1. Field of the Invention
The present invention relates generally to a power grinder, and more particularly to an installation/uninstallation structure for tooling disk of a grinder or a sander.
2. Description of the Related Art
A conventional electric or pneumatic grinder includes a grinding wheel/grinding disk mounted on a rotary shaft for grinding a work piece. The grinding wheel is a consumable product and needs to be replaced frequently.
In the conventional grinder, the grinding wheel is fixed at a rear end of the rotary shaft by a nut. When installing/uninstalling the grinding wheel, it is necessary to use one hand tool for holding the rotary shaft and another hand tool for screwing/unscrewing the nut. Therefore, the replacement of the grinding wheel necessitates two hand tools and is quite inconvenient.
Many improved installation/uninstallation structures are disclosed by the inventor in, for example, U.S. Pat. No. 7,014,548, U.S. Pat. No. 7,179,156, U.S. Pat. No. 7,128,641, U.S. Pat. No. 6,887,141, etc. In the improved installation/uninstallation structure, an engaging means is disposed in the grinding tool for locking the rotary shaft and hindering the rotary shaft from rotating. In this case, the grinding wheel can be installed/uninstalled with only one hand tool.
In such improved installation/uninstallation structure, the rotary shaft can be locked with the engaging means so that an operator can more conveniently replace the grinding wheel. However, the operator still needs to use one hand tool for screwing/unscrewing the screw member. In this case, it still takes some time to complete the replacement of the grinding wheel.
Moreover, the engaging means is mounted in the body of the grinding tool and has a complicated structure. In addition, it is hard to assemble the engaging means so that the manufacturing cost is increased.
It is therefore a primary object of the present invention to provide an installation/uninstallation structure for tooling disk of a grinding tool. By means of the installation/uninstallation structure, a user can more easily replace the tooling disk without using any hand tool.
It is a further object of the present invention to provide the above installation/uninstallation structure for the tooling disk of the grinding tool. By means of the installation/uninstallation structure, a user can more quickly replace the tooling disk.
It is still a further object of the present invention to provide the above installation/uninstallation structure for the tooling disk of the grinding tool. The installation/uninstallation structure is applicable to the grinding tool as an external device without changing the internal structure of the grinding tool.
To achieve the above and other objects, the installation/uninstallation structure for the tooling disk of the grinding tool of the present invention includes a rotary shaft mounted in the grinding tool and a securing assembly mounted on the rotary shaft. An annular groove is formed on a circumference of the rear end of the rotary shaft. The securing assembly includes a securing seat, a shift plate and a securing member. The securing seat has a through hole and a slide way. The securing member is slidably mounted in the slide way of the securing seat. The shift plate is pivotally disposed on the securing seat and movable between a locking position and an unlocking position. When shifting the shift plate, the shift plate drives the securing member to move within the slide way.
The securing assembly is fitted on the rear end of the rotary shaft. When the shift plate is shifted to the locking position, the shift plate drives the securing member to move toward an inner end of the slide way and makes an inner end of the securing member move into the through hole of the securing seat to be latched in the annular groove of the rotary shaft. At this time, the securing assembly is secured to the rotary shaft for fixing the tooling disk. When the shift plate is shifted to the unlocking position, the shift plate drives the securing member to move toward an outer end of the slide way and makes the inner end of the securing member move out of the annular groove and the securing member is released from the rotary shaft. In this case, the securing assembly can be detached from the rotary shaft for taking off the tooling disk.
As a result, the tooling disk can be replaced more easily and quickly without using any hand tool.
The present invention can be best understood through the following description and accompanying drawings, wherein:
Please refer to
The present invention comprises a rotary shaft 10 mounted on a grinding tool and a securing assembly 20. For easy illustration, the rotary shaft 10 is shown in
The rear end of the rotary shaft 10 has a circumference on which an annular groove 12 is formed. The annular groove 12 has a beveled top wall 121 and a beveled bottom wall 122 as shown in
The securing assembly 20 includes a securing seat 30, a shift plate 40 and a securing member 50.
The securing seat 30 has a through hole 32 passing through the securing seat 30 from a top face to a bottom face thereof, and a slide way 34 radially formed on a rear side of the securing seat 30. An inner end of the slide way 34 communicates with the through hole 32. An outer end of the slide way 34 is formed as a slot 36 passing through the securing seat between two lateral sides thereof. A recess 38 is formed at a front end of the securing seat 30.
The securing member 50 is mounted in the slide way 34 as shown in
In this embodiment, the shift plate 40 includes a front piece 42 and a rear piece 44 pivotally connected with each other to form a linking mechanism. The front piece 42 has a top wall 421 and two lateral walls 422. Rear ends of the lateral walls 422 are pivotally connected to two lateral sides of the securing seat 30 via pivot shafts 45 as shown in
The shift plate 40 can be shifted to a locking position as shown in
Referring to
In addition, the top walls 421, 441 of the front and rear pieces 42, 44 are respectively formed with semicircular notches 423, 443. When the shift plate 40 is positioned in the locking position, the two notches 423, 443 together form a circular perforation in alignment with the through hole 32 of the securing seat 30. Accordingly, the through hole 32 will not be blocked by the shift plate.
In the present invention, a height adjustment mechanism 60 is further disposed in the rotary shaft 10. Referring to
The height adjustment mechanism 60 includes an adjustment rod 70, two engaging members 80 and a press member 90.
The adjustment rod 70 is a stepped cylindrical rod, having a top end as a head section 72. An outer circumference of the adjustment rod 70 is formed with an outer thread 74. A cavity 75 is formed on the top end of the adjustment rod 70. Two apertures 76 are radially formed through a tubular wall of the adjustment rod 70 in communication with the cavity 75. The adjustment rod 70 is mounted in the socket 14 of the rotary shaft 10 and screwed into the threaded hole 15 with the head section 72 protruding from the rear end of the rotary shaft 10. When rotating the adjustment rod, the length of a section of the adjustment rod that protrudes from the rotary shaft can be adjusted. The aforesaid annular groove 12 is formed on a circumference of the head section 72. A first resilient member 78, which is a spring, is mounted in the threaded hole 15. A top end of the resilient member 78 resiliently abuts against an inner end of the adjustment rod 70.
The two engaging members 80 can be steel balls, which are respectively mounted in the apertures 76.
The press member 90 also has the form of a rod. An annular recess 92 is formed on a circumference of the press member 90. In addition, a restriction slot 94 is radially formed through the press member 90. The restriction slot 94 longitudinally extends along the axis of the press member 90. The press member 90 is mounted in the cavity 75 of the adjustment rod 70 and slidable along the cavity 75. A restriction pin 95 is radially fitted in pinholes 79 of the adjustment rod and pass through the restriction slot of the press member 90. Accordingly, the press member is movable by a distance limited within a range without being extracted out of the cavity 75 of the adjustment rod 70. A second resilient member 96 is mounted in the cavity 75 of the adjustment rod 70 in abutment with the press member 90. The second resilient member 96 exerts a resilient force on the press member 90 to normally keep the press member 90 in an upper dead end where there is a drop between the annular recess 92 of the press member and the engaging members 80. Referring to
Referring to
Please refer to
When installing the tooling disk, on the basis of the direction of
As aforesaid, the annular groove 12 has a beveled top wall 121 and a beveled bottom wall 122, and the abutment end 52 has a beveled top edge 521 and a beveled bottom edge 522. The beveled top wall 121 and beveled bottom wall 122 serve to guide the beveled top edge 521 and beveled bottom edge 522, whereby the abutment end 52 can be moved into the annular groove 12 and engaged therein as tightly as possible. On the other hand, the securing assembly 20 can be automatically adjusted to an optimal height/position for clamping the tooling disk.
Due to different tooling disks have different thickness, an operator can adjust the protruding length of the adjustment rod 70 so as to change the gap between the annular groove 12 and the gasket 120 in accordance with the thickness of the tooling disk. Accordingly, the present invention is applicable to various tooling disks with different thickness. The adjustment process is as shown in
Please refer to
When detaching the tooling disk, an operator only needs to shift the securing assembly 20 to the unlocking state as shown in
According to the above arrangement, an operator can replace the tooling disk without using any tool. The operator only needs to shift the securing assembly between the locking state and the unlocking state to replace the tooling disk.
In contrast, the conventional engaging means is installed in the body of a grinding tool for engaging with the rotary shaft, permitting an operator to install/uninstall a tooling disk with a hand tool; the present invention provides a replacement measure, which is totally different from the traditional replacement measure. The present invention is free from any engaging means for fixing the rotary shaft. By means of the present invention, an operator can replace the tooling disk without using any hand tool.
Through a real test performed by this applicant, it is proved that the tooling disk can be effectively secured to the rotary shaft and rotated therewith. The replacement of the tooling disk can be conveniently and quickly completed in seconds.
The present invention has a simple structure and is applicable to the grinding tool as an external device without changing the internal structure of the grinding tool. In addition, the present invention is easy to manufacture at lower cost.
The above embodiment is only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiment can be made without departing from the spirit of the present invention. For example, the securing plate can be a one-piece component instead of the front and rear pieces of the above embodiment, and the one-piece securing plate can be latched with or unlatched from the securing seat.