Contact force indicator device with a tool holder

Abstract

In a contact force indicator device (150) for indicating a contact force (299) acting on a tool insert, comprising a tool holder (157) for at least partially receiving a tool insert, a contact force measuring unit (158) for measuring a contact force acting on the tool holder (157), and a contact force display unit (159) for displaying the measured contact force, the contact force measuring unit (158) has a first sleeve (151) and a second sleeve (152) which is arranged coaxially and axially displaceable (203) on the first sleeve, wherein the first sleeve is connected to the second sleeve via a limiting element axially displaceable on the first sleeve in order to define a maximum position (298) of the second sleeve when the second sleeve is axially displaced away from the first sleeve, wherein the first sleeve and the second sleeve form a common receptacle for receiving a spring element (156),that the second sleeve is acted upon in the direction of the maximum position (298), and wherein the maximum position (298) is associated with a minimum contact force.

Description

State of the art

[0001] The present invention relates to a contact force display device for displaying a contact force acting on an insert tool.

[0002] From the prior art, display devices in the form of drilling depth display devices are known which display the current drilling depth of a drilling tool during a drilling process to a user of a hand-held power tool. Disclosure of the invention

[0003] The invention relates to a contact force display device for displaying a contact force acting on an insert tool, comprising a tool holder for at least partially receiving an insert tool, a contact force measuring unit for measuring a contact force acting on the tool holder, and a contact force display unit for displaying the measured contact force.The contact pressure measuring unit has a first sleeve and a second sleeve which is arranged coaxially and displaceably in the axial direction on the first sleeve, wherein the first sleeve is connected to the second sleeve via a limiting element which is axially displaceable on the first sleeve in order to define a maximum position of the second sleeve in the event of an axial displacement of the second sleeve directed away from the first sleeve, wherein the first sleeve and the second sleeve form a common receptacle for receiving a spring element which acts on the second sleeve in the direction of the maximum position, and wherein the maximum position is associated with a minimum contact pressure.

[0004] The invention thus enables the provision of a contact force display device that can safely and reliably measure a contact force acting on an insert tool and display it to a user in real time, so that the insert tool can be protected and a longer service life can thus be enabled.

[0005] Preferably, the first sleeve has an interface for arranging on a machine tool holder of a hand-held power tool.

[0006] This means that the contact force indicator can be easily and simply mounted on a handheld power tool.

[0007] Preferably, the second sleeve forms the tool holder.

[0008] This makes it easy to create a suitable tool holder.

[0009] According to one embodiment, the tool holder forms a polygonal internal receptacle, in particular a HEX receptacle, for at least partially receiving an insert tool.

[0010] This means that an insert tool with a HEX holder can be held in the tool holder in a stable and reliable manner.

[0011] Preferably, the first sleeve has a first annular receptacle and the second sleeve has a second annular receptacle, wherein the first and second annular receptacles together form the receptacle for receiving the spring element.

[0012] This allows for a secure and robust mounting of the spring element.

[0013] The limiting element preferably comprises a screw with a screw head.

[0014] Thus, a suitable limiting element can be provided in a simple manner.

[0015] According to one embodiment, the first sleeve has a bottom surface facing the second sleeve with a recess for the screw, and the second sleeve has a screw thread for forming a screw connection with the screw, wherein the screw head rests against the bottom surface in the maximum position of the second sleeve and is spaced from the bottom surface along a longitudinal extent of the screw depending on a respective contact pressure force.

[0016] This enables a safe and reliable movement of the two sleeves along their longitudinal extent.

[0017] Preferably, the second sleeve has an inner receptacle formed as a polygon, and the first sleeve has an outer circumference associated with the inner receptacle.

[0018] This enables safe and reliable torque transmission from a hand-held power tool to a contact force display device connected to it.

[0019] The second sleeve preferably has an internal receptacle for receiving the first sleeve, wherein the first sleeve can be immersed into the second sleeve depending on a respective contact pressure force, and wherein the contact pressure display unit is arranged on an outer circumference of the first sleeve.

[0020] This makes it easy to arrange the two sleeves appropriately relative to each other.

[0021] Preferably, the contact pressure display unit is designed as a scale arranged on the outer circumference and / or has at least two color-coded display areas.

[0022] This means that the measured contact force can be safely and reliably visualized to the user. Short description of the drawings

[0023] The invention is explained in more detail in the following description using exemplary embodiments illustrated in the drawings. They show: Fig. 1 a contact force indicator device according to the invention, which is arranged between a hand-held power tool and an insert tool, Fig. 2 a longitudinal section through the contact force display device of Fig. 1, Fig. 3 a perspective sectional view through the contact force display device of Fig. 1 and Fig. 2, and Fig. 4 a perspective view of the contact force display device of Fig. 1 to Fig. 3. Description of the embodiments

[0024] In the figures, elements with the same or comparable function are provided with identical reference symbols and are described in detail only once.

[0025] Fig. 1 shows an exemplary handheld power tool 100, illustratively comprising a housing 110 with a handle 105. The handheld power tool 100 is associated with a machine tool holder 130 for receiving an insert tool 140, e.g., a drill. Illustratively, the insert tool 140 is designed as a diamond core bit.

[0026] An electric drive motor 120 for driving the machine tool holder 130 is preferably arranged in the housing 110. The drive motor 120 can preferably be switched on and off via a manual switch 117. The manual switch 117 is preferably arranged on the handle 105.

[0027] Illustratively, an optional auxiliary handle 118 is assigned to the handheld power tool 100. The auxiliary handle 118 is arranged, for example, in the area of ​​the machine tool holder 130.

[0028] The handheld power tool 100 preferably has a power cable 119 for mains-dependent power supply. Alternatively, the handheld power tool 100 can have a battery pack for mains-independent power supply. Illustratively, the handheld power tool 100 is designed as a drill, but can alternatively also be designed, for example, as a screwdriver.

[0029] On the machine tool holder 130, a contact pressure display device 150 is illustratively arranged for displaying a contact pressure acting on an insert tool 140 (299 in Fig. 2). For at least partially receiving the insert tool 140, the contact force indicator device 150 has a tool holder 157. Preferably, a receiving shaft 142 of the insert tool 140 is arranged in the tool holder 157.

[0030] The insert tool 140 can be, for example, a drilling tool. Illustratively, the insert tool 140 is designed as a diamond core bit.

[0031] The tool holder 157 and the machine tool holder 130 are preferably coupled to one another in such a way that, during operation of the handheld power tool 100, a torque is transmitted from the machine tool holder 130 to the tool holder 157 and thus from there to the insert tool 140. In this case, the coupling between the tool holder 157 and the machine tool holder 130 can be detachable. In this case, the contact force indicator device 150 is designed as an additional part or adapter, in particular one that can be retrofitted.

[0032] Preferably, the contact force display device 150 has a contact force measuring unit 158 ​​for measuring a contact force acting on the tool holder 157 (299 in Fig. 2), as well as a contact force display unit 159 for displaying the measured contact force (299 in Fig. 2). The contact force measuring unit 158 ​​preferably has a first sleeve 151 and a second sleeve 152. The first sleeve 151 is connected to the second sleeve 152 via a limiting element 160 that is axially displaceable on the first sleeve 151 in order to define a maximum position (298 in Fig. 2) of the second sleeve 152 during an axial displacement of the second sleeve 152 directed away from the first sleeve 151.

[0033] Preferably, the first sleeve 151 has an interface 153 for arranging on the machine tool holder 130 of the hand-held power tool 100. Furthermore, the second sleeve 152 preferably forms the tool holder 157. The second sleeve 152 is preferably coaxial and in the axial direction (203 in Fig. 2) is slidably arranged on the first sleeve 151. The first sleeve 151 and the second sleeve 152 preferably form a common receptacle (219 in Fig. 2) for receiving a spring element 156. Furthermore, the second sleeve 152 preferably has an internal receptacle 154, which is formed as a polygon.

[0034] Fig. 2 shows the contact force display device 150 of Fig. 1 and illustrates the structure and arrangement of the first and second sleeves 151, 152. At a first, illustratively left axial end 201 of the contact pressure display device 150, the first sleeve 151 is provided with the interface 153 for arranging on the machine tool holder 130 of the hand-held power tool 100 of Fig. 1. At an opposite second, illustratively right axial end 202 of the contact force indicator device 150, the tool holder 157 for receiving the insert tool 140 of Fig. 1. Furthermore, the contact force indicator 150 illustratively has a longitudinal axis 204. An axial direction 203 of the contact force indicator 150 illustratively extends along the longitudinal axis 204.

[0035] The second sleeve 152 is preferably arranged coaxially on the first sleeve 151 and displaceable in the axial direction 203. The first sleeve 151 and the second sleeve 152 form a common receptacle 219 for receiving the spring element 156. The first sleeve 151 preferably has a first annular receptacle 211 and the second sleeve 152 has a second annular receptacle 239. The first and second annular receptacles 211, 239 together form the receptacle 219 for receiving the spring element 156. The spring element 156 is preferably arranged in the axial direction 203 between a bottom surface 212 of the first sleeve 151 assigned to the receptacle 211 and a bottom surface 238 of the second sleeve 152 assigned to the receptacle 239.

[0036] The second sleeve 152 has, for example, an annular web 230 to form the second annular receptacle 239. The receptacle 239 is illustratively formed between the annular web 230 and an outer circumference of the second sleeve 152. Furthermore, an inner receptacle 154 is arranged, for example, perpendicular to the longitudinal axis 204 within the annular web 230. The inner receptacle 154 is preferably formed as a polygon. Furthermore, the first sleeve 151 has an outer circumference 213 associated with the inner receptacle 154.

[0037] The spring element 156 is preferably arranged on an outer circumference 232 of the annular web 230. The spring element 156 is preferably designed to bias the second sleeve 152 toward a maximum position 298. The maximum position 298 is preferably associated with a minimum contact force. An exemplary minimum contact force applied to the second end 202 of the contact force indicator 150 is illustrated by an arrow 299.

[0038] The second sleeve 152 preferably has an internal receptacle 239 for receiving the first sleeve 151, wherein the first sleeve can be inserted into the second sleeve 152 depending on the contact pressure present at the time. An outer circumference 214 of the first sleeve 151 can be arranged in the internal receptacle 239. It should be noted that, alternatively, the first sleeve 151 can also receive the second sleeve 152. In this case, the first sleeve 151 is assigned an internal receptacle in which the second sleeve 152 can be arranged.

[0039] According to one embodiment, the limiting element 160 comprises a screw 260 with a screw head 262. A longitudinal extension 265 of the screw 260 is preferably aligned in the axial direction 203.

[0040] The first sleeve 151 has a bottom surface 215 facing the second sleeve 152, said bottom surface having a recess 216 for the screw 260. Furthermore, the second sleeve 152 has a screw thread 234 for forming a screw connection with the screw 260. In the maximum position of the second sleeve 152, the screw head 262 rests against the bottom surface 215, and depending on a respective existing contact force 299 along the longitudinal extent 265 of the screw 260, the screw head 262 is spaced from the bottom surface 215. It is noted that a plurality of screws 260 can also be used. Furthermore, it is noted that screws 260 can alternatively or optionally be arranged in the receptacle 219. Furthermore, the spring element 156 can alternatively or optionally be arranged centrally, i.e., in the internal receptacle 154.

[0041] Preferably, the tool holder 157 forms a polygonal internal receptacle 297, in particular a HEX receptacle, for at least partially receiving the insert tool 140 of Fig. 1. Furthermore, the contact force display unit 159 is arranged on the outer circumference 214 of the first sleeve 151. Furthermore, Fig. 2 an axial position 291 along the longitudinal axis 204 and an arrow 292 illustrating a viewing direction.

[0042] Fig. 3 shows the contact force display device 150 of Fig. 1 and Fig. 2 with the first sleeve 151 and the second sleeve 152, wherein the contact force indicator 150 is illustratively arranged at the axial position 291 of Fig. 2 and in the direction of arrow 292 of Fig. 2 is considered. Fig. Figure 3 illustrates the arrangement of the first and second sleeves 151, 152 coaxially to each other or within each other. Here, the spring element 156 is Fig. 2 in the receptacle 219 or in the radial direction between the first and second sleeves 151, 152. In addition, Fig. 3 the second sleeve 152 with its inner receptacle 154 formed as a polygon, as well as the associated outer circumference 213 of the first sleeve 151.

[0043] Fig. 4 shows the contact force display device 150 of Fig. 1 to Fig. 3 with the first and second sleeve 151, 152. Fig. 4 the contact force display unit 159.

[0044] According to one embodiment, the contact force display unit 159 is designed as a scale 415 arranged on the outer circumference 214 of the first sleeve 151. Alternatively or optionally, the contact force display unit 159 has at least two color-coded display areas 411, 412. In this case, the display area 411 can visualize an optimal contact force, and the display area 412 visualizes an excessive contact force, at which the insert tool 140 of Fig. 1 is subjected to too much stress.

[0045] For example, display area 411 may be marked green and display area 412 may be marked red. Please note that display areas 411 and 412 may also have any other color.

Claims

[1] Contact force display device (150) for displaying a contact force (299) acting on an insert tool (140), comprising a tool holder (157) for at least partially receiving an insert tool (140), a contact force measuring unit (158) for measuring a contact force (299) acting on the tool holder (157), and a contact force display unit (159) for displaying the measured contact force (299), wherein the contact force measuring unit (158) comprises a first sleeve (151) and a second sleeve (152) arranged coaxially and displaceably in the axial direction (203) on the first sleeve (151), wherein the first sleeve (151) is connected to the second sleeve (152) via a limiting element (160) axially displaceable on the first sleeve (151) in order to define a maximum position (298) of the second sleeve (152) in the event of an axial displacement of the second sleeve (152) directed away from the first sleeve (151),wherein the first sleeve (151) and the second sleeve (152) form a common receptacle (219) for receiving a spring element (156) which acts on the second sleeve (152) in the direction of the maximum position (298), and wherein the maximum position (298) is associated with a minimum contact force (299). [2] Contact force display device according to claim 1, characterized by that the first sleeve (151) has an interface (153) for arranging on a machine tool holder (130) of a hand-held power tool (100). [3] Contact force display device according to claim 1 or 2, characterized by that the second sleeve (152) forms the tool holder (157). [4] Contact force display device according to claim 3, characterized by that the tool holder (157) forms a polygonal internal holder (297), in particular a HEX holder, for at least partially receiving an insert tool (140). [5] Contact force display device according to one of the preceding claims, characterized by that the first sleeve (151) has a first annular receptacle (211) and the second sleeve (152) has a second annular receptacle (239), and the first and second annular receptacles (211, 239) together form the receptacle (219) for receiving the spring element (156). [6] Contact force display device according to one of the preceding claims, characterized by that the limiting element (160) has a screw (260) with a screw head (262). [7] Contact force display device according to claim 6, characterized byin that the first sleeve (151) has a bottom surface (215) facing the second sleeve (152) with a recess (216) for the screw (260), and the second sleeve (152) has a screw thread (234) for forming a screw connection with the screw (260), wherein the screw head (262) rests against the bottom surface (215) in the maximum position of the second sleeve (152) and is spaced from the bottom surface (215) along a longitudinal extent (265) of the screw (260) depending on a respectively existing contact pressure force (299). [8] Contact force display device according to one of the preceding claims, characterized by that the second sleeve (152) has an inner receptacle (154) which is designed as a polygon, and the first sleeve (151) has an outer circumference (213) associated with the inner receptacle (154). [9] Contact force display device according to one of the preceding claims, characterized byin that the second sleeve (152) has an internal receptacle (239) for receiving the first sleeve (151), wherein the first sleeve can be immersed into the second sleeve (152) depending on a respective contact pressure force present, and wherein the contact pressure display unit (159) is arranged on an outer circumference (214) of the first sleeve (151). [10] Contact force indicator device according to claim 9, characterized by that the contact pressure display unit (159) is designed as a scale (415) arranged on the outer circumference (214) and / or has at least two color-coded display areas (411, 412).

Images