to the left of the base plate 11 and is attached to the base plate 11 by appropriate means. The belt bender 13 consists of a bender plate 13a, a push pin 13b, and an air cylinder 13c. The bender plate 13a is positioned so as to be almost flush with the base plate 11, and the push pins 13b are erected on its surface. The push pins 13b are arranged in a C-shape, and together with the guide pins 11a, which are arranged in a horizontal U-shape, they conform to almost the entire circumference of both long and short sides of the belt 21 positioned on the base plate 11. The push pins 13b alone conform to the other short side (left side in the figure) of the belt 21.

[0026] The bender plate 13a, on which the push pins 13b are erected, can slide forward and backward in the left-right direction parallel to the surface of the base plate 11 by the extension and retraction of the air cylinder 13c. This allows the push pins 13b to move closer to and further away from the other (left side in the figure) short side of the belt 21 positioned on the base plate 11. When the push pin 13b approaches, the belt 21 on the base plate 11 flexes as its short side is pressed against the push pin 13b. Conversely, when the push pin 13b moves away, the belt 21 on the base plate 11 is released from the pressure of the push pin 13b and the flexing stops.

[0027] The configuration of the belt changer 10 in this embodiment is as described above. Next, a method for replacing the belt 21 in this embodiment using a belt changer set consisting of a set of belt changers 10 will be described. Figures 4 to 6 show the process of removing the belt 21 from the belt grinder 20, and Figures 7 to 9 show the process of attaching the belt 21 to the belt grinder 20.

[0028] The process for removing the belt 21 begins by preparing a belt changer 10 in a standby state, as shown in Figure 4(a), with the belt 21 not positioned on the base plate 11 (in an empty state). For this belt changer 10, one of the two upper and lower belt changers 10 that make up the belt changer set (for example, the upper one) is used. Here, the holders 12a of the upper and lower belt clamps 12 are in a retracted position due to the contraction of the air cylinder 12b, and the bender plate 13a of the left belt bender 13 and the push pin 13b erected thereon are in a retracted position due to the extension of the air cylinder 13c.

[0029] In this state, the belt grinder 20, equipped with the used belt 21 to be replaced, is brought close to the belt changer 10 using the articulated robot R, as shown in Figure 4(b), and positioned against the plate surface of the base plate 11. At this point, the tensioner 24 of the belt grinder 20 is extended, and the belt 21 is stretched (tension is applied) between the drive pulley 22 and the idler pulley 23. With the belt grinder 20 facing the user, the endless elliptical loop-shaped belt 21 on the belt grinder 20 is positioned on the base plate 11 by the guide pin 11a, while maintaining its shape. Here, the other short side of the belt 21 (the left side in the figure) is sandwiched between the push pin 13b of the belt bender 13 and the drive pulley 22 of the belt grinder 20.

[0030] Next, as shown in Figure 5(a), the air cylinders 12b of the pair of belt clamps 12 are extended to advance the holder 12a. As the holder 12a moves forward, it approaches the belt 21 positioned on the base plate 11, and its bifurcated ends hold the long side of the belt 21 to prevent lateral displacement. Furthermore, as shown in Figure 5(b), the distance between the drive pulley 22 and the idler pulley 23 is narrowed by contracting the cylinder of the tensioner 24 of the belt grinder 20, thereby loosening the belt 21 stretched between them.

[0031] Then, as shown in Figure 6(a), the air cylinder 13c of the belt bender 13 is retracted, advancing the bender plate 13a and the push pin 13b erected thereon, bringing the push pin 13b closer to one of the short sides of the belt 21. As the push pin 13b presses against the short side of the belt 21, the entire loose belt 21 flexes, creating a gap between it and the drive pulley 22 and idler pulley 23 of the belt grinder 20. In this state, as shown in Figure 6(b), if the multi-joint robot R is used to move the belt grinder 20 away from the base plate 11, only the belt 21 will remain positioned on the base plate 11, and the belt 21 will be automatically removed from the belt grinder 20.

[0032] The process for installing the belt 21 begins by preparing a belt changer 10 in a standby state, as shown in Figure 7(a), with an unused belt 21 positioned on the base plate 11. This belt changer 10 is the other (for example, the lower) of the two upper and lower belt changers 10 that make up the belt changer set. Here, the holders 12a of the pair of belt clamps 12 are in a forward position due to the extension of the air cylinder 12b, and are close to both long sides of the belt 21 positioned on the base plate 11. The bifurcated tips of the holders 12a hold the belt 21 so that it does not shift in the width direction. Furthermore, the bender plate 13a of the belt bender 13 and the push pin 13b erected thereon are in an advanced position due to the contraction of the air cylinder 13c, and are approaching one of the short sides (the left side in the figure) of the belt 21 positioned on the base plate 11. In this state, the push pin 13b is pressing against the short side of the belt 21, and as a result, the belt 21 positioned on the base plate 11 is flexed as a whole.

[0033] As shown in Figure 7(b), a belt grinder 20 from which the used belt 21 from the previous process has been removed is brought close to the belt changer 10, which is fitted with an unused belt 21, using an articulated robot R, and brought into contact with the surface of the base plate 11. At this point, the tensioner 24 of the belt grinder 20 is retracted, and the distance between the drive pulley 22 and the idler pulley 23 is narrowed.

[0034] From here, as shown in Figure 8(a), the distance between the drive pulley 22 and the idler pulley 23 is increased by extending the cylinder of the tensioner 24 of the belt grinder 20. As a result, one short side of the belt 21 (the left side in the figure) is sandwiched between the drive pulley 22 of the belt grinder 20 and the push pin 13b of the belt bender 13. Furthermore, as shown in Figure 8(b), the extension of the air cylinder 13c of the belt bender 13 causes the push pin 13b to retract together with the bender plate 13a, thereby separating the push pin 13b from one of the shorter sides (the left side in the figure) of the belt 21. As a result, the belt 21 is released from the pressure of the push pin 13b, tension is applied to the belt 21 by the tensioner 24, and the belt is stretched between the drive pulley 22 and the idler pulley 23.

[0035] Next, as shown in Figure 9(a), the air cylinders 12b of the pair of belt clamps 12 are retracted to retract the holder 12a. As the holder 12a retracts, it separates from the belt 21 on the base plate 11, and both long sides of the belt 21 are released from its hold. In this state, as shown in Figure 9(b), when the multi-joint robot R is used to retract the belt grinder 20 from the base plate 11, the belt 21, which is stretched on the belt grinder 20 and released from being held by the holder 12a and pressed by the push pin 13b, is retracted together with it, and the belt 21 is automatically attached to the belt grinder 20.

[0036] As described above, by using the belt changer 10, the belt 21 of the belt grinder 20 can be replaced automatically without manual labor. By automating the grinding and polishing operations of the belt grinder 20 with the articulated robot R, all operations from grinding and polishing to belt replacement can be automated.

[0037] The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims and includes all modifications and changes within that scope and in the sense of equivalent thereto.

[0038] In this embodiment, a set of belt changers 10 forming a belt changer set are arranged in two tiers, one above the other. However, the arrangement is not limited to this; they can also be arranged in two columns, left and right, or in different positions on the work table. Furthermore, the belt changer set may consist of three or more belt changers 10. In addition, a single belt changer 10 can perform both the removal and installation of the belt 21. In that case, the used belt 21 removed from the belt grinder 20 is removed from the belt changer, an unused belt 21 is attached to the belt changer 10, and then the belt is attached to the belt grinder 20.

[0039] In this embodiment, the belt changer 10 is positioned so that the surface of the base plate 11 is perpendicular to the surface of the work table T (vertically), but the orientation is not limited to this. The surface of the base plate 11 can also be positioned parallel to the surface of the work table T, or inclined relative to the work table T. The configuration of the belt clamp 12 and belt bender 13 of the belt changer 10 is not limited to any particular embodiment, as long as they can hold and flex the belt 21. For example, the belt clamp 12 can be a mechanism capable of suctioning the belt 21, or the belt bender 13 can be a mechanism such as a push rod that pushes the belt 21. The mechanism for moving the belt clamp 12 and belt bender 13 closer to and further away from the base plate 11 is not limited to air cylinders 12b and 13c, but can also be a hydraulic cylinder or a mechanism that can slide on a rail. The configuration of the base plate 11 is not limited as long as it can position the belt 21 in an elliptical loop shape. For example, instead of the guide pin 11a, a mechanism such as a frame can be used to position the belt 21.

[0040] The configuration of the belt grinder 20 is not limited to this embodiment, as long as the distance between the drive pulley 22 and the idler pulley 23 can be extended or retracted. For example, even for a belt grinder 20 that is not attached to an articulated robot R, the belt 21 can be automatically replaced by using the belt changer 10 of this embodiment. [Explanation of Symbols]

[0041] 10 Belt Changer 11 Base Plate 11a Guide pin 11b Window 12 Belt Clamps 12a Holder 12b Air Cylinder 13 Belt Bender 13a Bender Plate 13b Push pin 13c Air Cylinder 20 Belt grinder 21 belt 22 Drive Pulley 23 Idler Pulley 24 Tensioner 25 Motor 26 Cover R Articulated Robot T Work Table

Claims

1. A belt changer that allows belts to be attached to and detached from a belt grinder, A base plate capable of positioning the elliptical loop-shaped endless belt on its plate surface, A belt clamp is movable in a direction approaching and moving away from the long side of the belt, which is positioned in an elliptical loop shape on the base plate, and holds the belt so that it does not shift in the width direction when it approaches, and releases the belt from holding in the width direction when it moves away. A belt changer comprising: a belt bender that is movable in a direction toward and toward the short side of the belt positioned in an elliptical loop shape on the base plate, and presses against the short side of the belt to flex it when approaching, and releases the belt from flexing when moving away.

2. The belt changer according to claim 1, further comprising a plurality of guide pins erected on the base plate and capable of conforming to both long sides and one short side of the belt so that the belt is positioned in an elliptical loop shape.

3. The belt changer according to claim 1 or 2, further comprising a plurality of push pins erected on the belt bender, which press against and flex the belt along its short side when approached.

4. The belt clamp has a pair of opposing holders, each of which is movable toward and toward both long sides of the belt, and the holders hold the long sides of the belt with their bifurcated ends so as not to shift in the width direction, according to claim 1 or 2.

5. The belt changer according to claim 1 or 2, wherein the belt clamp and the belt bender are capable of moving closer to and further away from the belt positioned on the base plate by the extension and retraction of an air cylinder.

6. It consists of a set of belt changers according to claim 1 or 2, On the other hand, the belt changer is solely for removing the old belt from the belt grinder. The other belt changer is a belt changer set specifically for attaching a new belt to the belt grinder.

7. A method for removing a belt from a belt grinder capable of adjusting the belt tension by expanding or contracting the distance between the drive pulley and the idler pulley, using a belt changer according to claim 1 or 2, The process of positioning the belt grinder, on which the belt is attached, opposite the base plate, and positioning the belt thereon, The process involves bringing the belt clamp close to the belt and holding its long side from the width direction, The process of loosening the belt by reducing the distance between the drive pulley and the idler pulley of the belt grinder, The process involves bringing the belt bender close to the belt and pressing its short side to bend it, thereby forming a gap between the belt grinder and the belt. A method for removing a belt, comprising the steps of moving the belt grinder away from the base plate, leaving the belt in place, and removing the belt.

8. A method for attaching a belt to a belt grinder capable of adjusting the belt tension by expanding or contracting the distance between the drive pulley and the idler pulley, using the belt changer described in claim 1 or 2, A step of positioning the belt on the base plate. The steps include: positioning the belt grinder, which does not have the belt attached, on the base plate; The process involves stretching the belt on the belt grinder by increasing the distance between the drive pulley and the idler pulley of the belt grinder, The process of separating the belt bender from the belt and releasing its short side from pressure, The process involves separating the belt clamp from the belt and releasing its long side from holding in the width direction, A method for attaching a belt, comprising the step of retracting the belt grinder, together with the belt, from the base plate.

Images