GRINDER AND ITS SAFETY UNIT

Description

[0001] The present invention relates to a protective assembly according to claim 1 and a grinding machine according to claim 2, in particular to a grinding machine with an adjustable protective cover and its protective assembly.

[0002] In grinding machines, a workpiece is ground using a grinding wheel. To prevent sparks generated during grinding from being flung towards the user by the centrifugal force of the rotating grinding wheel, the grinding wheel is equipped with a protective cover.

[0003] To adjust the grinding angle of the grinding wheel, the guard is usually angle-adjustable. With current technology, the user must use a tool (e.g., a screwdriver) to unlock the guard before the angle can be further adjusted until the guard is in the correct position and locked into place. Therefore, there is a need to structurally improve existing guards.From WO 2020 / 012746 A1, an electrically driven tool is known, comprising a protective assembly for use in a machine body of a grinding machine, wherein the protective assembly includes: a protective cover rotatably arranged on one side of the machine body; a fastening assembly with a locking element; a switching element that can be moved relative to the machine body into a locking position or a release position, wherein in the locking position of the switching element the protective cover is clamped by the locking element and the machine body.

[0004] The object of the present invention is to offer a grinding machine and its protective assembly in which the position of a protective cover can be easily adjusted.

[0005] The problem is solved by a protective assembly with the combination of features of claim 1 and by a grinding machine with the features of claim 2.

[0006] An embodiment of the present invention discloses a grinding machine comprising a machine body, a protective cover, a mounting assembly, and a switching element. The mounting assembly comprises a locking element and a connecting element. The protective cover is located at least partially between the machine body and the locking element. The connecting element is attached to the locking element. The switching element comprises a pivot section and an actuating section. The pivot section is located on the side of the machine body facing away from the protective cover and is pivotably mounted on the connecting element. The pivot section has an outer circumferential surface with a first contact surface and a second contact surface. The first contact surface is a distance from the central axis of the pivot section. The second contact surface is a distance from the central axis of the pivot section.The first distance is greater than the second. The actuating section is connected to the pivoting section and serves to pivot the pivoting section relative to the connecting element. The switching element can be rotated relative to the machine body into a locking position or a release position. In the locking position of the switching element, the first contact surface is in contact with the machine body, so that the protective cover is clamped by the locking element and the machine body. In the release position of the switching element, the second contact surface is in contact with the machine body, releasing the protective cover from its clamped position by the locking element and the machine body, so that the protective cover can be rotated relative to the machine body.

[0007] Another embodiment of the present invention discloses a protective assembly for use in the machine body of a grinding machine. The protective assembly comprises a protective cover, a mounting assembly, and a switching element. The mounting assembly includes a locking element and a connecting element. The protective cover is located at least partially between the machine body and the locking element. The connecting element is attached to the locking element. The switching element comprises a pivot section and an actuating section. The pivot section is located on the side of the machine body facing away from the protective cover and is pivotably mounted on the connecting element. The pivot section has an outer circumferential surface comprising a first contact surface and a second contact surface. The first contact surface is spaced a certain distance from the central axis of the pivot section.The second contact surface has a second distance to the central axis of the pivot section. The first distance is greater than the second distance. The actuating section is connected to the pivot section and serves to pivot the pivot section relative to the connecting element. The switching element can be rotated relative to the machine body into a locking position or a release position. In the locking position of the switching element, the first contact surface is in contact with the machine body, so that the protective cover is clamped by the locking element and the machine body. In the release position of the switching element, the second contact surface is in contact with the machine body, releasing the protective cover from its clamped position by the locking element and the machine body, so that the protective cover can be rotated relative to the machine body.

[0008] In the grinding machine and its protective assembly according to the above embodiments, the switching element is pivotably arranged eccentrically on the mounting assembly, so that by directly actuating the switching element either the protective cover is clamped or locked, or the clamping can be released to adjust the position of the protective cover, without the need for an additional tool. This increases ease of operation.

[0009] The foregoing description and the following description of the embodiments serve to illustrate and explain the claims of the present invention.

[0010] Fig. 1 shows a three-dimensional partial view of a grinding machine according to an exemplary embodiment. Fig. 2 shows a partial exploded view of the grinding machine from Fig. 1 . Fig. 3 shows a partial section through the grinding machine made of Fig. 1with a switching element in a locking position. Fig. 4 shows a schematic partial view illustrating the operation of the grinding machine. Fig. 1 with the switching element in a release position. Fig. 5 shows a partial section through the grinding machine made of Fig. 1 with the switching element in the release position.

[0011] The following embodiments provide a more detailed explanation of the features and advantages of the exemplary embodiments of the present invention, enabling those skilled in the art to understand and implement these embodiments. It will be clear to those skilled in the art that the corresponding problems and advantages of the present invention can be readily derived from the disclosures contained in this description, the claims, and the drawings. The following exemplary embodiments serve to further illustrate the invention. The scope of protection of the invention is defined by the claims.

[0012] It will be on Figs. 1 to 3 Reference is made to the following: Fig. 1 a three-dimensional partial view of a grinding machine according to an embodiment of the present invention, Fig. 2 a partial exploded view of the grinding machine Fig. 1 and Fig. 3a partial cut through the grinding machine Fig. 1 showing a switching element in a locking position.

[0013] In one embodiment, the grinding machine 10 comprises a machine body 1, a protective cover 2, a mounting assembly 3 and a switching element 4.

[0014] The machine body 1 comprises a handle section 12, a hood section 11, and a drive element 13. The hood section 11 is attached to the handle section 12. The hood section 11 has a first surface 111, a second surface 112, and a receiving groove 113. The second surface 112 faces away from the first surface 111. The receiving groove 113 is located on the first surface 111 and has a groove base 1131, which is arranged on the side of the receiving groove 113 facing away from the second surface 112. The hood section 11 has two bores 114. The bores 114 are located in the receiving groove 113 and extend through the receiving groove 113 on the first surface 111 and the second surface 112. The drive element 13 is provided with a grinding wheel 5, which is pivotably mounted on the drive element 13.

[0015] The protective cover 2 is located on the side of the second surface 112 facing away from the first surface 111 and is rotatable relative to the machine body 1 about the axis of the drive element 13. The protective cover 2 comprises an upper cover section 21, a lower cover section 22, and a side cover section 23. The upper cover section 21 has an arc-shaped sliding groove 211. The lower cover section 22 is located on the side of the upper cover section 21 facing away from the hood. The side cover section 23 is connected to the upper cover section 21 and the lower cover section 22 on both sides. When grinding a workpiece with the grinding wheel 5, the protective cover 2 protects the user from grinding dust and sparks.

[0016] The fastening assembly 3 comprises a locking element 31, a connecting element 32, and two spring elements 33. The locking element 31 comprises a locking plate 311 and two hollow cylinders 312. The locking plate 311 is arranged on the side of the protective cover 2 facing away from the hood section 11, so that the protective cover 2 is located at least partially between the hood section 11 and the locking plate 311. The hollow cylinder 312 projects from the locking plate 311 and extends toward the hood section 11. The connecting element 32 comprises a first pin 321 and two second pins 322. The second pin 322 is located in the bore 114 and is inserted with both ends into the first pin 321 and the hollow cylinder 312. The spring element 33 is pushed onto the second pin 322. The spring element 33 rests with its opposite ends against the hood section 11 and the hollow cylinder 312.

[0017] The switching element 4 comprises a pivot section 41 and an actuating section 42. In the present embodiment, the pivot section 41 is located in the receiving groove 113 and is pivotably connected to the first pin 321. The pivot section 41 has an outer circumferential surface facing away from the central axis R1 of the first pin, which has a first contact surface 411 and a second contact surface 412. The first contact surface 411 has a first distance D1 from the central axis R1 of the first pin. The second contact surface 412 has a second distance D2 from the central axis R1 of the first pin. The first distance D1 is greater than the second distance D2. In other words, the pivot section 41 is pivotably arranged eccentrically on the first pin 321, so that the distance between the central axis R1 of the first pin and the groove bottom 1131 changes with the pivoting of the pivot section 41.The actuating section 42 is connected to the pivoting section 41 and serves to pivot the pivoting section 41 relative to the first pin 321.

[0018] In the present embodiment, the actuating section 42 comprises a first section 421, two second sections 422, and two third sections 423. The first section 421 is connected to the pivot section 41 and extends from the hood section 11 to the handle section 12. The two second sections 422 are connected to two opposite sides of the first section 421 and extend towards the protective cover 2. The two third sections 423 are each connected to the side of the two second sections 422 facing away from the first section 421. A first reference plane E1 is defined, the normal of which runs parallel to the central axis R2 of the second pin and is tangential to the side of the handle section 12 facing away from the protective cover 2.A second reference plane E2 is defined, the normal of which runs parallel to the central axis R2 of the second pin and is tangential to the side of the handle section 12 facing the protective cover 2. The third section 423 is located between the first reference plane El and the second reference plane E2 and extends away from the central axis in the direction of the outer circumferential surface of the handle section 12. The two arrangements, each consisting of a second section 422 and a third section 423, are arranged symmetrically with respect to the first section 421.

[0019] The third section 423 extends away from the central axis towards the outer circumferential surface of the handle section 12, which allows the user to easily operate the switching element 4.

[0020] It will be directed to the Figures 4 to 5 referred to Fig. 4 a schematic partial view to illustrate the functioning of the grinding machine Fig. 1with the switching element in a release position and Fig. 5 a partial cut through the grinding machine Fig. 1 with the switching element in the release position.

[0021] In the present embodiment, the switching element 4 can be rotated relative to the machine body 1 in the F1 direction into a locking position or relative to the machine body 1 in the F3 direction into a release position. When the switching element 4 is in the locking position, the first contact surface 411 is in contact with the hood section 11, so that the central axis R1 of the first pin is aligned with the first distance D1 to the groove bottom 1131. The connecting element 32 then moves the locking plate 311 in the F2 direction close to the machine body 1 so that the locking plate 311 and the machine body 1 can clamp the protective cover 2. This compresses the spring element 33. In the release position of the switching element 4, the second contact surface 412 is in contact with the machine body 1, so that the central axis R1 of the first pin is aligned with the second distance D2 to the groove bottom 1131.The connecting element 32 then moves the locking plate 311 away from the machine body 1 in the F5 direction and releases the protective cover 2 from its clamped position between the locking plate 311 and the machine body 1, so that the protective cover 2 can be rotated relative to the machine body 1 in the F4 direction or in a direction opposite to F4. This releases the spring element 33 from its compressed state. In other words, since the switching element 4 is pivotably mounted eccentrically on the connecting element 32, the distance between the central axis R1 of the first pin and the receiving groove 113 changes when the switching element 4 moves between the locking and release positions. This change in the distance between the central axis R1 of the first pin and the groove bottom 1131 moves the connecting element 32 up and down, which in turn drives the locking plate 311 and the machine body 1 to clamp the protective cover 2 or release the clamping force.

[0022] The protective cover 2 can be adjusted without the use of any additional tools by switching it between a locked and a movable position using the switching element 4. The position of the protective cover 2 can be adjusted to the grinding angle of the grinding wheel 5, allowing the user to work at different grinding angles while remaining protected by the protective cover 2.

[0023] Because the third section 423 is located between the first reference plane E1 and the second reference plane E2, it is possible to prevent the actuating section 42 from being pushed out of its locking position by an external object during operation.

[0024] In the present embodiment, the hood section 11 has a receiving groove 113. In other embodiments, the hood section can also be a flat surface without a receiving groove. In further embodiments, the pivoting section can also be arranged on a surface without a groove. It is sufficient if it is located on the side of the machine body facing away from the protective cover and is connected to the machine body. In still further embodiments, the handle section and the hood section can also be formed integrally or otherwise connected to each other, e.g., by gluing or locking, but are not limited to these methods.

[0025] In the present embodiment, the arc-shaped sliding groove 211 is located in the lower cover section 22. In other embodiments, the arc-shaped sliding groove may be located not in the lower cover section, but in the side cover section or in the upper cover section. In further embodiments, a sliding rail, for example, may be provided instead of a sliding groove structure, which, however, should not be considered a limitation.

[0026] In the present embodiment, the bore 114 is located in the receiving groove 113. In other embodiments, the bore may not be located in the receiving groove, but e.g. on the first surface, which should not be considered a limitation.

[0027] In the present embodiment, the locking element 31 comprises a locking plate 311, two hollow cylinders 312, and two spring elements 33. In other embodiments, the locking element may not include a hollow cylinder. In further embodiments, the locking element may not include a spring element.

[0028] In the present embodiment, the locking plate 311 and the hollow cylinders 312 are formed integrally. In other embodiments, the locking plate and the hollow cylinders can be connected to each other in other ways, e.g. by gluing, snapping, but are not limited to these methods.

[0029] In the present embodiment, the spring element 33 rests against the hollow cylinder 312. In other embodiments, the spring element and the hollow cylinder can be connected to each other in other ways, e.g. by gluing, but are not limited to this.

[0030] In the present embodiment, the second pin 322 is inserted into the first pin 321. In other embodiments, the first pin and the second pin can be connected to each other in other ways, e.g., as a single piece, glued together, but not limited to this.

[0031] In the present embodiment, the third section 423 extends away from the central axis in the direction of the outer circumferential surface of the handle section 12. In other embodiments, the third section may also extend in other directions, e.g., in the direction of the housing, which, however, should not be considered a limitation.

[0032] In the present embodiment, the number of bores 114, hollow cylinders 312, second pins 322, spring elements 33, second sections 422, and third sections 423 is two, but is not limited to this. In other embodiments, the number of bores, hollow cylinders, second pins, spring elements, second sections, and third sections can be changed to one or more than three.

[0033] In the grinding machine according to the above embodiments and the protective assembly used therein, the switching element is pivotably arranged eccentrically on the mounting assembly, so that by directly actuating the switching element either the protective cover is clamped or the clamping force is released to adjust the position of the protective cover, without the need for an additional tool. This increases ease of use and allows for simple adjustment of the protective cover's position.

[0034] Exemplary embodiments have been disclosed so far, but these do not constitute a limitation of the present invention. Those skilled in the art will be aware that some modifications and adaptations are possible. Therefore, the scope of protection of the present invention is defined by the claims in the annex to this description. Reference symbol list

[0035] 10 Grinding machine 1 Machine body 11 Hood section 111 First surface 112 Second surface 113 Mounting groove 1131 Groove bottom 114 Bore 12 Handle section 13 Drive element 2 Protective cover 21 Upper cover section 211 Arc-shaped sliding groove 22 Lower cover section 23 Side cover section 3 Fastening assembly 31 Detent element 311 Detent plate 312 Hollow cylinder 32 Connecting element 321 First pin 322 Second pin 33 Spring element 4 Switching element 41 Swivel section 411 First contact surface 412 Second contact surface 42 Actuating section 421 First section 422 Second section 423 Third section 5 Grinding wheel D1 First distance D2 Second distance E1 First reference plane E2 Second reference plane R1 Center axis of the first pin R2 Center axis of the second pin F1 Direction F2 Direction F3 Direction F4 Direction F5 Direction

Claims

1. A protective assembly for use in a machine body (1) of a grinding machine (10), comprising: - a protective cover (2) able to be rotatably disposed on one side of the machine body (1); - a mounting assembly (3) having - a latching element (31), the protective cover (2) being present at least partially between the machine body (1) and the latching element (31); and - a connecting element (32) attached to the latching element (31), the connecting element (32) comprising the following: - a first pin (321) pivotably connected to a pivot segment (41) and at least one second pin (322) having both ends inserted in the first pin (321) and the latching element (31) so that the pivot segment (41) is pivotably disposed on the first pin (321) in an eccentric manner; - a switching element (4) having - the pivot segment (41) present on the side of the machine body (1) facing away from the protective cover (2) and pivotably supported on the connecting element (32), the pivot segment (41) comprising an outer circumferential surface facing away from the center axis (R1) of the first pin (321) and having a first contact surface (411) and a second contact surface (412), the first contact surface (411) having a first spacing (D1) from the center axis of the pivot segment (41) and the second contact surface (412) having a second spacing (D2) from the center axis of the pivot segment (41), the first spacing (D1) being greater than the second spacing (D2); and - an actuating segment (42) connected to the pivot segment (41) and serving for pivoting the pivot segment (41) relative to the connecting element (32); the switching element (4) being able to be rotated relative to the machine body (1) into a locked position or a released position, the first contact surface (411) being in contact with the machine body (1) in the locked position of the switching element (4) so that the protective cover (2) is clamped by the latching element (31) and the machine body (1), and the second contact surface (412) being in contact with the machine body (1) in the released position of the switching element (4), the protective cover (2) being released from the state of being clamped by the latching element (31) and the machine body (1) so that the protective cover (2) can be rotated relative to the machine body (1), the protective cover (2) comprising the following: - a top cover segment (21) - a bottom cover segment (22) present on the side of the top cover segment (21) facing away from the machine body (1); and - a side cover segment (23) connected to the top cover segment (21) and the bottom cover segment (22) on both sides, wherein the top, bottom, or side cover segment (21, 22, 23) comprises a curved sliding groove in which the connecting element (32) is partially present or a sliding track.

2. A grinding machine (10) comprising: - a machine body (1) and a protective assembly, characterized in that the protective assembly is implemented according to claim 1.

3. The grinding machine (10) according to claim 2, wherein the machine body (1) comprises a handle segment and a cowling segment, wherein the cowling segment is attached at an end surface of the handle segment and comprises a first surface, a second surface facing away from the first surface and spaced further apart from the protective cover (2) in comparison with the first surface, and a receiving groove present on the second surface, the pivoting segment (41) being disposed therein.

4. The grinding machine (10) according to claim 3, wherein the cowling segment further comprises at least one hole present in the receiving groove and extending through the first surface and the second surface, wherein the connecting element (32) is partially present in the at least one hole and is attached to the mounting element.

5. The grinding machine (10) according to claim 4, wherein the at least one second pin is present in the at least one hole.

6. The grinding machine (10) according to claim 5, wherein the actuating segment (42) comprises the following: - a first segment connected to the pivoting segment (41); - a second segment connected to the first segment and extending along the handle segment in the direction of the protective cover (2); and - a third segment connected to the side of the second segment facing away from the first segment, wherein a first reference plane is defined, the normal thereof running parallel to the center axis of the second pin (322) and running tangential to the side of the handle segment facing away from the protective cover (2), and wherein a second reference plane is defined, the normal thereof running parallel to the center axis of the second pin (322) and running tangential to the side of the handle segment facing toward the protective cover (2), wherein the third segment is present between the first reference plane and the second reference plane.

7. The grinding machine (10) according to claim 5, wherein the latching element (31) comprises the following: - a latching plate present on the side of the protective cover (2) facing away from the machine body (1); - at least one hollow cylinder protruding from the latching plate and extending in the direction of the machine body (1); and - at least one spring element placed over the at least one second pin (322), the opposite ends thereof contacting the cowling segment and the at least one hollow cylinder.