A clutch fastening type coupling device for testing a chainsaw engine

Abstract

The utility model discloses a kind of oil saw engine test clutch fastening type coupling device, including the clutch driving disc of being sleeved on the output shaft of oil saw engine and the fastening type coupling of being sleeved on output shaft;The fastening type coupling includes the connecting disc of being sleeved on output shaft and the taper fastener of being inserted between connecting disc and output shaft, the taper fastener and connecting disc are connected by fastening bolt, the clutch driving disc is contained in the end face of connecting disc close to oil saw engine.This utility model is reasonable in design, convenient to operate, the transmission of output shaft of oil saw engine is realized as optical axis under power by connecting disc and taper fastener, it is convenient for oil saw engine test, and improves test stability.

Description

Technical Field

[0001] This utility model belongs to the field of gasoline chainsaw engine testing technology, and in particular relates to a clutch-fastening coupling device for testing chainsaw engines. Background Technology

[0002] A chainsaw engine powers a gasoline chainsaw. To determine the power performance of a gasoline chainsaw, an engine test bench is needed to test the chainsaw engine. During the chainsaw engine bench test, a coupling is required to connect the chainsaw engine output shaft to the dynamometer spindle. Chainsaw engines are generally single-cylinder gasoline engines, characterized by high speed and high vibration during operation.

[0003] Traditional chainsaw engine couplings typically use a threaded structure, where the coupling is screwed onto the external thread of the chainsaw engine's output shaft. This type of coupling carries the risk of the threads loosening during testing, causing the coupling to detach and potentially damaging the engine and equipment. Furthermore, it is unsuitable for chainsaw engine output shafts that are smooth shafts.

[0004] Therefore, there is currently a lack of a reasonably designed clutch-fastening coupling device for chainsaw engine testing, which can achieve power transmission from the output shaft of the chainsaw engine to a bare shaft through a connecting disc and a tapered fastener, thus facilitating chainsaw engine testing. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a clutch-type coupling device for testing chainsaw engines, which is reasonable in design and convenient in operation. Through the connecting plate and the tapered fastener, the power transmission of the output shaft of the chainsaw engine is realized under the condition of an optical shaft, which is convenient for testing chainsaw engines.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a clutch fastening coupling device for testing a chainsaw engine, including a clutch drive disc sleeved on the output shaft of the chainsaw engine and a fastening coupling sleeved on the output shaft; The fastening coupling includes a connecting disc sleeved on the output shaft and a tapered fastener inserted between the connecting disc and the output shaft. The tapered fastener and the connecting disc are connected by fastening bolts. The clutch drive disc is housed in the end face of the connecting disc near the chainsaw engine.

[0007] In the aforementioned clutch fastening coupling device for testing a chainsaw engine, the clutch drive disc is threadedly mounted on the output shaft, and the end face of the clutch drive disc is close to the inner surface of the connecting disc and the end face of the tapered fastener.

[0008] The aforementioned clutch-fastening coupling device for testing a chainsaw engine further includes a connecting disc comprising an integrally formed first ring disc body, an intermediate connecting body, and a second ring disc body, wherein the first ring disc body and the intermediate connecting body are provided with mounting holes for inserting a tapered fastener. The second ring disc has a countersunk hole on the end face near the chainsaw engine, and the clutch drive disc is accommodated in the countersunk hole.

[0009] The aforementioned clutch fastening coupling device for testing a chainsaw engine is further provided in that the tapered fastener includes an annular body and a frustum integrally formed with the annular body. A central cylindrical hole is provided through the interior of the annular body and the frustum. A longitudinal slit communicating with the central cylindrical hole is provided on the annular body and the frustum. The longitudinal slit is arranged along the length direction of the annular body and the frustum. The tapered fastener is fitted onto the output shaft through a central cylindrical hole.

[0010] The aforementioned clutch-fastening coupling device for testing a chainsaw engine further includes a mounting hole comprising a cylindrical mounting hole and a frustum-shaped mounting hole communicating with the cylindrical mounting hole. The cylindrical mounting hole penetrates the first annular disc and extends into the intermediate connecting body, while the frustum-shaped mounting hole is located within the remaining intermediate connecting body. The frustum-shaped body is inserted into the frustum-shaped mounting hole and sleeved on the output shaft, while the annular body is located within the cylindrical mounting hole.

[0011] The aforementioned clutch-fastening coupling device for testing a chainsaw engine is further provided with a plurality of evenly distributed first threaded holes in the intermediate connecting body, the first threaded holes being arranged around the circumference of the mounting hole. The outer diameter of the annular body is larger than the large diameter of the frustum body. The annular body extending out of the frustum body has a plurality of evenly distributed second threaded holes and through holes, which are arranged alternately. The fastening bolt passes through the through hole and the first threaded hole to connect the annulus and the connecting disc into one unit.

[0012] In the aforementioned clutch-fastening coupling device for testing a chainsaw engine, two symmetrically arranged pin holes are provided on the portion of the first ring disc extending from the cylindrical mounting hole, and pins are installed in the pin holes.

[0013] In the aforementioned clutch-fastening coupling device for testing a chainsaw engine, a clearance hole is further provided in the end face of the second ring disc near the chainsaw engine. The clearance hole is located between the countersunk hole and the conical mounting hole, and the clearance hole, the countersunk hole, and the conical mounting hole are all connected and their center lines coincide.

[0014] This utility model has the following advantages compared with the prior art: 1. This utility model has a simple structure, reasonable design, and is easy to install and deploy, with stable and reliable connection.

[0015] 2. The tapered fastener in this utility model is designed to secure the connecting disc to the output shaft. Compared with conventional flat key or spline connections, it provides a better fastening and is easier to install, solving the problems of loose connections or inconvenient installation in traditional connection methods.

[0016] 3. The fastening coupling of this utility model can not only realize the transmission of power from the output shaft, but also prevent the clutch from loosening and falling off the output shaft. It is suitable for the case where the output shaft connection part is a bare shaft, which is different from the current threaded connection method of couplings.

[0017] 4. The connecting plate in this utility model serves two purposes: to house the clutch drive plate within the end face of the connecting plate near the chainsaw engine, and to secure the tapered fastener. The overall structure is compact, enabling both direct power transmission from the chainsaw engine via the output shaft and power transmission via the clutch.

[0018] 5. The tapered fastener and the connecting plate of this utility model are connected by fastening bolts. The axial clamping force of the fastening bolts is changed into a force that grips the output shaft and the connecting plate through the tapered structure, and they are fastened as one, thereby improving the fastening effect.

[0019] 6. The most significant feature of this utility model is that the speed is lower than the clutch engagement speed. The power is transmitted between the output shaft of the dynamometer and the chainsaw engine by a fastening coupling of the optical shaft. Once the speed is higher than the clutch engagement speed, the centrifugal block on the clutch drive disc on the output shaft moves radially outward under the action of centrifugal force and contacts the inner wall of the countersunk hole of the second ring disc in the connecting disc. At this time, the clutch also participates in transmitting power.

[0020] In summary, this utility model is reasonably designed and easy to operate. Through the connecting plate and tapered fastener, it enables the transmission of power from the output shaft of the chainsaw engine to the optical shaft, which facilitates chainsaw engine testing and improves test stability.

[0021] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this utility model.

[0023] Figure 2 This is a schematic diagram of the connecting disc of this utility model.

[0024] Figure 3 This is a schematic diagram of the internal structure of the connecting disc of this utility model.

[0025] Figure 4 for Figure 3 The right view.

[0026] Figure 5 This is a schematic diagram of the tapered fastener of this utility model.

[0027] Figure 6 for Figure 5 The right view.

[0028] Explanation of reference numerals in the attached figures: 1—Chainsaw engine; 2—Output shaft; 3—Clutch drive plate; 4—Connecting disc; 4-1—Counterhead hole; 4-3—Conical mounting hole; 4-4—First threaded hole; 4-5—Pin; 4-6—Cylindrical mounting hole; 4-7—First annular disc; 4-8—Intermediate connecting body; 4-9—Second ring disc; 4-10—Displacement hole; 4-11—Pin hole; 5—Tapered fastener; 5-1—Longitudinal slot; 5-2—Second threaded hole; 5-3—Through hole; 5-4—Central cylindrical hole; 5-5—Frustum-shaped body; 5-6—Ring; 6—Fasting bolt. Detailed Implementation

[0029] like Figures 1 to 6 The clutch fastening coupling device for testing a chainsaw engine shown includes a clutch drive disc 3 sleeved on the output shaft 2 of the chainsaw engine 1 and a fastening coupling sleeved on the output shaft 2. The fastening coupling includes a connecting disc 4 sleeved on the output shaft 2 and a tapered fastener 5 inserted between the connecting disc 4 and the output shaft 2. The tapered fastener 5 and the connecting disc 4 are connected by fastening bolts 6. The clutch drive disc 3 is housed in the end face of the connecting disc 4 near the chainsaw engine 1.

[0030] In this embodiment, the clutch drive plate 3 is threaded onto the output shaft 2, and the end face of the clutch drive plate 3 is close to the inner surface of the connecting plate 4 and the end face of the tapered fastener 5.

[0031] In this embodiment, the connecting disc 4 includes an integrally formed first ring disc body 4-7, an intermediate connecting body 4-8, and a second ring disc body 4-9. The first ring disc body 4-7 and the intermediate connecting body 4-8 are provided with mounting holes for inserting the tapered fastener 5. The second ring disc 4-9 has a countersunk hole 4-1 on the end face near the chainsaw engine 1, and the clutch drive disc 3 is accommodated in the countersunk hole 4-1.

[0032] In this embodiment, the tapered fastener 5 includes an annular body 5-6 and a frustum 5-5 integrally formed with the annular body 5-6. A central cylindrical hole 5-4 is provided through the interior of the annular body 5-6 and the frustum 5-5. A longitudinal slit 5-1 communicating with the central cylindrical hole 5-4 is provided on the annular body 5-6 and the frustum 5-5. The longitudinal slit 5-1 is arranged along the length direction of the annular body 5-6 and the frustum 5-5. The tapered fastener 5 is fitted onto the output shaft 2 through the central cylindrical hole 5-4.

[0033] In this embodiment, the mounting hole includes a cylindrical mounting hole 4-6 and a frustum mounting hole 4-3 communicating with the cylindrical mounting hole 4-6. The cylindrical mounting hole 4-6 penetrates the first annular disc 4-7 and extends into the intermediate connecting body 4-8. The frustum mounting hole 4-3 is located within the remaining intermediate connecting body 4-8. The frustum 5-5 is inserted into the frustum mounting hole 4-3 and sleeved on the output shaft 2. The annular disc 5-6 is located within the cylindrical mounting hole 4-6.

[0034] In this embodiment, the intermediate connecting body 4-8 is provided with a plurality of evenly distributed first threaded holes 4-4, which are arranged around the circumference of the mounting hole. The outer diameter of the annular body 5-6 is larger than the large diameter of the frustum body 5-5. The annular body 5-6 extending out of the frustum body 5-5 has a plurality of evenly distributed second threaded holes 5-2 and through holes 5-3, which are arranged alternately. The fastening bolt 6 passes through the through hole 5-3 and the first threaded hole 4-4 to connect the annulus 5-6 and the connecting disc 4 into one unit.

[0035] In this embodiment, the portion of the first annular disc 4-7 extending out of the cylindrical mounting hole 4-6 is provided with two symmetrically arranged pin holes 4-11, and a pin 4-5 is installed in the pin holes 4-11.

[0036] In this embodiment, a clearance hole 4-10 is also provided in the end face of the second ring disc 4-9 near the chainsaw engine 1. The clearance hole 4-10 is located between the countersunk hole 4-1 and the conical mounting hole 4-3. The clearance hole 4-10, the countersunk hole 4-1, and the conical mounting hole 4-3 are all connected and their center lines coincide.

[0037] In this embodiment, during actual use, there is a through hole 5-3 between two adjacent second threaded holes 5-2, and the number of second threaded holes 5-2, through holes 5-3, and first threaded holes 4-4 are all 3. In actual use, this number can be adjusted and is not specifically limited.

[0038] In this embodiment, the clutch drive plate 3 is a centrifugal clutch that comes with the gasoline chainsaw engine, which is a device already in use in the field.

[0039] In this embodiment, the tapered fastener 5 is provided to fasten the connecting disc 4 to the output shaft 2. Compared with conventional flat key or spline connections, it provides better fastening and is easier to install, solving the problem of loose connections or inconvenient installation in traditional connection methods.

[0040] In addition, its fastening coupling can not only transmit power to the output shaft, but also prevent the clutch from loosening and falling off the output shaft 2. It is suitable for the case where the connection part of the output shaft 2 is a bare shaft, which is different from the current threaded connection method of couplings.

[0041] In this embodiment, a longitudinal slit 5-1 is provided and arranged along the length of the annular body 5-6 and the frustum 5-5. This serves two purposes: firstly, it allows the tapered fastener 5 to pass through the connecting disc 4 and be fitted onto the output shaft 2 via the central cylindrical hole 5-4; secondly, it allows the fastening bolt 6 to be tightened through the through hole 5-3 and the first threaded hole 4-4 when fitted onto the output shaft 2, thereby reducing the gap in the longitudinal slit 5-1 and ensuring that the inner wall of the frustum 5-5 is in close contact with the output shaft 2, thus securing the connection. Furthermore, this structure also reduces the difficulty of machining. Under conditions where machining requirements are not high, it ensures normal operation under high-speed conditions. In this embodiment, it should be noted that the frustum 5-5 is slightly larger than the frustum mounting hole 4-3, and the diameter of the central cylindrical hole 5-4 is the same as that of the output shaft 2, in order to ensure the fastening effect.

[0042] Furthermore, in actual use, the taper of the frustum 5-5 and the frustum mounting hole 4-3 are the same. On the same cross section, the outer surface diameter of the frustum 5-5 is 0.5mm larger than the hole diameter of the frustum mounting hole 4-3. This dimension is not specifically limited, as long as it meets the usage requirements.

[0043] In this embodiment, it should be noted that when the frustum 5-5 is inserted into the frustum mounting hole 4-3 under the fastening bolt 6, the axial force of the fastening bolt 6 is converted into a radial clamping force by using the conical surface fit; at the same time, the longitudinal slot 5-1 provides structural space for it to generate the necessary elastic deformation under the action of the radial clamping force, so that the frustum 5-5 contracts to hug the ratio output shaft 2.

[0044] In this embodiment, the connecting plate 4 is provided both to accommodate the clutch drive plate 3 within the end face of the connecting plate 4 near the chainsaw engine 1 and to secure the tapered fastener 5. The overall structure is compact and can both transmit power from the chainsaw engine 1 and allow the clutch to participate in the power transmission.

[0045] In this embodiment, the tapered fastener 5 and the connecting disc 4 are connected by fastening bolts 6. The axial clamping force of the fastening bolts 6 is changed by the tapered structure into a force that grips the output shaft and the connecting disc, thus fastening them together as one, thereby improving the fastening effect.

[0046] In this embodiment, it should be noted that the optical shaft portion of the output shaft 2 is relatively thin, typically with a diameter of 10mm. At high speeds (greater than 6000r / min), vibrations may occur, potentially leading to shaft breakage. Therefore, a clutch drive disc 3 is provided, housed within a connecting disc 4 and a fastening coupling. Power transmission is achieved through a combination of the clutch and the fastening coupling.

[0047] In this embodiment, the through hole 5-3 and the first threaded hole 4-4 are provided so that the fastening bolt 6 can pass through the through hole 5-3 and the first threaded hole 4-4, so that the ring 5-6 and the connecting plate 4 can be connected as one unit.

[0048] In this embodiment, during actual installation, the pin 4-5 can be threaded into the pin hole 4-11 or installed with an interference fit; it is also necessary to weld the inner end of the pin 4-5 to the inner wall of the pin hole 4-11 so that the pin 4-5 and the first ring disc 4-7 are fixedly connected.

[0049] Pins 4-5 are used for connection to the dynamometer mounting plate, following a standard connection method. This connection to the dynamometer spindle mounting plate enables power transmission between the chainsaw engine output shaft and the dynamometer spindle, allowing for successful testing.

[0050] In this embodiment, it should be noted that the connection between the cylindrical pin 4-5 and the dynamometer connecting plate can refer to the connection method of the cylindrical pin and the third connecting plate in patent CN113567139B, "A Gasoline Chainsaw Engine Testing System and Its Usage Method".

[0051] In this embodiment, the first threaded hole 4-4 is located on the edge of the conical mounting hole 4-3 extending from the intermediate connector 4-8. One end of the first threaded hole 4-4 is connected to the cylindrical mounting hole 4-6, and the other end of the first threaded hole 4-4 is connected to the countersunk hole 4-1.

[0052] In this embodiment, one end of the first threaded hole 4-4 is connected to the cylindrical mounting hole 4-6, and the other end of the first threaded hole 4-4 is connected to the countersunk hole 4-1. This is to allow the first threaded hole 4-4 to be arranged in a through manner, which reduces weight on the one hand, and can be adapted to fastening bolts 6 of different lengths and specifications on the other hand, thus having good versatility.

[0053] In this embodiment, the clearance hole 4-10 is located between and connected to the countersunk hole 4-1 and the cone mounting hole 4-3. This is to allow clearance for the nut of the clutch drive plate 3 when it is fitted onto the output shaft 2, so that the nut can be embedded in the clearance hole 4-10. With the clearance hole 4-10 and the cone mounting hole 4-3 connected, the end of the tapered fastener 5 can be positioned close to the end face of the clutch drive plate 3 to prevent the clutch drive plate 3 from loosening and falling off.

[0054] In this embodiment, during actual installation, the gap between the outer edge of the clutch drive disc 3 and the inner edge of the second ring disc 4-9 is in the range of (0, 1mm), that is, greater than 0 and less than or equal to 1mm, as long as it can be installed. The clutch engagement speed is related to this gap. If the gap is small, the engagement speed is relatively low. When the clutch is engaged, the engine speed of the chainsaw engine 1 is generally in the range of 3500r / min to 5500r / min.

[0055] In this embodiment, the most significant feature of the device is that the speed is lower than the clutch engagement speed. The power is transmitted between the dynamometer and the output shaft 2 of the chainsaw engine 1 via a fastening coupling of the optical shaft. Once the speed is higher than the clutch engagement speed, the centrifugal sling on the clutch drive plate 3 moves radially outward under the action of centrifugal force and contacts the inner wall of the countersunk hole 4-1 of the second ring disc 4-9 in the connecting plate 4. At this time, the clutch also participates in transmitting power.

[0056] In practical use, the tapered fastener 5 is inserted into the connecting plate 4, and the fastening bolt 6 is passed through the through hole 5-3 and the first threaded hole 4-4 to connect the tapered fastener 5 to the connecting plate 4. The fastening bolt 6 is not tightened. The connecting plate 4 with the tapered fastener 5 is installed on the output shaft 2 of the chainsaw engine 1, and the countersunk hole 4-1 of the connecting plate 4 is installed on the outside of the clutch drive plate 3 of the chainsaw engine. After the clutch drive plate 3 is fully embedded, the fastening bolt 6 is tightened. After the tapered surface of the tapered fastener 5 is subjected to force, the longitudinal slot 5-1 of the tapered fastener 5 narrows, and the tapered fastener 5 is fastened to the output shaft 2, thereby fastening the connecting plate 4 to the output shaft 2 of the chainsaw engine 1. Install and fix pin 4-5 in pin hole 4-11, and connect it to the main shaft connecting plate of dynamometer through pin 4-5; when the chainsaw engine 1 is tested on the bench, when the speed of the chainsaw engine 1 is lower than the clutch engagement speed, the power transmission of the output shaft 2 of the chainsaw engine 1 is achieved only by the tapered fastener 5; when the speed of the chainsaw engine 1 increases to higher than the clutch engagement speed, the clutch drive plate 3 fixed on the output shaft 2 intervenes in the power transmission. Next, the clutch-locking coupling assembly is disassembled: First, loosen the fastening bolt 6 until it is removed. Then, screw the removed fastening bolt 6 into the second threaded hole 5-2 on the tapered fastener 5 and abut it against the bottom of the cylindrical mounting hole 4-6. Next, tighten the fastening bolt 6 evenly. With the head of the fastening bolt 6 limited by the connecting plate 4, the fastening bolt 6 only rotates. In this way, with the fastening bolt 6 and the tapered fastener 5 threadedly connected, the tapered fastener 5 moves along the fastening bolt 6, and the tapered fastener 5 gradually disengages from the connecting plate 4 and the output shaft 2, thereby removing the tapered fastener 5 and the connecting plate 4.

[0057] In summary, this utility model is reasonably designed and easy to operate. Through the connecting plate and tapered fastener, it enables the transmission of power from the output shaft of the chainsaw engine to the optical shaft, which facilitates chainsaw engine testing and improves test stability.

[0058] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the present utility model. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A clutch-fastening coupling device for testing a chainsaw engine, characterized in that: Includes a clutch drive disc (3) mounted on the output shaft (2) of the chainsaw engine (1) and a fastening coupling mounted on the output shaft (2); The fastening coupling includes a connecting disc (4) sleeved on the output shaft (2) and a tapered fastener (5) inserted between the connecting disc (4) and the output shaft (2). The tapered fastener (5) and the connecting disc (4) are connected by fastening bolts (6). The clutch drive disc (3) is housed in the end face of the connecting disc (4) near the chainsaw engine (1).

2. The clutch-fastening coupling device for testing a chainsaw engine according to claim 1, characterized in that: The clutch drive plate (3) is threaded onto the output shaft (2), and the end face of the clutch drive plate (3) is close to the inner surface of the connecting plate (4) and the end face of the tapered fastener (5).

3. A clutch-fastening coupling device for testing a chainsaw engine according to claim 1, characterized in that: The connecting disc (4) includes an integrally formed first ring disc body (4-7), an intermediate connecting body (4-8), and a second ring disc body (4-9). The first ring disc body (4-7) and the intermediate connecting body (4-8) are provided with mounting holes for inserting the tapered fastener (5). The second ring disc (4-9) has a countersunk hole (4-1) on the end face near the chainsaw engine (1), and the clutch drive disc (3) is accommodated in the countersunk hole (4-1).

4. A clutch-fastening coupling device for testing a chainsaw engine according to claim 3, characterized in that: The tapered fastener (5) includes an annular body (5-6) and a frustum (5-5) integrally formed with the annular body (5-6). A central cylindrical hole (5-4) is provided through the interior of the annular body (5-6) and the frustum (5-5). A longitudinal slit (5-1) communicating with the central cylindrical hole (5-4) is provided on the annular body (5-6) and the frustum (5-5). The longitudinal slit (5-1) is arranged along the length direction of the annular body (5-6) and the frustum (5-5). The tapered fastener (5) is fitted onto the output shaft (2) through the central cylindrical hole (5-4).

5. A clutch-fastening coupling device for testing a chainsaw engine according to claim 4, characterized in that: The mounting holes include a cylindrical mounting hole (4-6) and a frustum mounting hole (4-3) communicating with the cylindrical mounting hole (4-6). The cylindrical mounting hole (4-6) passes through the first annular disc (4-7) and extends into the intermediate connecting body (4-8). The frustum mounting hole (4-3) is located within the remaining intermediate connecting body (4-8). The frustum body (5-5) is inserted into the frustum mounting hole (4-3) and sleeved on the output shaft (2). The annular body (5-6) is located within the cylindrical mounting hole (4-6).

6. A clutch-fastening coupling device for testing a chainsaw engine according to claim 4, characterized in that: The intermediate connector (4-8) is provided with a plurality of evenly distributed first threaded holes (4-4), which are arranged around the circumference of the mounting hole. The outer diameter of the annular body (5-6) is larger than the large diameter of the frustum body (5-5). The annular body (5-6) extending out of the frustum body (5-5) has a plurality of evenly distributed second threaded holes (5-2) and through holes (5-3), which are arranged alternately. The fastening bolt (6) passes through the through hole (5-3) and the first threaded hole (4-4) to connect the annulus (5-6) and the connecting disc (4) into one unit.

7. A clutch-fastening coupling device for testing a chainsaw engine according to claim 5, characterized in that: The first ring disc (4-7) has two symmetrically arranged pin holes (4-11) on the part extending out of the cylindrical mounting hole (4-6), and a pin (4-5) is installed in the pin hole (4-11).

8. A clutch-fastening coupling device for testing a chainsaw engine according to claim 5, characterized in that: The second ring disc (4-9) is also provided with a clearance hole (4-10) on the end face near the chainsaw engine (1). The clearance hole (4-10) is located between the countersunk hole (4-1) and the cone mounting hole (4-3). The clearance hole (4-10) and the countersunk hole (4-1) are all connected to the cone mounting hole (4-3) and their center lines coincide.

Images